1
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Eraslan K, Altınbay A, Nofar M. In-situ self-reinforcement of amorphous polylactide (PLA) through induced crystallites network and its highly ductile and toughened PLA/poly(butylene adipate-co-terephthalate) (PBAT) blends. Int J Biol Macromol 2024; 272:132936. [PMID: 38848828 DOI: 10.1016/j.ijbiomac.2024.132936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 05/26/2024] [Accepted: 06/04/2024] [Indexed: 06/09/2024]
Abstract
Crystallites of a semicrystalline polylactide (cPLA) were induced in an amorphous PLA (aPLA) and its blends with poly(butylene adipate-co-terephthalate) (PBAT) to achieve in-situ self-reinforced PLA based structures. The approach involved the melt blending of cPLA as a minor phase with aPLA and its blends with PBAT at processing temperatures below the crystal melting peak of cPLA. An injection molding (IM) process was first adopted to obtain self-reinforced PLA (SR-PLA) structures at aPLA/cPLA weight ratios of 100/0, 95/5, 90/10, 85/15, and 80/20. IM barrel and mold temperatures revealed crucial impacts on preserving the cPLA crystallites and thereby enhancing the final mechanical performance of SR-PLA (i.e., aPLA/cPLA) samples. SR-PLA samples at various aPLA/cPLA weight ratios of 100/0, 90/10, 80/20, and 70/30 were then melt blended with PBAT to produce SR-PLA/PBAT at a given ratio of 85/15. These blends were first prepared in an internal melt mixer (MM) to evaluate the rheological properties. The rheological analysis confirmed the significance of cPLA reinforcing efficiency within SR-PLA and its corresponding blends with PBAT. Similar SR-PLA/PBAT blends were also prepared using the IM process to explore their thermal and mechanical characteristics. The effect of cPLA concentrations in blends was distinctive, leading to significant enhancements in stain at break and toughness values. This was due to the increased crystallite network within the matrix, further refining PBAT droplets. Morphological analysis of the melt-processed blends through MM and IM also revealed that the PBAT droplets were further refined when the IM process was applied. The induced shear during the molding could have further elongated the cPLA crystallites towards a fiberlike structure, which could additionally cause the matrix viscosity to increase and refine the PBAT droplets.
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Affiliation(s)
- Kerim Eraslan
- Sustainable & Green Plastics Laboratory, Metallurgical & Materials Engineering Department, Faculty of Chemical and Metallurgical Engineering, Istanbul Technical University, Istanbul 34469, Turkey
| | - Aylin Altınbay
- Sustainable & Green Plastics Laboratory, Metallurgical & Materials Engineering Department, Faculty of Chemical and Metallurgical Engineering, Istanbul Technical University, Istanbul 34469, Turkey; Metallurgical & Materials Engineering Department, Faculty of Chemical and Metallurgical Engineering, Yildiz Technical University, Esenler, Istanbul 34220, Turkey
| | - Mohammadreza Nofar
- Sustainable & Green Plastics Laboratory, Metallurgical & Materials Engineering Department, Faculty of Chemical and Metallurgical Engineering, Istanbul Technical University, Istanbul 34469, Turkey.
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2
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Gonçalves LFFF, Reis RL, Fernandes EM. Forefront Research of Foaming Strategies on Biodegradable Polymers and Their Composites by Thermal or Melt-Based Processing Technologies: Advances and Perspectives. Polymers (Basel) 2024; 16:1286. [PMID: 38732755 PMCID: PMC11085284 DOI: 10.3390/polym16091286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 04/13/2024] [Accepted: 04/26/2024] [Indexed: 05/13/2024] Open
Abstract
The last few decades have witnessed significant advances in the development of polymeric-based foam materials. These materials find several practical applications in our daily lives due to their characteristic properties such as low density, thermal insulation, and porosity, which are important in packaging, in building construction, and in biomedical applications, respectively. The first foams with practical applications used polymeric materials of petrochemical origin. However, due to growing environmental concerns, considerable efforts have been made to replace some of these materials with biodegradable polymers. Foam processing has evolved greatly in recent years due to improvements in existing techniques, such as the use of supercritical fluids in extrusion foaming and foam injection moulding, as well as the advent or adaptation of existing techniques to produce foams, as in the case of the combination between additive manufacturing and foam technology. The use of supercritical CO2 is especially advantageous in the production of porous structures for biomedical applications, as CO2 is chemically inert and non-toxic; in addition, it allows for an easy tailoring of the pore structure through processing conditions. Biodegradable polymeric materials, despite their enormous advantages over petroleum-based materials, present some difficulties regarding their potential use in foaming, such as poor melt strength, slow crystallization rate, poor processability, low service temperature, low toughness, and high brittleness, which limits their field of application. Several strategies were developed to improve the melt strength, including the change in monomer composition and the use of chemical modifiers and chain extenders to extend the chain length or create a branched molecular structure, to increase the molecular weight and the viscosity of the polymer. The use of additives or fillers is also commonly used, as fillers can improve crystallization kinetics by acting as crystal-nucleating agents. Alternatively, biodegradable polymers can be blended with other biodegradable polymers to combine certain properties and to counteract certain limitations. This work therefore aims to provide the latest advances regarding the foaming of biodegradable polymers. It covers the main foaming techniques and their advances and reviews the uses of biodegradable polymers in foaming, focusing on the chemical changes of polymers that improve their foaming ability. Finally, the challenges as well as the main opportunities presented reinforce the market potential of the biodegradable polymer foam materials.
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Affiliation(s)
- Luis F. F. F. Gonçalves
- 3B’s Research Group, I3Bs–Research Institute on Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, AvePark, Parque de Ciência e Tecnologia, Zona Industrial da Gandra, Barco, 4805-017 Guimarães, Portugal;
- ICVS/3B’s—PT Government Associate Laboratory, Barco, 4805-017 Guimarães, Portugal
| | - Rui L. Reis
- 3B’s Research Group, I3Bs–Research Institute on Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, AvePark, Parque de Ciência e Tecnologia, Zona Industrial da Gandra, Barco, 4805-017 Guimarães, Portugal;
- ICVS/3B’s—PT Government Associate Laboratory, Barco, 4805-017 Guimarães, Portugal
| | - Emanuel M. Fernandes
- 3B’s Research Group, I3Bs–Research Institute on Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, AvePark, Parque de Ciência e Tecnologia, Zona Industrial da Gandra, Barco, 4805-017 Guimarães, Portugal;
- ICVS/3B’s—PT Government Associate Laboratory, Barco, 4805-017 Guimarães, Portugal
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3
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Faba S, Arrieta MP, Romero J, Agüero Á, Torres A, Martínez S, Rayón E, Galotto MJ. Biodegradable nanocomposite poly(lactic acid) foams containing carvacrol-based cocrystal prepared by supercritical CO 2 processing for controlled release in active food packaging. Int J Biol Macromol 2024; 254:127793. [PMID: 37926308 DOI: 10.1016/j.ijbiomac.2023.127793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 10/15/2023] [Accepted: 10/29/2023] [Indexed: 11/07/2023]
Abstract
Compounds derived from essential oils have been used in active packaging, but their volatility and degradability negatively affect stability and leads to high release rates. The present study aimed to develop PLA bionanocomposite foams loaded with carvacrol cocrystal by supercritical CO2 and its release into a food simulant for control release in food packaging. For this purpose, 4,4'-bipyridine was used as coformer and carvacrol as active agent. Cocrystallized closed cell foams were obtained using supercritical CO2 and were characterized in terms of their physicochemical and mechanical properties, and release kinetics to a D1 simulant were evaluated as well as the antioxidant ability. A better overall mechanical behavior due to the nanoclay promoting a higher interfacial adhesion with the polymeric matrix was revealed. A higher incorporation of carvacrol was observed in samples with higher C30B content. The incorporated cocrystals showed a decrease of one order of magnitude in the estimated effective diffusion coefficient of carvacrol and showed antioxidant activity. These results suggest that the nanocomposite foam containing carvacrol-based cocrystals could be used in active packaging systems with controlled release characteristics, especially with highly volatile compounds, and can be proposed for other fields such as biomedical applications.
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Affiliation(s)
- Simón Faba
- Packaging Innovation Center (LABEN), Department of Food Science and Technology, Faculty of Technology, Center for the Development of Nanoscience and Nanotechnology (CEDENNA), University of Santiago de Chile (USACH), Santiago 9170201, Chile.
| | - Marina P Arrieta
- Departamento de Ingeniería Química Industrial y del Medio Ambiente, Escuela Técnica Superior de Ingenieros Industriales, Universidad Politécnica de Madrid (ETSII-UPM), Calle José Gutiérrez Abascal 2, 28006 Madrid, Spain; Grupo de Investigación: Polímeros, Caracterización y Aplicaciones (POLCA), 28006 Madrid, Spain
| | - Julio Romero
- Laboratory of Membrane Separation Processes (LabProSeM), Department of Chemical Engineering and Bioprocesses, Engineering Faculty, University of Santiago de Chile (USACH), 9170201 Santiago, Chile
| | - Ángel Agüero
- Departamento de Ingeniería Química Industrial y del Medio Ambiente, Escuela Técnica Superior de Ingenieros Industriales, Universidad Politécnica de Madrid (ETSII-UPM), Calle José Gutiérrez Abascal 2, 28006 Madrid, Spain; Institut de Tecnologia de Materials (ITM), Universitat Politècnica de València (UPV), Plaza Ferrándiz y Carbonell 1, 03801 Alcoy, Spain
| | - Alejandra Torres
- Packaging Innovation Center (LABEN), Department of Food Science and Technology, Faculty of Technology, Center for the Development of Nanoscience and Nanotechnology (CEDENNA), University of Santiago de Chile (USACH), Santiago 9170201, Chile
| | - Sara Martínez
- Packaging Innovation Center (LABEN), Department of Food Science and Technology, Faculty of Technology, Center for the Development of Nanoscience and Nanotechnology (CEDENNA), University of Santiago de Chile (USACH), Santiago 9170201, Chile
| | - Emilio Rayón
- Institut de Tecnologia de Materials, Universitat Politècnica de València (UPV), Camino de Vera, s/n, Código Postal 46022 Valencia, Spain
| | - María José Galotto
- Packaging Innovation Center (LABEN), Department of Food Science and Technology, Faculty of Technology, Center for the Development of Nanoscience and Nanotechnology (CEDENNA), University of Santiago de Chile (USACH), Santiago 9170201, Chile.
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Wu M, Ren Q, Zhu X, Li W, Luo H, Wu F, Wang L, Zheng W, Cui P, Yi X. Super toughened blends of poly(lactic acid) and poly(butylene adipate-co-terephthalate) injection-molded foams via enhancing interfacial compatibility and cellular structure. Int J Biol Macromol 2023:125490. [PMID: 37348589 DOI: 10.1016/j.ijbiomac.2023.125490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 06/08/2023] [Accepted: 06/18/2023] [Indexed: 06/24/2023]
Abstract
Biodegradable poly(lactic acid) (PLA) foams have drawn increasing attention due to environmental challenges and petroleum crisis. However, it still remains a challenge to prepare PLA foams with fine cellular structures and high impact property, which significantly hinders its widespread application. Herein, phase interface-enhanced PLA/ poly(butylene adipate-co-terephthalate) (PBAT) blend foam, modified by a reactive compatibilizer through a simple reactive extrusion, was produced via a core-back foam injection molding technique. The obtained PLA blend foams displayed an impact strength as high as 49.1 kJ/m2, which was 9.3 and 6.4 times that of the unmodified PLA/PBAT blend and its corresponding foam, respectively. It proved that the interfacial adhesion and cell size both strongly affected the impact strength of injection-molded PLA/PBAT foams, and two major conclusions were proposed. First, enhancing interfacial adhesion could cause a brittle-tough transition of PLA/PBAT foams. Additionally, for foams with high interfacial adhesion, small cell size (<12 μm) was more favorable for the stretching of cells and extension of the whitened region in comparison with big cell size (cell size >60 μm), leading to the drastic toughening of PLA blends. This study provides a feasible, industrially scalable and practical strategy to prepare super toughened and fully biodegradable PLA materials.
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Affiliation(s)
- Minghui Wu
- Ningbo Key Lab of Polymer Materials, Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang Province 315201, PR China; Faculty of Science and Engineering, University of Nottingham Ningbo China, 199 Taikang East Road, Ningbo 315000, PR China
| | - Qian Ren
- Ningbo Key Lab of Polymer Materials, Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang Province 315201, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Xiuyu Zhu
- Ningbo Key Lab of Polymer Materials, Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang Province 315201, PR China
| | - Wanwan Li
- Ningbo Key Lab of Polymer Materials, Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang Province 315201, PR China
| | - Haibin Luo
- Ningbo Key Lab of Polymer Materials, Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang Province 315201, PR China
| | - Fei Wu
- Ningbo Key Lab of Polymer Materials, Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang Province 315201, PR China
| | - Long Wang
- Ningbo Key Lab of Polymer Materials, Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang Province 315201, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
| | - Wenge Zheng
- Ningbo Key Lab of Polymer Materials, Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang Province 315201, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Ping Cui
- Faculty of Science and Engineering, University of Nottingham Ningbo China, 199 Taikang East Road, Ningbo 315000, PR China
| | - Xiaosu Yi
- Faculty of Science and Engineering, University of Nottingham Ningbo China, 199 Taikang East Road, Ningbo 315000, PR China
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Pilarska AA, Marzec-Grządziel A, Paluch E, Pilarski K, Wolna-Maruwka A, Kubiak A, Kałuża T, Kulupa T. Biofilm Formation and Genetic Diversity of Microbial Communities in Anaerobic Batch Reactor with Polylactide (PLA) Addition. Int J Mol Sci 2023; 24:10042. [PMID: 37373189 DOI: 10.3390/ijms241210042] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 05/27/2023] [Accepted: 06/07/2023] [Indexed: 06/29/2023] Open
Abstract
In this paper, an anaerobic digestion (AD) study was conducted on confectionery waste with granular polylactide (PLA) as a cell carrier. Digested sewage sludge (SS) served as the inoculum and buffering agent of systems. This article shows the results of the analyses of the key experimental properties of PLA, i.e., morphological characteristics of the microstructure, chemical composition and thermal stability of the biopolymer. The evaluation of quantitative and qualitative changes in the genetic diversity of bacterial communities, performed using the state-of-the-art next generation sequencing (NGS) technique, revealed that the material significantly enhanced bacterial proliferation; however, it does not change microbiome biodiversity, as also confirmed via statistical analysis. More intense microbial proliferation (compared to the control sample, without PLA and not digested, CW-control, CW-confectionery waste) may be indicative of the dual role of the biopolymer-support and medium. Actinobacteria (34.87%) were the most abundant cluster in the CW-control, while the most dominant cluster in digested samples was firmicutes: in the sample without the addition of the carrier (CW-dig.) it was 68.27%, and in the sample with the addition of the carrier (CW + PLA) it was only 26.45%, comparable to the control sample (CW-control)-19.45%. Interestingly, the number of proteobacteria decreased in the CW-dig. sample (17.47%), but increased in the CW + PLA sample (39.82%) compared to the CW-control sample (32.70%). The analysis of biofilm formation dynamics using the BioFlux microfluidic system shows a significantly faster growth of the biofilm surface area for the CW + PLA sample. This information was complemented by observations of the morphological characteristics of the microorganisms using fluorescence microscopy. The images of the CW + PLA sample showed carrier sections covered with microbial consortia.
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Affiliation(s)
- Agnieszka A Pilarska
- Department of Hydraulic and Sanitary Engineering, Poznań University of Life Sciences, Piątkowska 94A, 60-649 Poznan, Poland
| | - Anna Marzec-Grządziel
- Department of Agriculture Microbiology, Institute of Soil Science and Plant Cultivation-State Research Institute, Czartoryskich 8, 24-100 Pulawy, Poland
| | - Emil Paluch
- Department of Microbiology, Faculty of Medicine, Wroclaw Medical University, Tytusa Chałubińskiego 4, 50-376 Wroclaw, Poland
| | - Krzysztof Pilarski
- Department of Biosystems Engineering, Poznań University of Life Sciences, Wojska Polskiego 50, 60-627 Poznan, Poland
| | - Agnieszka Wolna-Maruwka
- Department of Soil Science and Microbiology, Poznań University of Life Sciences, Szydłowska 50, 60-656 Poznan, Poland
| | - Adrianna Kubiak
- Department of Soil Science and Microbiology, Poznań University of Life Sciences, Szydłowska 50, 60-656 Poznan, Poland
| | - Tomasz Kałuża
- Department of Hydraulic and Sanitary Engineering, Poznań University of Life Sciences, Piątkowska 94A, 60-649 Poznan, Poland
| | - Tomasz Kulupa
- Department of Hydraulic and Sanitary Engineering, Poznań University of Life Sciences, Piątkowska 94A, 60-649 Poznan, Poland
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6
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Fang F, Niu D, Xu P, Liu T, Yang W, Wang Z, Li X, Ma P. A Quantitative Study on Branching Density Dependent Behavior of Polylactide Melt Strength. Macromol Rapid Commun 2023; 44:e2200858. [PMID: 36661258 DOI: 10.1002/marc.202200858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 12/29/2022] [Indexed: 01/21/2023]
Abstract
Polymer melt strength (MS) is strongly correlated with its molecular structure, while their relationship is not very clear yet. In this work, designable long-chain branched polylactide (LCB-PLA) is prepared in situ by using a tailor-made (methyl methacrylate)-co-(glycidyl methacrylate) copolymer (MG) with accurate number of reactive sites. A new concept of branching density (φ) in the LCB-PLA system is defined to quantitively study their relationship. Importantly, a critical point of φc = 5.5 mol/104 mol C is revealed for the first time, below which the zero-shear viscosity (η0 ) corresponding to MS increases slowly with a slope of Δη0 /Δφ = 1400, while it increases sharply above this critical point due to entanglement of neighboring LCB-PLA chains. Consequently, the MS of PLA increased by >100 times by optimizing the LCB structures while maintaining processibility. Therefore, this work provides a deeper understanding and feasible route in quantitative design of polymers with high(er) melt strength for some specialty applications.
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Affiliation(s)
- Fengna Fang
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, China
| | - Deyu Niu
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, China
| | - Pengwu Xu
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, China
| | - Tianxi Liu
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, China
| | - Weijun Yang
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, China
| | - Zhenyu Wang
- Institute of Environmental Processes and Pollution control, Jiangnan University, Wuxi, 214122, China
| | - Xiaona Li
- Institute of Environmental Processes and Pollution control, Jiangnan University, Wuxi, 214122, China
| | - Piming Ma
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, China
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7
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Preparation of versatile lignin-based adsorbent for the removal of organic dyes and its application in wound healing. J Mol Liq 2023. [DOI: 10.1016/j.molliq.2023.121566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
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8
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Pilarska AA, Bula K, Pilarski K, Adamski M, Wolna-Maruwka A, Kałuża T, Magda P, Boniecki P. Polylactide (PLA) as a Cell Carrier in Mesophilic Anaerobic Digestion-A New Strategy in the Management of PLA. MATERIALS (BASEL, SWITZERLAND) 2022; 15:8113. [PMID: 36431599 PMCID: PMC9697477 DOI: 10.3390/ma15228113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 11/10/2022] [Accepted: 11/13/2022] [Indexed: 06/16/2023]
Abstract
The management of waste polylactide (PLA) in various solutions of thermophilic anaerobic digestion (AD) is problematic and often uneconomical. This paper proposes a different approach to the use of PLA in mesophilic AD, used more commonly on the industrial scale, which consists of assigning the function of a microbial carrier to the biopolymer. The study involved the testing of waste wafers and waste wafers and cheese in a co-substrate system, combined with digested sewage sludge. The experiment was conducted on a laboratory scale, in a batch bioreactor mode. They were used as test samples and as samples with the addition of a carrier: WF-control and WFC-control; WF + PLA and WFC + PLA. The main objective of the study was to verify the impact of PLA in the granular (PLAG) and powder (PLAP) forms on the stability and efficiency of the process. The results of the analysis of physicochemical properties of the carriers, including the critical thermal analysis by differential scanning calorimetry (DSC), as well as the amount of cellular biomass of Bacillus amyloliquefaciens obtained in a culture with the addition of the tested PLAG and PLAP, confirmed that PLA can be an effective cell carrier in mesophilic AD. The addition of PLAG produced better results for bacterial proliferation than the addition of powdered PLA. The highest level of dehydrogenase activity was maintained in the WFC + PLAG system. An increase in the volume of the methane produced for the samples digested with the PLA granules carrier was registered in the study. It went up by c.a. 26% for WF, from 356.11 m3 Mg-1 VS (WF-control) to 448.84 m3 Mg-1 VS (WF + PLAG), and for WFC, from 413.46 m3 Mg-1 VS, (WFC-control) to 519.98 m3 Mg-1 VS (WFC + PLAG).
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Affiliation(s)
- Agnieszka A. Pilarska
- Department of Hydraulic and Sanitary Engineering, Poznań University of Life Sciences, Piątkowska 94A, 60-649 Poznan, Poland
| | - Karol Bula
- Institute of Materials Technology, Faculty of Mechanical Engineering, Poznan University of Technology, 60-965 Poznan, Poland
| | - Krzysztof Pilarski
- Department of Biosystems Engineering, Poznań University of Life Sciences, Wojska Polskiego 50, 60-627 Poznan, Poland
| | - Mariusz Adamski
- Department of Biosystems Engineering, Poznań University of Life Sciences, Wojska Polskiego 50, 60-627 Poznan, Poland
| | - Agnieszka Wolna-Maruwka
- Department of Soil Science and Microbiology, Poznań University of Life Sciences, Szydłowska 50, 60-656 Poznan, Poland
| | - Tomasz Kałuża
- Department of Hydraulic and Sanitary Engineering, Poznań University of Life Sciences, Piątkowska 94A, 60-649 Poznan, Poland
| | - Przemysław Magda
- Department of Wastewater Treatment, Aquanet S.A., Gdyńska 1, 61-477 Poznań, Poland
| | - Piotr Boniecki
- Department of Biosystems Engineering, Poznań University of Life Sciences, Wojska Polskiego 50, 60-627 Poznan, Poland
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9
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Spiridon I, Varganici CD, Resmerita A, Simionescu TM. New ARBOFILL composites: preparation and characterization. POLYM-PLAST TECH MAT 2022. [DOI: 10.1080/25740881.2022.2084410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
Affiliation(s)
- Iuliana Spiridon
- Department of Natural Polymers, “Petru Poni” Institute of Macromolecular Chemistry, Iasi, Romania
| | - Cristian-Dragos Varganici
- Centre of Advanced Research in Bionanoconjugates and Biopolymers, “Petru Poni” Institute of Macromolecular Chemistry, Iasi, Romania
| | - Ana–Maria Resmerita
- Laboratory of Electroactive Polymers and Plasmochemistry, “Petru Poni” Institute of Macromolecular Chemistry, Iasi, Romania
| | - Tudor Mihai Simionescu
- Faculty of Material Science and Engineering, Gheorghe Asachi Technical University, Iasi, Romania
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10
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Liu YB, Peng LM, Bao RY, Yang MB, Yang W. Vitrimeric Polylactide by Two-step Alcoholysis and Transesterification during Reactive Processing for Enhanced Melt Strength. ACS APPLIED MATERIALS & INTERFACES 2022; 14:45966-45977. [PMID: 36166428 DOI: 10.1021/acsami.2c15595] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Because of its rather low melt strength, polylactide (PLA) has yet to fulfill its promise as advanced biobased and biodegradable foams to replace fossil-based polymer foams. In this work, PLA vitrimers were prepared by two-step reactive processing from commercial PLA thermoplastics, glycerol, and diphenylmethane diisocyanate (MDI) using Zn(II)-catalyzed addition and transesterification chemistry. The transesterification reaction of PLA and glycerol occurs with zinc acetate as the catalyst, and chain scission will take place due to the alcoholysis of the PLA chains by the free hydroxyl groups from the glycerol. Long-chain PLA with hydroxyl groups can be obtained and then cross-linked with MDI. Rheological analysis shows that the formed cross-linked network can significantly improve melt strength and promote strain hardening under extensional flow. PLA vitrimers still maintain the ability of thermoplastic processing via extrusion and compression. The enhanced melt strength and the rearrangement of network topology facilitate the foaming processing. An expansion ratio as large as 49.2-fold and microcellular foam with a uniform cell morphology can be obtained for PLA vitrimers with a gel fraction of 51.8% through a supercritical carbon dioxide foaming technique. This work provides a new way with the scale-up possibility to enhance the melt strength of PLA, and the broadened range of PLA applicability brought by PLA vitrimers is truly valuable in terms of the realization of a sustainable society.
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Affiliation(s)
- Yong-Bo Liu
- State Key Laboratory of Polymer Materials Engineering, College of Polymer Science and Engineering, Sichuan University, Chengdu 610065, Sichuan, China
| | - Li-Mei Peng
- State Key Laboratory of Polymer Materials Engineering, College of Polymer Science and Engineering, Sichuan University, Chengdu 610065, Sichuan, China
| | - Rui-Ying Bao
- State Key Laboratory of Polymer Materials Engineering, College of Polymer Science and Engineering, Sichuan University, Chengdu 610065, Sichuan, China
| | - Ming-Bo Yang
- State Key Laboratory of Polymer Materials Engineering, College of Polymer Science and Engineering, Sichuan University, Chengdu 610065, Sichuan, China
| | - Wei Yang
- State Key Laboratory of Polymer Materials Engineering, College of Polymer Science and Engineering, Sichuan University, Chengdu 610065, Sichuan, China
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11
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Wang B, Qi Z, Chen X, Sun C, Yao W, Zheng H, Liu M, Li W, Qin A, Tan H, Zhang Y. Preparation and mechanism of lightweight wood fiber/poly(lactic acid) composites. Int J Biol Macromol 2022; 217:792-802. [PMID: 35902018 DOI: 10.1016/j.ijbiomac.2022.07.101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 06/27/2022] [Accepted: 07/13/2022] [Indexed: 11/26/2022]
Abstract
The high density and poor thermal insulation of traditional wood-plastic composites limited the application in the field of building materials. In this paper, wood fiber (WF) and PLA were used as raw materials and azodicarbonamide was used as the foaming agent. Lightweight WF/PLA composites were prepared by the hot-pressing foaming method, aiming to obtain renewable, low-density material with high strength-to-weight ratio and thermal insulation performance. The results showed that after adding 20 % WF into PLA, the cell morphology was excellent and the cell size was uniform. The magnification reached the minimum value of 0.36 g/cm3 and the foaming magnification was 3.42 times. The impact strength and compressive strength were 3.16 kJ/m3 and 4.12 MPa, its comprehensive mechanical properties were outstanding. The thermal conductivity of foamed materials was 0.110-0.148 (W/m·K), which was significantly lower than that of unfoamed materials and common wood. Its excellent mechanical properties and thermal insulation can be suitable for application in the construction field to replace traditional wood.
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Affiliation(s)
- Baiwang Wang
- Engineering Research Center of Advanced Wooden Materials, Ministry of Education, Harbin 150040, China; Key Laboratory of Bio-Based Material Science and Technology, Northeast Forestry University, Ministry of Education, Harbin 150040, China
| | - Zhongyu Qi
- Engineering Research Center of Advanced Wooden Materials, Ministry of Education, Harbin 150040, China; Key Laboratory of Bio-Based Material Science and Technology, Northeast Forestry University, Ministry of Education, Harbin 150040, China
| | - Xiaojian Chen
- Engineering Research Center of Advanced Wooden Materials, Ministry of Education, Harbin 150040, China; Key Laboratory of Bio-Based Material Science and Technology, Northeast Forestry University, Ministry of Education, Harbin 150040, China
| | - Ce Sun
- Engineering Research Center of Advanced Wooden Materials, Ministry of Education, Harbin 150040, China; Key Laboratory of Bio-Based Material Science and Technology, Northeast Forestry University, Ministry of Education, Harbin 150040, China
| | - Wenrui Yao
- Engineering Research Center of Advanced Wooden Materials, Ministry of Education, Harbin 150040, China; Key Laboratory of Bio-Based Material Science and Technology, Northeast Forestry University, Ministry of Education, Harbin 150040, China
| | - Hao Zheng
- Engineering Research Center of Advanced Wooden Materials, Ministry of Education, Harbin 150040, China; Key Laboratory of Bio-Based Material Science and Technology, Northeast Forestry University, Ministry of Education, Harbin 150040, China
| | - Mengyao Liu
- Engineering Research Center of Advanced Wooden Materials, Ministry of Education, Harbin 150040, China; Key Laboratory of Bio-Based Material Science and Technology, Northeast Forestry University, Ministry of Education, Harbin 150040, China
| | - Wenlong Li
- Engineering Research Center of Advanced Wooden Materials, Ministry of Education, Harbin 150040, China; Key Laboratory of Bio-Based Material Science and Technology, Northeast Forestry University, Ministry of Education, Harbin 150040, China
| | - Aihang Qin
- Engineering Research Center of Advanced Wooden Materials, Ministry of Education, Harbin 150040, China; Key Laboratory of Bio-Based Material Science and Technology, Northeast Forestry University, Ministry of Education, Harbin 150040, China
| | - Haiyan Tan
- Engineering Research Center of Advanced Wooden Materials, Ministry of Education, Harbin 150040, China; Key Laboratory of Bio-Based Material Science and Technology, Northeast Forestry University, Ministry of Education, Harbin 150040, China
| | - Yanhua Zhang
- Engineering Research Center of Advanced Wooden Materials, Ministry of Education, Harbin 150040, China; Key Laboratory of Bio-Based Material Science and Technology, Northeast Forestry University, Ministry of Education, Harbin 150040, China.
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12
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Chai J, Wang G, Zhang A, Dong G, Li S, Zhao J, Zhao G. Microcellular injection molded lightweight and tough poly (L-lactic acid)/in-situ polytetrafluoroethylene nanocomposite foams with enhanced surface quality and thermally-insulating performance. Int J Biol Macromol 2022; 215:57-66. [PMID: 35718146 DOI: 10.1016/j.ijbiomac.2022.06.091] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Revised: 06/11/2022] [Accepted: 06/11/2022] [Indexed: 01/13/2023]
Abstract
High-performance microcellular polymer foams have been widely used all over the world, while the excessive usage of petroleum-based polymers caused serious environmental problems. As the eco-friendly awareness is increasing significantly, poly (L-lactic acid) (PLLA), as a typical biomass polymer, has gradually attracted widespread attention. However, the slow crystallization and poor melt strength of PLLA lead to low foaming ability and thus limiting its industrial applications. Herein, a novel and scalable strategy by coupling in-situ fibrillation and mold-opening microcellular injection molding (MOMIM) was developed to fabricate lightweight and tough PLLA/polytetrafluoroethylene (PTFE) foams. Thanks to the reticulated in-situ PTFE nanofibrils with a diameter of 100-200 nm, the crystallization and viscoelasticity of PLLA were dramatically promoted, and further contributing to its foaming ability. The expansion ratio of the MOMIM PLLA/PTFE foam was increased by 86 % compared with the regular microcellular injection molded (RMIM) PLLA foam. Moreover, the lower foam density and the toughening effect of PTFE nanofibrils resulted in the outstanding ductility of the PLLA/PTFE foams, whose tensile elongation, flexural strength, and impact strength were maximally increased by 52 %, 28 %, and 48 %, compared with PLLA foams. More importantly, the thermally-insulating performance and surface quality of PLLA/PTFE foams were also greatly improved.
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Affiliation(s)
- Jialong Chai
- Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education), Shandong University, Jinan, Shandong 250061, China
| | - Guilong Wang
- Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education), Shandong University, Jinan, Shandong 250061, China; School of Mechanical & Vehicle Engineering, Linyi University, Linyi, Shandong 276005, China.
| | - Aimin Zhang
- Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education), Shandong University, Jinan, Shandong 250061, China
| | - Guiwei Dong
- Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education), Shandong University, Jinan, Shandong 250061, China; State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, Shanghai 201620, China
| | - Shuai Li
- School of Mechanical & Vehicle Engineering, Linyi University, Linyi, Shandong 276005, China
| | - Jinchuan Zhao
- Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education), Shandong University, Jinan, Shandong 250061, China.
| | - Guoqun Zhao
- Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education), Shandong University, Jinan, Shandong 250061, China
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13
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Yang J, Xie J, Ji K, Wang X, Jiao X, Xu Z, Zhao P. Microcellular injection molding of polyether-ether-ketone. POLYMER 2022. [DOI: 10.1016/j.polymer.2022.124866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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14
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A facile strategy for preparation of strong tough poly(lactic acid) foam with a unique microfibrillated bimodal micro/nano cellular structure. Int J Biol Macromol 2022; 199:264-274. [PMID: 34999040 DOI: 10.1016/j.ijbiomac.2021.12.187] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 12/12/2021] [Accepted: 12/29/2021] [Indexed: 12/13/2022]
Abstract
This work reports the design and fabrication of strong tough poly(lactic acid) (PLA) foam by combining pressure-induced-flow (PIF) processing with supercritical CO2 foaming. PIF processing widened the foaming window of PLA to 40-120 °C, while supercritical CO2 foaming released the undesired internal stress of PLA samples with PIF processing (P-PLA). The prepared PLA foams displayed a unique microfibrillated bimodal micro/nano cellular structure which is strongly affected by saturation temperature (Ts). Both micron and nano cells showed decreasing cells size and increasing cell density as Ts elevated. The orientation factor as well as internal stress of PLA foams decreased with increased Ts. Compared with P-PLA samples, PLA foam prepared at Ts of 40 °C showed negligible reduction of orientation from 0.45 to 0.41 and release of internal stress characterized by the rightward shift of Raman peak (stretching vibration of CO bond from 1763 to 1766 cm-1). Furthermore, PLA foam prepared at Ts of 40 °C presented excellent impact strength (32.3 kJ/m2), tensile strength (42.0 MPa), and ductility (14.2%). The combination of PIF processing and supercritical CO2 foaming provides a facile and effective method to prepare strong tough PLA foam that has immense potential in biomedical, aerospace, automotive, and other structural applications.
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15
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Liu W, Wu X, Chen X, Liu S, Zhang C. Flexibly Controlling the Polycrystallinity and Improving the Foaming Behavior of Polylactic Acid via Three Strategies. ACS OMEGA 2022; 7:6248-6260. [PMID: 35224387 PMCID: PMC8867551 DOI: 10.1021/acsomega.1c06777] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 01/27/2022] [Indexed: 06/14/2023]
Abstract
Controlling foamability plays the central role in preparing PLA foams with high performances. To achieve this, chain extension was often used to improve the rheological property of PLA resins; however, despite the availability of this approach, it often deteriorates the biodegradability of PLA and greatly increases the processing cost and complexity. Hence, we reported a special crystallization induction method to design PLA foams with a tunable cellular structure and a high expansion ratio. A novel crystallization-promoting agent combination (D-sorbitol, CO2, and phenylphosphonic acid zinc salt) was used to induce PLA to enhance the chain interaction force and chain mobility and to provide crystallization templets. A series of PLAs with tunable stereocomplex (Sc)/α crystallinity and rapid non-isothermal crystallization ability were obtained. The effect of various crystallization properties on the foaming behavior of PLA was studied. The results demonstrated that proper crystallization conditions (a small spherulite size, a crystallinity of 6%, and rapid crystallization ability) could virtually contribute to the optimized cellular structure with the highest cell density of 4.36 × 106 cell/cm3. When the Sc crystallinity was above 10%, PLA had a superior foamability, which thereby resulted in a high foaming expansion ratio of 16.2. A variety of cellular morphologies of PLA foams could be obtained by changing the foaming temperature and the crystallization property. The proposed crystallization-induced approach provided a useful method for controlling the cellular structure and the performances of the PLA foams.
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16
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Standau T, Nofar M, Dörr D, Ruckdäschel H, Altstädt V. A Review on Multifunctional Epoxy-Based Joncryl® ADR Chain Extended Thermoplastics. POLYM REV 2021. [DOI: 10.1080/15583724.2021.1918710] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Tobias Standau
- Department of Polymer Engineering, University of Bayreuth, Bayreuth, Germany
| | - Mohammadreza Nofar
- Metallurgical and Materials Engineering, Department Faculty of Chemical and Metallurgical Engineering, Istanbul Technical University, Maslak, Istanbul, Turkey
- Polymer Science and Technology Program, Institute of Science and Technology, Istanbul Technical University, Maslak, Istanbul, Turkey
| | - Dominik Dörr
- Department of Polymer Engineering, University of Bayreuth, Bayreuth, Germany
| | - Holger Ruckdäschel
- Department of Polymer Engineering, University of Bayreuth, Bayreuth, Germany
| | - Volker Altstädt
- Department of Polymer Engineering, University of Bayreuth, Bayreuth, Germany
- Bavarian Polymer Institute and Bayreuth Institute of Macromolecular Research, University of Bayreuth, Bayreuth, Germany
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17
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Liu W, Wu X, Ou Y, Liu H, Zhang C. Electrically conductive and light-weight branched polylactic acid-based carbon nanotube foams. E-POLYMERS 2021. [DOI: 10.1515/epoly-2021-0013] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Abstract
In spite of the high electrical conductivity of carbon nanotube (CNT), its tendency to aggregate and expensive cost in fabricating aerogel, foams, and porous materials remains a problem. Therefore, we described a simple and feasible way to design light-weight, high electrically conductive, and cost-efficient polylactic acid (PLA)/CNT foams. The branched PLA (BPLA) resin with excellent melt elasticity and foamability was induced by nucleophilic ring-opening reaction of epoxy-based acrylic/styrene copolymer and PLA. After that, BPLA/CNT composites and foams were prepared by melt-mixing and supercritical carbon dioxide foaming technology, respectively. The thermal, electrical, and foaming properties were studied. The resultant BPLA/CNT foam possessed a low density of 0.174 g/cm3 and high crystallinity of 3.03%. An improvement of the oriented structure of CNT induced by cell growth in BPLA matrix increased the conductivity of the foam up to 3.51 × 104 Ω/m. The proposed foaming materials provided a way for designing and preparing high performance CNT products.
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Affiliation(s)
- Wei Liu
- School of Materials and Energy Engineering, Guizhou Institute of Technology , Guiyang 550003 , China
| | - Xian Wu
- School of Materials and Energy Engineering, Guizhou Institute of Technology , Guiyang 550003 , China
| | - Yangjia Ou
- School of Materials and Energy Engineering, Guizhou Institute of Technology , Guiyang 550003 , China
| | - Hao Liu
- School of Materials and Energy Engineering, Guizhou Institute of Technology , Guiyang 550003 , China
| | - Chun Zhang
- School of Materials and Energy Engineering, Guizhou Institute of Technology , Guiyang 550003 , China
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18
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Mort R, Vorst K, Curtzwiler G, Jiang S. Biobased foams for thermal insulation: material selection, processing, modelling, and performance. RSC Adv 2021; 11:4375-4394. [PMID: 35424381 PMCID: PMC8694562 DOI: 10.1039/d0ra09287h] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Accepted: 12/09/2020] [Indexed: 01/17/2023] Open
Abstract
With the urgent need for the development of sustainable materials and a circular economy, a surge of research regarding biobased materials and associated processing methods has resulted in many experimental biobased foams. Although several biobased foams are already shown to have thermal and mechanical properties competitive with expanded polystyrene, there remains a fundamental knowledge gap leading to limited understanding of the principles that determine performance. This review outlines the progress in this burgeoning field, introducing materials selection and processing, comparing performance, examining efforts in modelling physical properties, and discusses challenges in applying models to real biobased systems. The focus is on low thermal conductivity, which is a critical property for temperature-controlled applications such as packaging for refrigerated/frozen foods, medications, and vaccines as well as building materials. Currently, the trend in the field is moving towards fully biobased and compostable foams, though partially biobased polyurethane foams remain the most consistent performers. To illustrate the foam structure–property relationship, thermal conductivity, cell size, and density data were compiled. Given the complexity of biobased foams, heat transfer models aid in identifying crucial variables. However, data relevant to the insulation capability of biobased foams is not fully reported in many references. To address this issue, we employed a dimensional analysis to fill the gaps, revealing a power law correlation between thermal conductivity and relative density. Our approach is not intended as a robust prediction technique, but rather a simple demonstration of how biobased foams data could be utilized to predict the most promising materials and methods. This review outlines the progress in biobased foams with a focus on low thermal conductivity. It introduces materials selection and processing, compares performance, examines modelling of physical properties, and discusses challenges in applying models to real systems.![]()
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Affiliation(s)
- Rebecca Mort
- Materials Science and Engineering, Iowa State University Ames Iowa 50011 USA .,Polymer and Food Protection Consortium, Iowa State University Ames Iowa 50011 USA
| | - Keith Vorst
- Food Science and Human Nutrition, Iowa State University Ames Iowa 50011 USA.,Polymer and Food Protection Consortium, Iowa State University Ames Iowa 50011 USA
| | - Greg Curtzwiler
- Food Science and Human Nutrition, Iowa State University Ames Iowa 50011 USA.,Polymer and Food Protection Consortium, Iowa State University Ames Iowa 50011 USA
| | - Shan Jiang
- Materials Science and Engineering, Iowa State University Ames Iowa 50011 USA .,Polymer and Food Protection Consortium, Iowa State University Ames Iowa 50011 USA
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19
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Vozniak I, Beloshenko V, Savchenko B, Voznyak A. Improvement of mechanical properties of polylactide by equal channel multiple angular extrusion. J Appl Polym Sci 2021. [DOI: 10.1002/app.49720] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Iurii Vozniak
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences Lodz Poland
| | - Victor Beloshenko
- Donetsk Institute for Physics and Engineering named after A.A. Galkin National Academy of Sciences of Ukraine Kyiv Ukraine
| | - Bogdan Savchenko
- Department of applied ecology, Technology of polymers and chemical fibers Kyiv National University of Technologies and Design Kyiv Ukraine
| | - Andrej Voznyak
- Department of General Technical Disciplines and Vocational Training Kryvyi Rih State Pedagogical University Kryvyi Rih Ukraine
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20
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Azdast T, Hasanzadeh R. Increasing cell density/decreasing cell size to produce microcellular and nanocellular thermoplastic foams: A review. J CELL PLAST 2020. [DOI: 10.1177/0021955x20959301] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Nowadays, polymeric foams have attracted particular attention in scientific and industrial societies due to their unique properties, such as high strength to weight ratio, excellent thermal and sound insulation, and low cost. Researchers have shown that the extraordinary properties of polymeric foams such as superior thermal insulation, can be achieved by increasing the cell density/decreasing the cell size. In this regard, firstly, the most important foaming processes, i.e. batch, extrusion, and injection molding are studied in the present research. Then, cell nucleation stage as the most crucial phenomenon for achieving high cell density/small cell size is investigated in detail. In the next step, the most important researches in the field of polymeric foams are introduced in which the largest cell densities/smallest cell sizes have been achieved. The investigations show that the most remarkable results (highest cell densities/smallest cell sizes) belong to the batch process. Also, the use of nucleating agents, increasing the solubility of blowing agent into the polymer, and the use of nanoparticles are the most efficient solutions to achieve microcellular and nanocellular structures.
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Affiliation(s)
- Taher Azdast
- Department of Mechanical Engineering, Faculty of Engineering, Urmia University, Urmia, Iran
| | - Rezgar Hasanzadeh
- Department of Mechanical Engineering, Faculty of Engineering, Urmia University, Urmia, Iran
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21
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Zhang X, Ding W, Chang E, Chen X, Chen J, Park CB, Shen C. Foaming Behaviors and Mechanical Properties of Injection-Molded Polylactide/Cotton-Fiber Composites. Ind Eng Chem Res 2020. [DOI: 10.1021/acs.iecr.0c03348] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Xiaoli Zhang
- School of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001, China
- Microcellular Plastics Manufacturing Laboratory, Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, Ontario M5S 3G8, Canada
| | - Weidan Ding
- Microcellular Plastics Manufacturing Laboratory, Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, Ontario M5S 3G8, Canada
| | - Eunse Chang
- Microcellular Plastics Manufacturing Laboratory, Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, Ontario M5S 3G8, Canada
| | - Xuefeng Chen
- China National Pulp and Paper Research Institute, Beijing 100102, China
| | - Jingbo Chen
- School of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001, China
| | - Chul B. Park
- Microcellular Plastics Manufacturing Laboratory, Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, Ontario M5S 3G8, Canada
| | - Changyu Shen
- School of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001, China
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22
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Villamil Jiménez JA, Le Moigne N, Bénézet JC, Sauceau M, Sescousse R, Fages J. Foaming of PLA Composites by Supercritical Fluid-Assisted Processes: A Review. Molecules 2020; 25:molecules25153408. [PMID: 32731388 PMCID: PMC7436275 DOI: 10.3390/molecules25153408] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 07/21/2020] [Accepted: 07/22/2020] [Indexed: 11/30/2022] Open
Abstract
Polylactic acid (PLA) is a well-known and commercially available biopolymer that can be produced from different sources. Its different characteristics generated a great deal of interest in various industrial fields. Besides, its use as a polymer matrix for foam production has increased in recent years. With the rise of technologies that seek to reduce the negative environmental impact of processes, chemical foaming agents are being substituted by physical agents, primarily supercritical fluids (SCFs). Currently, the mass production of low-density PLA foams with a uniform cell morphology using SCFs as blowing agents is a challenge. This is mainly due to the low melt strength of PLA and its slow crystallization kinetics. Among the different options to improve the PLA characteristics, compounding it with different types of fillers has great potential. This strategy does not only have foaming advantages, but can also improve the performances of the final composites, regardless of the implemented foaming process, i.e., batch, injection molding, and extrusion. In addition, the operating conditions and the characteristics of the fillers, such as their size, shape factor, and surface chemistry, play an important role in the final foam morphology. This article proposes a critical review on the different SCF-assisted processes and effects of operating conditions and fillers on foaming of PLA composites.
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Affiliation(s)
- Jennifer Andrea Villamil Jiménez
- Polymers Composites and Hybrids (PCH), IMT Mines Ales, 30100 Ales, France; (J.A.V.J.); (J.-C.B.)
- Centre RAPSODEE, IMT Mines Albi, CNRS, Université de Toulouse, 81013 Albi, France; (M.S.); (R.S.)
| | - Nicolas Le Moigne
- Polymers Composites and Hybrids (PCH), IMT Mines Ales, 30100 Ales, France; (J.A.V.J.); (J.-C.B.)
- Correspondence: (N.L.M.); (J.F.)
| | - Jean-Charles Bénézet
- Polymers Composites and Hybrids (PCH), IMT Mines Ales, 30100 Ales, France; (J.A.V.J.); (J.-C.B.)
| | - Martial Sauceau
- Centre RAPSODEE, IMT Mines Albi, CNRS, Université de Toulouse, 81013 Albi, France; (M.S.); (R.S.)
| | - Romain Sescousse
- Centre RAPSODEE, IMT Mines Albi, CNRS, Université de Toulouse, 81013 Albi, France; (M.S.); (R.S.)
| | - Jacques Fages
- Centre RAPSODEE, IMT Mines Albi, CNRS, Université de Toulouse, 81013 Albi, France; (M.S.); (R.S.)
- Correspondence: (N.L.M.); (J.F.)
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23
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Liu W, Zhu X, Gao H, Su X, Wu X. Preparation and characterization of PLA foam chain extended through grafting octa(epoxycyclohexyl) POSS onto carbon nanotubes. CELLULAR POLYMERS 2020. [DOI: 10.1177/0262489320912521] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Improving foamability of poly (lactic acid) (PLA) resin is a key issue for its critical foaming applications with high-performance and ultralow density. However, owing to the rheological nature of linear PLA chain structure with relatively low molecular weight, the overall foamability of PLA resin cannot meet the processing requirements of foaming purpose. Here, we describe a simple and versatile technique to prepare high foamability PLA resin by inducing chain extender through grafting octa(epoxycyclohexyl) polyhedral oligomeric silsesquioxanes (POSS) on carbon nanotubes (CNT). After the orderly assemble of the two nanoparticles, an obvious increase in melt elasticity of PLA is observed. The enhanced melt elasticity of PLA had a significant effect on controlling subsequent foaming behavior. Thus, a homogeneous and finer cellular morphology of PLA rigid foam was obtained with a proper content of CNT-POSS. Eventually, the expansion ratio of chain-extended PLA foam was 13 times higher than that of unmodified PLA foam. The proposed design methodology will potentially pave a way for designing and preparing high-performance PLA rigid foam products.
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Affiliation(s)
- Wei Liu
- School of Materials and Metallurgical Engineering, Guizhou Institute of Technology, Guiyang City, Guizhou Province, People’s Republic of China
| | - Xunxian Zhu
- School of Materials and Metallurgical Engineering, Guizhou Institute of Technology, Guiyang City, Guizhou Province, People’s Republic of China
| | - Hongxiang Gao
- School of Materials and Metallurgical Engineering, Guizhou Institute of Technology, Guiyang City, Guizhou Province, People’s Republic of China
| | - Xiangdong Su
- Key Laboratory of Light Metal Materials Processing Technology of Guizhou Province, Guizhou Institute of Technology, Guiyang, Guizhou, People’s Republic of China
| | - Xian Wu
- School of Materials and Metallurgical Engineering, Guizhou Institute of Technology, Guiyang City, Guizhou Province, People’s Republic of China
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24
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Lopresti F, Botta L, Scaffaro R, Bilello V, Settanni L, Gaglio R. Antibacterial biopolymeric foams: Structure–property relationship and carvacrol release kinetics. Eur Polym J 2019. [DOI: 10.1016/j.eurpolymj.2019.109298] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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25
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Jiang R, Chen Y, Yao S, Liu T, Xu Z, Park CB, Zhao L. Preparation and characterization of high melt strength thermoplastic polyester elastomer with different topological structure using a two-step functional group reaction. POLYMER 2019. [DOI: 10.1016/j.polymer.2019.121628] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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26
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Standau T, Zhao C, Murillo Castellón S, Bonten C, Altstädt V. Chemical Modification and Foam Processing of Polylactide (PLA). Polymers (Basel) 2019; 11:E306. [PMID: 30960290 PMCID: PMC6419231 DOI: 10.3390/polym11020306] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 02/06/2019] [Accepted: 02/07/2019] [Indexed: 11/16/2022] Open
Abstract
Polylactide (PLA) is known as one of the most promising biopolymers as it is derived from renewable feedstock and can be biodegraded. During the last two decades, it moved more and more into the focus of scientific research and industrial use. It is even considered as a suitable replacement for standard petroleum-based polymers, such as polystyrene (PS), which can be found in a wide range of applications-amongst others in foams for packaging and insulation applications-but cause strong environmental issues. PLA has comparable mechanical properties to PS. However, the lack of melt strength is often referred to as a drawback for most foaming processes. One way to overcome this issue is the incorporation of chemical modifiers which can induce chain extension, branching, or cross-linking. As such, a wide variety of substances were studied in the literature. This work should give an overview of the most commonly used chemical modifiers and their effects on rheological, thermal, and foaming behavior. Therefore, this review article summarizes the research conducted on neat and chemically modified PLA foamed with the conventional foaming methods (i.e., batch foaming, foam extrusion, foam injection molding, and bead foaming).
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Affiliation(s)
- Tobias Standau
- Depatment of Polymer Engineering, University Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany.
| | - Chunjing Zhao
- Depatment of Polymer Engineering, University Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany.
| | - Svenja Murillo Castellón
- Institut für Kunststofftechnik, University of Stuttgart, Pfaffenwaldring 32, 70569 Stuttgart, Germany.
| | - Christian Bonten
- Institut für Kunststofftechnik, University of Stuttgart, Pfaffenwaldring 32, 70569 Stuttgart, Germany.
| | - Volker Altstädt
- Depatment of Polymer Engineering, University Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany.
- Bavarian Polymer Institute and Bayreuth Institute of Macromolecular Research, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany.
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Castillo C, Nesic A, Urra N, Maldonado A. Influence of thermoplasticized starch on physical-chemical properties of new biodegradable carriers intended for forest industry. Int J Biol Macromol 2019; 122:924-929. [PMID: 30412758 DOI: 10.1016/j.ijbiomac.2018.11.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 08/02/2018] [Accepted: 11/05/2018] [Indexed: 10/27/2022]
Abstract
In this work, the influence of different concentrations of thermoplasticized starch on thermal, mechanical, biodegradation and phytotoxic properties of biodegradable blend carrier composed of poly(lactic acid) and poly(butylene adipate‑co‑terephtalate) was investigated. The results showed that the addition of poly(butylene adipate‑co‑terephtalate) increased elasticity of PLA materials, whereas the presence of thermoplasticized starch promoted higher biodegradation rate of the investigated materials. Moreover, the prepared materials did not show phytotoxic effect on plant, thus proving potential application in forest industry as a biodegradable carrier for multiplication of plants.
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Affiliation(s)
- Catalina Castillo
- University of Concepcion, Technological Development Unit, Concepcion, Chile
| | - Aleksandra Nesic
- University of Concepcion, Technological Development Unit, Concepcion, Chile; Univeristy of Belgrade, Vinca Institute for Nuclear Sciences, Belgrade, Serbia.
| | - Nestor Urra
- University of Concepcion, Technological Development Unit, Concepcion, Chile
| | - Alvaro Maldonado
- University of Concepcion, Technological Development Unit, Concepcion, Chile
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Poly (lactic acid) blends: Processing, properties and applications. Int J Biol Macromol 2018; 125:307-360. [PMID: 30528997 DOI: 10.1016/j.ijbiomac.2018.12.002] [Citation(s) in RCA: 269] [Impact Index Per Article: 44.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 11/29/2018] [Accepted: 12/01/2018] [Indexed: 11/21/2022]
Abstract
Poly (lactic acid) or polylactide (PLA) is a commercial biobased, biodegradable, biocompatible, compostable and non-toxic polymer that has competitive material and processing costs and desirable mechanical properties. Thereby, it can be considered favorably for biomedical applications and as the most promising substitute for petroleum-based polymers in a wide range of commodity and engineering applications. However, PLA has some significant shortcomings such as low melt strength, slow crystallization rate, poor processability, high brittleness, low toughness, and low service temperature, which limit its applications. To overcome these limitations, blending PLA with other polymers is an inexpensive approach that could also tailor the final properties of PLA-based products. During the last two decades, researchers investigated the synthesis, processing, properties, and development of various PLA-based blend systems including miscible blends of poly l-lactide (PLLA) and poly d-lactide (PDLA), which generate stereocomplex crystals, binary immiscible/miscible blends of PLA with other thermoplastics, multifunctional ternary blends using a third polymer or fillers such as nanoparticles, as well as PLA-based blend foam systems. This article reviews all these investigations and compares the syntheses/processing-morphology-properties interrelationships in PLA-based blends developed so far for various applications.
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Mao H, He B, Guo W, Hua L, Yang Q. Effects of Nano-CaCO₃ Content on the Crystallization, Mechanical Properties, and Cell Structure of PP Nanocomposites in Microcellular Injection Molding. Polymers (Basel) 2018; 10:E1160. [PMID: 30961085 PMCID: PMC6403877 DOI: 10.3390/polym10101160] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 10/07/2018] [Accepted: 10/15/2018] [Indexed: 12/02/2022] Open
Abstract
Using supercritical nitrogen as the physical foaming agent, microcellular polypropylene (PP) nanocomposites were prepared in microcellular injection molding. The main purpose of this work is to study effects of content of nano-CaCO₃ on the crystallization, mechanical properties, and cell structure of PP nanocomposites in microcellular injection molding. The results show that adding nano-CaCO₃ to PP could improve its mechanical properties and cell structure. The thermal stability and crystallinity enhances with increase of nano-CaCO₃. As a bubble nucleating agent, adding nano-CaCO₃ to PP improves the cell structure in both the parallel sections and vertical sections. The mechanical properties increase first and then decrease with increase of nano-CaCO₃. The mechanical properties are affected by the cell structure, as well. The mechanical properties and cell structure are optimum when the content of nano-CaCO₃ is 6 wt %.
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Affiliation(s)
- Huajie Mao
- School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China.
- Hubei Key Laboratory of Advanced Technology for Automotive Components, Wuhan University of Technology, Wuhan 430070, China.
- Hubei Collaborative Innovation Center for Automotive Components Technology, Wuhan 430070, China.
| | - Bo He
- School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China.
- Hubei Key Laboratory of Advanced Technology for Automotive Components, Wuhan University of Technology, Wuhan 430070, China.
- Hubei Collaborative Innovation Center for Automotive Components Technology, Wuhan 430070, China.
| | - Wei Guo
- Hubei Key Laboratory of Advanced Technology for Automotive Components, Wuhan University of Technology, Wuhan 430070, China.
- Hubei Collaborative Innovation Center for Automotive Components Technology, Wuhan 430070, China.
- School of Automotive Engineering, Wuhan University of Technology, Wuhan 430070, China.
| | - Lin Hua
- Hubei Key Laboratory of Advanced Technology for Automotive Components, Wuhan University of Technology, Wuhan 430070, China.
- Hubei Collaborative Innovation Center for Automotive Components Technology, Wuhan 430070, China.
- School of Automotive Engineering, Wuhan University of Technology, Wuhan 430070, China.
| | - Qing Yang
- Hubei Key Laboratory of Advanced Technology for Automotive Components, Wuhan University of Technology, Wuhan 430070, China.
- Hubei Collaborative Innovation Center for Automotive Components Technology, Wuhan 430070, China.
- School of Automotive Engineering, Wuhan University of Technology, Wuhan 430070, China.
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Li B, Zhao G, Wang G, Zhang L, Gong J. Fabrication of high-expansion microcellular PLA foams based on pre-isothermal cold crystallization and supercritical CO2 foaming. Polym Degrad Stab 2018. [DOI: 10.1016/j.polymdegradstab.2018.08.009] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Role of high-density polyethylene in the crystallization behaviors, rheological property, and supercritical CO2 foaming of poly (lactic acid). Polym Degrad Stab 2017. [DOI: 10.1016/j.polymdegradstab.2017.11.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Chen P, Wang W, Wang Y, Yu K, Zhou H, Wang X, Mi J. Crystallization-induced microcellular foaming of poly (lactic acid) with high volume expansion ratio. Polym Degrad Stab 2017. [DOI: 10.1016/j.polymdegradstab.2017.08.022] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Wang Y, Song Y, Du J, Xi Z, Wang Q. Preparation of Desirable Porous Cell Structure Polylactide/Wood Flour Composite Foams Assisted by Chain Extender. MATERIALS 2017; 10:ma10090999. [PMID: 28846604 PMCID: PMC5615654 DOI: 10.3390/ma10090999] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 08/23/2017] [Accepted: 08/23/2017] [Indexed: 11/16/2022]
Abstract
Polylactide (PLA)/wood flour composite foam were prepared through a batch foaming process. The effect of the chain extender on the crystallization behavior and dynamic rheological properties of the PLA/wood flour composites were investigated as well as the crystal structure and cell morphology of the composite foams. The incorporation of the chain extender enhanced the complex viscosity and storage modulus of PLA/wood flour composites, indicating the improved melt elasticity. The chain extender also led to a decreased crystallization rate and final crystallinity of PLA/wood flour composites. With an increasing chain extender content, a finer and more uniform cell structure was formed, and the expansion ratio of PLA/wood flour composite foams was much higher than without the chain extender. Compared to the unfoamed composites, the crystallinity of the foamed PLA/wood flour composites was improved and the crystal was loosely packed. However, the new crystalline form was not evident.
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Affiliation(s)
- Youyong Wang
- Key Laboratory of Bio-Based Material Science and Technology (Ministry of Education), Northeast Forestry University, Harbin 150040, China.
| | - Yongming Song
- Key Laboratory of Bio-Based Material Science and Technology (Ministry of Education), Northeast Forestry University, Harbin 150040, China.
| | - Jun Du
- Key Laboratory of Bio-Based Material Science and Technology (Ministry of Education), Northeast Forestry University, Harbin 150040, China.
| | - Zhenhao Xi
- State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China.
| | - Qingwen Wang
- College of Materials and Energy, South China Agricultural University, Guangzhou 510642, China.
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Li S, He G, Liao X, Park CB, Yang Q, Li G. Introduction of a long-chain branching structure by ultraviolet-induced reactive extrusion to improve cell morphology and processing properties of polylactide foam. RSC Adv 2017. [DOI: 10.1039/c6ra26457c] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Long-chain branching structure introduced by UV-induced reactive extrusion could widen its foaming processing window.
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Affiliation(s)
- Shaojie Li
- College of Polymer Science and Engineering
- State Key Laboratory of Polymer Materials Engineering
- Sichuan University
- Chengdu
- China
| | - Guangjian He
- The Key Laboratory of Polymer Processing Engineering of Ministry of Education
- National Engineering Research Center of Novel Equipment for Polymer Processing
- South China University of Technology
- Guangzhou 510640
- China
| | - Xia Liao
- College of Polymer Science and Engineering
- State Key Laboratory of Polymer Materials Engineering
- Sichuan University
- Chengdu
- China
| | - Chul B. Park
- College of Polymer Science and Engineering
- State Key Laboratory of Polymer Materials Engineering
- Sichuan University
- Chengdu
- China
| | - Qi Yang
- College of Polymer Science and Engineering
- State Key Laboratory of Polymer Materials Engineering
- Sichuan University
- Chengdu
- China
| | - Guangxian Li
- College of Polymer Science and Engineering
- State Key Laboratory of Polymer Materials Engineering
- Sichuan University
- Chengdu
- China
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36
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Badia J, Ribes-Greus A. Mechanical recycling of polylactide, upgrading trends and combination of valorization techniques. Eur Polym J 2016. [DOI: 10.1016/j.eurpolymj.2016.09.005] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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