1
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Shou T, Wu Y, Yin D, Hu S, Wu S, Zhao X, Zhang L. In-situ self-crosslinking strategy for super-tough polylactic acid/ bio-based polyurethane blends. Int J Biol Macromol 2024; 261:129757. [PMID: 38281538 DOI: 10.1016/j.ijbiomac.2024.129757] [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: 09/17/2023] [Revised: 01/11/2024] [Accepted: 01/24/2024] [Indexed: 01/30/2024]
Abstract
As a bio-based degradable plastic, polylactic acid (PLA) is highly commercialized, but its inherent brittleness limits its widespread use. In-situ polymerization techniques are effective in improving the toughness of PLA. However, the enhancement of the toughening effect in polyurethanes (PUs) through in-situ self-crosslinking still requires improvement and heavily relies on petroleum-derived feedstocks in certain approaches. In this paper, 1,3-polypropanediol (PO3G) of bio-based origin rather than conventional polyols like polyethylene glycol (PEG) and poly propylene glycol (PPG) was used. PLA/PO3G-PU blends were prepared via an in-situ self-crosslinking strategy. With a notch impact and tensile strength of 55.95 kJ/m2 and 47.77 MPa (a retention rate of 68.9 % compared with pure PLA), respectively, PLA/PO3G-PU blends achieved a better balance between stiffness and toughness. This work provides a new option for PLA to achieve a stiffness-toughness balance and get rid of dependence on petrochemical resources.
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Affiliation(s)
- Tao Shou
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Yaowen Wu
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Dexian Yin
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Shikai Hu
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing, 100029, China; Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing, 10029, China.
| | - Sizhu Wu
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing, 100029, China; Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing, 10029, China
| | - Xiuying Zhao
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing, 100029, China; Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing, 10029, China.
| | - Liqun Zhang
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing, 100029, China; Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing, 10029, China; Institute of Emergent Elastomers, School of Materials Science and Engineering, South China University of Technology, Guangzhou, Guangdong, 510640, China
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2
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Shahdan D, Rosli NA, Chen RS, Ahmad S, Gan S. Strategies for strengthening toughened poly(lactic acid) blend via natural reinforcement with enhanced biodegradability: A review. Int J Biol Macromol 2023; 251:126214. [PMID: 37572810 DOI: 10.1016/j.ijbiomac.2023.126214] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 07/06/2023] [Accepted: 08/05/2023] [Indexed: 08/14/2023]
Abstract
The growing popularity of poly(lactic acid) (PLA) can be attributed to its favorable attributes, such as excellent compostability and robust mechanical properties. Two notable limitations of PLA are its high brittleness and slow biodegradation rate. Both of blending and copolymerization strategies work well to improve PLA's toughness while sacrificing the good tensile strength and modulus properties of PLA. One of the most effective and economical approaches to address this challenge is to incorporate natural reinforcing agents into the toughened PLA system, thereby simultaneously promoting the biodegradation rate of PLA. Nevertheless, the enhancement of tensile strength and modulus is accompanied by a notable decrease in elongation. Therefore, this review provides comprehensive information on the literature works related to the tensile strength, modulus, elongation at break and impact strength of the toughened PLA and its natural fiber reinforced composites. The impact of natural reinforcing agent on the tensile fracture mechanism as well as the synergistic effect on strengthening and toughening performance will be discussed. This review also focuses on the factors boosting the biodegradability of toughened PLA blend by using natural reinforcing fiber. Review presents potential future insights into the development of biodegradable and balanced strengthened-toughened PLA based advanced materials.
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Affiliation(s)
- Dalila Shahdan
- Department of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor, Malaysia
| | - Noor Afizah Rosli
- Department of Chemical Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia..
| | - Ruey Shan Chen
- Department of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor, Malaysia.
| | - Sahrim Ahmad
- Department of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor, Malaysia
| | - Sinyee Gan
- Malaysian Palm Oil Board, 6 Persiaran Institusi, Bandar Baru Bangi, 43000 Kajang, Selangor, Malaysia
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3
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Rohayzi NF, Katman HYB, Ibrahim MR, Norhisham S, Rahman NA. Potential Additives in Natural Rubber-Modified Bitumen: A Review. Polymers (Basel) 2023; 15:polym15081951. [PMID: 37112098 PMCID: PMC10142339 DOI: 10.3390/polym15081951] [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: 02/21/2023] [Revised: 04/05/2023] [Accepted: 04/14/2023] [Indexed: 04/29/2023] Open
Abstract
Conventional bitumen pavement is no longer suitable for handling increasing loads and weather variations, which cause road deterioration, Thus, the modification of bitumen has been suggested to counter this issue. This study provides a detailed assessment of various additives for modifying natural rubber-modified bitumen used in road construction. This work will focus on the use of additives with cup lump natural rubber (CLNR), which has recently started to gain attention among researchers, especially in rubber-producing countries such as Malaysia, Thailand and Indonesia. Furthermore, this paper aims to briefly review how the addition of additives or modifiers helps elevate the performance of bitumen by highlighting the significant properties of modified bitumen after the addition of modifiers. Moreover, the amount and method of application of each additive are discussed further to obtain the optimum value for future implementation. On the basis of past studies, this paper will review the utilisation of several types of additives, including polyphosphoric acid, Evotherm, mangosteen powder, trimethyl-quinoline and sulphur, and the application of xylene and toluene to ensure the homogeneity of the rubberised bitumen. Numerous studies were conducted to verify the performance of various types and compositions of additives, particularly in terms of physical and rheological properties. In general, additives enhance the properties of conventional bitumen. Future research should investigate CLNR because studies on its utilisation are limited.
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Affiliation(s)
- Nurul Farhana Rohayzi
- Department of Civil Engineering, College of Engineering, Universiti Tenaga Nasional, Putrajaya Campus, Jalan Ikram-Uniten, Kajang 43000, Malaysia
- Institute of Energy Infrastructure, Universiti Tenaga Nasional, Putrajaya Campus, Jalan Ikram-Uniten, Kajang 43000, Malaysia
| | - Herda Yati Binti Katman
- Department of Civil Engineering, College of Engineering, Universiti Tenaga Nasional, Putrajaya Campus, Jalan Ikram-Uniten, Kajang 43000, Malaysia
- Institute of Energy Infrastructure, Universiti Tenaga Nasional, Putrajaya Campus, Jalan Ikram-Uniten, Kajang 43000, Malaysia
| | - Mohd Rasdan Ibrahim
- Centre for Transportation Research, Department of Civil Engineering, Engineering Faculty, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Shuhairy Norhisham
- Department of Civil Engineering, College of Engineering, Universiti Tenaga Nasional, Putrajaya Campus, Jalan Ikram-Uniten, Kajang 43000, Malaysia
- Institute of Energy Infrastructure, Universiti Tenaga Nasional, Putrajaya Campus, Jalan Ikram-Uniten, Kajang 43000, Malaysia
| | - Noorhazlinda Abd Rahman
- School of Civil Engineering, Engineering Campus, Universiti Sains Malaysia, Penang 14300, Malaysia
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4
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Liu H, Zhao Y, Zheng Y, Chen J, Wang J, Gao G, Bai D. Toward ultra-tough and heat-resistant biodegradable polylactide/core-shell rubber blends by regulating the distribution of rubber particles with stereocomplex crystallites. Int J Biol Macromol 2023; 232:123422. [PMID: 36708887 DOI: 10.1016/j.ijbiomac.2023.123422] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/17/2023] [Accepted: 01/21/2023] [Indexed: 01/26/2023]
Abstract
Ultra-tough and heat-resistant poly(l-lactide)/core-shell rubber (PLLA/CSR) blends were fabricated by utilizing stereocomplex (SC) crystallites to effectively regulate the CSR distribution in PLLA matrix. Linear and 3-11 armed poly(d-lactide)s (PDLAs) were synthesized and then melt-mixed with PLLA/CSR blend. Interestingly, the incorporated PDLA chains could collaborate with PLLA chains to form dense SC crystallites network in PLLA/PDLA/CSR blends, thus inducing the CSR particles to transform from uniform distribution structure to network-like structure. With increasing the PDLA arm numbers, the size of CSR clusters in the network-like structure first increased and then decreased, and the continuity of the network-like structure first remained at a high level and then decreased obviously. The formation of CSR network-like structure could remarkably improve the impact strength of PLLA/PDLA/CSR blends without deteriorating their strength and modulus (compared with PLLA/CSR blend), and the CSR network-like structure with larger-sized CSR clusters and higher continuity could help obtain higher impact strength (78.3 kJ/m2). Moreover, the heat resistance of PLLA/PDLA/CSR blends could also be significantly improved (the highest Vicat softening temperature was 131 °C) by the SC crystallites network and CSR network-like structure. This work provides an effective strategy for controlling the rubber network-like morphology and thereby preparing high-performance PLLA materials.
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Affiliation(s)
- Huili Liu
- Chongqing Key Laboratory of Environmental Materials & Remediation Technologies, College of Chemistry and Environmental Engineering, Chongqing University of Arts and Sciences, Chongqing 402160, China
| | - Yaling Zhao
- Chongqing Key Laboratory of Environmental Materials & Remediation Technologies, College of Chemistry and Environmental Engineering, Chongqing University of Arts and Sciences, Chongqing 402160, China
| | - Yushan Zheng
- Chongqing Key Laboratory of Environmental Materials & Remediation Technologies, College of Chemistry and Environmental Engineering, Chongqing University of Arts and Sciences, Chongqing 402160, China
| | - Jianyang Chen
- Chongqing Key Laboratory of Environmental Materials & Remediation Technologies, College of Chemistry and Environmental Engineering, Chongqing University of Arts and Sciences, Chongqing 402160, China
| | - Jianchuan Wang
- School of Chemistry & Chemical Engineering, Chongqing University, Chongqing 400044, China
| | - Guangyong Gao
- SWS Hemodialysis Care Co., Ltd, Chongqing, Chongqing 401120, China
| | - Dongyu Bai
- Chongqing Key Laboratory of Materials Surface & Interface Science, School of Materials Science and Engineering, Chongqing University of Arts and Sciences, Chongqing 402160, China.
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5
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Chen X, Gao S, Yang L, Song J, Song T, Ling J, Shi M, Liu J, Wu X, Wang P. Highly toughened and heat-resistant poly(L-lactide)/polyvinylidene fluoride materials through simply interfacial interaction control via epoxy chain extender. Eur Polym J 2023. [DOI: 10.1016/j.eurpolymj.2023.111839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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6
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Design of biodegradable PLA/PBAT blends with balanced toughness and strength via interfacial compatibilization and dynamic vulcanization. POLYMER 2023. [DOI: 10.1016/j.polymer.2022.125620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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7
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Chen N, Peng C, Chang YC, Li X, Zhang Y, Liu H, Zhang S, Zhang P. Supertough poly(lactic acid)/bio-polyurethane blends fabricated by dynamic self-vulcanization of dual difunctional monomers. Int J Biol Macromol 2022; 222:1314-1325. [DOI: 10.1016/j.ijbiomac.2022.09.253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 09/27/2022] [Accepted: 09/27/2022] [Indexed: 11/05/2022]
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8
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Strengthening of polyamide 6 and isosorbide-containing copolyester immiscible blends by in-situ reactive compatibilization. POLYMER 2022. [DOI: 10.1016/j.polymer.2022.125597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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9
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Shen H, Hu Y, Lin Z, Meng F, Ju G. Mechanical Properties, Crystallization Behaviors and Phase Morphologies of PLA/GTR Blends by Reactive Compatibilization. MATERIALS (BASEL, SWITZERLAND) 2022; 15:7095. [PMID: 36295162 PMCID: PMC9605194 DOI: 10.3390/ma15207095] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 10/05/2022] [Accepted: 10/09/2022] [Indexed: 06/16/2023]
Abstract
Different ratios of Polylactic acid/Ground tire rubber (PLA/GTR) were prepared by melt blending and adding dicumyl peroxide (DCP) as a reactive compatibilizer. The compatibilizer could initiate a reaction between PLA and GTR to increase the compatibility and interfacial adhesion of the two phases, as indicated by Fourier transform infrared (FTIR) spectrometry and scanning electron microscopy (SEM). Adding the compatibilizer significantly improved the impact strength of the PLA/GTR blends without compromising the tensile strength. The elongation at the break and notched Izod impact strength of the blend increased by 61.8% and 150%, respectively, but there was only a 4.1% decline in tensile strength compared with the neat PLA. The plastic deformation on the impact fractured surface showed that the improvement of toughness could be attributed to the compatibilization initiated by DCP. Therefore, the improvement of the interfacial adhesion and compatibility of the two phases induced a brittle-ductile transition that occurred in the failure of blends. Moreover, the crystallinity of blends reached 40.5% without a further annealing treatment, which was nearly 24 times of the neat PLA, and the crystallization rate was enhanced simultaneously. These exciting findings suggest that compatibilization can provide a promising avenue for fabricating GTR-toughened PLA blends with balanced stiffness-toughness.
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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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Liu H, Chen N, Peng C, Zhang S, Liu T, Song P, Zhong G, Liu H. Diisocyanate-Induced Dynamic Vulcanization of Difunctional Fatty Acids toward Mechanically Robust PLA Blends with Enhanced Luminescence Emission. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c00674] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hongzhi Liu
- School of Materials Science and Engineering, NingboTech University, No. 1 Qianhu South Road, Ningbo 315100, P. R. China
- College of Engineering, Zhejiang A&F University, Lin′an, Hangzhou 311300, P. R. China
| | - Ning Chen
- College of Engineering, Zhejiang A&F University, Lin′an, Hangzhou 311300, P. R. China
| | - Changqing Peng
- School of Materials Science and Engineering, NingboTech University, No. 1 Qianhu South Road, Ningbo 315100, P. R. China
| | - Shuai Zhang
- School of Materials Science and Engineering, NingboTech University, No. 1 Qianhu South Road, Ningbo 315100, P. R. China
| | - Tuan Liu
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200240, P. R. China
| | - Pingan Song
- School of Agriculture and Environmental Science & Centre for Future Materials, University of Southern Queensland, Brisbane 4300, QLD, Australia
| | - Guolun Zhong
- School of Materials Science and Engineering, NingboTech University, No. 1 Qianhu South Road, Ningbo 315100, P. R. China
| | - Hao Liu
- School of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001, P. R. China
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12
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Shahroodi Z, Katbab AA. Preparation and characterization of peroxide‐based dynamically vulcanized thermoplastic elastomer of poly (lactic acid)/chloroprene rubber. POLYM ENG SCI 2022. [DOI: 10.1002/pen.25937] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Zahra Shahroodi
- Department of Polymer Engineering Amirkabir University of Technology (Tehran Polytechnic) Tehran Iran
| | - Ali Asghar Katbab
- Department of Polymer Engineering Amirkabir University of Technology (Tehran Polytechnic) Tehran Iran
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13
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Dadashi P, Babaei A, Abdolrasouli MH. Investigating the hydrolytic degradation of
PLA
/
PCL
/
ZnO
nanocomposites by using viscoelastic models. POLYM ENG SCI 2022. [DOI: 10.1002/pen.25893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Parsa Dadashi
- School of Chemical Engineering, College of Engineering, University of Tehran Tehran Iran
- Faculty of Engineering, Department of Polymer Engineering Golestan University Gorgan Iran
| | - Amir Babaei
- Faculty of Engineering, Department of Polymer Engineering Golestan University Gorgan Iran
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14
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Niu D, Xu P, Sun Z, Yang W, Dong W, Ji Y, Liu T, Du M, Lemstra PJ, Ma P. Superior toughened bio-compostable Poly(glycolic acid)-based blends with enhanced melt strength via selective interfacial localization of in-situ grafted copolymers. POLYMER 2021. [DOI: 10.1016/j.polymer.2021.124269] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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15
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Mostoni S, D’Arienzo M, Di Credico B, Armelao L, Rancan M, Dirè S, Callone E, Donetti R, Susanna A, Scotti R. Design of a Zn Single-Site Curing Activator for a More Sustainable Sulfur Cross-Link Formation in Rubber. Ind Eng Chem Res 2021; 60:10180-10192. [PMID: 34483477 PMCID: PMC8411846 DOI: 10.1021/acs.iecr.1c01580] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 06/23/2021] [Accepted: 06/24/2021] [Indexed: 11/29/2022]
Abstract
ZnO is a worldwide used activator for a rubber vulcanization process, which promotes fast curing kinetics and high cross-linking densities of rubber nanocomposites (NCs). However, its extended use together with leaching phenomena occurring during the production and life cycle of rubber products, especially tires, entails potential environmental risks, as ecotoxicity toward aquatic organisms. Pushed by this issue, a novel activator was developed, which introduces highly dispersed and active zinc species in the vulcanization process, reducing the amount of employed ZnO and keeping high the curing efficiency. The activator is constituted by Zn(II) single sites, anchored on the surface of SiO2 nanoparticles (NPs) through the coordination with functionalizing amino silane groups. It behaves as a double-function material, acting at the same time as a rubber reinforcing filler and a curing activator. The higher availability and reactivity of the single-site Zn(II) centers toward curative agents impart faster kinetics and higher efficiency to the vulcanization process of silica/isoprene NCs, compared to conventionally used ZnO activators. Moreover, the NCs show a high cross-linking degree and improved dynamic mechanical properties, despite the remarkably lower amount of zinc employed than that normally used for rubber composites in tires. Finally, the structural stability of Zn(II) single sites during the curing reactions and in the final materials may represent a turning point toward the elimination of zinc leaching phenomena.
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Affiliation(s)
- Silvia Mostoni
- Department
of Materials Science, INSTM, University
of Milano-Bicocca, Via R. Cozzi 55, Milano 20125, Italy
| | - Massimiliano D’Arienzo
- Department
of Materials Science, INSTM, University
of Milano-Bicocca, Via R. Cozzi 55, Milano 20125, Italy
| | - Barbara Di Credico
- Department
of Materials Science, INSTM, University
of Milano-Bicocca, Via R. Cozzi 55, Milano 20125, Italy
| | - Lidia Armelao
- Institute
of Condensed Matter Chemistry and Technologies for Energy, National Research Council of Italy, ICMATE-CNR, via Marzolo 1, Padua 35131, Italy
- Department
of Chemical Sciences, University of Padua, Via Marzolo 1, Padua 35131, Italy
- Department
of Chemical Sciences and Materials Technologies, National Research Council of Italy, DSCTM-CNR, Piazzale A. Moro 7, Rome 00185, Italy
| | - Marzio Rancan
- Institute
of Condensed Matter Chemistry and Technologies for Energy, National Research Council of Italy, ICMATE-CNR, via Marzolo 1, Padua 35131, Italy
| | - Sandra Dirè
- “Klaus
Müller” Magnetic Resonance Lab., Dept. of Industrial
Engineering, University of Trento, Via Sommarive 9, Trento 38123, Italy
| | - Emanuela Callone
- “Klaus
Müller” Magnetic Resonance Lab., Dept. of Industrial
Engineering, University of Trento, Via Sommarive 9, Trento 38123, Italy
| | | | | | - Roberto Scotti
- Department
of Materials Science, INSTM, University
of Milano-Bicocca, Via R. Cozzi 55, Milano 20125, Italy
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16
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Transesterification catalyzed via ferric chloride for fabricating Poly(lactic acid)/Poly(butylene adipate-co-terephthalate) blends with ultra-fast degradation and high toughness. POLYMER 2021. [DOI: 10.1016/j.polymer.2021.123927] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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17
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Poly (Lactic Acid)/Ground Tire Rubber Blends Using Peroxide Vulcanization. Polymers (Basel) 2021; 13:polym13091496. [PMID: 34066622 PMCID: PMC8124148 DOI: 10.3390/polym13091496] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 05/04/2021] [Accepted: 05/05/2021] [Indexed: 11/17/2022] Open
Abstract
Poly (Lactic Acid) (PLA)/Ground Tire Rubber (GTR) blends using Dicumyl peroxide (DCP) as a crosslinking agent were prepared with the following aims: propose a new route to recycle wastes rubber from the automotive industry and improve the toughness and impact strength of the inherently brittle bio-based PLA. The GTR were subjected to two types of grinding process (cryo- and dry ambient grinding). Swelling measurements revealed the grinding to be associated with a mechanical damage of the rubber chains, independently on the type of grinding or on the GTR size (from <400 µm to <63 µm). Moreover, the finest GTR contains the largest amount of reinforcing elements (carbon black, clay) that can be advantageously used in PLA/GTR blends. Indeed, the use of the finest cryo-grinded GTR in the presence of DCP showed the least decrease of the tensile strength (−30%); maintenance of the tensile modulus and the largest improvement of the strain at break (+80%), energy at break (+60%) and impact strength (+90%) as compared to the neat PLA. The results were attributed to the good dispersion of both fine GTR and clay particles into the PLA matrix. Moreover, a possible re-crosslinking of the GTR particles and/or co-crosslinking at PLA/GTR interface in presence of DCP is expected to contribute to such improved ductility and impact strength.
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