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Mathew MM, M G, Unnikrishnan G. Facile preparation and characterization of biodegradable and biocompatible UV shielding transdermal patches based on natural rubber latex- dextrin blends. Int J Biol Macromol 2024; 277:134183. [PMID: 39112113 DOI: 10.1016/j.ijbiomac.2024.134183] [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: 02/29/2024] [Revised: 07/23/2024] [Accepted: 07/25/2024] [Indexed: 08/23/2024]
Abstract
The physico-chemical and biological properties of natural rubber latex (NRL), entailing its biodegradability and biocompatibility, render it a promising material for various biomedical applications. This research explores the facile blending of NRL with dextrin in different compositions to investigate its potential as a prospective UV shielding transdermal patch for biomedical applications. The superior compatibility between the polymers after blending and the improved thermal stability have been established through FTIR, DSC, and TGA examinations, respectively. Optimization of blended polymers for compatibility, wettability, crystallinity, and static mechanical properties has been performed. Morphology characterization conducted via SEM and AFM techniques suggests a uniform morphology for the optimized blend system. The UV shielding ability of the blend has been confirmed by the evaluation of in-vitro UV shielding performance, UV protection factor (UPF), and the superior protection of the optimized system on living cells upon UV irradiation. The observed cell viability, swelling, erosion, porosity, hemocompatibility, and soil degradation properties suggest the NRL-DXT combination for the possible development of high-quality transdermal patches.
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Affiliation(s)
| | - Gopika M
- National Institute of Technology Calicut, Calicut P.O 673601, India
| | - G Unnikrishnan
- National Institute of Technology Calicut, Calicut P.O 673601, India.
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2
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Marques PAC, Guerra NB, Dos Santos LS, Mussagy CU, Pegorin Brasil GS, Burd BS, Su Y, da Silva Sasaki JC, Scontri M, de Lima Lopes Filho PE, Silva GR, Miranda MCR, Ferreira ES, Primo FL, Fernandes MA, Crotti AEM, He S, Forster S, Ma C, de Barros NR, de Mendonça RJ, Jucaud V, Li B, Herculano RD, Floriano JF. Natural rubber latex-based biomaterials for drug delivery and regenerative medicine: Trends and directions. Int J Biol Macromol 2024; 267:131666. [PMID: 38636755 DOI: 10.1016/j.ijbiomac.2024.131666] [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: 01/19/2024] [Revised: 03/23/2024] [Accepted: 04/15/2024] [Indexed: 04/20/2024]
Abstract
Natural Rubber Latex (NRL) has shown to be a promising biomaterial for use as a drug delivery system to release various bioactive compounds. It is cost-effective, easy to handle, biocompatible, and exhibits pro-angiogenic and pro-healing properties for both soft and hard tissues. NRL releases compounds following burst and sustained release kinetics, exhibiting first-order release kinetics. Moreover, its pore density can be adjusted for tailored kinetics profiles. In addition, biotechnological applications of NRL in amblyopia, smart mattresses, and neovaginoplasty have demonstrated success. This comprehensive review explores NRL's diverse applications in biotechnology and biomedicine, addressing challenges in translating research into clinical practice. Organized into eight sections, the review emphasizes NRL's potential in wound healing, drug delivery, and metallic nanoparticle synthesis. It also addresses the challenges in enhancing NRL's physical properties and discusses its interactions with the human immune system. Furthermore, examines NRL's potential in creating wearable medical devices and biosensors for neurological disorders. To fully explore NRL's potential in addressing important medical conditions, we emphasize throughout this review the importance of interdisciplinary research and collaboration. In conclusion, this review advances our understanding of NRL's role in biomedical and biotechnological applications, offering insights into its diverse applications and promising opportunities for future development.
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Affiliation(s)
- Paulo Augusto Chagas Marques
- Department of Chemical Engineering, Federal University of São Carlos, Rodovia Washington Luís, km 235, 13560-970 Sao Carlos, SP, Brazil
| | | | - Lindomar Soares Dos Santos
- Faculty of Philosophy, Sciences and Letters at Ribeirão Preto, University of São Paulo, 3900 Bandeirantes Avenue, 14.040-901 Ribeirão Preto, SP, Brazil
| | - Cassamo Ussemane Mussagy
- Escuela de Agronomía, Facultad de Ciencias Agronómicas y de los Alimentos, Pontificia Universidad Católica de Valparaíso, Chile
| | - Giovana Sant'Ana Pegorin Brasil
- Bioengineering & Biomaterials Group, São Paulo State University (UNESP), School of Pharmaceutical Sciences, Araraquara, SP, Brazil; São Paulo State University (UNESP), Post-Graduate Program in Biotechnology, Institute of Chemistry, 14800-903 Araraquara, SP, Brazil
| | - Betina Sayeg Burd
- Bioengineering & Biomaterials Group, São Paulo State University (UNESP), School of Pharmaceutical Sciences, Araraquara, SP, Brazil; São Paulo State University (UNESP), Post-Graduate Program in Biotechnology, Institute of Chemistry, 14800-903 Araraquara, SP, Brazil
| | - Yanjin Su
- Bioengineering & Biomaterials Group, São Paulo State University (UNESP), School of Pharmaceutical Sciences, Araraquara, SP, Brazil
| | - Josana Carla da Silva Sasaki
- Bioengineering & Biomaterials Group, São Paulo State University (UNESP), School of Pharmaceutical Sciences, Araraquara, SP, Brazil; São Paulo State University (UNESP), Post-Graduate Program in Biotechnology, Institute of Chemistry, 14800-903 Araraquara, SP, Brazil
| | - Mateus Scontri
- Bioengineering & Biomaterials Group, São Paulo State University (UNESP), School of Pharmaceutical Sciences, Araraquara, SP, Brazil
| | | | - Glaucio Ribeiro Silva
- Federal Institute of Education, Science, and Technology of Minas Gerais, s/n São Luiz Gonzaga Street, 35577-010 Formiga, Minas Gerais, Brazil
| | - Matheus Carlos Romeiro Miranda
- Institute of Environmental, Chemical and Pharmaceutical Sciences, Federal University of São Paulo (UNIFESP), Rua Prof. Artur Riedel, 275, 09972-270 Diadema, SP, Brazil
| | - Ernando Silva Ferreira
- State University of Feira de Santana (UEFS), Department of Physics, s/n Transnordestina Highway, 44036-900 Feira de Santana, BA, Brazil
| | - Fernando Lucas Primo
- Bionanomaterials and Bioengineering Group, Department of Biotechnology and Bioprocesses Engineering, São Paulo State University (UNESP), Faculty of Pharmaceutical Sciences, Araraquara, 14800-903, São Paulo, Brazil
| | - Mariza Aires Fernandes
- Bionanomaterials and Bioengineering Group, Department of Biotechnology and Bioprocesses Engineering, São Paulo State University (UNESP), Faculty of Pharmaceutical Sciences, Araraquara, 14800-903, São Paulo, Brazil
| | - Antônio Eduardo Miller Crotti
- Faculty of Philosophy, Sciences and Letters at Ribeirão Preto, University of São Paulo, 3900 Bandeirantes Avenue, 14.040-901 Ribeirão Preto, SP, Brazil
| | - Siqi He
- Terasaki Institute for Biomedical Innovation (TIBI), 11507 W Olympic Blvd, Los Angeles, CA 90064, USA
| | - Samuel Forster
- Terasaki Institute for Biomedical Innovation (TIBI), 11507 W Olympic Blvd, Los Angeles, CA 90064, USA
| | - Changyu Ma
- Terasaki Institute for Biomedical Innovation (TIBI), 11507 W Olympic Blvd, Los Angeles, CA 90064, USA; Autonomy Research Center for STEAHM (ARCS), California State University, Northridge, CA 91324, USA
| | - Natan Roberto de Barros
- Terasaki Institute for Biomedical Innovation (TIBI), 11507 W Olympic Blvd, Los Angeles, CA 90064, USA
| | - Ricardo José de Mendonça
- Department of Biochemistry, Pharmacology and Physiology, Federal University of Triângulo Mineiro (UFTM), Uberaba, Minas Gerais, Brazil
| | - Vadim Jucaud
- Terasaki Institute for Biomedical Innovation (TIBI), 11507 W Olympic Blvd, Los Angeles, CA 90064, USA
| | - Bingbing Li
- Terasaki Institute for Biomedical Innovation (TIBI), 11507 W Olympic Blvd, Los Angeles, CA 90064, USA; Autonomy Research Center for STEAHM (ARCS), California State University, Northridge, CA 91324, USA
| | - Rondinelli Donizetti Herculano
- Bioengineering & Biomaterials Group, São Paulo State University (UNESP), School of Pharmaceutical Sciences, Araraquara, SP, Brazil; Terasaki Institute for Biomedical Innovation (TIBI), 11507 W Olympic Blvd, Los Angeles, CA 90064, USA; Autonomy Research Center for STEAHM (ARCS), California State University, Northridge, CA 91324, USA.
| | - Juliana Ferreira Floriano
- School of Science, São Paulo State University (UNESP), 17033-360 Bauru, SP, Brazil; Bioengineering & Biomaterials Group, São Paulo State University (UNESP), School of Pharmaceutical Sciences, Araraquara, SP, Brazil; National Heart and Lung Institute, Imperial College London, SW7 2AZ London, UK.
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3
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Lipatova IM, Losev NV. The influence of the combined impact of shear stress and cavitation on the structure and properties of starch-natural rubber composite. Carbohydr Polym 2024; 330:121852. [PMID: 38368078 DOI: 10.1016/j.carbpol.2024.121852] [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: 11/13/2023] [Revised: 12/27/2023] [Accepted: 01/19/2024] [Indexed: 02/19/2024]
Abstract
In this article, we examined a high-performance, environmentally friendly method for producing composite films based on starch and natural rubber latex (NR). To increase the compatibility of the components, the casting dispersions were subjected to short-term (10 s) mechanical activation in a rotor-stator device. Using the rotational viscosimetry method, it was found that mechanical activation reduces the structuring degree and the effective viscosity of the casting dispersions. The composite films with the NR content of 0-30 % were characterized using optical and SEM microscopy, X-ray diffraction, tensile, and moisture resistance testing data. When the NR content increases from 0 to 30 %, the elongation at break increased by 570 % and 950 % for films obtained using mechanical activation and without it, respectively. The extremely high increase in film tensile strength (on average by 155 %) and the decrease in the NR extractability with toluene due to the use of mechanical activation indicate the possibility of mechanically induced formation of an in situ copolymer at the starch-NR interface. The developed method can be recommended for large-scale production of composite starch-based materials.
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Affiliation(s)
- I M Lipatova
- G.A. Krestov Institute of Solution Chemistry of the Russian Academy of Sciences, 1 Akademicheskaya St., Ivanovo 153045, Russia.
| | - N V Losev
- G.A. Krestov Institute of Solution Chemistry of the Russian Academy of Sciences, 1 Akademicheskaya St., Ivanovo 153045, Russia
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Taddei P, Di Foggia M, Zamparini F, Prati C, Gandolfi MG. Guttapercha Improves In Vitro Bioactivity and Dentin Remineralization Ability of a Bioglass Containing Polydimethylsiloxane-Based Root Canal Sealer. Molecules 2023; 28:7088. [PMID: 37894568 PMCID: PMC10609493 DOI: 10.3390/molecules28207088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 10/05/2023] [Accepted: 10/12/2023] [Indexed: 10/29/2023] Open
Abstract
Guttapercha (GP, trans-1,4-polyisoprene) is the most used tooth root filling material, and it must be used with an appropriate cement (typically a polydimethylsiloxane (PDMS)-based sealer) to ensure an adequate canal obturation. This study aimed to assess the bioactivity and dentin remineralization ability of a bioglass containing PDMS commercial endodontic sealer, BG-PDMS (GuttaFlow Bioseal), and to evaluate the possible influence of a GP cone (Roeko GP point) on the mineralization process. To this end, BG-PDMS disks were aged alone or in the presence of a GP cone in Hank's Balanced Salt Solution (28 d, 37 °C). Dentin remineralization experiments were carried out under the same conditions. Micro-Raman and IR analyses demonstrated that BG-PDMS is bioactive, thanks to the formation of a silica-rich layer with nucleation sites for B-type carbonated apatite deposition. This phase was thicker when BG-PDMS was aged in the presence of GP. The two materials influenced each other because GP, which alone did not show any bioactivity, nucleated a calcium phosphate phase under these conditions. Analogously, dentin remineralization experiments showed that BG-PDMS is able to remineralize dentin, especially in the presence of GP. Under the experimental conditions, GP acted as a templating agent for calcium phosphate deposition.
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Affiliation(s)
- Paola Taddei
- Biochemistry Unit, Department of Biomedical and Neuromotor Sciences, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy;
| | - Michele Di Foggia
- Biochemistry Unit, Department of Biomedical and Neuromotor Sciences, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy;
| | - Fausto Zamparini
- Endodontic Clinical Section, Unit of Odontostomatological Sciences, Department of Biomedical and Neuromotor Sciences, University of Bologna, Via San Vitale 59, 40136 Bologna, Italy; (F.Z.); (C.P.)
| | - Carlo Prati
- Endodontic Clinical Section, Unit of Odontostomatological Sciences, Department of Biomedical and Neuromotor Sciences, University of Bologna, Via San Vitale 59, 40136 Bologna, Italy; (F.Z.); (C.P.)
| | - Maria Giovanna Gandolfi
- Laboratory of Biomaterials and Oral Pathology, Unit of Odontostomatological Sciences, Department of Biomedical and Neuromotor Sciences, University of Bologna, Via San Vitale 59, 40136 Bologna, Italy;
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Karekar A, Schicktanz C, Tariq M, Oßwald K, Reincke K, Cepus V, Langer B, Saalwächter K. Effects of artificial weathering in NR/SBR elastomer blends. Polym Degrad Stab 2023. [DOI: 10.1016/j.polymdegradstab.2023.110267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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6
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Mat Isa N, Hamzah Y, Abdul Halim KA, Osman B, Nasruddin AB, Amir Husin S. Effect of UV-C germicidal irradiation (UVGI) on the structural integrity of N95 and KN95 respirators. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2022; 19:580-589. [PMID: 35819354 DOI: 10.1080/15459624.2022.2100408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
This study focuses on reprocessing a group of filtering facepiece respirators (FFR) using ultraviolet germicidal irradiation (UVGI). The aim is to explore the possibility of disinfecting selected KN95 FFRs, in comparison with the N95 FFRs, and assess their viability for reusage. For this purpose, five models of unused N95 and KN95 FFR models obtained from the hospital were exposed to UV-C light using a customized UVGI chamber. The material integrity of treated FFRs was examined in terms of particle penetration and strap tension. The surface morphology of all models is inspected to determine the visible changes of each FFR upon exposure to 1-100 cycles (1 cycle is equivalent to 1 J/cm2 UV dose). The penetration test results indicate that the physical properties of the KN95 and N95 FFRs remain within permissible limits despite being reprocessed by up to 100 cycles (100 J/cm2). Using a microscope, the physical observations also reveal that no visible damage can be seen even after 100 J/cm2 exposure. Apart from the filter bodies, the tension of each strap was also found to not be significantly affected by UV radiation by at least 10 disinfection cycles (10 J/cm2). This confirms that KN95, as well as N95 FFRs, can be subjected to UV treatment as a means of disinfection.
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Affiliation(s)
- Naurah Mat Isa
- Radiation Processing Technology Division, Malaysian Nuclear Agency, Bangi, Selangor, Malaysia
| | - Yusof Hamzah
- Radiation Processing Technology Division, Malaysian Nuclear Agency, Bangi, Selangor, Malaysia
| | | | - Baderin Osman
- Dust Mask Laboratory, National Institute for Occupational Safety and Health, Bangi, Selangor, Malaysia
| | | | - Suraya Amir Husin
- Medical Development Division, Ministry of Health, Putrajaya, Malaysia
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Surface Chemical and Morphological Analysis of Chitosan/1,3-β-d-Glucan Polysaccharide Films Cross-Linked at 90 °C. Int J Mol Sci 2022; 23:ijms23115953. [PMID: 35682630 PMCID: PMC9180171 DOI: 10.3390/ijms23115953] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 05/21/2022] [Accepted: 05/23/2022] [Indexed: 12/28/2022] Open
Abstract
The cross-linking temperature of polymers may affect the surface characteristics and molecular arrangement, which are responsible for their mechanical and physico-chemical properties. The aim of this research was to determine and explain in detail the mechanism of unit interlinkage of two-component chitosan/1,3-β-d-glucan matrices gelled at 90 °C. This required identifying functional groups interacting with each other and assessing surface topography providing material chemical composition. For this purpose, various spectroscopic and microscopic approaches, such as attenuated total reflection Fourier transform infrared spectroscopy (ATR FT-IR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM), were applied. The results indicate the involvement mainly of the C-C and C-H groups and C=O⋯HN moieties in the process of biomaterial polymerization. Strong chemical interactions and ionocovalent bonds between the N-glucosamine moieties of chitosan and 1,3-β-d-glucan units were demonstrated, which was also reflected in the uniform surface of the sample without segregation. These unique properties, hybrid character and proper cell response may imply the potential application of studied biomaterial as biocompatible scaffolds used in regenerative medicine, especially in bone restoration and/or wound healing.
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8
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Lv M, Fang L, Yu H, Rojruthai P, Sakdapipanich J. Discoloration Mechanisms of Natural Rubber and Its Control. Polymers (Basel) 2022; 14:polym14040764. [PMID: 35215677 PMCID: PMC8875958 DOI: 10.3390/polym14040764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Revised: 02/05/2022] [Accepted: 02/10/2022] [Indexed: 12/10/2022] Open
Abstract
Color is an important indicator for evaluating the quality of natural rubber (NR). Light-colored standard rubbers are widely used in high-grade products and have high economic value. This paper first introduces the history and test standards of the standard light-colored rubber. The origin of color deepening in NR processing, color substances, and its biosynthetic pathway are reviewed. Then, the discoloration mechanism of NR is studied from the perspectives of enzymatic browning (caused by polyphenol oxidase and polyphenols) and non-enzymatic browning (including Maillard reaction and lipid oxidation). Finally, the strategies to control the discoloration of NR will be described.
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Affiliation(s)
- Mingzhe Lv
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Salaya Campus, Mahidol University, Phutthamonthon, Nakhon Pathom 73170, Thailand;
- Institute of Agricultural Product Processing Research, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang 524001, China; (L.F.); (H.Y.)
| | - Lei Fang
- Institute of Agricultural Product Processing Research, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang 524001, China; (L.F.); (H.Y.)
| | - Heping Yu
- Institute of Agricultural Product Processing Research, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang 524001, China; (L.F.); (H.Y.)
| | - Porntip Rojruthai
- Division of Chemical Industrial Process and Environment, Faculty of Science, Energy and Environment, King Mongkut’s University of Technology North Bangkok, Rayong 21120, Thailand;
| | - Jitladda Sakdapipanich
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Salaya Campus, Mahidol University, Phutthamonthon, Nakhon Pathom 73170, Thailand;
- Correspondence:
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10
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Kniazev K, Pavlovetc IM, Zhang S, Kim J, Stevenson RL, Doudrick K, Kuno M. Using Infrared Photothermal Heterodyne Imaging to Characterize Micro- and Nanoplastics in Complex Environmental Matrices. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:15891-15899. [PMID: 34747612 DOI: 10.1021/acs.est.1c05181] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
A key challenge for addressing micro- and nanoplastics (MNPs) in the environment is being able to characterize their chemical properties, morphologies, and quantities in complex matrices. Current techniques, such as Fourier transform infrared spectroscopy, provide these broad characterizations but are unsuitable for studying MNPs in spectrally congested or complex chemical environments. Here, we introduce a new, super-resolution infrared absorption technique to characterize MNPs, called infrared photothermal heterodyne imaging (IR-PHI). IR-PHI has a spatial resolution of ∼300 nm and can determine the chemical identity, morphology, and quantity of MNPs in a single analysis with high sensitivity. Specimens are supported on CaF2 coverslips under ambient conditions from where we (1) quantify MNPs from nylon tea bags after steeping in ultrapure water at 25 and 95 °C, (2) identify MNP chemical or morphological changes after steeping at 95 °C, and (3) chemically identify MNPs in sieved road dust. In all cases, no special sample preparation was required. MNPs released from nylon tea bags at 25 °C were fiber-like and had characteristic IR frequencies corresponding to thermally extruded nylon. At 95 °C, degradation of the nylon chemical structure was observed via the disappearance of amide group IR frequencies, indicating chain scission of the nylon backbone. This degradation was also observed through morphological changes, where MNPs altered shape from fiber-like to quasi-spherical. In road dust, IR-PHI analysis reveals the presence of numerous aggregate and single-particle (<3 μm) MNPs composed of rubber and nylon.
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Affiliation(s)
- Kirill Kniazev
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Ilia M Pavlovetc
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Shuang Zhang
- Department of Electrical Engineering, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Junyeol Kim
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States
- Department of Civil and Environmental Engineering, Wayne State University, Detroit, Michigan 48202, United States
| | - Robert L Stevenson
- Department of Electrical Engineering, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Kyle Doudrick
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Masaru Kuno
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
- Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556, United States
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Njeumen Nkayem DE, Alegria A, Arrese-Igor S, Nkengafac NJ. Rheological and thermal properties of purified raw natural rubber. J RUBBER RES 2021. [DOI: 10.1007/s42464-021-00125-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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12
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13
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Salaeh S, Das A, Wießner S, Stapor M. Vitrimer-like material based on a biorenewable elastomer crosslinked with a dimeric fatty acid. Eur Polym J 2021. [DOI: 10.1016/j.eurpolymj.2021.110452] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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14
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Jung A, Endres MB, Weichold O. Influence of Environmental Factors on the Swelling Capacities of Superabsorbent Polymers Used in Concrete. Polymers (Basel) 2020; 12:polym12102185. [PMID: 32987842 PMCID: PMC7599754 DOI: 10.3390/polym12102185] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 09/20/2020] [Accepted: 09/22/2020] [Indexed: 11/16/2022] Open
Abstract
Superabsorbent polymers (SAP) are of major interest as materials to control the cement hydration process. The swelling behavior of the SAPs significantly influences the performance of the resulting concrete by slowly releasing polymer-bound water in order to maintain a consistent w/c value. A round-robin test conducted by the RILEM Technical Committee 260-RSC showed that the same batch of polymer can lead to large deviations in concrete performance and this was assumed to originate in different storage conditions of the SAP. In this contribution the change in the performance of two SAPs, a crosslinked poly(acrylate) and a crosslinked poly(acrylate-co-acrylamide), was assessed after ageing in standard climate, at 50 °C, and under UV irradiation. During storage in standard climate or 50 °C, ageing led to dehydration of the SAP, and this subsequently led to a higher water uptake during swelling. By contrast, UV irradiation reduced the water uptake, most likely as a result of photo-crosslinking. Dynamic water vapor sorption experiments indicated a strong dependence of the water uptake on both the ambient humidity and the temperature. As a result, cement mixtures containing SAP must be calculated on the dry mass of the SAP rather than the actual weight on site. A standard procedure of how to pack and handle SAP to be used in concrete is also provided.
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Jinyu Sun, Yuan Y, Tian X. Modification of Natural Rubber with Methyl Methacrylate and Diacetone Acrylamide Polymers by O-Carboxymethyl Chitosan. POLYMER SCIENCE SERIES B 2020. [DOI: 10.1134/s156009042003015x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Evaluation of Electron Induced Crosslinking of Masticated Natural Rubber at Different Temperatures. Polymers (Basel) 2019; 11:polym11081279. [PMID: 31370370 PMCID: PMC6723306 DOI: 10.3390/polym11081279] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2019] [Revised: 07/29/2019] [Accepted: 07/30/2019] [Indexed: 11/25/2022] Open
Abstract
In this work, natural rubber (NR) was masticated using an internal mixer to fit the requirements of reactive blending with polylactide and characterized by size exclusion chromatography (SEC), Fourier-transform infrared (FT-IR) spectroscopy and dynamic rheology measurements. Subsequently, the effect of elevated temperatures (25 °C, 80 °C, and 170 °C) on the electron beam (EB) induced crosslinking and degradation of masticated natural rubber (mNR) in a nitrogen atmosphere without adding crosslinking agents has been investigated. The sol gel investigation showed that the gel dose of mNR slightly increased with increasing irradiation temperature, which is also confirmed by the swelling test. The chain scission to crosslinking ratio (Gs/Gx) was found to be less than 1 for irradiated mNR at 25 °C and 80 °C, suggesting a dominating crosslinking behavior of mNR. However, a significant increase of Gs/Gx ratio (~1.12) was observed for mNR irradiated at 170 °C due to the enhanced thermal degradation behavior at high temperature. A remarkably improved elasticity (higher complex viscosity, higher storage modulus, and longer relaxation time) for EB modified mNR was demonstrated by dynamic rheological analysis. Particularly, the samples modified at higher temperatures represented more pronounced elasticity behavior which resulted from the higher number of branches and/or the longer branched chains.
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Santos LP, da Silva DS, Batista BC, Moreira KS, Burgo TA, Galembeck F. Mechanochemical transduction and hygroelectricity in periodically stretched rubber. POLYMER 2019. [DOI: 10.1016/j.polymer.2019.03.028] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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18
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Cp2ZrHCl induced catalytic chain scission of diene-based polymers under mild conditions: Influence of chemical environment around C=C bonds. POLYMER 2019. [DOI: 10.1016/j.polymer.2018.12.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Maldonado-Cubas J, San Martin-Martínez E, Quiroz-Reyes CN, Casañas-Pimentel RG. Cytotoxic effect of Semialarium mexicanum (Miers) Mennega root bark extracts and fractions against breast cancer cells. PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2018; 24:1185-1201. [PMID: 30425433 PMCID: PMC6214441 DOI: 10.1007/s12298-018-0580-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 06/13/2018] [Accepted: 07/17/2018] [Indexed: 05/14/2023]
Abstract
The root bark of Semialarium mexicanum (Miers) Mennega (cancerina) is traditionally used in Mexico to treat cancer. However, there are no studies supporting its use. We evaluated whether S. mexicanum root bark induces cytotoxicity in breast cancer cells to determine if it has potential applications in the treatment of this disease. Extracts of S. mexicanum root bark in petroleum ether, ethanol, and water were obtained by ultrasound-assisted extraction. MTT and WST-1 assays were used to evaluate the cytotoxicity of the extracts toward breast cancer cells (MDA-MB-231 and MCF7), non-tumorigenic breast-derived cells (MCF 10A), and peripheral blood mononuclear cells (PBMCs). For the extract with greatest cytotoxicity, induction of apoptosis and oxidative stress were determined using flow cytometry. The extract was fractionated, and the cytotoxicity of its fractions was evaluated with the four cell types. The fractions were also analyzed by HPLC. Only the petroleum ether extract was cytotoxic for all cell types (MDA-MB-231 > MCF 10A/MCF7 > PBMCs). Cell death occurred by apoptosis, which could be associated with the induction of oxidative stress. Two fractions that were highly cytotoxic for breast cancer cells were obtained from this extract (IC50 ≤ 4.15 µg/mL for the most active fraction at 72 h). The MCF 10A cells were less affected, while PBMCs were not affected after 72 h of treatment. Pristimerin was identified in both fractions and may be partially responsible for the cytotoxic effect. These results suggest that S. mexicanum root bark has a potential application in breast cancer treatment.
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Affiliation(s)
- Juan Maldonado-Cubas
- Instituto Politécnico Nacional, Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, Unidad Legaria, Legaria 694, Irrigación. Miguel Hidalgo, 11500 Ciudad de México, México
| | - Eduardo San Martin-Martínez
- Instituto Politécnico Nacional, Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, Unidad Legaria, Legaria 694, Irrigación. Miguel Hidalgo, 11500 Ciudad de México, México
| | - Cinthya Nathaly Quiroz-Reyes
- Instituto Politécnico Nacional, Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, Unidad Legaria, Legaria 694, Irrigación. Miguel Hidalgo, 11500 Ciudad de México, México
| | - Rocio Guadalupe Casañas-Pimentel
- CONACYT-Instituto Politécnico Nacional, Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, Unidad Legaria, Legaria 694, Irrigación. Miguel Hidalgo, 11500 Ciudad de México, México
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20
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Danna CS, Osorio-Román I, Dognani G, Leopoldo Constantino CJ, Agarwal V, Job AE. Flexible fluorescent films based on quantum dots (QDs) and natural rubber. J Appl Polym Sci 2017. [DOI: 10.1002/app.45459] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Caroline Silva Danna
- Department of Physics, FCT; UNESP Univ Estadual Paulista, Rua Roberto Simonsen 305, Presidente Prudente; Sao Paulo 19060-900 Brazil
- Division of Research and Extension, Faculty of Presidente Prudente-FAPEPE; União Nacional das Inst. de Ensino Superior Privadas-UNIESP, Avenue Presidente Prudente 6093; Presidente Prudente São Paulo 19053-210 Brazil
| | - Igor Osorio-Román
- Department of Physics, FCT; UNESP Univ Estadual Paulista, Rua Roberto Simonsen 305, Presidente Prudente; Sao Paulo 19060-900 Brazil
| | - Guilherme Dognani
- Department of Physics, FCT; UNESP Univ Estadual Paulista, Rua Roberto Simonsen 305, Presidente Prudente; Sao Paulo 19060-900 Brazil
| | - Carlos Jose Leopoldo Constantino
- Department of Physics, FCT; UNESP Univ Estadual Paulista, Rua Roberto Simonsen 305, Presidente Prudente; Sao Paulo 19060-900 Brazil
| | - Vivechana Agarwal
- Faculty of Chemical Science and Engineering, Center for Research in Engineering and Applied Sciences; UAEM, Avenue Universidad 1001; Cuernavaca Morelos 62209 Mexico
| | - Aldo Eloizo Job
- Department of Physics, FCT; UNESP Univ Estadual Paulista, Rua Roberto Simonsen 305, Presidente Prudente; Sao Paulo 19060-900 Brazil
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21
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Sansuk C, Phetrong S, Paoprasert P. Preparation of pH-responsive crosslinked materials from natural rubber and poly(4-vinylpyridine). POLYM INT 2017. [DOI: 10.1002/pi.5316] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Chanon Sansuk
- Department of Chemistry, Faculty of Science and Technology; Thammasat University; Pathumthani Thailand
| | - Sopitcha Phetrong
- Department of Chemistry, Faculty of Science and Technology; Thammasat University; Pathumthani Thailand
| | - Peerasak Paoprasert
- Department of Chemistry, Faculty of Science and Technology; Thammasat University; Pathumthani Thailand
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22
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Li C, Zhu H, Salim NV, Fox BL, Hameed N. Preparation of microporous carbon materials via in-depth sulfonation and stabilization of polyethylene. Polym Degrad Stab 2016. [DOI: 10.1016/j.polymdegradstab.2016.10.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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23
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Characterization of the UV Oxidation of Raw Natural Rubber Thin Film Using Image and FT-IR Analysis. ELASTOMERS AND COMPOSITES 2016. [DOI: 10.7473/ec.2016.51.1.1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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24
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Masa A, Saito R, Saito H, Sakai T, Kaesaman A, Lopattananon N. Phenolic resin-crosslinked natural rubber/clay nanocomposites: Influence of clay loading and interfacial adhesion on strain-induced crystallization behavior. J Appl Polym Sci 2015. [DOI: 10.1002/app.43214] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Abdulhakim Masa
- Department of Rubber Technology and Polymer Science, Faculty of Science and Technology; Prince of Songkla University; Pattani 94000 Thailand
| | - Ryota Saito
- Department of Organic & Polymer Materials Chemistry; Tokyo University of Agriculture and Technology; Koganei-Shi Tokyo 184-8588 Japan
| | - Hiromu Saito
- Department of Organic & Polymer Materials Chemistry; Tokyo University of Agriculture and Technology; Koganei-Shi Tokyo 184-8588 Japan
| | - Tadamoto Sakai
- Shizuoka University, Tokyo Office, Campus Innovation Center Tokyo, 3-3-6 Shibaura; Minato Tokyo 108-0023 Japan
| | - Azizon Kaesaman
- Department of Rubber Technology and Polymer Science, Faculty of Science and Technology; Prince of Songkla University; Pattani 94000 Thailand
| | - Natinee Lopattananon
- Department of Rubber Technology and Polymer Science, Faculty of Science and Technology; Prince of Songkla University; Pattani 94000 Thailand
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25
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Frasca D, Schulze D, Wachtendorf V, Huth C, Schartel B. Multifunctional multilayer graphene/elastomer nanocomposites. Eur Polym J 2015. [DOI: 10.1016/j.eurpolymj.2015.07.050] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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26
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Cowman CD, Padgett E, Tan KW, Hovden R, Gu Y, Andrejevic N, Muller D, Coates GW, Wiesner U. Multicomponent Nanomaterials with Complex Networked Architectures from Orthogonal Degradation and Binary Metal Backfilling in ABC Triblock Terpolymers. J Am Chem Soc 2015; 137:6026-33. [PMID: 25836760 PMCID: PMC4434530 DOI: 10.1021/jacs.5b01915] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
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Selective
degradation of block copolymer templates and backfilling
the open mesopores is an effective strategy for the synthesis of nanostructured
hybrid and inorganic materials. Incorporation of more than one type
of inorganic material in orthogonal ways enables the synthesis of
multicomponent nanomaterials with complex yet well-controlled architectures;
however, developments in this field have been limited by the availability
of appropriate orthogonally degradable block copolymers for use as
templates. We report the synthesis and self-assembly into cocontinuous
network structures of polyisoprene-block-polystyrene-block-poly(propylene carbonate) where the polyisoprene and
poly(propylene carbonate) blocks can be orthogonally removed from
the polymer film. Through sequential block etching and backfilling
the resulting mesopores with different metals, we demonstrate first
steps toward the preparation of three-component polymer–inorganic
hybrid materials with two distinct metal networks. Multiblock copolymers
in which two blocks can be degraded and backfilled independently of
each other, without interference from the other, may be used in a
wide range of applications requiring periodically ordered complex
multicomponent nanoarchitectures.
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Affiliation(s)
- Christina D Cowman
- †Department of Chemistry and Chemical Biology, Cornell University, Baker Laboratory, Ithaca, New York 14853, United States
| | - Elliot Padgett
- ‡Department of Applied and Engineering Physics, Cornell University, Clark Hall, Ithaca, New York 14853, United States
| | - Kwan Wee Tan
- §Department of Materials Science and Engineering, Cornell University, Bard Hall, Ithaca, New York 14853, United States
| | - Robert Hovden
- ‡Department of Applied and Engineering Physics, Cornell University, Clark Hall, Ithaca, New York 14853, United States
| | - Yibei Gu
- §Department of Materials Science and Engineering, Cornell University, Bard Hall, Ithaca, New York 14853, United States
| | - Nina Andrejevic
- ‡Department of Applied and Engineering Physics, Cornell University, Clark Hall, Ithaca, New York 14853, United States
| | - David Muller
- ‡Department of Applied and Engineering Physics, Cornell University, Clark Hall, Ithaca, New York 14853, United States
| | - Geoffrey W Coates
- †Department of Chemistry and Chemical Biology, Cornell University, Baker Laboratory, Ithaca, New York 14853, United States
| | - Ulrich Wiesner
- §Department of Materials Science and Engineering, Cornell University, Bard Hall, Ithaca, New York 14853, United States
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27
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Kookarinrat C, Paoprasert P. Versatile one-pot synthesis of grafted-hydrogenated natural rubber. IRANIAN POLYMER JOURNAL 2015. [DOI: 10.1007/s13726-014-0306-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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28
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Zhang H, Liang G, Gu A, Yuan L. Facile Preparation of Hyperbranched Polysiloxane-Grafted Aramid Fibers with Simultaneously Improved UV Resistance, Surface Activity, and Thermal and Mechanical Properties. Ind Eng Chem Res 2014. [DOI: 10.1021/ie403642m] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Hongrui Zhang
- Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, Department of Materials Science & Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P. R. China
| | - Guozheng Liang
- Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, Department of Materials Science & Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P. R. China
| | - Aijuan Gu
- Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, Department of Materials Science & Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P. R. China
| | - Li Yuan
- Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, Department of Materials Science & Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P. R. China
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29
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30
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Synthesis of natural rubber-based telechelic cis-1,4-polyisoprenes and their use to prepare block copolymers via RAFT polymerization. Eur Polym J 2011. [DOI: 10.1016/j.eurpolymj.2011.01.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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31
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Tanrattanakul V, Chumeka W. Effect of potassium persulfate on graft copolymerization and mechanical properties of cassava starch/natural rubber foams. J Appl Polym Sci 2010. [DOI: 10.1002/app.31514] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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32
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Yamsaengsung W, Sombatsompop N. Use of expanded-EPDM as protecting layer for moderation of photo-degradation in wood/NR composite for roofing applications. J Appl Polym Sci 2010. [DOI: 10.1002/app.31256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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33
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34
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Colom X, Andreu-Mateu F, Cañavate FJ, Mujal R, Carrillo F. Study of the influence of IPPD on thermo-oxidation process of elastomeric hose. J Appl Polym Sci 2009. [DOI: 10.1002/app.30746] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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35
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FT-IR study of gamma-radiation induced degradation of polyvinyl alcohol (PVA) and PVA/humic acids blends. J Radioanal Nucl Chem 2009. [DOI: 10.1007/s10967-009-0321-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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36
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Malmonge JA, Camillo EC, Moreno RMB, Mattoso LHC, McMahan CM. Comparative study on the technological properties of latex and natural rubber fromHancornia speciosaGomes andHevea brasiliensis. J Appl Polym Sci 2009. [DOI: 10.1002/app.29316] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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37
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Tasakorn P, Amatyakul W. Photochemical reduction of molecular weight and number of double bonds in natural rubber film. KOREAN J CHEM ENG 2008. [DOI: 10.1007/s11814-008-0252-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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38
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Baimark Y, Threeprom J, Dumrongcha N, Srisuwan Y, Kotsaeng N. Utilization of Wood Vinegars as Sustainable Coagulating and Antifungal Agents in the Production of Natural Rubber Sheets. ACTA ACUST UNITED AC 2008. [DOI: 10.3923/jest.2008.157.163] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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39
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Gonçalves ES, Ogilby PR. Inside vs "Outside" photooxygenation reactions: singlet-oxygen-mediated surface passivation of polymer films. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:9056-9065. [PMID: 18613710 DOI: 10.1021/la801353n] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Films of poly(acrylonitrile- co-2,3-dimethyl-1,3-butadiene) were exposed to singlet oxygen. The extent of polymer oxygenation was monitored for singlet oxygen generated (1) within the polymer film and (2) at the polymer surface in an aqueous medium. When singlet oxygen is generated within the film, oxygenation of the polymer is pronounced and extensive. When singlet oxygen is generated at the polymer surface, oxygenation reactions are limited to the surface. The data suggest that the initial oxygenation reactions at the film surface passivate the polymer against further reaction with singlet oxygen and, hence, also minimize the progressively detrimental effects of secondary reactions. These results indicate that one should exercise restraint when implicating singlet oxygen as a reactive species in some processes of polymer oxygenation.
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Affiliation(s)
- Elsa Silva Gonçalves
- Center for Oxygen Microscopy and Imaging, Department of Chemistry, University of Aarhus, Arhus, Denmark
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40
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Ruch D, Becker C, Riche A, Etienne S, Bour J. Photooxidation of dyed styrene-butadiene and natural rubbers. POLYMER SCIENCE SERIES A 2008. [DOI: 10.1134/s0965545x08060163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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41
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Guo Q, Liu J, Chen L, Wang K. Nanostructures and nanoporosity in thermoset epoxy blends with an amphiphilic polyisoprene-block-poly(4-vinyl pyridine) reactive diblock copolymer. POLYMER 2008. [DOI: 10.1016/j.polymer.2008.02.033] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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42
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Study of Polymer Material Aging by Laser Mass Spectrometry, UV-Visible Spectroscopy, and Environmental Scanning Electron Microscopy. ACTA ACUST UNITED AC 2007. [DOI: 10.1155/2007/95753] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Dyed natural rubber (NR) and styrene butadiene rubber (SBR), designed for outdoor applications, were exposed to an accelerated artificial aging in xenon light. The aging results in the deterioration of the exposed surface material properties. The ability of dyed polymers to withstand prolonged sunlight exposure without fading or undergoing any physical deterioration is largely determined not only by the photochemical characteristics of the absorbing dyestuff itself but also by the polymer structure and fillers. Results obtained by laser mass spectrometry, UV-visible spectroscopy, and environmental scanning electron microscopy indicate that dyed filled NR and SBR samples behave differently during the photo-oxidation. The fading of the dyed polymers was found to be promoted in the NR sample. This can be correlated with LDI-FTICRMS results, which show the absence of [M-H]− orange pigment pseudomolecular ion and also its fragment ions after aging. This is confirmed by both EDX and UV/Vis spectroscopy. EDX analysis indicates a concentration of chlorine atoms, which can be considered as a marker of orange pigment or its degradation products, only at the surface of SBR flooring after aging. Reactivity of radicals formed during flooring aging has been studied and seems to greatly affect the behavior of such organic pigments.
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43
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Saron C, Zulli F, Giordano M, Felisberti MI. Influence of copper-phthalocyanine on the photodegradation of polycarbonate. Polym Degrad Stab 2006. [DOI: 10.1016/j.polymdegradstab.2006.06.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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44
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Ultraviolet-Enduring Performance of Flexible Pentacene TFTs with SnO[sub 2] Encapsulation Films. ACTA ACUST UNITED AC 2006. [DOI: 10.1149/1.2200069] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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