Preparation and Characterization of Natural Rubber/Chitosan Films

Natural rubber/chitosan (NR/CS) films at various NR/CS ratios were prepared here from the mixture of natural rubber latex (NRL) and chitosan solution using a solution casting method. The NRLs with and without sulfur curing agents were used. The NR/CS films were obtained after heating at 50oC for 24 hours. The NR/CS films prepared from the NRL with curing agents were further heated at 120oC for 30 min to acquire the NR networks. From swelling testing, it was found that incorporation of CS into the NR matrix gave the films with higher solvent resistance. The swelling index reduced proportionally with the increased CS loadings. Additionally, the solvent resistance of the NR/CS films was improved more once the NR was cured. In general, for every NR/CS ratio, the tensile strengths of the cured NR/CS films were higher than those of the uncured NR/CS films. After thermal aging, it was found that the tensile strength of the uncured NR/CS films decreased while that of the cured ones increased. Two thermal decomposition peaks were observed. The onset decompostion temperatures at lower and higher temperature were corresponding to the degradation of chitosan and natural rubber, respectively. The initial thermal degradation temperature of CS and NR in the NR/CS films was shifted to the higher temperature than that of the pure CS and NR, respectively.

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Fabrication and Characterization of Epoxidized Natural Rubber-Chitosan Membrane

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.844.205 ◽

2013 ◽

Vol 844 ◽

pp. 205-208 ◽

Cited By ~ 1

Author(s):

Wirach Taweepreda ◽

Anuchit Wichianchom

Keyword(s):

Ionic Conductivity ◽

Natural Rubber ◽

Natural Rubber Latex ◽

Chitosan Solution ◽

Epoxidized Natural Rubber ◽

Ether Linkage ◽

Ft Ir ◽

Lcr Meter ◽

Ft Ir Spectroscopy

The membranes obtained from the mixtures of epoxidized natural rubber latex (ENR) and chitosan solution were prepared and characterized. The chemical structure of the membrane was confirmed by ATR-FT-IR spectroscopy and found the peak at 1315 and 1155 cm-1 indicated ether linkage was formed between epoxide group and chitosan corresponding with an enhancement of their mechanical properties which were observed using dynamic mechanical thermal analysis (DMTA). The dielectric properties and ionic conductivity of membrane were investigated using LCR meter and found that the ionic conductivity was increased with increasing the chitosan content.

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Fabrication and characterization of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) modified with nano-montmorillonite biocomposite

e-Polymers ◽

10.1515/epoly-2021-0006 ◽

2020 ◽

Vol 21 (1) ◽

pp. 038-046

Author(s):

Xu Yan ◽

Wanru Zhou ◽

Xiaojun Ma ◽

Binqing Sun

Keyword(s):

Thermal Stability ◽

Oxygen Permeability ◽

Water Vapor Permeability ◽

Barrier Properties ◽

Nucleating Agent ◽

Vapor Permeability ◽

Casting Method ◽

Increasing Trend ◽

Solution Casting Method

Abstract In this study, a poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) modified with nano-montmorillonite biocomposite (MMT/PHBH) was fabricated by solution-casting method. The results showed that the addition of MMT increased the crystallinity and the number of spherulites, which indicated that MMT was an effective nucleating agent for PHBH. The maximum decomposition peak of the biocomposites moved to a high temperature and residue presented an increasing trend. The biocomposites showed the best thermal stability at 1 wt% MMT. Compared with PHBH, 182.5% and 111.2% improvement in elastic modulus and tensile strength were obtained, respectively. Moreover, the oxygen permeability coefficient and the water vapor permeability of MMT/PHBH biocomposites decreased by 43.9% and 6.9%, respectively. It was also found that the simultaneous enhancements on the crystallizing, thermal stability, mechanical, and barrier properties of biocomposites were mainly caused by the formation of intercalated structure between PHBH and MMT.

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Preparation and Characterization of Epoxidised and Acrylated Styrene/Isoprene/Styrene (SIS) Triblock Block Copolymer Based Nanocomposites

Journal of Nepal Chemical Society ◽

10.3126/jncs.v28i0.8112 ◽

2013 ◽

Vol 28 ◽

pp. 84-88 ◽

Cited By ~ 1

Author(s):

Santosh Khanal ◽

Alina Shakya ◽

Goerg H. Michler ◽

Boulos Youssef ◽

Jean M. Saiter ◽

...

Keyword(s):

Block Copolymer ◽

Chemical Society ◽

Performic Acid ◽

Casting Method ◽

Immiscible Polymers ◽

Transmission Electron ◽

Boehmite Nanoparticles ◽

Solution Casting Method

In this work, a commercially available Styrene-Isoprene-Styrene (SIS)triblock copolymer was modified into epoxidised version (ESIS)using performic acid generated in situ from hydrogen peroxide and formic acid. The epoxidised sample was further acrylated to prepare acrylated version (ASIS). The nanocomposites of each sample (SIS, ESIS and ASIS) were prepared using boehmite nanoparticles as filler by solution casting method. The polymers were characterized by Fourier Transform Infrared (FTIR) spectroscopy and transmission electron microscopy (TEM). TEM investigations revealed that that the epoxidation of the diene block enhanced the dispersion of the nanofiller in the polymer matrix while the segregation of the nanoparticles towards the interface of the immiscible polymers was observed in the acrylated block copolymer based nanocomposite. DOI: http://dx.doi.org/10.3126/jncs.v28i0.8112 Journal of Nepal Chemical Society Vol. 28, 2011 Page: 84-88 Uploaded Date: May 24, 2013

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Thermal and Thermo-Oxidative Degradations of Deproteinized Natural Rubber and Natural Rubber

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.306-307.50 ◽

2011 ◽

Vol 306-307 ◽

pp. 50-57 ◽

Cited By ~ 1

Author(s):

Can Zhong He ◽

Zheng Peng ◽

Jie Ping Zhong ◽

Shuang Quan Liao ◽

Xiao Dong She ◽

...

Keyword(s):

Thermal Stability ◽

Natural Rubber ◽

Oxidative Stability ◽

Natural Rubber Latex ◽

Oxidative Degradation ◽

Decomposition Reaction ◽

Nitrogen Atmosphere ◽

Degradation Temperature ◽

Air Atmosphere ◽

Deproteinized Natural Rubber

Deproteinization of natural rubber was achieved in the latex stage. The structure of deproteinized natural rubber (DPNR) was characterized by fourier transform infrared spectroscopy (FTIR). The thermo degradation of DPNR was studied by thermogravimetry analysis (TG) under air atmosphere and nitrogen atmosphere. The kinetic parameters apparent activation energies (Ea) of the thermal decomposition reaction been calculated from the TG curves using the method described by Broido. And the results were compared with the thermo degradation of natural rubber (NR) under the same conditions. The effect of proteins in natural rubber latex on thermal/ thermo-oxidative stability of NR was discussed. The results show that: the absorptions of the proteins in DPNR at 1546 ㎝-1, compared to NR, become significantly weaker, nearly disappear, which indicates most of proteins has been removed from NR. The thermo degradation of DPNR in nitrogen atmosphere is a one-step reaction. The initial degradation temperature (T0) 、the maximum degradation temperature（Tp） and the final degradation temperature（Tf）as well as the Ea of DPNR are higher than those of NR, which indicates that DPNR represents a better thermal stability than NR under nitrogen atmosphere. Thermo-oxidative degradation of DPNR and NR are two-step reaction. The characteristic temperatures (T0, Tp and Tf) of DPNR are lower than those of NR. The Ea during the First Step of Thermooxidative Degradation of DPNR are also lower than those of NR. These results prove that the thermo-oxidative stability of DPNR is worse than that of NR. Protein is the key role to the thermal stability of natural rubber.

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