Chemical Modification of Natural Rubber in the Latex Stage by Grafting Cardanol, a Waste from the Cashew Industry and a Renewable Resource

Our study is part of the general context of valuing by-products from the wood industry, which consists of the chemical modification of xylan by synthesis of branched copolymers such as xylan-g-PLLA. The used xylan is extracted from chestnut and 4-dimethylaminopyridine (DMAP) is the catalyst. In fact, the synthesis of xylan-graft-poly (L-lactide) copolymer starting from natural and renewable resource products xylan and L-lactide is performed under different conditions. The results of the grafting reaction are unfavorable due to longer time because of depolymerization reactions. Another result is the solubility and insolubility of the copolymers synthesized in water. This first result indicates that there is a change in the properties of xylan. Moreover, the solubility of the xylan-g-PLLA copolymers is different from one study to another. Grafting of PLLA onto xylan was confirmed by Fourier transform infrared (FT-IR) and 1HNMR analyzes. The dynamic mechanical analysis showed that the xylan-g-PLLA plastic materials have interesting thermomechanical properties.

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Chemical modification of natural rubber in latex stage for improved thermal, oil, ozone and mechanical properties

Journal of Polymer Research ◽

10.1007/s10965-020-02246-7 ◽

2020 ◽

Vol 27 (9) ◽

Author(s):

Laksana Saengdee ◽

Pranee Phinyocheep ◽

Philippe Daniel

Keyword(s):

Mechanical Properties ◽

Chemical Modification ◽

Natural Rubber ◽

Thermal Oil

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Composite of short coir fibres and natural rubber: effect of chemical modification, loading and orientation of fibre

Polymer ◽

10.1016/s0032-3861(97)00422-9 ◽

1998 ◽

Vol 39 (6-7) ◽

pp. 1483-1491 ◽

Cited By ~ 207

Author(s):

V.G. Geethamma ◽

K. Thomas Mathew ◽

R. Lakshminarayanan ◽

Sabu Thomas

Keyword(s):

Chemical Modification ◽

Natural Rubber

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Influence of Filler from a Renewable Resource and Silane Coupling Agent on the Properties of Epoxidized Natural Rubber Vulcanizates

Journal of Chemistry ◽

10.1155/2015/796459 ◽

2015 ◽

Vol 2015 ◽

pp. 1-15 ◽

Cited By ~ 20

Author(s):

Wiphawadee Pongdong ◽

Charoen Nakason ◽

Claudia Kummerlöwe ◽

Norbert Vennemann

Keyword(s):

Mechanical Properties ◽

Metal Oxide ◽

Natural Rubber ◽

Elevated Temperatures ◽

Polymer Network ◽

Renewable Resource ◽

Dynamic Mechanical Properties ◽

Epoxidized Natural Rubber ◽

Cure Characteristics ◽

Temperature Scanning

Rice husk ash (RHA) was used as a reinforcing filler in epoxidized natural rubber (ENR) with various loading levels (0, 10, 20, and 30 phr), and silica filled ENR was also studied for comparison. The effects of RHA content on cure characteristics, mechanical properties, dynamic mechanical properties, and thermoelastic behavior of the filled ENR composites were investigated. It was found that the incorporation of RHA significantly affected the cure characteristics and mechanical properties. That is, the incorporation of RHA caused faster curing reactions and increased Young’s modulus and tensile strength relative to the unfilled compound. This might be attributed to the metal oxide impurities in RHA that enhance the crosslinking reactions, thus increasing the crosslink density. Further improvements in the curing behavior and the mechanical properties of the filled composites were achieved byin situsilanization with bis(triethoxysilylpropyl) tetrasulfide (Si69). It was found that the rubber-filler interactions reinforced the composites. This was indicated by the decreased damping characteristic(tan ⁡δ)and the other changes in the mechanical properties. Furthermore, the ENR composites with Si69 had improved filler dispersion. Temperature scanning stress relaxation (TSSR) results suggest that the metal oxide impurities in RHA promote degradation of the polymer network at elevated temperatures.

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Dielectric Studies of Admicelled Natural Rubber with Poly(3-Trimethoxysilylpropyl Methacrylate)

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.844.373 ◽

2013 ◽

Vol 844 ◽

pp. 373-376

Author(s):

Suparat Nooma ◽

Rathanawan Magaraphan

Keyword(s):

Dielectric Constant ◽

Composite Materials ◽

Dielectric Properties ◽

Chemical Modification ◽

Natural Rubber ◽

Microwave Frequency ◽

Dielectric Studies ◽

Frequency Range ◽

Admicellar Polymerization ◽

Methoxy Groups

In this work, 3-trimethoxysilylpropyl methacrylate (MPS) was used as a substrate for coating on natural rubber (NR) particles by admicellar polymerization. The incorporation of MPS monomer, consisting of silicon element and 3 reactive methoxy groups (R-Si(OCH3)), is expected to increase dielectric properties of NR. Under the admicellar polymerization, the R-Si(OCH3) groups can be hydrolyzed and condensed into polysiloxane existed on NR particles. This method aims to prepare composite materials from NR and MPS with various amounts of MPS. The effects of microwave frequency and chemical modification by admicellar polymerization were studied. The dielectric properties of admicelled natural rubber (adNR) with PMPS were investigated at 20 °C in a frequency range extended from MHz to GHz. The results showed that the dielectric constant of adNR increased with PMPS contents. To study the effect of crosslinking on the dielectric properties of adNR, the dielectric spectroscopy measurements were performed on prevulcanized and non-prevulcanized adNR. The investigation showed that the dielectric constant of non-prevulcanized adNR was less than prevulcanized adNR.

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