Influence of chloroacetate group on physical properties of natural rubber and its interaction with fillers

Abstract

Filler–rubber composites were prepared by mixing chloroacetated natural rubber (CNR) with silica, carbon black (CB), or calcium carbonate using a two‐roll mill. The interactions between the CNR and fillers, including silica, carbon black, and calcium carbonate, were characterized based on glass transition temperature (Tg) and shear storage modulus (G′). The results showed that both the Tg and G′ values of the CNR‐Si composite were found to be higher than those of the CNR–CB and CNR–CaCO3 composites, indicating the existence of the CNR and silica interaction. The outstanding direct interaction between the CNR rubber matrix and silica without using a coupling agent was believed to be due to hydrogen bonds that formed between the hydroxyls of the silanol groups of silica and the carbonyls in the chloroacetate groups of CNR molecules. Moreover, it was also found that silica dispersed and distributed in the CNR matrix much better than in the natural rubber matrix. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43076.

Properties of tire tread compounds based on functionalized styrene butadiene rubber and functionalized natural rubber

“…Results suggest that modification of NR molecules with chloroacetate group noticeably improves the interaction between rubber matrix and filler surface. The increased rubber‐filler interaction could be explained by the strong H‐bond between the hydroxyl group on silica surface and the chloroacetate group on rubber molecules as proposed in Figure (a) …”

“…It was prepared by reacting NR latex with hydrogen peroxide and formic acid to form epoxidized natural rubber latex and finally with chloroacetic acid. Full details of CNR preparation are described elsewhere . NR (STR 5 L) was manufactured by Union Rubber Product Co., Ltd., Thailand.…”

“…Meanwhile, chemical modification of NR molecules has also gained much attention from many researchers. Recently, a novel functionalized NR has successfully been produced by grafting chloroacetate groups into NR molecules, the so‐called chloroacetated natural rubber (CNR), via the sequential reactions of NR latex with performic acid to form epoxidized NR and, finally, with chloroacetic acid . Compared to NR, the CNR has demonstrated superiority in interaction with reactive fillers, particularly silica.…”

Nanofiber films of chloroacetated natural rubber/poly(vinyl alcohol) by electrospinning technique: Silica effects on biodegradation

“…The NRL was purchased from Thai Eastern Rubber Co. Ltd. (Thailand). CNR was synthesized according to a previously described procedure by our group . Briefly, NRL, hydrogen peroxide, and formic acid were mixed together with the mole ratio of 1:0.25:0.25 based on the dry rubber content (DRC).…”

“…Few studies have been conducted on natural rubber latex (NRL) for biomedical application and showed no cytotoxicity of NRL with human fibroblast and osteoblast cells with good cell adhesion and proliferation . Chloroacetated natural rubber (CNR) is a novel promising elastomeric polymer derived directly from chemical modification of NRL through epoxidation reaction followed by the addition of chloroacetic acid . There are several factors such as biocompatibility, flexibility, and antibacterial prominence that make CNR a unique candidate biopolymer.…”