Rubber, deproteinized natural

The third category of natural rubbers are the specialty materials, which include liquid low molecular weight rubber, methyl methacrylate grafted polymers, oil-extended natural rubber, deproteinized natural rubber, epoxidized natural rubber, and superior-processing natural rubber. 

RSS Ribbed Smoked Sheet DPNR Deproteinized Natural Rubber. 

J. Suksaeree, P. Boonme, W. Taweepreda, G.C. Ritthidej, W. Pichayakom, Characterization, in vitro release and permeation studies of nicotine transdermal patches prepared from deproteinized natural rubber latex blends. Chemical Engineering Research and Design, ISSN 0263-8762 90 (7) (July 2012) 906-914. http //dx.doi.0rg/lO.lOl6/j. cherd.2011.11.002. 

Based on infrared evidence, ester groups in natural rubber were initially reported to be due to the presence of lactone functional groups. " Subsequently, C-NMR studies on deproteinized natural rubber showed that the ester groups were due to the presence of fatty acids bonded to the rubber molecule, of which 80% was saturated fatty acids and 20% unsaturated fatty acids. The fatty acids were later identified to be the acyl component of phosphoHpids hnked to the a-terminal end of the rubber molecule. The phospholipids were also postulated to be the branching point of the natural rubber molecule. The effects of these groups on natural rubber s properties have been discussed above. 

The photoreactive nanomatrix structure was formed by graft copolymerization of the inclusion complex of NDMA with p-CD onto deproteinized natural rubber. The content, conversion and residual methacryloyl group of NDMA for the graft copolymerization were 1.81%, 58.5% and 45.3%, respectively, at NDMA feed of 150 g/kg rubber and initiator concentration of 0.033 mol/kg rubber. The TEM observation of the resulting graft copolymer showed that natural rubber particles of about 1.0 pm in diameter were dispersed in a poly(NDMA) matrix of 10 nm in thickness. 

Fukushima, Y, Kawahara, S., and Tanaka, Y. (1998). Synthesis of graft copolymers from highly deproteinized natural rubber. J. Rubb. Res. 1(3), 154-166. 

Watson and coworkers (68,69) studied in details the mechanical reaction of systems of natural rubber plus poly(methyl methacrylate), using a laboratory masticator at 76 rpm, in a nitrogen atmosphere at 15° C. Prior to mastication, the deproteinized crepe rubber was extracted with acetone, imbibed with mdnomer and allowed to homogenize for 16 h, in the absence of light It must be underlined that, with limited mastication and reaction heat dissipation, the actual rubber temperature was much higher the maximum recorded was about 50° C and... 

On the other hand, the low molecular weight fraction (Mn=10,000) of natural rubber, which was obtained by fractionation of Hevea rubber purified by deproteinization of a commercial latex, showed small signals characteristic of the C-l methylene and C-5 methyl carbon atoms in internal trans units at 39.80 ppm and 16.02 ppm, respectively, as shown in Fig. 6. The signals due to the terminal units were not detected at 59.0 ppm and 17.7 ppm,... 

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