Malaysian Rubber Producers Research Association

Another interesting innovation is that developed by the Malaysian Rubber Producers Research Association. In this case the coupling agent is first joined to a natural rubber molecule involving an ene molecular reaction. The complex group added contains a silane portion which subsequently couples to filler particles when these are mixed into the rubber. 

Technical data sheets , Malaysian Rubber Producers Research Association, Ttin Abdul Razak Laboratory, Brickendonbury, Herts. SG13 8NL (1995). Data sheets for various blends of natural rubber. 

C. S. L. Baker, Vulcanisation with Urethane Reagents, NR Technical Bulletin, Malaysian Rubber Producers Research Association, Brickendonberry,... 

Development of Natural Rubber-Based Truck Tyre Retreading Compounds," in M. E. Cain and Siti Zubaidah bte Mohd Rashid, eds., Proceedings of a UNIDO-sponsored Workshop, Kuala Eumpur, Malaysia, Malaysian Rubber Producers Research Association, Hertford, U.K, 1992. 

Malaysian Rubber Producers Research Association, Brickendonbury, Hertford, England... 

The author wishes to thank Dr. M. Bristow of Malaysian Rubber Producers Research Association - Brickendonbury, U.K. who kindly supplied various grades of natural rubber. He is grateful to Dr. L.A, Goettler and Mr. J. Sezna from Monsanto Polymer Products Company, Akron, Ohio, for the experimental data on Santoprene thermoplastic rubbers used in this paper. 

MALAYSIAN RUBBER PRODUCERS RESEARCH ASSOCIATION Tun Abdul... 

Tables 9.30-9.35 display a series of model formulations on which further compound optimization can be based. Additional formulations are available in industry publications such as those from the Malaysian Rubber Producer s Research Association (Malaysian Rubber Producers Research Association, 1984 Waddell et al., 1990).

Over the years, much of the research on accelerated-sulfur vulcanization was done by using natural rubber as a model substrate. Natural rubber was the first elastomer and therefore the search for understanding of vulcanization originated with work on natural rubber. Even in recent years most of the work published on the study of vulcanization has been related to natural rubber. This was because of the tradition of doing research on natural rubber and because of the fact that the largest knowledge base to build upon was with respect to natural rubber. It should be mentioned that a large factor in the establishment of the tradition of research on the vulcanization of natural rubber was the British Rubber Producers Research Association or BRPRA (now called the Malaysian Rubber Producers Research Association or MRPRA). Of course, this institution is essentially devoted to natural rubber. 

Early rubber technologists were found among the Aztecs and Mayas of South America well over 2,000 years ago who used rubber for coated fabrics, shoe soles and playballs. An article of Malaysian Rubber Producers Research Association mentions that the Aztec king, Montezuma was paid tribute by the lowland tribes in the form of 16,000 rubber balls, and that ball courts have been excavated in Snaketown in the south-western United States dating back to AD 600-900. 

P. B. Lindley, in Engineering Design with Natural Rubber, The Malaysian Rubber Producers Research Association, Brickendonbury, Hertford, 1992, p. 9. 

ENR prepared from chemical modification of NR latex has recently been commercialized. ENR was claimed to have oil resistance property, low gas permeability and more anti-oxidizing and damping than NR. Up to now, many research works have studied its applications and their blends with other polymers such as in this case, the blend between ENR and neoprene (CR) of which the effect of blending ratio on processability of ENR/CR blend was studied by Chiu et al Mastication of ENR (ENR-50, Malaysian Rubber Producers Research Association), CR (ES-2-16K, Du Pont), vulcanizing agent, accelerator, and other related ingredients was carried out in a pressurized kneader (SYD-5, Star-King Enterprise Co., Taiwan) for 17 min under a rotation rate of 77 rpm. Each sample s composition was listed in Table 18.7. 

In comparison with the developments in new rubbers that have occurred this century, developments concerned with the chemistry of the reactions of the already-formed rubbery polymers have been less immediately spectacular. It has already been pointed out that for about ISO years sulphur has been the dominant vulcanizing agent, almost exclusively used with diene rubbers. It must however be stressed that the efficiency with which the sulphur is used and the quality of the vulcanizates is today vastly superior. In part this is due to systematic semi-empirical studies which led to the development of a wide range of accelerators of vulcanization. It is also in part due to the excellent scientific studies undertaken by many chemists throughout the world but particularly by the Malaysian Rubber Producers Research Association (and its forerunners the Natural Rubber Producers Research Association and the British Rubber Producers Research Association). As a consequence of this work the mechanism of vulcanization and its control, at least in the major diene rubbers, is reasonably well understood. 

In recent years there has been increasing interest, particularly by research workers at the Malaysian Rubber Producers Research Association, (MRPRA), in certain reactions that involve the direct reaction between molecules and do not involve active species such as ions and free radicals as intermediates. Among the advantages of such reactions are the fact that catalysts are not involved and that they proceed smoothly, predictably and in a reasonably efficient manner. The reactions of particular interest are those which involve highly substituted ethylenes. These are of particular relevance to polyisoprenes such as natural rubber, which may be considered to be a poly-trisubstituted ethylene, as a means of introducing interesting groups into the polymer structure. 

During the quarter of a century following World War II chemists at the British Rubber Producers Research Association (subsequently renamed the Natural Rubber Producers Research Association and, later, the Malaysian Rubber Producers Research Association) developed this work and using a variety of techniques have largely established the nature of the accelerated sulphur vulcanization of natural rubber. Important contributions have also been made by smaller research teams, for example Scheele and co-workers in Germany, and Craig, Juve, Campbell, Coran and Wise, and others in the United States. These studies have shown, not only that there are a variety of chemical structures present in a vulcanized natural rubber... 

Malaysian Rubber Producers Research Association 1980 Rubber developments 33(3) 62-63... 

Former positions include Manager of Technical Service Laboratory, Ashland Chemical Company. Technical Service Specialist, Malaysian Rubber Bureau, U.S.A. Initiator of testing program for natural-rubber-treaded tires for Canadian Safety Authority and Malaysian Rubber Producers Research Association Laboratories. Author of numerous papers and a book. 

Malaysian Rubber Producers" Research Association, Tun Abdul Razak Laboratory, Brickendonbury, Hertford, UK... 

This chapter deals with materials used by the rubber industry to facilitate the processing of elastomers prior to the vulcanization stage. Much of the work discussed was derived from a number of examinations of specific materials carried out in the laboratories of the Malaysian Rubber Producers Research Association (MRPRA). There is a dearth of such information in a published form thus it is felt that a detailed discussion of the work undertaken would be beneficially published in a laboratory-style reporting form. 

The author wishes to thank the Board of the Malaysian Rubber Producers Research Association for permission to publish this chapter, the editor of Natural Rubber Technology, Deutsche Oelfabrik GmbH and Schill Seilacher for information and samples, and Mr P. M. Lewis for constructive criticism. 

D. H. Champ, E. Southern and A. G. Thomas Malaysian Rubber Producers Research Association Welwyn Garden City, England... 

The authors record their gratitude to the Board of the Malaysian Rubber Producers Research Association for permission to quote extensively from their literature. 

The Malaysian Rubber Producers Research Association (MRPRA) in 1985 has developed a method of generating LNR base on a redox reaction on NR in latex phase. The reducing agent... 

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