IISRP Rubber Producers

Specialty Elastomers. Polychloroprene and polysulfide mbber were the first synthetic specialty elastomers discovered. Since theh invention in the 1930s the total number of classes of synthetic mbbers has grown to almost 30. The foUowing lists standard acronyms by the International Synthetic Rubber Producers (IISRP) and the American Society for Testing and Materials (ASTM) for several specialty elastomers. 

The change reflects a change in the International Institute of Synthetic Rubber Producers (IISRP) reporting base growth rates not available in 1994. 

International Institute of Synthetic Rubber Producers (IISRP)... 

World-wide production and consumption in 1992 ca. 5400000 tN.r. were produced world-wide,3975000 t by the major producing countries Thailand, Indonesia, and Malaysia, exact data are given in Lit.. Information on the production and use of N. r. (as well as synthetic rubbers) is provided by the International Institute of Synthetic Rubber Producers (IISRP) and published regularly in specialist journals. 

International Institute of Synthetic Rubber Producers, Inc., Internet publication, http //www.iisrp.com/WebPolymers/... 

International Institute of Synthetic Rubber Producers Inc - IISRP, 2077 South Gessner Rd, Suite 133, Houston, TX 77063-1123 tel +1-713-783-7511 fax +1-713-783-7253... 

The authors collected the test data shown in Table 9.10. From these data it can be noted that the number-average molecular weight, or Af , of a commercial emulsion SBR such as IISRP 1500 or 1712 is typically 90,000-175,000. The primary molecular weight of a solution-polymerized polymer produced with an anionic lithium catalyst can, in contrast, be increased toward 250,000 without gelation. In addition, emulsion-polymerized SBR contains only about 92% rubber hydrocarbon as a result of the presence of residues from the production process solution polymers tend to be near 100% hydrocarbon. As a consequence, the authors concluded that the number-average molecular weight... 

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