Rubber summary

RUBBER AND SYNTHETIC ELASTOMERS Table 18.6 Summary of elastomer properties... 

The large deformability as shown in Figure 21.2, one of the main features of rubber, can be discussed in the category of continuum mechanics, which itself is complete theoretical framework. However, in the textbooks on rubber, we have to explain this feature with molecular theory. This would be the statistical mechanics of network structure where we encounter another serious pitfall and this is what we are concerned with in this chapter the assumption of affine deformation. The assumption is the core idea that appeared both in Gaussian network that treats infinitesimal deformation and in Mooney-Rivlin equation that treats large deformation. The microscopic deformation of a single polymer chain must be proportional to the macroscopic rubber deformation. However, the assumption is merely hypothesis and there is no experimental support. In summary, the theory of rubbery materials is built like a two-storied house of cards, without any experimental evidence on a single polymer chain entropic elasticity and affine deformation. 

H. R. Penton, International Rubber Conference Summaries. Stuttgart, Fed. Reb. of Germany, 55 (1985). 

That s good. I ambled along the long rubber-floored breezeway to the next wing and down the hall to my office. I still had time to read some more of Paul Fiddleman s summary. 

Table 6 Summary of Wastewater Sources from Emulsion Crumb Rubber Production Facilities...

Table 7 Summary of Wastewater Sources from Solution Crumb Rubber Production...

Manufacturing (NAICS 326), Rubber Products (NAICS 3262) totals 35.3 billion, of which Tires (NAICS 32621) makes up 15.4 billion, showing the dominance of the automobile tire market in this sector of the chemical industry. The top polymer production summary in Table 1.16 gives a numerical list of important synthetic elastomers. Styrene-butadiene rubber (SBR) dominates the list at 1.93 billion lb for U.S. production. All other synthetic elastomers are much smaller. While elastomers had a slight increase in production from 1980-1990, only 0.5% annually, SBR was down 2.3% per year. From 1990-2000 it was up 1.0% per year. The fastest growing elastomer is ethylene-propylene, up 5.2% annually for 1990-2000. Table 18.1 gives a breakdown in percent production of synthetic elastomers and consumption of natural rubber in the U.S. 

Dibutyl Magnesium, MgCCt. Ct. CI. CHj mw 138.54 clear, dk-amber liq a 20% soln in toluene ignites on contact with red fuming HNO3 was prepd by pptn of Mg chloride from butyl Mg chloride in ether soln with dioxans. This compd was prepd for evaluation as a fuel, or fuel additive in ram jets rockets Ref I.J. Schaffner P.O. Tawney, US Rubber Co March Summary Rept (1948), p 2 (Contract Nord 10129)... 

Refs 1) Beil-not found 2) I.J. Schaffner 8c P.O. Tawney, US Rubber Co February Summary Rept (Feb 1949), p 2 and Progress Rept No 5, p 31 (Contract NORD 10129)... 

In summary, we will review carbon black classifications and their properties in rubber. The three most important properties are particle size, structure, and surface area. We will discuss only the tread grades. All of the tread grades of carbon black fall within the range of 20 nm. to 40 nm. 

A cohort of 748 white male workers occupationally exposed to benzene for varying time periods between 1940 and 1949 in 2 manufacturing facilities producing rubber hydrochloride (Pliofilm ) has been studied (Infante 1978 Infante et al. 1977). The initial report (Infante et al. 1977) included evaluation of mortality statistics up to 1975, and the follow-up study (Infante 1978) included evaluation up to 1977. A summary of the overall results is presented here. Included for the study were all white males assigned to Pliofilm production who were hourly employees at any time between January 1, 1940 and December 31, 1949. 

In summary, carbon blacks work well as conductive additives for plastics and rubbers for applications other than power transmission, provided that a high-structure black and a suitable set of processing conditions are chosen, and as long as the black colour is acceptable. 

In summary, from our brief look at chain conformations we have figured out a way to describe a collection of random chains and realized that among other things, a qualitative understanding of rubber elasticity immediately follows. Moreover, we hope you see how a pathway to more rigorous and quantitative work opens up. 

United States Rubber, Naugatuck Chemical Division, A Literature Summary on Maleic Hydrazide. 1949-1957, and 1957-1963. 

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