الفهرس 
INTRODUCTION AND THEORETICAL BACKGROUNDOnly 14 pages are availabe for public view
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Abstract
Polymers are compounds whose molecules are composed of large numbers of atomic groups joined by chemical bonds into long chains. According to composition, polymers may be classified as organic, inorganic or organo-metallic polymers. The number of repeated units in the polymeric chain is called the degree of polymerization. Polymers with a high degree of polymerization are called high polymers while those with a low degree of polymerization are known as oligo-polymers. Rubber is an important class of high polymers: predominantly organic, consisting of long chain molecules made up of repeating units usually on a backbone of a carbon atoms. These high molecular weight polymers have a lower temperature limit to their rubbery state at the so called Natural rubber coming from latex is mostly polymerized isoperene with a small percentage of impurities in it. There are limitations on the properties of cis and trans double bonds resulting from methods of polymerizing natural latex. Latex is obtained from the tree by cutting the latex vessels in the bark by a well controlled operation called ”tapping”The latex vessels are living cells which convert plant food materials into rubber hydro-carbon dispersed as a liquid latex.[1 glass transition temperature, Tg.