Behavior of Precision Alkyl-Branched Polyolefins

Copolymerization of ADMET EP monomers with 1,9-decadiene, thereby forming linear EP copolymers with random branch distribution, has also been accomplished (Sworen et al., 2003). In this study it was again found that as the branch content increased, overall crystallinity as well as the melting temperatures and enthalpies decreased. In the cases of the highest amount of branch incorporation the random materials exhibited a broad, ill-defined melting behavior in contrast to the sharp melting endotherm observed for the precise models with similar branch content. This drastic difference in the behavior between precise and random models punctuates the effect of precise branch placement (Sworen et al., 2003 Smith et al, 2000). 

Effect of precise methyl placement on thermal behavior 

Ethylene-butene (EB) copolymers featuring precisely placed ethyl branches were the next logical step in this study moving from two single carbon defects to a single two-carbon defect 

Thermal behavior of precision polyolefins with increasing alkyl branch size 

Effect of alkyl branch size on high and low angle refelctions 

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