Subject molar mass effects

R4 and L-64 are very similar in chemical composition and have only a small difference of about 9% in the total molar mass. Therefore, they constitute a good pair of subjects to compare the effect of chain architecture on phase behavior and association properties. 

As mentioned above, most polymers are characterized by a distribution of molar masses of the individual polymer chains that is, almost every polymer sample is a mixture of polymers with different molar masses, an effect which is referred to as polydispersity. In the past, significant attempts have been made to produce polymers with a narrow molar mass distribution, and to prepare polymers with precisely identical molar masses. This is a consequence of the inherent desire of the synthetic chemist to produce a compound that is as well defined as possible - in just the way that Nature teaches us. Yet, only natural polymers such as DNA are really 100% monodisperse. In the following case study, it should be noted that even the absolute counterpoint to these longlasting attempts can open the way to a successful polymer in a highly competitive market. The subject here is probably the most competitive landscape in polymer chemistry over all, the polyolefins. 

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