Molecular Structure Effects on Melt Viscosity

Since the chemical composition of a polymer defines its flow behavior, we tvill now explore the effects of molecular architecture, such as chain length, the presence of branching, and polarity on these properties. 

Although it is generally true that, as a polymer s chain length increases, its melt viscosity also increases, there are some nuances to this observation. By increasing the chain length, the number of repeat units increases. This creates more entanglements and raises the viscosity. One 

Figur 6,7 General relationship between viscosity and molecular weight 

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