Entangled chains

The entanglement molecular weight Me of SAN copolymers at melt temperatures falls from about 18 [30,34] to 5.0kg/mol [34] as wAn rises from 0.0 

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How do highly interpenetrated random coil chains disentangle to cause fracture Disentanglement is considered to occur as shown in Fig. 14, where we depict the response of an entangled chain to a constant (step function) draw ratio X as follows ... 

A wide variety of polymeric materials exhibit self-similar relaxation behavior with positive or negative relaxation exponents. Positive exponents are only found with highly entangled chains if the chains are linear, flexible, and of uniform length [61] the power law spectrum here describes the relaxation behavior in the entanglement and flow region. 

Rouse normal mode Dynamic response matrix Longitudinal susceptibility Number of entanglements/chain... 

Polymer network with junction points or zones formed by physically entangled chains. 

A comparison of Eqs. 10.55 and 10.59 shows that the diffusivity of an isolated chain due to Brownian motion falls off more slowly with increasing chain size than the diffusivity of an entangled chain diffusing by the reptation mechanism. 

Fig. 6 Micromechanical model of a section of a semi-crystalline polymer with lamellae oriented perpendicular to the principal stress direction showing the long period L and the thicknesses of crystalline (Lc) and amorphous layers (La) the latter are composed of loose segments, entangled chains and more or less extended tie molecules. Large forces can be transferred at those points (o) where highly extended tie molecules (eTM) enter crystalline lamellae...

For high entangled chains, two expressions have been proposed, that of Kramer and Berger [20] ... 

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