We present a phenomenological replica-field theory for symmetric AB copolymer systems with the A.block near its glass transition point. Using a variational principle based on the second Legendre transformation we prove that the interaction between composition fluctuations, due to the loss mobility of the A monomers, results in the elimination of microphase separation. Instead of a microphase se...

Melts of diblock copolymer / homopolymer blends exhibit multiscale phase separation: (i) macrophase separation into homopolymerand copolymer-rich macrodomains followed by (ii) microphase separation into Aand B-rich microdomains within the copolymer-rich macrodomains (cf. [16, 17, 26]). Following our previous derivation in [6], we derive a density functional theory for blends. This theory has be...

Microphase separation in polymeric systems provides a bottom-up strategy to fabricate nanostructures. Polymers that are reported undergo microphase usually include block copolymers or polyelectrolytes. Neutral homopolymers, which comparatively easy synthesize, thought be incapable of separation. Here, using minimal model accounts for ion solvation, we show is possible neutral homopolymer blends...

We consider a microscopic model of a polymer blend that is prone to phase separation. Permanent cross-links are introduced between randomly chosen pairs of monomers, drawn from the Deam-Edwards distribution. Thereby, not only density but also concentration fluctuations of the melt are quenched-in in the gel state, which emerge upon sufficient cross-linking. We derive a Landau expansion in terms...

A series of polyesterurethanes with differing block length and constant composition have been synthesized for rheological studies. Hard segments based on isophorone diisocyanate and 1,4butanediol and soft segments based on polycaprolactone to ensure high thermal stability and to prevent high melting point crystallinity enabled long-duration rheological characterization at high temperatures. DSC...

Small-angle neutron scattering experiments by interpenetrating networks of poly(carbonate-urethane) and polyvinyl pyridine reveal that there is some degree of microphase separation at all compositions, possibly, in some compositions, into a bicontinuous phase. The domain size is some undred angstroms in the samples with only one glass transition