Segmented block copolymers of polyisobutylene (PIB) and poly(butylene terephthalate) (PBT) were made by condensation polymerization of ~,og-di-anhydride telechelic PIB, with 1,4-butanediol and dimethyl terephthalate. The inherent viscosity of the polymers was between 0.35 and 2.0 dl g1. The extractability of the polymers with hexane was studied. The thermal behaviour of these polymers was studi...

In this study, poly carbonate (PC) and poly (ethylene terephthalate) (PET) were reactive melt-blended under two different conditions to produce PC/PET copolymers. For each condition, samples were taken at specified mixing times representative a specific structure of copolymers and each one employed to physically compatibilize a PC/PET blend with a fixed composition. Reactive blending and copoly...

While equilibrium block-copolymer morphologies are dictated by energy-minimization effects, the semi-ordered states observed experimentally often depend on the details of ordering pathways and kinetics. Here, we explore reordering transitions in thin films of block-copolymer cylinder-forming polystyrene-block-poly(methyl methacrylate). We observe several transient states as films order towards ...

Directed self-assembly of block copolymers has been used for fabricating various nanoscale patterns, ranging from periodic lines to simple bends. However, assemblies of dense bends, junctions and line segments in a single pattern have not been achieved by using sparse templates, because no systematic template design methods for achieving such complex patterns existed. To direct a complex patter...