Synthesis and properties of polyimides containing polybutadiene blocks

Abstract

Polyimides containing polybutadiene blocks were prepared by copolycondensation of benzophenone‐3,3′,4,4′‐tetracarboxylic dianhydride, diphenylmethane‐4,4′‐diisocyanate and isocyanate‐endcapped polybutadiene LBD‐3000. 13C NMR CP‐MAS and FTIR spectroscopies were used to determine the chemical structure of the copolymers. TGA showed that the thermal stability of the copolymers in inert atmosphere is almost independent of the polybutadiene content in the copolymer (as follows from the temperature of 10% and 20% weight loss). Stress–strain experiments showed that copolymers containing amounts of polybutadiene higher than 59 wt% exhibited elastomeric behaviour. © 1999 Society of Chemical Industry

Segmented Polyimides with Poly(ethylene oxide) Blocks Exhibiting Liquid Crystallinity

“…However, following early work by de Vissier et al on polyimides derived from pyromellitic dianhydride and diamines with poly(ethylene oxide) sequences, there has been continuing interest in polyimides with aliphatic moieties, e.g., in polyimides of structure 1 in which either or both X and Y incorporate aliphatic units and/or various linking groups. Although there have been a few studies of segmented polyimides containing other aliphatic sequences, − the main emphasis has been on those with sequences of methylene or ethylene oxide (EO) units. Thus, Harris and co-workers described polyimides in which X had various structures and Y included −(O−CH 2 −CH 2 −) n −O− sequences ( n = 1 to 3 or 4) with phenylene linking units with different substitution patterns and, in some cases, methyl substituents. − Several of these polymers exhibited multiple endothermic (melting) transitions on heating.…”