Polyether based segmented copolymers with uniform aramid units

Segmented copolymers with short, glassy or crystalline hard segments and long, amorphous soft segments (multi-block copolymers) are thermoplastic elastomers (TPE’s). The hard segments form physical crosslinks for the amorphous (rubbery) soft segments. As a result, this type of materials combines elastomeric behavior with melt processability. Typical examples are the copolyetheresters based on poly(butylene terephthalate) and poly(tetramethyleneoxide) (PBT-PTMO, TPE-E) and the thermoplastic polyurethanes (TPE-U). The design and synthesis of copolyetheresteramides with uniform crystallizable bisesterdiamides as the hard segment is a new development. Bisesterdiamides of uniform length crystallize over their full length, resulting in fast and nearly complete crystallization. Consequently, the phase separation is good, leading to a polymer with a low glass transition temperature, a high melting temperature and a temperature independent rubbery plateau. The aim of the research described in this thesis is to study the synthesis and structure-property relations of segmented copolyetheresteramides with uniform, crystallizable bisesterdiamides based on p-phenylenediamine, dimethyl terephthalate (TΦT) and poly(tetramethyleneoxide) (PTMO). Compared to the already existing TPE-E’s and TPE-U’s, TΦT containing segmented copolymers might have improved properties such as a higher heat stability, a wider service temperature range, an improved low temperature flexibility and a faster crystallization.