Dimer fatty acid-modified poly[ester-b-ether]s: Synthesis and properties

Thermoplastic elastomers of the poly[ester-b-ether] copolymer type (PEE) co mprising a hard block of poly(butylene terephthalate) (PBT) and oligoether soft segments, differing in the molecular weight of the oligoether [alpha,o mega-dihydroxy poly(oxytetramethylene) (PTMO); M-n = 650, 1000, and 2900 g/ mol] were synthesized and analyzed. Synthesized PEEs were modified by a dim er fatty acid (DFA, M-n = 570 g/mol) as a component of the soft segments. E ach copolymer (consisting of one hard-segment component and two components of the soft segments) was obtained in a two-stage process involving transes terification and polycondensation in the melt. Elastomer series were prepar ed with a constant PET mass ratio of 50; the content of PTMO and DFA segmen ts was changed. Differential scanning colorimetry results showed a single g lass transition temperature for the mixed PTMO-DFA soft phase, which indica tes that ether and aliphatic units are able to create a homogenous amorphou s phase.