Multiblock copolymers consisting of polyester and polyaliphatic blocks

Multiblock‐(AB)n‐copolymers, consisting of hard segments of poly(butylene terephthalate) (PBT) and soft segments of dimerized fatty acid were synthesized and analysed with DSC and DMTA. The polymers were characterized by their limiting viscosity number and melt flow index. The glass transition temperature (Tg) and melting temperature (Tm) increase with decreasing weight fraction of the dimerized fatty acid and with the increase of the crystalline phase content. It was found that the elasticity (ϵ) depends on the content of dimerized fatty acid in the amorphous phase. Tensile properties were described as a function of the degree of polycondensation Pk (molecular weight).