Differential scanning calorimetry of copolymer of isotactic polypropylene backbone with grafted poly(ethylene‐co‐propylene) branches

Abstract

A series of graft polymers having polypropylene (PP) backbone and poly(ethylene-co-propylene) (EPR) side chains was prepared. PP backbone molecular weight (M n ) was 28 -98 kg/mol, EPR side chain M n was 2.6 -17 kg/mol, and EPR content was 0 -16 wt %. In this work, thermal analysis of the copolymers was performed using differential scanning calorimetry (DSC). Nonisothermal crystallization was performed at different cooling rates. The DSC thermograms revealed multiple melting peaks for slowly cooled samples, most likely the result of the melting of thinner tangential lamellae followed by the melting of thicker radial lamellae. Equilibrium melting temperature (T m 0 ) was determined using the linear Hoffman-Weeks method. Another approach was also used for determining