Chain Flexibility and Connectivity:The Uniqueness of Polymer Crystallization

Theory of polymer crystallization is listed as one of the top ten current challenges in polymer community.Clarifying the uniqueness of polymer crystallization should be the first step to search for the roadmap for targeting this challenge.Chain flexibility and connectivity are two peculiar characteristics of polymers,which differentiate their dynamics and structures from that of small molecules.The uniqueness of polymer crystallization must also stem from these two peculiar characteristics,which,however,has not been attracted significant attention.A local structure order may be essential in assisting the transformation of flexible chain to rigid segment with conformational ordering.The entanglement pressure and entanglement free energy may help to understand how entanglement affect nucleation in polymer network and why the interlamellar amorphous layer always accompany the formation of crystal layer.Some recommendations will be given for future study.