Study on crystallization mechanism of polymers via a new microscopic kinetics model
Category of Research Project：NSF project
list of participants ：XU Jun
beginning and ending dates ：Jan 2014-Dec 2017
Though polymer crystallization has been
intensively studied for decades, there are still some important questions remain
open, such as microscopic mechanism of nucleation, existence of mesophase or
not and variation of properties of crystal embryos with size, etc. In this
proposal, we attempt to solve these challenges via the following strategy:
First, a new model for polymer crystallization will be established, based on microscopic
kinetics of attaching and detaching. The key of the model is the
multibody-interaction parameters that correlate the macroscopic properties,
such as energy barrier, surface free energy and lamellar thickness, to the
microscopic parameters on molecular level. Matlab and Monte Carlo methods will
be applied to simulate the evolution of polymer lamellae so as to reveal the
microscopic mechanism of nucleation, lamellar thickening and melting. Second, the
corresponding experiments will be designed to study the variation of lamellar
thickness with temperature, the properties of the mesophase, and the difference
between small molecule and polymer crystallization. The research is expected to
develop a new theory on polymer crystallization and deepen our understanding of
crystallization.