Speaker：Prof. Yongfeng Men，State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Science

Title: Microscopic mechanism of the mechanical behavior of crystalline polymers

Time：November 26, 2019，14：30 pm

Venue: Lecture Room 324, AISMST (Building #2, KeJiYuan, North Campus)

Faculties and students are warmly welcome.

School of Molecular Science and Engineering

South China Advanced Institute for Soft Matter Science and Technology

November 19, 2019

Abstract:

Most polymer materials are crystalline, and most of them are used as structural materials in the presence of external forces. Therefore, understanding the mechanical deformation mechanism of crystalline polymers is essential for the safe service of polymer products. This talk mainly introduces our modeling of the microstructure of crystalline polymers and their applications in understanding the mechanical behaviors. A typical crystalline polymer material can be regarded as an interpenetrating network structure composed of a crystalline hard skeleton and an entangled amorphous soft network. This model can well explain the evolution of microstructure in the process of tensile deformation of crystalline polymers, including: critical strain behavior, plastic deformation, and cavitation of the system. This talk will discuss in detail the microstructure evolution path of the crystalline polymer material during the tensile deformation process, and describes the microstructural origin that determines the behaviors such as yielding, microfibrillation, and stress whitening.

Brief Biography：

Yongfeng Men, male, born in 1973, graduated from the Physics Department of Southeast University in 1995. He obtained the Master degree in polymer physics from Changchun Institute of Applied Chemistry, Chinese Academy of Sciences in 1998 and a PhD degree in Physics from the University of Freiburg, Germany in 2001. From 2002 to 2005, he worked as a postdoctoral fellow and Physicist in polymer physics research department at BASF in Germany. In 2005, He joined the State Key Laboratory of Polymer Physics and Chemistry at Changchun Institute of Applied Chemistry as a full professor. He is currently the deputy director of the State Key Laboratory of Polymer Physics and Chemistry, focusing on the study of structure and performance of polymer materials. He mainly uses scattering techniques (X-ray, neutrons, etc.) to investigate the polymer crystallization, mechanical relaxation of crystalline polymers and polymer structural deformation and destruction behaviors.