Structure and Dynamics of Confined Polymer Melts from Attractive Interaction to Repulsive Interaction Between Polymer and Smooth Wall  

作　　者：LI Sijia ZHANG Wanxi YAO Weiguo SHI Tongfei 

机构地区：[1] College of Materials Science and Engineering, Jilin University, Changchun 130022, P.R.China State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry,Chinese Academy of Sciences, Changchun 130022, P.R.China [2] College of Materials Science and Engineering, Jilin University, Changchun 130022, P.R.China [3] State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry,Chinese Academy of Sciences, Changchun 130022, P.R.China

出　　处：《Chemical Research in Chinese Universities》2015年第3期477-483,共7页高等学校化学研究（英文版）

基　　金：the National Natural Science Foundation of China（Nos.51473168, 21234007）, the Science and Technology Development Program of Jilin Province, China（No.20120319） and the Program of the Key Technology Research for the Slush Process 0fAutomotive Interior Product, China（No.2012362）.

摘　　要：We studied the static and dynamic properties of unentangled polymer chains which have a variable strength of interaction with the confining smooth walls by means of the lattice Monte Carlo simulation based on the bond-fluctuation model, that is, investigated the wall-polymer interactions which systematically vary from attraction to repulsion. A critical value of attractive potential（ewe） is found to be -0.6kilT, and only below it can the adsorption layer of monomers be formed near the wall. At the critical point of attraction ewe, attractive interaction counterba- lances the wall-polymer excluded volume effect, which minimizes the confinement effects on both chain dimension and mobility. Influences on both chain dimension and mobility increase with the increasing of either attraction or repulsion imposed by the walls. Despite of the nature and strength of the wall-polymer interaction, with the decrease of film thickness, configurations more parallelly aligned and flattened are adopted by confined chains, and a systematic trend of deceleration is found. Variations of chain dynamics with both film thickness and wall-polymer interaction can be well explained by the corresponding changes in the confinement of the nearest-neighboring particles that surround the chains. Besides, the thickness of the interfacial layer inside polymer films, where chains adopt a flattened ＂pancake＂ shape, is about two times the bulk radius of gyratioia and independent of the wall-polymer interaction.We studied the static and dynamic properties of unentangled polymer chains which have a variable strength of interaction with the confining smooth walls by means of the lattice Monte Carlo simulation based on the bond-fluctuation model, that is, investigated the wall-polymer interactions which systematically vary from attraction to repulsion. A critical value of attractive potential（ewe） is found to be -0.6kilT, and only below it can the adsorption layer of monomers be formed near the wall. At the critical point of attraction ewe, attractive interaction counterba- lances the wall-polymer excluded volume effect, which minimizes the confinement effects on both chain dimension and mobility. Influences on both chain dimension and mobility increase with the increasing of either attraction or repulsion imposed by the walls. Despite of the nature and strength of the wall-polymer interaction, with the decrease of film thickness, configurations more parallelly aligned and flattened are adopted by confined chains, and a systematic trend of deceleration is found. Variations of chain dynamics with both film thickness and wall-polymer interaction can be well explained by the corresponding changes in the confinement of the nearest-neighboring particles that surround the chains. Besides, the thickness of the interfacial layer inside polymer films, where chains adopt a flattened ＂pancake＂ shape, is about two times the bulk radius of gyratioia and independent of the wall-polymer interaction.

关 键 词：Confinement effect Wall-polymer interaction Critical point of attraction Lattice Monte Carlo simulation 

分 类 号：O431.2[机械工程—光学工程] O631.1[理学—光学]