Friction between Strongly Compressed Polymer Brushes  

作　　者：Qi Liao 

机构地区：[1]Institute of Chemistry,Chinese Academy of Sciences,Bejing 100190,China

出　　处：《Chinese Journal of Polymer Science》2024年第9期1368-1374,I0008,共8页高分子科学（英文版）

基　　金：supported by the National Natural Science Foundation of China (Nos. 21574139 and 21973103)

摘　　要：We present the results of molecular dynamics simulations of steady shear between a pair of neutral polymer brushes,as well as a pair of charged polymer brushes in the strongly compressed regime.The results of the molecular dynamic simulations of neutral and polyelectrolyte brushes in implicit solvent including normal forces,shear forces,viscosities and friction coefficients as a function of separation between brushes,are presented in the study.The comparison of the simulation results of neutral and charged brushes shows that the charged brushes is in the quasi-neutral regime,and the dependence of viscosity on the separation distance show the similar power law of neutral brushes.Our simulation results confirm that the implicit solvent simulations of polyelectrolyte brushes that ignore hydrodynamics interaction are in agreement with the scaling predictions qualitatively because of screening of hydrodynamic interaction and long-range electrostatic interactions on the correlation length scale.Both of neutral and charged brushes show the lubrication properties that the friction coefficient decreases with the separation decreases at enough large loads.However,a maximum of friction coefficients is observed for polyelectrolyte brushes,which is in contrast to the neutral brushes with monotonical dependence.

关 键 词：Polymer brush Frictions coefficient POLYELECTROLYTE LUBRICATION 

分 类 号：O631.2[理学—高分子化学]