Strain Softening of Styrene-Isoprene-Styrene Copolymers under Large Amplitude Oscillatory Shear for Clarifying Payne Effect in Rubbers and Their Nanocomposites  

作　　者：Xin-Peng Fan Yi-Hu Song Qiang Zheng Wan-Jie Wang 

机构地区：[1]MOE Key Laboratory of Macromolecular Synthesis and Functionalization,Department of Polymer Science and Engineering,Zhejiang University,Hangzhou,310027,China [2]Shanxi-Zheda Institute of New Materials and Chemical Engineering,Taiyuan,030000,China [3]College of Materials Science and Engineering,Henan Key Laboratory of Advanced Nylon Materials and Application,Zhengzhou University,Zhengzhou,450001,China

出　　处：《Chinese Journal of Polymer Science》2023年第1期153-165,共13页高分子科学（英文版）

基　　金：the National Natural Science Foundation of China(Nos.U1908221,51873190 and 51790503);Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering(No.2021SZ-TD002).

摘　　要：To illustrate mechanisms of Payne effect in rubbers and their nanocomposites experiencing large amplitude oscillatory shear(LAOS),comparison studies were performed in styrene-isoprene-styrene(SIS)copolymers and their selectively crosslinked materials at temperatures below and above glass transition temperature of the polystyrene(PS)phase.It was found that under periodic dynamic shear,the strain softening is reversible when the polyisoprene(PI)phase,either crosslinked or not,is restricted by hard PS domains but it shows hysteresis once the PS domains disassociate.The strain softening can happen at the time scale of intrinsic Rouse relaxation of elastically active network strands.Critical stress of strain softening scales with number density of elastically active network strands,a simple relation being verified not only in the selectively crosslinked SIS copolymers but also in PI gum vulcanizates and carbon black filled PI compounds.Payne effect is traditionally used to term strain softening of highly filled rubber vulcanizates under LAOS deformation while evidenced herein is that the Payne effect of highly filled rubber vulcanizates shares the mechanism being common to the strain softening of SIS copolymers.

关 键 词：Large amplitude oscillatory shear SIS Rubber nanocomposites Strain softening 

分 类 号：TQ332[化学工程—橡胶工业]