不同微孔结构二氧化硅粉体填充三元乙丙橡胶的力学性能及Mullins效应  

Mechanical Properties and Mullins Effect of Ethylene Propylene Diene Monomer Vulcanizes Reinforced with Silica Powders with Different Micropore Structures

作　　者：郭文君 刘璐[1] 刘付永 余雯雯 贾兰[1] 何宏伟[1] 朱凤博 郑强 Wen-jun Guo;Lu Liu;Fu-yong Liu;Wen-wen Yu;Lan Jia;Hong-wei He;Feng-bo Zhu;Qiang Zheng(College of Materials Science&Engineering,Taiyuan University of Technology,Taiyuan 030024;Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering,Taiyuan 030001;Key Laboratory of Macromolecular Synthesis and Functionalization,Department of Polymer Science and Engineering,Zhejiang University,Hangzhou 310027)

机构地区：[1]太原理工大学材料科学与工程学院,太原030024 [2]山西浙大新材料与化工研究院,太原030001 [3]高分子合成与功能构造教育部重点实验室、浙江大学高分子科学与工程学系,杭州310027

出　　处：《高分子学报》2023年第8期1241-1252,共12页Acta Polymerica Sinica

基　　金：山西浙大新材料与化工研究院项目(项目号2021SXTD011);山西省重点研发计划项目(项目号202102040201011);山西省“1331工程”骨干创新团队建设项目(项目号晋教科[2021]4号)资助。

摘　　要：研究了不同微孔结构,粒径相当的二氧化硅气凝胶(AS)、气相法白炭黑(FS)和球形二氧化硅(SS)填充补强三元乙丙橡胶(EPDM)硫化胶的力学性能和Mullins效应.研究发现,具有3倍多于FS比表面积和孔隙体积的AS补强EPDM效果更好,补强后硫化胶拉伸强度比纯EPDM提高928%,比FS/EPDM高4.3%;AS补强后硫化胶的撕裂强度比纯EPDM提高411%,比FS/EPDM提高65.5%.SS对硫化胶力学性能基本没有提高.AS和FS在补强EPDM方面表现出了类似的机理,两者在EPDM中聚集形成了分形维数相近(1.75~1.80)、具有自相似结构的团簇,通过范德华吸附作用吸附在团簇孔隙和表面的结合橡胶将团簇与EPDM分子链段连接共同构筑起三维物理交联网络,起到高效补强效果;结合胶的含量强烈依赖于填料的比表面积和孔隙体积,并决定了三维物理交联网络的强弱,因此AS在补强EPDM方面表现出了更为出色的效果.Ethylene propylene diene monomer(EPDM)was filled with silica aerogel(AS),spherical silica(SS)and fumed silica(FS),which have different micropore structures and closed particle size.The mechanical properties and Mullins effect of EPDM vulcanizates before and after reinforced were analyzed.It was found that,AS with 3 times more specific surface area and pore volume than FS had a much higher reinforcement efficiency for EPDM.The tensile strength of EPDM vulcanizates reinforced with AS is 928%higher than that of pure EPDM and 4.3%higher than that of FS/EPDM.The tear strength of AS/EPDM is 411%higher than that of pure EPDM and 65.5%higher than that of FS/EPDM.SS did not improve the mechanical properties of vulcanizate.AS and FS have similar reinforcement mechanism in reinforcing EPDM.Above a critical content,Self-similar,rigid clusters formed through a diffusion-controlled cluster-cluster aggregation(CCA)with similar fractal dimension(1.75‒1.80)and EPDM chains are connected by the bound molecular segments absorbed in the pore or on the cluster surface through van der Waals force to form physical cross-linking networks.The amount of bound segments,strongly depends on the specific surface area and pore volume of filler,determines the strength of physical networks and the consequent reinforcement efficiency.Therefore,AS shows a higher efficiency in reinforcing EPDM.

关 键 词：二氧化硅粉体 粒子微孔结构 橡胶补强 力学性能 Mullins效应 

分 类 号：TQ333.4[化学工程—橡胶工业]