摘要
采用乳液工艺,对天然橡胶(NR)依次进行环氧化和开环接枝改性,引入多重氢键和悬挂链,结合NR优异的高弹性,制备了具有自修复性能的接枝天然橡胶(GENR)。采用红外光谱仪、核磁共振氢谱仪、光学显微镜、万能拉伸机和动态粘弹谱仪分析了接枝产物的改性程度及改性程度和修复条件对修复效率的影响。结果表明:反应温度50℃,pH=5的反应条件下改性程度可达20.8%(摩尔分数),且几乎没有副反应发生。1.0mm厚的GENR 20.8片材在50℃无任何外力下21min即可基本修复断面。GENR 20.8在室温和50℃下分别修复2h,修复效率分别达到了50.6%和81.5%,显示出温和温度条件下快速、高效的自修复能力。氢键网络、弹性恢复以及悬挂链间的物理缠绕是本体系自修复的主要机制。
The natural rubber(NR)was modified by epoxidation and grafting in order through emulsion process.The introduction of multiple hydrogen bonding and pendent group,combined with excellent high elasticity of NR,the grafted natural rubber(GENR)showed self-healing performance.Infrared spectroscopy(FT-IR)and nuclear magnetic resonance(1 H-NMR)were used to analysis the degree of modification.Optical microscope(OM),universal tensile testing machine and dynamic viscoelastic spectrometer were used to evaluate the effect of degree of modification and self-healing conditions on the self-healing efficiency of GENR 20.8.The results showed that under the reaction conditions of 50℃and pH=5,the modification degree was 20.8 mol%and almost no side reactions occurred.The OM results showed that GENR 20.8 surfaces could self-healed in 21 min basically in the absence of any external force.After the two sections of GENR 20.8 contacted at room temperature and 50℃respectively for 2 h,the self-healing efficiency were up to 50.6%and 81.5%separately,suggesting a rapid and efficient self-healing ability under mild temperature condition.The main self-healing mechanisms for this system were the hydrogen bond network,physical entanglement between pendent groups and elastic nature of NR.
作者
王文远
杨凤
高瑞横
焦健
方庆红
Wang Wenyuan;Yang Feng;Gao Ruiheng;Jiao Jian;Fang Qinghong(School of Materials Science and Engineering,Shenyang University of Chemical Technology,Shenyang 110142;Synthetic Resin Factory,China Petroleum Jilin Petrifaction Company,Jilin 132021)
出处
《化工新型材料》
CAS
CSCD
北大核心
2019年第4期53-57,共5页
New Chemical Materials
基金
"十三五"国家重点研发计划课题(2017YBF0306902)
中国科学院合成橡胶重点实验室开放课题(KLSR201702)
关键词
天然橡胶
环氧化
接枝改性
自修复
乳液法
nature rubber
epoxidation
grafting
self-healing
emulsion method
