三元乙丙橡胶/尼龙高性能弹性体结构与性能的研究

通过DSC、DMA、TEM及SEM研究了三元乙丙橡胶 /尼龙 (EPDM /PA)共混物结构与性能 ,按照各级结构形态的特点 ,可大致分为三个层次的结构 :初级结构即氯化聚乙烯 (CPE)锚入或镶嵌在PA中形成分散相颗粒中的结构 ;中级结构指分散颗粒在基体中的采取的微纤状形态 ;高级结构是外力作用下共混物形成的由一定数量微纤组成的可传递应力的聚集体结构 .这种多层次结构决定了共混体系兼具EPDM与PA的优点 ,综合性能优异 .物理机械性能及热氧老化性能比较表明 ,PA改性的EPDM是理想的高性能弹性体

INVESTIGATION ON STRUCTURE AND PROPERTIS OF EPDM/NYLON HIGH-PERFORMANCE ELASTOMER

Based upon the DSC, DMA, TEM and SEM observation, a study was made on the structure and property of ethylene\|propylene diene monomer (EPDM)/ternary\|nylon\|copolymer (nylon6/66/1010=20/10/70)(PA) blending systems with excellent properties.The results show that there are three kinds of structure such as follows:After EPDM,PA and chlorinated polyethylene (CPE) being melt blended in 160℃,disperse particles,composed of PA and CPE would be formed.Because of chemical reaction,CPE anchored or inserted into PA.The junior structure refers to dispersed particle itself.It reduces the polarity of PA and improves the compatibility of PA and EPDM.On the other hand,it makes modulus and crystallinity of PA closer to those of EPDM.Some special treatment changes the shape of dispersed particles into a micro\|fiber (intermadiate structure) that could reinforce the EPDM matrix with smaller amount of PA.Also,it could improve magnificently the tear strength,especially hot tear strength of EPDM.EPDM/PA blend,named as micro\|fiber rubber compound,has much better elongation at break than short\|fiber rubber compound and the reason has been given.Only under the effect of external force,the senior structure,which is composed of aggregation bodies,comes into being.Each aggregation body,which could be proved by analysis of SEM observation of surfaces of fractured specimen,includes certain amount of micro\|fibers.It is these sophisticated structures that make the blending system embrace merits of both EPDM and PA and gain excellent comprehensive properties.Compared with main properties of rubber compound cited in literature,EPDM elastormer reinforced by nylon has satisfactory mechanical properties and excellent heat and oxygen\|resistance properties.