茂金属聚乙烯/茂金属乙烯-丙烯共聚物共混微观相结构与力学性能

Microscopic Phase Structure and Mechanical Properties of Metallocene Polyethylene/Metallocene Ethylene-Propylene Elastomer Blends

采用密炼机制备了不同组成的茂金属聚乙烯/茂金属乙烯-丙烯共聚物（mPE/mEP）共混体系,利用在线取样-显微分析的方法研究了不同组成mPE/mEP共混体系的微观相态结构,在研究相态结构的基础上,研究了体系的力学性能。结果表明,mPE/mEP共混物呈现明显的两相结构,当mPE体积含量在50%~60%范围内,共混体系形成双连续相,其他组分含量时,形成＂海-岛＂结构形貌。共混物的拉伸强度与共混体系微观相形态的变化有关,断裂伸长率随着mPE含量的增加由2360%降至550%,拉伸模量随着mPE含量的增加由3.5MPa增至102MPa。

Different metallocene polyethylene/metallocene catalyst ethylene-propylene copolymers（mPE/mEP） blend compositions were prepared in mixer.Online-sampling-microscope was employed to study the microscopic phase structure of different compositions of mPE/mEP blends.Besides the structure and morphology of mPE/mEP blends,the mechanical property was also studied.The results show that the two-phase structure is distinctly observed in mPE/mEP blends,the morphology of blends shows co-continuous phase when mPE contents range from 50% to 60%,the ＂sea-island＂ morphology is observed with the other content of components.The tensile strength of blends relates to the microscopic morphology,the elongation at break reduces from 2360% to 550% with increasing mPE content,the tensile modulus increases from 3.5MPa to 102MPa with increasing mPE content.