【摘 要】
:
The microstructure changes of polypropylene induced by a complex combination of shearing, friction, compression and stretching actions during pan-milling were r
【机 构】
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The state Key Laboratory of Polymer Materials Engineering
论文部分内容阅读
The microstructure changes of polypropylene induced by a complex combination of shearing, friction, compression and stretching actions during pan-milling were revealed by spectroscopic techniques. X-ray diffraction analysis showed that the structure of polypropylene transferred from crystal into amorphous after undergoing enough milling operation. No transformation between crystal forms was observed. The study of the high-frequency region of the Raman spectrum between 2800 and 3100cm-1 of polypropylene indicated that molecular motion and chain deformation of PP led to amorphization and deterioration of packing regularity during pan-milling. By co-panmilling PP with bis-(2,2,6,6-tetramethyl-4-piperidinyl) sebacate under ambient condition, ESR signals of free radicals formed by mechanochemical scission of main chain were observed, and an increase of ESR intensity with milling was detected.
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