检索结果-南通市图书馆

Characterization of the Microstructure Changes of Polypropylene Induced by pan-milling

在线全文

学校读者我要写书评

暂无评论

引用

Chinese Journal of Structural Chemistry 2002年第1期21卷 7-12页

作者： LU Can-Hui WANG Qi ( The state Key Laboratory of Polymer Materials Engineering, Polymer Research Institute, Sichuan University, Chengdu 610065 ) Polymer Research Institute Sichuan University The State Key Laboratory of Polymer Materials Engineering Chengdu 610065

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.

关键词： polypropylene microstructure change mechanochemistry pan-milling

EFFECT OF pan-milling STRESS ON CRYSTAL STRUCTURES OF HIGH DENSITY POLYETHYLENE

在线全文

学校读者我要写书评

暂无评论

引用

Chinese Journal of Polymer Science 2000年第4期18卷 363-367页

作者： Hua Huang Polymer Research Institute, Sichuan University, Chengdu 610065, China School of chemistry and Chemical Technology,Shanghai Jiao Tong University ,Shanghai 200240,China Sichuan Univ Polymer Res Inst Chengdu 610065 Peoples R China Shanghai Jiao Tong Univ Sch Chem & Chem Technol Shanghai 200240 Peoples R China

A detailed study was performed on the crystal structures of pan-milled high-density polyethylene (HDPE) using differential scanning calorimetry (DSC) and X-ray diffraction. The crystallinity of HDPE first decreased slightly, followed by a gradual increase with increasing milling times. Monoclinic crystals appeared after 4 cycles of milling. With increasing times of milling, the proportion of monoclinic crystals increased significantly while the proportion of orthorhombic crystals decreased gradually. With increasing times of milling, the crystallite size of orthorhombic form decreased greatly, while the size of monoclinic crystallites kept almost constant during milling.

关键词： high-density polyethylene pan-milling crystal structure

Solid-state mechanochemistry advancing two dimensional materials for lithium-ion storage applications:A mini review

在线全文

学校读者我要写书评

暂无评论

引用

Nano Materials Science 2023年第2期5卷 210-227页

作者： Xingang Liu Wenbin Kang Xi Li Li Zeng Yijun Li Qi Wang Chuhong Zhang State Key Laboratory of Polymer Materials Engineering Polymer Research InstituteSichuan UniversityChengdu610065China

The vigorous development of two-dimensional(2D)materials brings about numerous opportunities for lithiumion batteries(LIBs)due to their unique 2D layered structure,large specific surface area,outstanding mechanical and flexibility properties,*** technologies for production of 2D materials include but are not limited to mechanochemical(solid-state/liquid-phase)exfoliation,the solvothermal method and chemical vapor *** this review,strategies leading to the production of 2D materials via solid-state mechanochemistry featuring traditional high energy ball-milling and Sichuan University patented pan-milling are *** mechanism involving exfoliation,edge selective carbon radical generation of the 2D materials is delineated and this is followed by detailed discussion on representative mechanochemical techniques for tailored and improved lithium-ion storage *** the light of the advantages of the solid-state mechanochemical method,there is great promise for the commercialization of 2D materials for the next-generation high performance LIBs.

关键词： Two-dimensional materials Solid-state mechanochemistry Ball-milling pan-milling Lithium-ion batteries