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一前言 1953年,Natta首次合成了聚丙烯,1956年,他又提出了聚丙烯大分子链具有等规排列的结构模型,并表征了属于单斜晶系的α—晶形。由于这种结构的大分子链容易结晶,随着结晶条件的不同,往往生成各种结晶形态。J.A. Gailey和A.TurnerJoueo等描述了属于六角晶系的另一种晶形,即β-晶形,以及属于三斜晶系的γ-晶形。等规聚丙烯除了上述这些结晶形态外,尚有δ-晶形和正在逐步弄清其结构的所谓准晶。由于结晶形态多,在不同结晶条件下,能够生成各种类型的球晶。因此,研究等规聚丙烯的晶体形态及与其生成条件的关系的工作是很多的。1959年,F.J.Padden,H.D.Keith详细地研究过等规聚
A preface In 1953, Natta first synthesized polypropylene, in 1956, he proposed polypropylene macromolecular chains with isotactic structural model, and characterized the monoclinic α-crystal form. Due to the easy crystallization of the macromolecular chains of this structure, various crystalline forms are often formed as the crystallization conditions are different. J.A. Gailey and A. TurnerJoueo et al. Describe another crystal form belonging to the hexagonal system, namely the β-form and the γ-form belonging to the triclinic system. In addition to the above-mentioned crystalline forms, isotactic polypropylene has a δ-form and a so-called quasicrystal which is gradually recognizing its structure. Due to the large number of crystalline forms, various types of spherulites can be formed under different crystallization conditions. Therefore, the study of isotactic polypropylene crystal morphology and its relationship with the formation of a lot of work. In 1959, F. J. Padden, H. D. Keith studied isotactic polythene in detail