Preparation, Structure, and Properties of an Isotactic Polypropylene Film with Ultrahigh Content, Ordered, and Continuous beta-Transcrystallinity
Preparation, Structure, and Properties of an Isotactic Polypropylene Film with Ultrahigh Content, Ordered, and Continuous beta-Transcrystallinity
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超高含量有序连续β-跨晶等规聚丙烯薄膜的制备、结构及性能
DOI：
10.1021/acs.macromol.9b01163
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发表时间：
2019
期刊：
影响因子：
5.5
通讯作者：
Guo Shaoyun
中科院分区：
文献类型：
--
作者：
Liang Guixue;Yang Shuo;Li Jiang;Guo Shaoyun
聚丙烯（PP）的β-跨结晶度（β-TC）是一种具有重要意义的新型晶体。由于传统方法得到的β-TC含量低、不连续性和随机分布，对这种特殊晶体的研究还不够。因此，其形成机制和增长规律尚不明确，其对业绩的影响仍具有包容性。本研究通过含有β-成核剂的环氧树脂板的二维界面诱导连续有序的β-TC。因此，我们获得了一种由纯β-TC组成的PP薄膜，其体积中没有任何助剂，β晶体含量高达92%。根据二维广角x射线衍射测量，随着观察方向的改变，薄膜的晶体学取向发生了很大的变化，据此提出了β-TC在薄膜内的生长模型。此外，通过原位二维小角x射线散射测量和双轴拉伸试验证明，β-TC薄膜由于其特殊的晶体结构，其力学性能和成孔性能得到了显著改善。
β-Transcrystallinity (β-TC) of polypropylene (PP) is a novel kind of crystal that is of significant importance. Owing to the low content, discontinuity, and random distribution of β-TC obtained by traditional methods, there has not been significant research on this particular crystal. Thus, its formation mechanism and growth law remain unclear and their impact on performance is still inclusive. In this study, continuous and ordered β-TC was induced via the two-dimensional interface of an epoxy resin plate that contained the β-nucleating agent. Therefore, we achieved a PP film composed of pure β-TC without any agents in the bulk and a β-crystal content of up to 92%. According to the two-dimensional wide-angle X-ray diffraction measurements, the crystallography orientation of the film greatly differed as the direction of observation changed, depending on which the growth model of β-TC within the film was proposed. Furthermore, it was proved by the in situ two-dimensional small-angle X-ray scattering measurement and biaxial stretching test that the mechanical properties and pore-forming properties of the β-TC film were significantly improved because of its peculiar crystalline structure.