An abnormal melting behavior of isotactic polypropylene spherulites grown at low temperatures
An abnormal melting behavior of isotactic polypropylene spherulites grown at low temperatures
复制标题
低温生长的等规聚丙烯球晶的异常熔融行为
DOI：
10.1016/j.polymer.2017.01.052
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发表时间：
2017-02
期刊：
影响因子：
4.6
通讯作者：
Yan S
中科院分区：
文献类型：
--
作者：
Zhou Z;Ma L;Zhen W;Sun X;Ren Z;Li H;Yan S
采用偏光显微镜（POM）、差示扫描量热仪（TMDSC）、扫描电子显微镜（SEM）、广角X射线衍射（WAXD）和小角X射线散射（SAXS）研究了等规聚丙烯（iPP）的异常熔融行为。POM结果表明，当加热速率为2 °C min−1时，在135 °C等温结晶的α-iPP球晶的熔融先于在125 °C结晶的α-iPP球晶的熔融，但当加热速率为10、20或50 °C min−1时，情况则相反。同步辐射小角X射线散射（SAXS）原位分析发现，在135 °C下生长的α-iPP球晶的初始片层厚度大于125 °C下生长的球晶，而后者的片层厚度大于前者。经过一系列的实验，片层增厚机制可以描述如下，即，在加热过程中，球晶中的切向片晶在径向片晶上熔化重结晶，得到更厚、更完整的径向片晶。
In this work, an abnormal melting behavior of isotactic polypropylene (iPP) was investigated by polarized optical microscopy (POM), temperature-modulated differential scanning calorimetry (TMDSC), scanning electron microscopy (SEM), wide-angle X-ray diffraction (WAXD) and small-angle X-ray scattering (SAXS). It can be found by POM that the melting of α-iPP spherulites isothermally crystallized at 135 °C could occur prior to that of α-iPP spherulites crystallized at 125 °C when heated by 2 °C min−1, but the case is opposite if the heating rates are 10, 20 or 50 °C min−1. Meanwhile, the occurrence of lamellar thickening could be revealed by in-situ synchrotron SAXS, it can be revealed that the initial lamellar thickness of α-iPP spherulites grown at 135 °C is over that of spherulites grown at 125 °C, whereas the latter exceeds the former by means of lamellar thickening after heating. After a series of experiments, the lamellar thickening mechanism could be described as the following, i.e., the tangential lamellae in the spherulite melt and recrystallize on the radial lamellae during heating process, yielding much thicker radial lamellae with higher perfection.
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影响因子：
4.6
作者：
Y. Tanabe;G. Strobl;E. W. Fischer
通讯作者：
Y. Tanabe;G. Strobl;E. W. Fischer
影响因子：
2.5
作者：
A. Turner Jones;Jean M. Aizlewood;D. R. Beckett
通讯作者：
A. Turner Jones;Jean M. Aizlewood;D. R. Beckett
影响因子：
5.5
作者：
L. Mandelkern;R. Sharma;J. Jackson
通讯作者：
L. Mandelkern;R. Sharma;J. Jackson
影响因子：
5.5
作者：
S. Rastogi;Ab Anne Spoelstra;Jgp Han Goossens;Pj Piet Lemstra
通讯作者：
S. Rastogi;Ab Anne Spoelstra;Jgp Han Goossens;Pj Piet Lemstra
DOI：
10.1002/marc.1982.030031018
发表时间：
1982-10
期刊：
Die Makromolekulare Chemie, Rapid Communications
影响因子：
--
作者：
P. Corradini;R. Napolitano;Leone Oliva;V. Petraccone;B. Pirozzi;G. Guerra
通讯作者：
P. Corradini;R. Napolitano;Leone Oliva;V. Petraccone;B. Pirozzi;G. Guerra