青岛科技大学贺爱华团队报道了，原位熔体预剪切诱导取向前驱体对聚-丁烯/聚丙烯共混物结晶的影响。相关研究成果发表在2024年11月11日出版的《中国高分子科学杂志》。

熔融预剪切诱导聚合物共混物结晶，在工业加工和产品应用中具有重要意义。

该文中，研究人员采用了两种具有商业价值和学术热点的典型PB/PP共混物（50/50、90/10），通过在略高于PP熔融温度的条件下施加剪切，随后进行非等温结晶，来研究熔融预剪切对全同立构聚（1-丁烯）（PB）和聚丙烯（PP）结晶的影响，以模拟实际加工条件。

研究发现，在PB/PP（90/10）共混物中，原位熔融预剪切产生的定向PP前体诱导了PP-FIC（流动诱导结晶）的形成，PP-FIC作为行晶核，显著促进了PB结晶为球晶，具有更高的熔融温度（Tm）、结晶度（Xc）和更厚的片层厚度（dc）。在PB/PP（50/50）共混物中，熔体预剪切产生的PP串晶前体诱导了PP串晶的形成，对PB的晶体生长产生了限制作用，导致截断球晶形成，Tm更高，dc更厚，但Xc更低。

该研究深入探讨了PB/PP共混物在熔体预剪切场下，定向晶体结构形成、晶体性能和相形态的机制，这对其工业加工和高性能产品的制备具有重要的理论和实践意义。

附：英文原文

Title: The Effect of In situ Melt Pre-shear Induced Oriented Precursors on the Crystallization of Poly(1-butene)/Polypropylene Blends

Author: Wen-Kang Wei, Jing-Jing Zhao, Chen-Guang Liu, Dong Wang, Ai-Hua He

Issue&Volume: 2024-11-11

Abstract: Melt pre-shear induced crystallization of polymer blends holds great significance in industrial processing and product application. In this work, two typical PB/PP blends (50/50, 90/10), possessing commercial value and academic hotspot, were employed to investigate the effect of melt pre-shear on the crystallization of isotactic poly(1-butene) (PB) and polypropylene (PP) by applying shearing slightly above the melting temperature of PP with subsequent non-isothermal crystallization to simulate actual processing conditions. It was discovered that in PB/PP (90/10) blend, in situ melt pre-shear generated oriented PP precursors induced the formation of PP-FIC (Flow-induced crystallization) which acted as row crystal nucleus significantly promoting PB crystallization into spherulite with higher melting temperatures (Tm), crystallinity (Xc), and thicker lamellar thickness (dc). While in PB/PP (50/50) blend, the melt pre-shear generated PP-shish precursors induced the formation of PP shish-kebab that exerted a confining effect on the crystal growth of PB, resulting in truncated spherulite formation with higher Tm and thicker dc but lower Xc. This research provides insight into the mechanism underlying oriented crystal structure formation, crystal properties, and phase morphology of PB/PP blends under melt pre-shear fields, which have significant theoretical and practical implications for their industrial processing and preparation of high-performance products.

DOI: 10.1007/s10118-024-3240-3

Source: https://www.cjps.org/en/article/doi/10.1007/s10118-024-3240-3/