Shear flow is important to understand the relationship between processing and properties of polymer products. In this work, the influences of shearing and high-molecular-weight polybutene-1 (HMwPB) on the evolution of oriented crystal's morphologies of isotactic polybutene-1 (PB) were investigated by shearing at a temperature slightly above the nominal melting temperature under different shear rate and shear duration. The shear thickening presented in primary normal stress revealed the presence of a gel-like network of shish-precursors, in which a birefringence region was observed in polarized optical microscopy (POM) images after crystallization in both PB and PB/HMwPB blend. Those shish-precursors enhanced the crystallization temperature and directly influenced the crystal structures of PB form II, and these crystal structures could be preserved from the form Ⅱ to form Ⅰ. The rheological, one-dimensional scattering, and DSC data reach a plateau with the shear duration, indicating that all the PB chains achieve their ultimate oriented state. The addition of a small amount of HMwPB caused the earlier formation of shish-precursors, the higher crystallization temperature of PB form Ⅱ, thicker lamellae, higher melting temperature, and degree of orientation of PB form Ⅰ.

剪切流对于理解聚合物产品的加工和性能之间的关系很重要。在这项工作中，剪切和高分子量聚丁烯-1 (HMwPB) 对等规聚丁烯-1 (PB) 取向晶体形态演变的影响通过在略高于标称熔化温度的温度下进行剪切研究。剪切速率和剪切持续时间。初级法向应力中出现的剪切增稠表明存在一种凝胶状的前驱体网络，其中在 PB 和 PB/HMwPB 混合物中结晶后，在偏振光学显微镜 (POM) 图像中观察到双折射区域。这些shish前体提高了结晶温度并直接影响了PB晶型II的晶体结构，并且这些晶体结构可以从晶型Ⅱ到晶型Ⅰ保持不变。流变、一维散射和 DSC 数据随着剪切持续时间达到一个平台，表明所有的 PB 链都达到了它们的最终取向状态。少量HMwPB的加入使前驱体形成较早，PB晶型Ⅱ的结晶温度较高，片层较厚，熔融温度较高，PB晶型Ⅰ的取向度也较高。