Seo Youngwook P, Seo Yongsok
RIAM, Department of Materials Science and Engineering, College of Engineering, Seoul National University, Kwanakro 1, Kwanakku, Seoul 08826, Korea.
ACS Omega. 2018 Dec 4;3(12):16549-16555. doi: 10.1021/acsomega.8b02355. eCollection 2018 Dec 31.
Tailoring the polymer melt rheology and the chain relaxation dynamics permits easy handling of polymer processing and enables broader range of applications. Novel strategy to control the polymer melt rheology and the chain relaxation dynamics was devised. A simple process for molecular structural change in a polyamide (nylon 6) to easily generate a long-chain branching in a controllable manner without forming a network structure led to unusually large enhancements in the relaxation dynamics. The zero shear viscosity of the polyamide has increased more than 200 folds of linear chains viscosity, whereas the molar mass change was ca. 1.6 times. Storage modulus and the loss modulus at low frequency increased more than 10 and 10 times to those of neat polyamide without forming a network structure. The rheological properties of the polymer (nylon 6) melts can be finely tailored by this simple process to cover a broad range of applications.
调整聚合物熔体流变学和链松弛动力学可以使聚合物加工易于操作，并能实现更广泛的应用。设计了控制聚合物熔体流变学和链松弛动力学的新策略。一种使聚酰胺（尼龙6）分子结构发生变化的简单工艺，能够以可控方式轻松生成长链支化而不形成网络结构，从而使松弛动力学得到异常大幅的增强。聚酰胺的零剪切粘度比线性链粘度增加了200多倍，而摩尔质量变化约为1.6倍。低频下的储能模量和损耗模量比未形成网络结构的纯聚酰胺分别增加了10倍和10倍以上。通过这种简单工艺可以精细调整聚合物（尼龙6）熔体的流变性能，以涵盖广泛的应用。
