Stability of sectored morphologies of polymer lamellae
Stability of sectored morphologies of polymer lamellae
复制标题
聚合物片层扇形形态的稳定性
DOI：
10.1103/physreve.108.054501
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发表时间：
2023
影响因子：
2.4
通讯作者：
Muthukumar, Murugappan
中科院分区：
文献类型：
--
作者：
Saichand, C.;Hatwalne, Yashodhan;Muthukumar, Murugappan
当相互渗透和纠缠的长柔性聚合物链的溶液冷却到足够低的温度时，这些链结晶成纳米级厚度和微观横向尺寸的薄片。根据溶剂的性质和生长条件的不同，片层表现出具有不同生长动力学和熔化温度的几个部分。值得注意的是，这些薄片可以自发地形成帐篷状形态。实验充分记录的片层扇形和帐篷形成的现象学迄今为止还没有对它们的起源有一个基本的理解。我们提出了一个理论模型来解释这一长期存在的挑战，并从弹性常数和界面张力方面推导出聚合物片的平面、扇形和帐篷形态相对稳定的条件。虽然目前的模型提供了扇形帐篷状形态以及扇形平面形态自发形成的起源的解释，与平面未扇形形态相比，基于聚合物片层的材料特性对形态转变进行了预测。
When a solution of interpenetrating and entangled long flexible polymer chains is cooled to low enough temperatures, the chains crystallize into thin lamellae of nanoscopic thickness and microscopic lateral dimensions. Depending on the nature of the solvent and growth conditions, the lamellae exhibit several sectors that have differing growth kinetics and melting temperatures. Remarkably, these lamellae can spontaneously form tentlike morphology. The experimentally well-documented phenomenology of lamellar sectorization and tent formation has so far eluded a fundamental understanding of their origins. We present a theoretical model to explain this longstanding challenge and derive conditions for the relative stabilities of planar, sectored, and tent morphologies for polymer lamellae in terms of their elastic constants and interfacial tensions. While the present model offers an explanation of the origin of the spontaneous formation of sectored tentlike morphology as well as sectored planar morphology, in contrast to planar unsectored morphology, predictions are made for morphology transformations based on the materials properties of the polymeric lamellae.