Physikalisches Institut and Freiburger Materialforschungszentrum, Albert-Ludwigs-Universität, 79104 Freiburg, Germany.
J Chem Phys. 2020 Apr 21;152(15):150901. doi: 10.1063/1.5139621.
Properties of one and the same polymer can vary greatly with the history of a sample, reflecting its memory of past events. I propose that this remarkable changeability of polymer properties can be related to the immense variability of non-equilibrium conformational states, providing polymers with capacities for responding and adapting to changes in environmental conditions and to external stimuli. By decoding the relations between properties and meta-stable conformational states, we may be able to accomplish polymer products with selectable unique properties. In support of this claim, I first present a few typical examples focusing on changes induced by varying drying, freezing, or crystallization procedures, relevant in many industrial processing strategies for polymeric systems. In these examples, deviations from equilibrium conformations are controlled by a preparation parameter and the annealing/aging time and temperature. Subsequently, I briefly discuss the possibilities for a quantitative description of chain conformations deviating from equilibrium, which allow establishing a link between changes on a molecular level and their macroscopic behavior. A comprehensive and systematic investigation of out-of-equilibrium polymer properties will widen the scope of polymer science and enlarge the range of applications of polymers based on their responsiveness and adaptability derived from their memorizing capacities.
同一种聚合物的性质可能会因其样本的历史而有很大的差异，反映出其对过去事件的记忆。我提出，聚合物性质的这种显著可变性可以与非平衡构象状态的巨大可变性联系起来，为聚合物提供了对环境条件变化和外部刺激做出响应和适应的能力。通过解码性质与亚稳构象状态之间的关系，我们或许能够获得具有可选择独特性质的聚合物产品。为了支持这一说法，我首先提出了几个典型的例子，重点介绍了由不同的干燥、冷冻或结晶程序引起的变化，这些变化在许多聚合物系统的工业加工策略中都很重要。在这些例子中，偏离平衡构象的情况由制备参数以及退火/老化时间和温度来控制。随后，我简要讨论了定量描述偏离平衡的链构象的可能性，这使得我们能够在分子水平上的变化与其宏观行为之间建立联系。对非平衡聚合物性质的全面和系统研究将拓宽聚合物科学的范围，并扩大基于响应性和适应性的聚合物的应用范围，这些响应性和适应性源自它们的记忆能力。
