Vargas-Lara Fernando, Douglas Jack F
Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
Gels. 2018 Mar 22;4(2):27. doi: 10.3390/gels4020027.
The formation of gels through the bundling of semi-flexible polymer chains into fiber networks is ubiquitous in diverse manufactured and natural materials, and, accordingly, we perform exploratory molecular dynamics simulations of a coarse-grained model of semi-flexible polymers in a solution with attractive lateral interchain interactions to understand essential features of this type of gel formation. After showing that our model gives rise to fibrous gels resembling real gels of this kind, we investigate how the extent of fiber bundling influences the "melting" temperature, T m , and the emergent rigidification of model bundled fibers having a fixed number of chains, , within them. Based on our preliminary observations, we suggest the fiber size is kinetically selected by a reduced thermodynamic driving force and a slowing of the dynamics within the fibers associated with their progressive rigidification with the inclusion of an increasing number of chains in the bundle.
半柔性聚合物链通过聚集形成纤维网络从而形成凝胶，这在各种人造材料和天然材料中普遍存在。因此，我们对具有横向链间吸引相互作用的溶液中的半柔性聚合物粗粒化模型进行了探索性分子动力学模拟，以了解这类凝胶形成的基本特征。在证明我们的模型能够产生类似于此类真实凝胶的纤维状凝胶后，我们研究了纤维聚集程度如何影响“熔化”温度Tm，以及模型中具有固定链数的聚集纤维的刚性化过程。基于我们的初步观察，我们认为纤维尺寸是由降低的热力学驱动力和随着纤维中链数增加其逐渐刚性化导致的纤维内动力学减慢而在动力学上选择的。
