State Key Laboratory for Turbulence and Complex Systems & Center for Applied Physics and Technology, College of Engineering, Peking University, Beijing, 100871, P. R. China.
Soft Matter. 2019 Jan 30;15(5):1005-1016. doi: 10.1039/c8sm02427h.
Photopolymerization is a process strongly dependent on the light field in the resin. This typically results in a non-uniformly crosslinked network where some parts of the network are fully cross-linked while other parts are partially crosslinked. The partially crosslinked part could exhibit a high volume expansion upon swelling and a high volume shrinkage upon desolvation. Through control over the light field in the photopolymer resin, this feature has been used to create solvent responsive shape changing structures as well as 3D/4D printed smart devices, showing promising application potential. In this paper, we develop a finite deformation theory to consider the nonuniform crosslink density of the network and the interaction between different species inside the network. The mechanical properties of the network are correlated with the reaction process and the existence of residual uncrosslinked monomers is included in the partially crosslinked network. The efficiency of the theory is proved by the finite element simulations of two special applications of the partially crosslinked network.
光聚合是一个强烈依赖于树脂中光场的过程。这通常会导致交联网络不均匀，其中网络的某些部分完全交联，而其他部分则部分交联。部分交联部分在溶胀时会表现出高体积膨胀，在去溶剂化时会表现出高体积收缩。通过控制光聚合树脂中的光场，已经利用这一特性来创建对溶剂有响应的形状变化结构以及 3D/4D 打印智能设备，显示出有前景的应用潜力。在本文中，我们开发了一种有限变形理论来考虑网络的非均匀交联密度和网络内部不同物种之间的相互作用。网络的力学性能与反应过程相关联，并且部分交联网络中包含残留的未交联单体。通过对部分交联网络的两个特殊应用的有限元模拟证明了该理论的有效性。
