针对聚氨酯材料特性设计了多尺度计算机模拟方案,并研究了不同原料及相同原料但不同官能度对所制备的聚氨酯材料力学性能和玻璃化转变温度的影响.基于原子级别的结构,建立了耦合聚合反应的粗粒化耗散粒子动力学模型来描述组分扩散及交联网络结构的形成过程.并反映射这个粗粒化结构到全原子级别来分析材料的力学性能和热力学性能.这个多尺度研究方案也可推广到研究多个竞争性因素同时主导的复杂体系中.
A multiscale simulation strategy was designed based on the features of polyurethane. With this strategy, we investigated the mechanical properties and glass transition temperatures of polyurethane materials crosslinked by different reactants or with different functionalities of the same reactants. From the atomistic simulation results, a coarse-grained dissipative particle dynamics model combined with the reaction module was constructed. Then, this simulation was used to describe the diffusion of components as well as the crosslinking process and the formation of the network structure. Finally, the reverse-mapping scheme was used for atomistic representation and to analyze the mechanical properties and glass transition temperature of the system. This multiscale simulation strategy can be expanded to other complex systems with competing dynamic influencing factors.