Sibley School of Mechanical and Aerospace Engineering, Cornell University, NY14850, USA.
Soft Matter. 2017 Apr 12;13(15):2808-2816. doi: 10.1039/c7sm00360a.
Single chain polymer nanoparticles (SCPNs) are formed from intrachain cross-linking of a single polymer chain, making SCPN distinct from other polymer nanoparticles for which the shape is predefined before polymerization. The degree of cross-linking in large part determines the internal architecture of the SCPNs and therefore their mechanical and thermomechanical properties. Here, we use molecular dynamics (MD) simulations to study thermomechanical behavior of individual SCPNs with different underlying structures by varying the ratio of cross-linking and the degree of polymerization. We characterize the particles in terms of shape, structure, glass transition temperature, mobility, and stress response to compressive loading. The results indicate that the constituent monomers of SCPNs become less mobile as the degree of cross-linking is increased corresponding to lower diffusivity and higher stress at a given temperature.
单链聚合物纳米粒子（SCPNs）是由单链聚合物的链内交联形成的，这使得 SCPN 有别于其他聚合物纳米粒子，后者的形状是在聚合前预先确定的。交联度在很大程度上决定了 SCPN 的内部结构，因此也决定了它们的力学和热机械性能。在这里，我们使用分子动力学（MD）模拟来研究不同基础结构的单个 SCPN 的热机械行为，方法是改变交联比和聚合度。我们根据形状、结构、玻璃化转变温度、迁移率以及对压缩载荷的应力响应来描述粒子。结果表明，随着交联度的增加，SCPN 的组成单体的流动性降低，相应地在给定温度下扩散率降低，应力升高。
