论文标题
具有高密度可逆键的联想聚合物的动力学
Dynamics of Associative Polymers with High Density of Reversible Bonds
论文作者
论文摘要
我们设计和合成未进入的关联聚合物，载有前所未有的高贴纸，每个kuhn片段最多可以形成$ \ sim20k_bt $的强大成对氢键，而无需显微镜分离。可逆键显着降低了聚合物动力学，但几乎不会改变线性粘弹性光谱的形状。此外，关联聚合物的结构放松时间随贴纸的比例而呈指数增加，并表现出对聚合物玻璃透过温度距离的通用但非Arrhenius的依赖性。这些结果在经典的粘屋模型的框架内无法理解，但通过重新归一化的Rouse模型合理化，该模型突出了可逆键对结构放松的意外影响，而不是粘胶光谱的形状对于具有高浓度贴纸的关联聚合物的形状。
We design and synthesize unentangled associative polymers carrying unprecedented high fractions of stickers, up to eight per Kuhn segment, that can form strong pairwise hydrogen bonding of $\sim20k_BT$ without microphase separation. The reversible bonds significantly slow down the polymer dynamics but nearly do not change the shape of linear viscoelastic spectra. Moreover, the structural relaxation time of associative polymers increases exponentially with the fraction of stickers and exhibits a universal yet non-Arrhenius dependence on the distance from polymer glass transition temperature. These results cannot be understood within the framework of the classic sticky-Rouse model but are rationalized by a renormalized Rouse model, which highlights an unexpected influence of reversible bonds on the structural relaxation rather than the shape of viscoelastic spectra for associative polymers with high concentrations of stickers.
