Irreversible adsorption of polymer chains from a melt on a substrate surface can be strongly affected by interfacial interactions. In this study, we examined the adsorption of two polymers, poly(tert-butyl methacrylate) (PtBMA) and poly(ethyl methacrylate) (PEMA), on a silica surface at temperatures above their glass transition temperatures. The degree of adsorption γ(t) over time was evaluated with variations of storage heat capacity determined with alternating current chip nanocalorimetry (in-situ measurement of a buried interface). γ(t) revealed two-step profiles for both polymers. At the second stage of adsorption (regime II), the slope of a plot of γ(t) vs. log t increased as adsorption proceeded; this trend has not been reported for other polymers and may be characteristic of the present polymers. The trend observed in regime II suggested that the unadsorbed free chains near the interface became less mobile and were incorporated into the adsorbed layer via interactions with the tails of the chains directly attached to the substrate surface. The increasing slope in regime II was more prominent for PtBMA than for PEMA. In addition, a difference was observed for PtBMA and PEMA in the atomic force microscopy images of the exposed adsorption layer surfaces.

基材表面上熔体中聚合物链的不可逆吸附会受到界面相互作用的强烈影响。在这项研究中，我们研究了聚甲基丙烯酸叔丁酯 (PtBMA) 和聚甲基丙烯酸乙酯 (PEMA)两种聚合物在高于其玻璃化转变温度的温度下在二氧化硅表面上的吸附情况。通过交流芯片纳量热法（掩埋界面的原位测量）确定的储存热容量的变化来评估随时间的吸附程度γ（t ）。 γ ( t ) 显示了两种聚合物的两步曲线。在吸附的第二阶段（方案II），随着吸附的进行，γ ( t ) 与 log t的关系图的斜率增加；尚未报道其他聚合物的这种趋势，并且可能是现有聚合物的特征。在方案 II 中观察到的趋势表明，界面附近未吸附的游离链的移动性降低，并通过与直接附着在基材表面上的链尾部的相互作用而并入吸附层中。与 PEMA 相比，PtBMA 在制度 II 中斜率的增加更为显着。此外，在暴露的吸附层表面的原子力显微镜图像中观察到PtBMA和PEMA的差异。