Institute of Physics, University of Silesia in Katowice, ul. 75 Pulku Piechoty 1, 41-500 Chorzow, Poland.
Silesian Center of Education and Interdisciplinary Research, University of Silesia in Katowice, ul. 75 Pulku Piechoty 1A, 41-500 Chorzow, Poland.
Nano Lett. 2020 Aug 12;20(8):5714-5719. doi: 10.1021/acs.nanolett.0c01116. Epub 2020 Jun 30.
Herein we show that the nanostructured interface obtained via modulation of the pore size has a strong impact on the segmental and chain dynamics of two poly(propylene glycol) (PPG) derivatives with various molecular weights ( = 4000 g/mol and = 2000 g/mol). In fact, a significant acceleration of the dynamics was observed for PPG infiltrated into ordinary alumina templates ( = 36 nm), while bulklike behavior was found for samples incorporated into membranes of modulated diameter (19 nm < < 28 nm). We demostrated that the modulation-induced roughness reduces surface interactions of polymer chains near the interface with respect to the ones adsorbed to the ordinary nanochannels. Interestingly, this effect is noted despite the enhanced wettability of PPG in the latter system. Consequently, as a result of weaker H-bonding surface interactions, the conformation of segments seems to locally mimic the bulk arrangement, leading to bulklike dynamics, highlighting the crucial impact of the interface on the overall behavior of confined materials.
本文表明，通过调节孔径获得的纳米结构化界面强烈影响两种具有不同分子量的聚（丙二醇）（PPG）衍生物（= 4000 g/mol 和 = 2000 g/mol）的链段和链动力学。事实上，在 PPG 渗透到普通氧化铝模板中时（= 36 nm），观察到动力学的显著加速，而在掺入调制直径的膜中的样品中发现了类似块状的行为（19 nm < < 28 nm）。我们证明了调制诱导的粗糙度降低了界面附近聚合物链的表面相互作用，与吸附在普通纳米通道上的相互作用相比。有趣的是，尽管在后一种体系中 PPG 的润湿性增强，但仍注意到了这种效应。因此，由于表面氢键相互作用较弱，链段的构象似乎在局部模拟整体排列，导致类似块状的动力学，突出了界面对受限材料整体行为的关键影响。
