Abstract The thermal transitions of confined polymers are important for their applications in nanoscale devices and innovative technologies. However, thermal transitions of ultra-thin polymer assemblies confined in sub-nanometer spaces are unwell understood. In this work, the self-assembly of hyperbranched polyester-polyol polymers (HPP) immobilized on carbon surfaces were investigated. The physicochemical properties and thermal transitions of the polymers under confinement were revealed by cyclic voltammetry, electrochemical impedance spectroscopy and atomic force microscopy. The adsorption of HPP with hydroxyl-terminal groups on the bare carbon surface followed typical porous solid isotherm due to hydrogen-bond forces. The dependence of the HPP nanometer-sized layers against temperature revealed a phase transition at ca. 306 K. This phase transition can be explained in terms of polymer layer reorganization due to the temperature effect on the intermolecular hydrogen-bonding instead of a glass transition. This feature is of particular relevance for further applications of hyperbranched polymers thin films in nanodevices.

中文翻译：

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碳上超支化聚酯-多元醇组件的热转变

摘要 受限聚合物的热转变对其在纳米器件和创新技术中的应用很重要。然而，限制在亚纳米空间中的超薄聚合物组件的热转变尚不清楚。在这项工作中，研究了固定在碳表面上的超支化聚酯-多元醇聚合物 (HPP) 的自组装。通过循环伏安法、电化学阻抗谱和原子力显微镜揭示了限制条件下聚合物的物理化学性质和热转变。由于氢键力，具有羟基末端基团的 HPP 在裸碳表面上的吸附遵循典型的多孔固体等温线。HPP 纳米尺寸层对温度的依赖性揭示了约 306K。由于温度对分子间氢键的影响而不是玻璃化转变，因此可以根据聚合物层重组来解释这种相变。这一特征与超支化聚合物薄膜在纳米器件中的进一步应用特别相关。