Xing Tao, Ma Jiajun, Xu Wen-Cong, Xu Yangguang
Shock and Vibration of Engineering Materials and Structures Key Laboratory of Sichuan Province, Mianyang 621999, China.
Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province, School of Mechanics and Aerospace Engineering, Southwest Jiaotong University, Chengdu 611756, China.
ACS Polym Au. 2025 Mar 7;5(2):162-173. doi: 10.1021/acspolymersau.4c00096. eCollection 2025 Apr 9.
Polysiloxane is an industrially important polymer, as it serves as the platform for the preparation of silicone materials with excellent thermal stability. Even though the fact that introducing rotaxanes into a polymer network provides a novel way to build new materials with peculiar mechanical properties is well-known, this tactic has rarely been applied to silicones, perhaps due to the lack of efficient synthetic methods. Here, in this work, we report the preparation and characterization of novel rotaxanated silicone elastomers by a simple two-step synthetic method. Starting from commercially available γ-cyclodextrin (CD) and vinyl-terminated polydimethylsiloxane, poly[(dimethylsiloxane)-pseudorotaxa-(γ-cyclodextrin)]s were facilely prepared. These pseudopolyrotaxanes were then used to prepare silicone elastomers of different structures and compositions. Mechanical tests of these elastomers show that they have moderate tensile strength but an excellent extension ratio (∼800% for the sample with the highest extension ratio). γ-CD plays a unique and important role in shaping the network's topological structure and mechanical properties. This role was unveiled by applying various techniques such as solid-state NMR measurements and cyclic tensile tests to the elastomers obtained. Due to the simplicity of the current method, it may be used for large-scale preparation of stretchy silicone rubbers with optimum mechanical properties.
聚硅氧烷是一种具有重要工业价值的聚合物，因为它是制备具有优异热稳定性的有机硅材料的平台。尽管将轮烷引入聚合物网络为构建具有独特机械性能的新材料提供了一种新方法这一事实已广为人知，但这种策略很少应用于有机硅，这可能是由于缺乏有效的合成方法。在此，在这项工作中，我们报告了通过一种简单的两步合成方法制备和表征新型轮烷化有机硅弹性体。从市售的γ-环糊精（CD）和乙烯基封端的聚二甲基硅氧烷开始，轻松制备了聚[（二甲基硅氧烷）-假轮烷-（γ-环糊精）]。然后这些假聚轮烷被用于制备不同结构和组成的有机硅弹性体。这些弹性体的力学测试表明，它们具有中等的拉伸强度，但具有优异的伸长率（伸长率最高的样品约为800%）。γ-CD在塑造网络的拓扑结构和力学性能方面发挥着独特而重要的作用。通过对所得弹性体应用各种技术，如固态核磁共振测量和循环拉伸试验，揭示了这一作用。由于当前方法的简单性，它可用于大规模制备具有最佳力学性能的弹性有机硅橡胶。
