Lan Xiaohong, Boetje Laura, Pelras Théophile, Ye Chongnan, Silvianti Fitrilia, Loos Katja
Macromolecular Chemistry & New Polymeric Materials, Zernike Institute for Advanced Materials, University of Groningen Nijenborgh 4 9747AG Groningen The Netherlands
Polym Chem. 2023 Oct 20;14(44):5014-5020. doi: 10.1039/d3py00883e. eCollection 2023 Nov 14.
Dynamic covalent networks (DCNs) are materials that feature reversible bond formation and breaking, allowing for self-healing and recyclability. To speed up the bond exchange, significant amounts of catalyst are used, which creates safety concerns. To tackle this issue, we report the synthesis of a lipoic acid-based vitrimer-like elastomer (LAVE) by combining (i) ring-opening polymerization (ROP) of lactones, (ii) lipoic acid modification of polylactones, and (iii) UV crosslinking. The melting temperature () of LAVE is below room temperature, which ensures the elastic properties of LAVE at service temperature. By carefully altering the network, it is possible to tune the , as well as the mechanical strength and stretchability of the material. An increase in polylactone chain length in LAVE was found to increase strain at break from 25% to 180% and stress at break from 0.34 to 1.41 MPa. The material showed excellent network stability under cyclic strain loading, with no apparent hysteresis. The introduction of disulfide bonds allows the material to self-heal under UV exposure, extending its shelf life. Overall, this work presents an environmentally friendly approach for producing a sustainable elastomer that has potential for use in applications such as intelligent robots, smart wearable technology, and human-machine interfaces.
动态共价网络(DCNs)是一类具有可逆键形成和断裂特性的材料,具备自我修复和可回收性。为了加速键交换,需要使用大量催化剂,这引发了安全问题。为解决这一问题,我们报道了一种基于硫辛酸的类维特莫尔弹性体(LAVE)的合成方法,该方法通过以下步骤实现:(i)内酯的开环聚合(ROP),(ii)聚内酯的硫辛酸改性,以及(iii)紫外线交联。LAVE的熔点低于室温,这确保了其在使用温度下的弹性性能。通过仔细调整网络结构,可以调节材料的熔点,以及其机械强度和拉伸性。研究发现,LAVE中聚内酯链长度的增加会使断裂应变从25%提高到180%,断裂应力从0.34 MPa提高到1.41 MPa。该材料在循环应变加载下表现出优异的网络稳定性,无明显滞后现象。二硫键的引入使材料在紫外线照射下能够自我修复,延长了其保质期。总体而言,这项工作提出了一种环境友好的方法来生产可持续弹性体,该弹性体在智能机器人、智能可穿戴技术和人机界面等应用中具有潜在用途。