Recyclable, Self-Healing, and Highly Thermal Conductive Natural Rubber Nanocomposites Enabled by a Dynamic Covalent Network with Carboxylated Boron Nitride Nanosheets
Chang Gong, Junxia Guo, Peikuan Xu, Jin Lv, Ruiguang Li, Chengjie Li
Abstract
It is of great significance for saving resources and protecting the environment to endow rubber with excellent recycling ability. Recyclable and self-healing ENR/BN-COOH/GO nanocomposites were prepared through dynamic covalent crosslinking between epoxidized natural rubber (ENR) and carboxylated boron nitride (BN-COOH), and graphene oxide (GO) was used as a reinforcing filler. The constructed dynamic β-hydroxyl ester bond between ENR and BN-COOH resulted in the remarkable enhancement of interfacial interaction and effective energy dissipation, which contributed to good mechanical properties of the nanocomposites, increasing by 116 and 79% in comparison with ENR and ENR/GO, respectively. An exchangeable β-hydroxyl ester bond could regulate a network topology structure via a transesterification reaction at the interface, endowing ENR with desirable recycling and self-healing ability. Moreover, the significant improvement of thermal conductivity for ENR/BN-COOH/GO nanocomposites was achieved, reaching 2.853 W/(m·K) at only 6 wt % BN-COOH content, indicating the formation of effective thermal conductive paths via the β-hydroxyl ester bond and hybrid thermal conductive network of BN-COOH/GO. Meanwhile, the thermal conductivity of recycled samples still maintained a high level due to the construction of the stable thermal conductive network. Such a facile strategy exhibits a promising perspective in preparing recyclable and highly thermal conductive rubber nanocomposites for applications in efficient thermal management fields.