A Bioinspired Polymer-Based Composite Displaying Both Strong Adhesion and Anisotropic Thermal Conductivity

摘要

The integration and functionality of high-power electronic architectures ordevices require a high strength and good heat flow at the interface. However,simultaneously improving the interfacial bonding and phonon transport ofpolymers is challenging because of the tradeoff between the cross-linkedflexible chains and high-quality crystalline structure. Here, a copolymer,poly(dopamine methacrylate-co-hydroxyethyl methacrylate P(DMA-HEMA)is designed and synthesized, inspired by the snail and mussel adhesion.The copolymer achievs a high surface adhesion up to 6.38 MPa owing tothe synergistic effects of hydrogen bonds and mechanical interlocking.When the copolymer is introduced into vertically aligned carbon nanotubes(VACNTs), the catechol groups in P(DMA-HEMA) formed strong bondingwith the nanotubes through π-π interactions at the interface. As a result, theP(DMA-HEMA)/VACNTs composite shows a high through-plane thermalconductivity (21.46 W m~(?1) K~(?1)), an in-plane thermal conductivity that is3.5 times higher than that of pristine VACNTs, and an extremely low thermalcontact resistance (20.27 K mm2 W~(?1)). Furthermore, the composite formsweld-free high-strength connections between two pieces of various metals tobridge directional thermal pathways. It also exhibits excellent interfacial heattransfer capability and high reliability even under zero-pressure conditions.