Study of thermally conductive polyurethane/boron nitride composite fibers: Fabrication, characterization, properties and textile applications

Abstract Polyurethane resin (PU) and boron nitride (BN) are used to develop a series of boron nitride/polyurethane (BN/PU) composite fibers by a wet‐spinning method. The thermal conductivity of the composite fibers was improved by blending modified thermally conductive particles with polymer. The improvement of thermal conductivity depends largely on the interfacial effect between them. The results show that PU composite fabric filled with BN functionalized with polyethylenimine and glutaraldehyde (GPBN/PUF) has a high thermal conductivity, revealing an increase of 226% compared to the PU fabric. The GPBN/PUF fabric can reduce the simulated skin temperature by 2.3°C compared with conventional cotton fabric. Additionally, the as‐prepared GPBN/PUF fabric possesses good mechanical stability and washability. This work provides a strategy for developing flexible heat‐conducting fabric. Highlights The stability of the PEI coating formed on the BN surface was significantly improved by GA cross‐linking. The composite fiber fabric has improved thermal conductivity and good mechanical properties. The composite fiber fabric can dissipate heat quickly in practical applications.