Poly(lactic acid)/poly (butylene succinate)/boron nitride nanosheet composites with high thermal conductivity: a novel biodegradable electronic packaging material

The electronic packaging materials are important part in electronic devices and logically become main plastic composition in electronic wastes, which are over 50 million tons annually and caused serious environmental pollution. The biodegradable polymers are excellent candidates for the environment-friendly electronic packaging material, but they are hardly thermal conductive. Thus, improving thermal conductivity of the environment-friendly polymers is the key problem of the development of novel electronic packaging materials. Two typical bio-based, biocompatible and biodegradable polyesters such as poly(lactic acid) (PLA) and poly (butylene succinate) (PBS) were complexed with boron nitride nanosheets (BNNSs), which was ionic-liquid-exfoliated from hexagonal BN, to prepare a series of PBS/BNNS and PLA/PBS/BNNS composites. The chemical structure and morphology of the composites are investigated, which proved the adsorption of ionic liquid on BNNS. The experimental results show that BNNS nanosheets are evenly dispersed in PBS and PLA/PBS matrix, and the compatibility and dispersion in PLA/PBS composite matrix are improved. The thermal conductivity of the polymer composites was increased from about 0.2 W/(m*K) of PLA or PBS to 3.52 W/(m*K) of the composites with 30% of BNNS. The flame retardancy was improved as well. These performance characteristics of composite materials provide new development ideas for future electronic packaging materials and conform to the concept of green development.