Highly thermally conductive electrospun stereocomplex polylactide fibrous film dip-coated with silver nanowires

Abstract

Polymer fibers have demonstrated excellent thermal conductivity (λ) owing to the extensive orientation of the molecular chains, and the enhanced interaction of molecular chains is believed to be able to improve the λ of polymers. Herein, stereocomplex polylactide (sc-PLA) fibrous films were fabricated through a combination of improved orientation of the molecular chains by electrospinning and enhanced molecular chain interactions of enantiomeric poly(L-lactide) (PLLA) and poly(D-lactide) (PDLA). The results illustrated the thermal conduction properties of annealed sc-PLA fibrous films were much better than those of bulk PLLA samples, and were further improved compared with that of pure PLLA fibrous film with only homocrystallites. AgNWs could enter the interior of the whole annealed sc-PLA fibrous film by a facile dip-coating process, and the bridging of AgNWs with sc-PLA fibers further prompted the formation of a thermally conductive network. The resulted sc-PLA/AgNWs fibrous films showed a high λ of 5.95 W/(m⋅K) with only 0.58 vol% of AgNWs, which was 2.5 times that of pure annealed sc-PLA fibrous film. The highly thermally conductive sc-PLA/AgNWs fibrous film was highly potential to be used as thermal management materials.