The polylactic acid (PLA) nanofiber membranes reinforced with hyperbranched PLA‐modified cellulose nanocrystals (H‐PLA‐CNCs) were prepared by electrospinning. The H‐PLA‐CNCs and the nanofiber membranes were researched by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), and dynamic mechanical analysis (DMA). The outcomes embodied that the cellulose nanocrystals (CNCs) could be successfully improved by the hyperbranched PLA, which would offer powerful CNCs/matrix interfacial adhesion. Thus, the mechanical and shape memory properties of PLA can be improved by adding the H‐PLA‐CNCs. In particular, when the addition of H‐PLA‐CNCs was 7 wt%, the tensile strength and an ultimate strain of PLA composite nanofiber membranes was 15.56 MPa and 25%, which was 228% and 72.4% higher than that of neat PLA, respectively. In addition, the shape recovery rate of the PLA/5 wt% H‐PLA‐CNCs composite nanofiber membrane was 93%, which was 37% higher than that of neat PLA. We expected that this present study would provide unremitting efforts for the development of more effective approaches to prepare biology basic shape memory membranes with high mechanical properties.

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Nanotechnology is gradually applied to the preparation of heat dissipation materials with the miniaturization of electronic devices. Electrospinning technology has received extensive attention due to its unique advantages in constructing continuous nanofibers. In this work, uniaxial-polyvinyl alcohol/nanodiamond (U-PVA/ND) and coaxial-polyvinyl alcohol/nanodiamond (C-PVA/ND) composite fiber films with different microscopic morphologies were constructed by uniaxial and coaxial electrospinning. The results show that the thermal conductivities of U-PVA/ND and C-PVA/ND composite fibers with 60 wt % ND content are 71.3 and 85.3 W m–1 K–1, respectively, which are 171.2 and 205.1 times greater than that of the pure PVA fiber film. In addition, the maximum thermal decomposition temperature (T max) and volume resistivity of the C-PVA/ND composite fiber film were 364.3 °C and 2.29 × 1015 Ω·cm, respectively, demonstrating the excellent thermal stability and electrical insulation of the composite fiber film. This experiment results provide strong evidences of electrospinning technology for the preparation of highly thermally conductive composites. So, thermally conductive films can be used as the outer layer of electronic components to accelerate their heat dissipation and extend their service life.

Electrospinning preparation of perylene-bisimide-functionalized graphene/polylactic acid composite films with shape-memory properties.