Simultaneous improvement of mechanical properties and electromagnetic interference shielding performance in eco-friendly polylactide composites via reactive blending and MWCNTs induced morphological optimization

• Published in: Composites. Part B, Engineering Vol. 178; p. 107452
• Main Authors: Fang, Huagao, Wang, Shenglin, Ye, Wujin, Chen, Xu, Wang, Xiaohong, Xu, Pei, Li, Xueliang, Ding, Yunsheng
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.12.2019
• Subjects: Electrical conductivity; Electromagnetic interference shielding; Polylactide nanocomposite; Toughness; Electromagnetic interference shielding; Polylactide nanocomposite; Toughness; Electrical conductivity
• ISSN: 1359-8368; 1879-1069
• DOI: 10.1016/j.compositesb.2019.107452

Poly (l-lactide) (PLLA) based ternary nanocomposites were fabricated by introducing in situ crosslinked poly(ethylene glycol) diacrylate (CPEGDA) as the rubbery toughening modifier and multiwall carbon nanotubes (MWCNTs) as the conductive fillers. Due to the incorporation of MWCNTs, the domain size of CPEGDA became smaller and MWCNTs were selectively distributed in PLLA continuous phase, facilitating to balance the stiffness and toughness. Rheological investigation showed that the formation of a double network of CPEGDA and MWCNTs resulted in constrained molecular mobility, thus greatly increasing the modulus and viscosity at low frequencies and long-time relaxation strength. The low percolation threshold of MWCNTs in electrical conductivity was found to be 0.19 vol% and the electromagnetic interference shielding effectiveness (EMI SE) of 26.4 dB was achieved with incorporating 2.4 vol% of MWCNTs. This work could provide a novel way to fabricate PLLA based eco-friendly nanocomposites with simultaneous superior mechanical properties and excellent EMI shielding performance.