Polydopamine particles for next-generation multifunctional biocomposites

To support rapid advancements in the field of biocomposites, it is necessary to exploit novel fillers that are biocompatible, multifunctional and easy to obtain. In this work, polydopamine particles (PDAPs) have been reported as a filler for constructing polymer composites. PDAPs with average diameters of about 1040 and 310 nm were first prepared by a convenient oxidative polymerization of dopamine, then PDAP/poly(vinyl alcohol) (PVA) composites were prepared through a traditional solution-casting method. Measurements on the resultant composites confirmed strong interactions between the PDAPs and PVA chains and the good dispersion of PDAPs throughout the matrix. It was found that the PDAPs could promote the crystallization of PVA and, thus, greatly improve the mechanical properties of the composites. TGA results showed that both the initial and maximum decomposition temperatures of PVA were significantly increased by the addition of PDAPs. Moreover, the composites showed superior antioxidant properties and UV-shielding efficiency compared to neat PVA. The effect of particle size on the reinforcement was also evaluated. The results suggested that PDAPs could be a good candidate for use in multifunctional composites.