Effect of colorants on interfacial compatibility in wood flour/poly (β-hydroxybutyrate valerate) composites

Abstract

ABSTRACT In order to study the effect of the colorants on interfacial compatibility between wood and polymer in wood flour/Poly (β-hydroxybutyrate valerate) composites (WPHBVs), three kinds of colorants (white, yellow and red colorants) were added respectively to color the WPHBVs. The results showed that the bending strength and elastic modulus of the WPHBVs increased first and then decreased with the increase of colorant content. When the amount of white, yellow and red colorants was 3%, 2% and 3%, respectively, the WPHBVs showed the best performance. The bending strength increased by 21%, 33% and 18% respectively, and the elastic modulus increased by 26%, 37% and 21% respectively. The SEM micrographs of the WPHBVs revealed that some of the cracks and grooves in the wood fibers were coated with the dispersed colorant, which improved the mechanical properties of the WPHBVs. However, there were no new obvious characteristic peaks in the FT-IR spectra of the WPHBVs, indicating that the colorants only facilitated thorough mixing of wood flour with PHBV. The addition of these colorants improved the compatibility between wood flour and PHBV, and significantly improved the bending strength and elastic modulus of the WPHBVs.