Effects of inorganic pigments on color and accelerated weathering of wheat straw fiber /polyvinyl chloride composites

The application of wood-plastic composites (WPCs) in outdoor settings has led to growing emphasis on their aesthetics and weathering. Therefore, it is necessary to study the effect of inorganic pigments on the weathering behavior of WPCs. In order to reveal the effect of inorganic pigments on the aging process of composites, wheat straw fiber/polyvinyl chloride composites (WSFPs) incorporating inorganic pigments were prepared, and accelerated weathering tests of the different colored WSFPs were carried out, and the changes of chemical structure, color stability, three-dimensional morphology, mechanical properties and physical properties of composites during weathering were investigated. The results showed that WSFPs with inorganic pigment showed high color stability and weather resistance during accelerated weathering. After weathering for 480 h, the color change exhibited by WY was the least, only 13.00, and its tensile, flexural and impact properties decreased by 5.14%, 8.72% and 3.10%, respectively. This study demonstrates that inorganic pigments not only enhance the aesthetics of WSFPs through coloration, but also effectively improve their weather resistance. Inorganic pigments help maintain the vibrant color and structural integrity of the material during long-term use.