Preparation of high-performance waste polyvinyl chloride/paper biocomposites by hot pressing

Abstract Developing novel biocomposites from waste paper and plastic products contributes to achieving global sustainable development goals. In this paper, the polyvinyl chloride (PVC) powder and paper floc were mixed in different proportions and subjected to dry hot molding (180 ℃, 73.8 MPa, 1 h) to prepare waste PVC/paper biocomposites with excellent performance. The characterisation results show that the paper flocs treated with 3% NaOH had the best comprehensive mechanical properties (both tensile and flexural strengths of up to 183.98 MPa and 66.60 MPa, respectively). PVC/paper biocomposites generally show a downward trend in water absorption as the proportion of PVC powder in the composite increases. It was found that the rate of water absorption was only 8.29% when the ratio of PVC powder to 3% sodium hydroxide treated paper floc was 7:3. As can be seen from the SEM image of the PVC/paper biocomposite, the PVC powder fills the gap between the multiple paper fibres, thus resulting in a higher mechanical strength for the biocomposite. Based on the findings, a novel and practical method for recycling paper and plastic product wastes is demonstrated, which is in line with the development concept of low-carbon environmental protection and sustainable economic growth advocated globally.