Developing carbon-storing materials through grapevine char/polybutylene succinate green bio-composites

The mass production of grapevines, an agricultural waste, has imposed burdens on farmers and the environment. This study aims to address this issue by utilizing biochar derived from grapevines (GVC) in combination with polybutylene succinate (PBS) to develop an environmentally friendly bio-composite. To enhance the compatibility between GVC and PBS, maleic anhydride grafted PBS (MAPBS) was synthesized and incorporated into the bio-composite. Moreover, surface modification of GVC was conducted using a silane coupling agent to enhance its adhesion to the PBS matrix. The effects of GVC size, MAPBS content, and surface modification on the mechanical and thermal properties of PBS were investigated. The findings indicate that GVC sieved through a 200 mesh screen exhibited a better reinforcing effect compared to GVC sieved through a 120 mesh screen. The tensile test results indicated that the incorporation of 20 wt% GVC led to a reduction in the tensile strength of PBS. However, the introduction of silane-modified GVC resulted in a substantial enhancement of tensile strength, elevating it from 33.40 MPa to 40.16 MPa. Furthermore, when the composites contained both MAPBS and a lubrication agent, the tensile strength increased even further to 41.04 MPa. The thermal analysis results of the bio-composites revealed that the addition of GVC contributed to an increase in the char yield and heat resistance of PBS. Therefore, these GVC/PBS green bio-composites not only enhance the mechanical and thermal properties of PBS but also reuse the waste grapevines, and produce the high value-added green composites with carbon-storing and biodegradability characteristics.