关键词: 木塑材料, 咖啡壳, 纳米纤维素, 聚乙烯, 球磨

Abstract:

With the continuous advancement of society, people pay more and more attention to the protection of the ecological environment. The green composite materials that can coexist harmoniously with the environment and benefit human health have received continuous attention from the scientific community. In this paper, the waste coffee husks powder was used as raw material. In order to avoid the decrease of the reinforcing effect caused by the agglomeration of the nanocellulose mixture, the urea ball milling system was innovatively used to prepare the submicron cellulose mixture (including hemicellulose and lignin) and compared with the preparation of nano-scale cellulose mixture (containing a small amount of hemicellulose and lignin). The effects of different scales of cellulose mixture on polyethylene reinforced wood powder wood-plastic composites were discussed. It showed that both the nano-scale cellulose mixture (CSNC) and the sub-micron cellulose mixture (CCMC) increased the viscosity of the wood-plastic composite at room temperature, improving the heat resistance and creep resistance of the composite. For the properties of the material, the flexural modulus of the composite increased by 35% after adding 4% PE quality CSNC, but the bending strength and impact strength decreased and the brittleness of the material increased. After adding 4% PE quality CCMC, the flexural modulus of the wood-plastic composite material was unchanged, the impact strength and bending strength were both increased by 7%, and the material strength was enhanced. In terms of water absorption, CSNC significantly increased the water absorption of the material, and the addition of CCMC had little effect on the water absorption of the material. Submicron cellulose blends were superior in improving the properties of wood-plastic composites, making preparation easier and more convenient.

Key words: wood plastic material, coffee husks, nanocellulose, polyethylene, ball milling