Jiangxi Aote Technology Co., Ltd. used calcium carbonate, wollastonite, and talc to modify the PE wood-plastic composites. The mechanical properties of the wood-plastic composites were investigated. The effects of density and water absorption provide important references for the design, production and application of wood-plastic composite products.

Talc powder c: AT-1500 d: AT-2000

SEM photos of different inorganic powders

The picture above shows the SEM photos of different types of inorganic powders, all of which are 5000 times magnification. It can be seen from the figure that the calcium carbonate CC-0023 and CC-0026 have an irregular cubic structure, and the particle size of CC-0026 is smaller than that of CC-0023. The talcum powder AT-1500 and AT-2000 both have a layered and flake structure, and the particle size of AT-2000 is smaller than that of AT-1500. Wollastonite powders AT-0023 and AT-0026 both have a needle-like, massive structure, and the particle size of AT-0026 is smaller than that of AT-0023.

The above picture shows the flexural strength of PE wood-plastic composite materials after adding different types of inorganic powders (calcium carbonate, talc powder, wollastonite powder). It can be seen that with the gradual increase in the content of inorganic powder, the flexural strength of PE wood-plastic composites first increases and then decreases. Under the same additions of different inorganic powders, wollastonite has the largest flexural strength, followed by talc and calcium carbonate. In the case of the same type of inorganic powder filling, the inorganic powder with a smaller particle size has a greater contribution to the flexural strength of the PE wood plastic composite material, because the inorganic powder with a small particle size can just fill the wood powder particles In the gap between them, the density of the PE wood-plastic composite material is increased, the stress of the PE wood-plastic composite material is increased, and the bending strength is improved.

It can be seen from the figure that with the gradual increase in the content of inorganic powder, the impact strength of PE wood-plastic composites first increases and then decreases; the impact of talc AT2000 in the case of the same filling amount of different inorganic powders The strength is the largest, followed by wollastonite AT-0023 and AT-0026, and calcium carbonate CC-003 and CC-0026 are slightly worse. This is because talc has a flaky structure and wollastonite has a needle-like structure. The structure greatly improves the impact properties of the material; the impact strength of AT-2000 is greater than AT-1500, which indicates that the silicon content of talc has an impact on the mechanical properties of the material. The larger the silicon content, the better the mechanical properties for reinforcement ; In the case of the same type of inorganic powder filling, the PE wood-plastic composite material filled with the inorganic powder with a small particle size has a large impact strength.

It can be seen from the figure that as the content of inorganic powders gradually increases, the density of PE wood-plastic composites gradually increases; the same is true for different inorganic powder filling conditions, and the calcium carbonate CC-0023 and CC-0026 filled The density of PE wood-plastic composites is larger. This is because calcium carbonate has an irregular cubic structure and is easier to fill in the spaces between wood powder particles, thereby increasing the density of PE wood-plastic composites. In the case of bulk filling, the finer the particle size of the inorganic powder, the denser the PE wood-plastic composite material filled.

It can be seen from the figure that with the gradual increase in the content of inorganic powder, the water absorption of PE wood-plastic composites at 24h gradually decreases. This is because the water absorption of wood powder is greater than that of inorganic powder. The relative content of wood powder decreases, and the water absorption rate also decreases. Among them, with the same additions of different inorganic powders, wollastonite has the lowest water absorption rate in PE wood-plastic composites, which is most beneficial to improve PE wood-plastic composites The material's water resistance is followed by talc and calcium carbonate.

It can be seen from the figure that with the gradual increase of the content of inorganic powder, the Shore hardness of PE wood-plastic composites gradually increases; when the same addition amount of different inorganic powders, the wollastonite-filled PE wood-plastic composite The hardness of the material is the largest, followed by calcium carbonate, and the hardness of the talc is the smallest. This is because the hardness of the inorganic powder itself has a great influence on the hardness of the composite material. In addition, it can be found that in the case of the same type of inorganic powder filling, the hardness of the PE wood-plastic composite material filled with the finer particle size of the inorganic powder is greater.

It can be seen from the figure that as the content of inorganic powder gradually increases, the linear thermal expansion coefficient of PE wood-plastic composites gradually decreases; when different inorganic powders are filled, the linear thermal expansion of PE wood-plastic composites filled with wollastonite The coefficient is the smallest, followed by talc, and the linear thermal expansion coefficient of calcium carbonate is the largest. This is because as the content of the inorganic powder increases, the relative content of the wood powder decreases, and the linear thermal expansion coefficient of the wood powder is larger than that of the inorganic powder, so the linear thermal expansion coefficient shows a tendency to decrease.

1. As the amount of inorganic powder added gradually increases, the impact strength and flexural strength of PE wood-plastic composites both show an upward trend and then decrease; wollastonite has the most advantage in improving the flexural strength of PE wood-plastic composites. Talcum powder performs the best in improving the impact strength of PE wood-plastic composites; the density and hardness of PE wood-plastic composites have gradually increased, and the 24-hour water absorption and linear thermal expansion coefficient of PE wood-plastic composites have gradually increased reduce;

2.Compared with the other two kinds of fillers, the density of calcium carbonate-filled PE wood-plastic composites is relatively large, and the hardness of wollastonite-filled PE wood-plastic composites is the largest, and at the same time it is most beneficial to reduce the water absorption of PE wood-plastic composites. And linear thermal expansion coefficient.