In recent years, various polypropylene materials (PP) have been widely used in the automotive industry, construction industry and other fields due to their low density and corrosion resistance
In addition to reducing composite cost, mineral fillers can also help improve mold shrinkage, stiffness, and wear resistance, which are indicators that thermoplastics need to improve today
Wollastonite is a chain metasilicate mineral with a needle-like structure with high aspect ratio and strong anisotropy.
It is a promising Thermoplastic Reinforcement Coatings Online at coatingol.
There are hydrophilic groups on the surface of natural wollastonite, which has obvious hydrophilicity and oleophobicity.
Therefore, the compatibility between wollastonite and PP is poor, and it is difficult to form a good combination.
Direct filling in PP cannot effectively improve its performance
Ran Xia et al.
modified wollastonite with silane coupling agent KH-570 and stearic acid composite modifier, filled the modified wollastonite in polypropylene, and studied the wollastonite/polypropylene composite The properties of the material, the results show:
(1) The composite modification of wollastonite by stearic acid and silane coupling agent KH-570, the optimal process conditions are: the total mass fraction of composite modifier is 2%, the mass ratio of stearic acid to KH-570 It is 1:1, the modification time is 1h, the temperature is 60°C, and the stirring speed is 300r/min
(2) When the filling amount is 45%, the flexural modulus of the modified wollastonite-filled polypropylene composite material is 1531.
54 MPa, the flexural strength is 30.
42 MPa, and the tensile strength does not change significantly
(3) Compared with the unmodified wollastonite, the modified wollastonite and polypropylene have a better bonding interface, indicating that the modification is beneficial to improve the mechanical properties of the modified wollastonite/polypropylene composite