How To Reduce The Density Of Plastics?
Reducing the density of plastics means that the relative density of the plastics is reduced by appropriate means to suit the needs of different applications. The methods for reducing the density of plastics include foaming modification, adding lightweight fillers, and blending lightweight resins.
1. Foaming modification
Foam molding of plastic products is the most effective way to reduce their density. The addition of light addition materials and blending of light resin can only reduce the density by a small amount, and the reduction is generally only about 50%, and the lowest relative density can only reach about 0.5.
Plastic foamed products vary widely in density and have a relative density of 10-3. At present, our common PVC foaming products include PVC foam board, PVC foam sole, PVC foam tube, PVC foam profile, PVC wood plastic foam product (sliding door panel, door sleeve line, wall panel, etc.), PVC hair Soaking mats, etc.
2. Blending lightweight materials
Add low-density plastic blends, such as PE, PP, CPE, ABS, MBS; there is also a lightweight filler: wood flour, which is fine fiber of wood, very light. But there are certain limitations, according to Use different methods yourself.
3. Add lightweight filler
Such as PE, PP, CPE, ABS, MBS. Or wood powder, hollow glass beads, and the like. For example, the micro-bead filler microstructure, this method makes the density reduction smaller, generally the lowest can be reduced to a relative density of 0.4-0.5. The relative density of the fillers is larger than that of plastics, and the types of fillers with a relatively low density of plastics are only as follows. In addition, the filler is better in calcined clay, the specific gravity is smaller than that of calcium powder, and the price is not much different from that of light calcium. The oil absorption value is equivalent to that of calcium powder.
1) The glass hollow microspheres (drift beads) have a relative density of 0.4-0.7, which is mainly used for thermosetting resins;
2) The relative density of the phenolic microbeads is 0.1.
(2) Organic fillers
1) Cork powder has a relative density of 0.5 and an apparent density of 0.05-0.06;
2) The relative density of fiber dust and cotton chips is 0.2-0.3;
3) Fruit shell crops such as straw flour, peanut flour and coconut shell powder.
4) such as plasticizers, liquid internal and external lubricants, etc. The density of pure polyvinyl chloride is 1.4 g/cm3, and it is 1.19~1.35 when plasticized polyvinyl chloride (about 40% plasticizer).