Views:16 Author:Vera Publish Time: 2018-07-25 Origin:Site
Reducing the density of plastics means that the original relative density of plastics is reduced by appropriate means to meet the needs of different applications.
The methods of reducing the density of plastics include foaming modification, adding light filler and blending light resin.
Foaming molding is the most effective way to reduce the density of plastic products. However, by adding light material and blending light resin, the density decrease is only about 50%, and the lowest relative density can only reach 0.5 or so. The density of plastic foamed products varies in a wide range, the lowest relative density can reach 10-3. At present, our common PVC foaming products include PVC foaming board, PVC foaming sole, PVC foaming tube, PVC foaming material, PVC wood plastic foaming product (door moving board, door sleeve, wall board, etc.).
2. Adding light filler
For example, PE/PP/CPE/ ABS/ MBS, such as wood powder, hollow glass microspheres, etc., all above make the density decrease slightly, and the lowest density can be reduced to about 0.4-0.5 in general. The relative density of fillers is larger than plastic, and only a few kinds of fillers with smaller relative density than plastics. In addition, calcined clay is a better filler, which specific gravity is smaller than calcium powder, the price is not different from light calcium, the oil absorption value is equal to calcium powder.
a. The relative density of glass hollow microspheres is 0.4-0.7, which is mainly used in thermosetting resins.
b. The relative density of phenolic beads was 0.1.
2) Organic fillers
a. Cork powder, the relative density is 0.5 and the apparent density is 0.05-0.06;
b. Fiber dust, cotton dust, the relative density is 0.2-0.3;
c. Husk crops such as rice straw powder, peanut powder and coconut shell powder and so on.
d, Such as plasticizer, liquid lubricant, etc., the density of pure PVC is 1.4g/cm³, and the density of plasticized PVC (about 40% plasticizer) is 1.19 ~ 1.35;
3. Blending light resins
Add low density plastic blends, such as PE/PP/ CPE/ABS/MBS; or a lightweight filler: wood powder (fine fibers of wood). But also have certain limitation, can adopt different method according to oneself.