How to Identify different kinds of plastic?
1. Polyvinyl chloride (PVC)
Appearance: (same as polycarbonate)
Flammability: flame retardant. It burns yellow in the flame, the edge of the flame is green, white smoke; there is a softening phenomenon. A burnt smell can be smelled.
2. Amino resin (UF urea/formaldehyde; MF melamine/formaldehyde)
Appearance: (including filler) hard.
Flammability: flame retardant. It is bright yellow when burned in the flame; there are charring, expansion and cracking phenomena. Can smell ammonia, formaldehyde, fishy smell.
3. Polyethylene (PE)
Appearance: translucent to opaque, hard; transparent film.
Flammability: combustible in the flame, slowly extinguishes or continues to burn after leaving the flame. When burning, the upper end of the flame is yellow, and the lower end is blue; there are melting and dripping phenomena. Can smell paraffin.
4. Polypropylene (PP)
(Appearance and flammability are the same as polyethylene)