The main differences between the properties of thermosetting resins and thermoplastic resins are: ① different solvent resistance. Thermoplastic resins produced by the polymerization method have strong resistance to organic solvents, so most synthetic fibers can be dry-cleaned, but only spandex has poor solvent resistance; thermosetting resins such as buttons, resin beads, and coatings are generally not dry-cleanable. Therefore, various organic solvents, such as tetrachloroethylene, carbon tetrachloride, gasoline, acetone, banana water, etc., are generally packaged in glass bottles or iron drums instead of plastic drums, which is why thermosetting resins are not resistant to solvents . The situation that thermosetting resin is not resistant to solvents is more complicated. Not every solvent can dissolve every kind of thermosetting resin. Laundry employees know that if they work for a long time to remove stains, alcohol has a poor ability to dissolve resin, but it can dissolve plexiglass. In the past, the universal glue used by people was made of alcohol to dissolve plexiglass. The lamp glass is plexiglass. If it is dirty, wipe it with alcohol. Not only can it not be bright, but it will become more turbid and unclear. Check carefully that the surface has been dissolved. ②The heat resistance is different. Thermosetting fibers have better heat resistance than thermoplastic fibers. Once the thermosetting resin is cured, it will no longer soften or flow under pressure and heat. Thermoplastic resin has the properties of softening by heating and hardening by cooling, even if heating and cooling are repeated multiple times, this performance can be maintained. ③Different uses. Thermosetting resins are mainly used to manufacture reinforced plastics, foam plastics, various electrical molding compounds, cast products, etc., and a considerable amount is used for adhesives. Thermoplastic resins are widely used, and 2/3 of the plastics used in construction belong to thermoplastic resins. Synthetic fibers are an important category of thermoplastic resins.