PVC stabilizers mainly include lead salts, fatty acid metal salts, and organic tin.
1. Lead salts stearate include all lead salts except lead soaps, most of which contain a base, namely lead monoxide (PbO). Lead salt stabilizers are the most commonly used and most effective stabilizers for PVC, but they are not suitable for transparent products; lead salt stabilizers have gradually withdrawn from the market in recent years due to their high toxicity.
2.Most of them are salts of metals (barium, cadmium, lead, zinc, calcium, magnesium) of fatty acids (lauric acid, stearic acid, etc.). Its general formula is (RCOO)nM. In addition to being able to react with HCl, its main function is to replace active allyl chlorine atoms. The stabilizing effect of metal soaps is general, transparent, toxic or non-toxic, and is rarely used alone. It is generally used in combination and is mainly used in soft products.
3. The general formula of organic tin is RmSnY4-m (R is an alkyl group, and Y is a group connected to Sn through an oxygen atom or a sulfur atom). According to the difference of Y, there are three main types of organotin stabilizers: fatty acid salt type, maleate type and thiolate type. Organotin has good stabilizing effect, is suitable for transparent products, and has non-toxic specifications; but its price is relatively expensive.