| abstract |
NEW MATERIAL:A polythiol expressed by the formula (R is H or mercapto). EXAMPLE:Bis(2-mercaptoethyl thiomalate). USE:Useful as a polymerization regulator, raw material for synthetic resins, crosslinking agent, vulcanizing agent, curing agent for epoxy resins, agent for forming metallic complexes, biochemical drug and additive for lubricating oils. Especially, sulfur-containing polyurethane resins obtained by thermally polymerizing a polyisocyanate, such as xylylene diisocyanate, isophorone diisocyanate or hexamethylene diisocyanate, have a high-degree refractive index and low decomposability and excellent other various physical properties and are useful as optical parts, etc. PREPARATION:2-Mercaptoethanol is reacted with thiomalic acid, 2,3- dimercaptosuccinic acid, etc., in the presence of an acid catalyst, such as p- toluenesulfonic acid, at 60-200 deg.C while removing formed water to the outside of the system to afford the aimed compound expressed by the formula. |