1, 4-butanediol is widely used. In the United States and Western Europe more than half of the production of tetrahydrofuran, followed by the production of γ-butyllactone and polybutylene terephthalate, the latter is rapidly developing engineering plastics; 1, 4-butanediol is used as chain extender and polyester raw material to produce polyurethane elastomer and soft polyurethane foam. The esters of 1, 4-butanediol are good plasticizers for cellulose, polyvinyl chloride, polyacrylate and polyester. 1, 4-butanediol has good hygroscopicity and flexibility, can be used as gelatin softener and absorbent, cellophane and other non-paper primer. It can also prepare N-methylpyrrolidone, n-vinylpyrrolidone and other pyrrolidone derivatives. It is also used in the preparation of vitamin B6, pesticides, herbicides and solvents, plasticizers, lubricants, humidifiers, softness, adhesives and brighteners for the electroplating industry.