How to correctly understand what polyurethane resin is?

a polymer compound containing a large number of carbamate chain links in its molecular structure is called polyurethane resin. it is produced from isocarbamate and active hydrogen-containing compounds. coatings that use polyurethane resin as the main film-forming substance are called polyurethane coatings. in its coating film, in addition to containing a large number of urethane…