Photostabilizing effectiveness of new HALS produced by isocyanation of hindered piperidine derivatives

Abstract

Twelve new hindered-amine light stabilisers (HALS) were prepared by isocyanation of the hindered piperidine derivatives 2,2,6,6-tetramethyl-4-piperidinol, 1,2,2,6,6-pentamethyl-4-piperidinol and 4-amino-2,2,6,6-tetramethylpiperidine, by using dibutyltin dilaurate as catalyst. Test results show that these new HALS are effective light stabilisers, some of them comparable to a commercial HALS, Tinuvin-770. Reactions of these hindered piperidines with isocyanates proceed at temperatures varying from room temperature to 80°C and take less than 30 min to complete. The reactions are quantitative and no toxic byproducts are produced. © 1998 Elsevier Science Limited. All rights reserved.