Design, Synthesis And Characterization Of Hindered Amine Light Stabilizers

Hindered amine light stabilizers are always one of the most attractive fields of stabilizers due to their excellent photo-stabilization efficiency. The synthetic technologies of three hindered amine light stabilizers were established, the reason for the insoluble side products formed in the production of polymerized hindered amine light stabilizers were studied, and a series of novel hindered amine light stabilizers with antibacterial properties were designed and synthesized in this present paper.1. Based on the investigation of the transesterification between dimethyl sebacate and 1,2,2,6,6-pentamethyl-4-piperinol, the synthetic technologies of Tinuvin292 and Tinuvin 765 were established. The two kinds of hindered amine light stabilizers were obtained in the yield of 93.3% and 92.4% respectively and qualified as the advanced level of the kindred overseas products.2. The synthetic technology of Tinuvin123 was studied and established. Using 2,2,6,6-tetramethyl-4-piperinol as the starting material, the product was synthesized successfully through oxidation, free-radical reaction and transesterification in overall yield of 57.6%. According to the characterization of the obtained Tinuvin123 by 1H NMR, its composition was identical to those of the kindred overseas products.3. This dissertation theorized the structures of the insoluble side products formed in the production of Cyasorb3346 and Chimassorb944 according to the investigation of their synthetic technologies. Based on this hypothesis, five compounds were synthesized and their structures were confirmed by 1H NMR, 13C NMR and ESI-MS. The by-products obtained during the production of Cyasorb3346 and Chimassorb944 were separated and purified, their spectra were recorded, indicating that 5a-b were the main insoluble by-products during the production of Cyasorb3346 and Chimassorb944.4. This dissertation introduced an N-halamine structure to a reactive-HALS molecule resulting in a new type of hindered amine light stabilizers capable of providing both photo-stabilization and antimicrobial activity. Their structures were characterized by FT-IR, 1H NMR, and ESI-MS. The compounds were tested for antibacterial activity against Candida albicans, Staphylococcus aureus, and Escherichia coli. At a concentration of 0.05%, these compounds all exhibited satisfactory antibacterial activity against all the three types of bacteria.