Research Of Novel Polymeric Ultraviolet Absorbers

With the deterioration of ozone hole, the harm of the ultraviolet rays of the Earth’s surfacehas been widespread concerned about, and UV absorbers is undoubtedly the most direct andeffective method of preventing harmful ultraviolet rays. But now the use of small moleculesultraviolet absorbers has some shortcomings, such as the small range of UV absorption band, poordispersion in the medium, harmful to human health for easily being absorbed by the skin. To solvethese problems, a new class of polymer UV absorbers was designed and synthesized. Theirstructure was proved by IR and1H NMR. Then the UV absorption capacity, antioxidant activityand biological safety of these polymer UV absorbers were tested. In addition, the changes of theproperties of the polymer, which were caused by the increasing of molecular weight, were alsoanalyzed.2,4-dihydroxy-benzophenone (UV-0) and p-hydroxy-cinnamic acid (PHCA), the two mostcommon small molecular ultraviolet absorbers, were selected as raw materials.2-hydroxy-4-acryloy benzophenone (HAB) was synthesized by acylation of UV-0and acryloylchloride (AC). p-acryloy-methyl cinnamate (AMC) was prepared from PHMC and AC. Then theresulting monomers were copolymerization with acrylic acid (AA),3-O-allyl-1,2,5,6-di-O-isopropynylene--D-glucose (OAIG1) and3-O-acryloyl-1,2,5,6-di-O-isopropynylene--D-glucose (OAIG2) to obtained poly (HAB-co-AC)(PHA), poly (HAB-co-AA-co-AMC)(PHAA), poly (AMC-co-AA)(PAA), poly(HAB-co-OAIG1-co-AMC)(PHOA1), poly (HAB-co-OAIG2-co-AMC)(PHOA2) and poly(HAB-co-OAIG2)(PHG) and the like.By using UV-visible absorption photometer, absorption band of280-400nm was selected totest the polymer compounds. It’s found that the polymer inherited good UV absorption of themonomers. Since PHAA, PHOA and PHLA contained two different bands ultraviolet absorbersprecursor, so the absorption band was stronger than the other polymers. By the photo-antioxidanttests, it’s found the photo-antioxidant of the polymer was stronger than the other small moleculesabsorbers. The MTT assay and relative appreciation rate of the cells which were treated withdifferent concentrations of UV absorbers solutions, the results showed that the cell viability of thecells treated with glucose-based polymer was higher than others. It demonstrated thatglucose-based polymer was of good biocompatibility.In this work, a series of synthetic UV absorbers exhibited good UV absorption capacity and good photo-antioxidant property. The glucose-based polymers, PHOA and PHLA, were successfully designed and synthesized, and both of them had excellent biocompatibility. Because of OAIG2was easier polymerized than OAIG1, PHOA2was the most promising UV absorbers in the experime ntal synthetic polymers.