Rare Earth - Uv Absorbers Complexes Stabilizing Effect Of The Polymer Light

Rare earth complexes of UV absorber "Dibenzoylmethan(HDBM), Benzoyl-acetone(HBA), 2-hydroxy-4-octoxyl-benzophenone(HOBP) and 2-hydroxy-4-meth-oxyl-benzophenone(HMBP)" have been synthesized. The physical and chemical property such as UV absorption, heat resistance, light fastness and soluability and photostabilization to polymer etal of those rare earth complexes have been discussed. And the photostabilization mechanics of those rare earth complexes were speculated. The main results and conclusion are:(1) By comparing the appearance, melt point, and Infra-red spectrum of the synthesized products, the method that rare earth complexes whose composition are RE(DBM)3(H2O)1-2, RE(BA)3(H2O)1-2, RE(MBP)3, RE(OBP)3 can be synthesized by HDBM, HBA, HOBP, HMBP react with rare earth chloride or nitrate in ethanol-water solution were confirmed, and the formed RE-O coordinate band have some covalent band character.(2) The influence on UV absorption character and light fastness property caused by the process of UV absorber change to rare earth complexes are not obvious, but the heat resistant ability has gotten obvious improvement, and the solubility in polar sovent such as ethanol etal is reduced obviously, But still have certain solubilities in nonpolarity solvent such as benzene and ring own alkane etal..(3) The test of photo-stabilization to polymer of rare earth - UV absorber complexes have been made in laboratory accelerate experiment, results showed that by forming rare earth complexes can improve the photostablization efficiency to polymer of UV absorber, the highest improvement effect will be triple to that of UV absorber. For same rare earth ions, the improvement effect are HOBP >HMBP> HDBM > HBA; while for same UV absober, the improve effect changed regularly as "Four Group Effect" with ith increase of the atomic number of rare earth element.(4) The fact the photostablization to polymer of rare earth-UV absorber complexes has "Four Group Effect" regularity disclosured that there will be exist some relationship between the photostabilization of rare earth complexes and coordination, while The influence on UV absorption character and light fastness property caused by the process of UV absorber change to rare earth complexes are notobvious. And rare earth complexes have no obvious oxidation-reduction and free radical seize ability, so the function mechanics of photostabilization to polymer of rare earth UV absorber complexes can be speculated that those complexes may coordinated with photo-senstive group on polymer band such as carbonyl or/and hydroperoxides etal, so concentration of complexes besides photo-senstive group can be accumulated that not only decreased the light absorption of photo-senstive group but also increased the quenching effect to excitation state of rare earth complexes.