| Chinese lacquer, named as "the King of Coating", is a kind of special local product in our country. Its film is hard, heat-resistant and anti-corruptive, so the unearthed lacquerwares still keep good for thousands of years. However, it has been still an important work to improve the lacquer because of its inherent drawbacks such as being corroded by alkali, baddish weatherability, low adhesion to metal and drying only at definite temperature and humidity. The main component forming film of Chinese lacquer is urushiol which is o-dihydroxybenzene containing an unsaturated side chain. Urushiol polymer possesses good inter-soluble capability with the other resin owed to the long side chain. Urushiol and its polymer have phenolic properties because of the hydroxy in phenylene. In the first place, the hydroxy can react withthe atoms of transition element and rare element with vacant orbits. In the second place, the ortho-carbon or para-carbon of phenylene is apt to reacting with formaldehyde and amine. The functional material as urushiol metal polymer is prepared utilizing coordination reaction between urushiol or its polymer and metal compound. It is beneficial to open up some new applications and new functional materials for Chinese lacquer.On the basis of the summarizing of father's works, firstly, the reaction properties of urushiol or its polymer with PrCl3 is studied. Then, it is studied about the functions of urushiol praseodymium polymer (PUPr) synthesized utilizing the reaction between Pr3+ and phenolic hydroxy in catalyzing the polymerization of olefinic monomers, catalyzing esterification and absorbing toxic gases etc. Finally, the modificative methods to urushiol formaldehyde condensation (PUF) with alkyd, aniline and diethylen etriamine and the characteristic of product are also studied.It is studied about the synthetical condition of solvent kinds, reactive time, reactive temperature and reactant ratio etc of PUPr obtained by hot polymerization inAbstractnon-water medium. Its forming mechanism, structure characteristic and properties are illustrated by elemental analysis, IR, XPS, TG and chemical means etc. The results show that the forming of PUPr is owed to the coordination between phenolic hydroxy and Pr3+ and further cross-linking reaction of the unsaturated side chains of urushiol. For the especial out-shell electronic configurations of praseodymium element, rigidity of phenyl groups and the curl of side chains, the coordination number of praseodymium is unsaturated. As a result, PUPr possesses many aspects catalytic properties. Firstly, PUPr is reactive for catalyzing the polymerization of olefinic monomers such as butyl a -methacrylate in the presence of sodium sulfite even in atmosphere and without stirring. Secondly, PUPr can effectively catalyze esterification between phthalic anhydride and butanol etc. Thirdly, the PUPr shows adsorptive capability to toxic gases as 862 and HCHO etc. PUPr exhibits higher activity, better reusability and electivity than little molecular catalyst.The phenolic hydroxy of PUF can also coordinate with praseodymium. The structural difference between PUF and PUFPr obtained by soaking in PrCla ethanol solutionis studied by IR, X-ray diffraction analysis, DMTA and TG etc. The results show that PUF-Pr(HI) polymer coordination compound forms owed to coordination bonds between PUF and praseodymium. For seeing about the reactive abilities of diverse functional group with Pr3+, urushiol group polymers containing diverse functional group as -NH2, =C=S or -OH etc are synthesized by co-polymerizing with benzidine, acrylic resin, aniline, sulfourea and furfural. The result shows that oxygen is the best ligand to Pr3+.The condensation polymer of urushiol and formaldehyde (PUF) is an important production in the modificative study of Chinese lacquer in our country. PUF possesses excellent physico-mechanical properties and has been used practically. However, The phenyl and unsaturated side chains of urushiol group have influence on its tenacity and resistance to ul...
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