Study On The Green Synthesis Of 1,5-Naphthalene DiisocyanateⅠ.Synthesis Of 1,5-Naphthalene Dicarbamate

1,5-Naphthalene diisocyanate (NDI) is taken as the excellent raw material for synthesizing advanced polyurethane. Recently, the industrial production of NDI uses phosgene as raw material. This process is harmful to environment and difficult to control. Dimethyl carbonate(DMC), which is called "Green Chemicals ", can substitute phosgene for the synthesis of NDI. This route has distinct advantages, such as moderate conditions, inexpensive catalyst and unique by-product ?methanol. If it is combined with the synthesis of DMC by gas-phase oxidative carbonylation of methanol, the high atom economics process can be acquired. The key step of this method is the synthesis of 1,5-naphthalene dicarbamate (NDC) from DMC and 1,5-naphthalene diamine (NDA). So the emphasis is put on the synthesis of NDC in this thesis.The purified product of NDC was prepared and verified by IRs MS> NMR et al. The qualitative determination of main-product and partial by-product was realized. And a set of suitable and effective HPLC analysis condition was set up. As follows: chromatographic column: Kromasil?C-18, 04.6mmX 150mm, Sum; mobile phase: V(CH3OH):V(H2O)=60:40; flow speed: 0.4ml/min; wavelength of ultraviolet detector:254nm. The quantitative analysis of NDC was carried out by external standard method. The result was reliable after verification.Since the reaction was new to us , the thermodynamics analysis of the reaction system was done. The basic thermodynamic data was estimated by the method of UNIFAC and other methods. The result showed that compared with the secondary-reaction of main-product' s self-polymerization, main-reaction was in disadvantage. In order to improve the yield of NDC, it isnecessary to screen the catalysts having better selectivity , to control the proper temperature in experiment and to transform the equilibrium of the main-reaction to the production of NDC. The effective method of transforming the equilibrium of the main-reaction was distillation methanol timely and using the solvent which had the lower dissolubility of NDC .It was important to the reaction that the proper solvents and the catalysts were screened. The sequencing of the dissolubility of NDC was as follows: isobutanoK isopropanoK methanoK ethanol < acetone < DMC < acetonitrile < THF < sulfolane < dioxane < pyridine < DMSO < DMF. The sequencing of activity of catalysts was as follows: zinc oxide,basic zinc carbonate,tetrabutyl titanate < zinc chloride < lead oxide < cobalt acetate < zinc naphthenate < zinc acetate < zinc stearate.For zinc salts having better activity to the reaction, the reaction condition was optimized using zinc acetate, zinc stearate, zinc propionate and zinc trimethylacetate as catalyst. After reaction zinc acetate and zinc stearate were characterized by XRD. ZnO was founded to be produced, which had no activity to NDC synthesis. This was the reason of the deactivation of zinc acetate and zinc stearate.Zinc salts of organic acid had the better activity to NDC synthesis. The activity of zinc salts of organic acid has been compared. The sequence was as follows: zinc benzoate