| Turpentine is one of the world's most abundant renewable natural resources; it is particularly rich in China.α-pinene andβ-pinene is the main component of turpentine. The use of turpentine is extensive, but more applications are prepared terpene resin by polymerization. Terpene resin, usually carried out by cationic polymerization of terpene monomers, is low molecular weight and linear thermoplastic resin.This paper usedα-pinene orβ-pinene in turpentine as materials, Keggin heteropolyacids as catalyst, under definite reaction conditions, prepared colorless terpene resin. The main research methodes and results are as bellow:1) Colorless terpene resin have prepared by cationic polymerizaton ofβ-pinene with phosphotungstic acid as catalyst. Through the study of different reaction conditions, such as reaction temperature, reaction time, catalyst amount, catalyst calcination temperature, catalyst calcination time, solvent polarity. At the same time, compared the performance of variety of Keggin heteropolyacid on the conversion rate and polymer yield. Further, In order to acknowledge this new catalysis reaction, special techniques of FT-IR, 1H-NMR, XRD, and XPS were used to characterize catalyst before and after reaction and it showed that the crystal structure of the heteropoly anion was not destroyed during reaction, the HPAs played two important roles as: polymerization initiator, and the counter-anion of the growing cation center. The last the possible course had put forward.The experimental results showed that among the catalysts tested, PW12 dehydrated at 200°C for 2h displayed the best catalytic performance. Under optimized reaction conditions, that is temperature at -10℃, usage of catalyst is 5% weight of pinene, reaction time is 18h, the overall pinene conversion was up to 96.53%, the polymer product yield was obtained 60.85%, the colorless terpene resin of molecular weight is 815 and molecular weight distribution is 1.3 could be obtained.2) Light yellow terpene resin have prepared by cationic polymerizaton ofα-pinene with silicotungstic acid as catalyst. Through the study of different reaction conditions, such as reaction temperature, reaction time, catalyst amount, catalyst calcination temperature, catalyst calcination time, solvent polarity, we obtained the optimal recation conditions. The catalyst before and after the reaction, isomerization by-products andα-pinene resin were characterized as well.3) The heteropolyacid contained manganese, chromium, molybdenum, vanadium have been prepared. FT-IR, XRD and ICP characterizations revealed that the compounds synthesized in the present work have Keggin structure. The catalytic performances of the heteropolyacids were also investigated. The result showed that the heteropoly acids have catalytic properties. The yield of colorless terpene resin is up to 43% under the optimal reaction conditions.4) A series of quaternary ammonium phosphotungstates have synthesized. The phosphotungstates were characterized by means of FT-IR. The influences of different degree of substitution of quaternary ammonium phosphotungstate onβ-pinene cationic polymerization have been studied. The result indicated that the catalytic activity of cetyltrimethylammonium tungstophosphoric is higher. The data from different reaction conditions indicated that the following conditions can benefit forβ-pinene cationic polymerization: The solvent is methylene chloride, the degree of substitution of quaternary ammonium phosphotungstate is 0.5. The yield of resin could be achieved 53.03%.
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