Study On Synthesis Of Heat Resistant Plasticizer From Forest Products

Trioctylmaleopimarate,C₂2 tricarboxylic ester and low-molecular polyester were synthesized from modified rosin, tung oil and other inexpensive materials. It was found that they have good properties and can be used as heat resistant plasticizers.The effects of the using quantity of catalyst, ratio of reactants, reaction temperature and reaction time on the optimum reaction conditions were given..With maleopimaric acid /2-ethylhexanol(molar ratio)1∶8 and 1.0% of catalyst, under the conditions of temperature 250℃, pressure 0.5MPa and 20 hours reacting the trioctylmaleopimarate could be prepared.For the synthesis of C₂2 tricarboxylic ester, methyl eleostearate was prepared from l mol tung oil and 6 mol methanol with 0.5% KOH as catalyst could be reacted with maleic anhydride to prepared methyl eleostearate-maleic anhydride adduct, which could be esterificated with butyl alcohol to synthesized C₂2 tributyl ester. And methyl eleostearate could also be reacted with dimethyl malate or dibutyl malate to prepared C₂2 trimethyl ester or C₂2 dibutyl-monometyyl ester.The synthesis of low-molecular polyester has two stages. The first stage is the polymerization with phthalic anhydride, adipic acid and diethylene glycol (or triethylene glycol or 1,4-butylene glycol), the dosage of catalyst is 0.3%; the second stage is adding 120% 2-ethylhexanol and 0.2% catalyst to finish the esterification. The optimum ratio of reactants phthalic anhydride / adipic acid / diethylene glycol/2-ethylhexanol is 2∶2∶3∶2 and 2∶3∶4∶2.The acid value, heat weight loss,open-cup flashing point, volume electric resistivity,viscosity as well as TG curves of products were measured. The results confirmed that they could satisfy the requirements of heat resistant plasticizer. Plasticizing tests and PVC compound examinations demonstrated that they could be used to replace TOTM.,DOP and DIDP.