Synthesis Of Dimer Acid Based Polyester Polyol And The Properties Of Its Thermoplastic Polyurethane Elastomer

In the paper, dimer acid, which was from natural oil processing production, was used as the main material, together with adipic acid and neopentyl glycol, adipic acid and 1,4-butanediol to synthesize two kinds of polyester polyols, the relative molecular weight of which is 2000, under the protecting of N2. Thermoplastic polyurethane elastomer was synthesized, by using the polyester polyol synthesized in the experiment, MDI, chain extender ethylene glycol as the main materials, through prepolymers way.According to the polyester polyol's reaction theory, polymerization realation degree and materials proportion, the paper determine the method to synthesize polyester polyol.Measuring the acid value, hudroxylvalue, molecular weight, moisture, relative weight, weight average molar mass, molecular weight distribution and viscosity of the production.Characterizing the construction of the production by using infrared spectrum and nuclear magnetic resonance way.The relative molecular weight, acid value and hudroxyl value were considering as the most important factors.Alcohol acid ratio, the highest reaction temperature, reaction time, temperature retention time, catalyst and catalyst dosage were studied to know their effects on the reaction. Using the L9(34) orthogonal experiment method to get the best synthesize way.The best synthesize way to produce assemble dimer acid- adipic acid-neopentylglycol ester was alcohol acid ratio1.24:1, reaction time 8h, the highest reaction temperature 220℃, 0.12% dibutyltin dilaurate. The best synthesize way to produce assemble dimer acid- adipic acid-1,4- butanediol ester was alcohol acid ratio1.22:1, reaction time 7h, the highest reaction temperature 220℃, 0.16% dibutyltin dilaurate. The results of infrared spectrum and nuclear magnetic resonance showed that there were lots of hydroxy groups and ester bonds exist in both of the productions.Determine the synthesizeed method of the thermoplastic polyurethane elastomer .Build up the way to measure the mechanical property, water resisting property, hydrolysis resisting property, chemical medicine resisting property.Test the mechanical property, water resisting property, hydrolysis resisting property, chemical medicine resisting property of the thermoplastic polyurethane elastomer synthesized in the experiment,and compared with polycaprolacton, PTMEG, polyethylene adipate,polytetramethylene adipate thermoplastic polyurethane polyester.The results showed that, there were no streching sclerotic appearance under the 300% stretching modulus when the thermoplastic polyurethane polyester contains dimer acid.The breaking strength of assemble dimer acid- adipic acid-neopentyl glycol ester and assemble dimer acid- adipic acid-1,4- butanediol ester were 92% and 88%, 88% and 83%, 80 and 72%, 83% and 79%, after diping in bioling water, 1mol/L H2SO4, 1.25 mol/L NaOH, and methanol for 14 days.The percent of quality loss were 8% and 10% after diping in methanol for 14 days.All of the indexes were better than polycaprolacton, PTMEG, polyethylene adipate , polytetramethylene adipate thermoplastic polyurethane polyester. The dimer acid had a strong hydrophobicity because of the special long chain construction.Thermoplastic polyurethane polyester which had dimer acid can protect eater bond and resist the environment very well, so that the production have a more extending using area and a longer service life.