Abstract:
Self-catalyzing polyol dispersions with tertiary amine groups (TBP or TDP) were prepared by reaction of terpinene-maleic ester based epoxy resin (TME) with N-benzylethanolamine (BEA) or diethanolamine (DEA). The tertiary amine groups in the polyol structure could catalyze the crosslinking reaction between hydroxyl group and isocyanate group in the crosslinking reaction of polyol dispersions and polyisocyanate to form two-component waterborne polyurethane. Suitable synthesis conditions were obtained by studying the effect factors of synthesis reaction. The optimum reaction conditions of the preparation of TME based polyols TBP or TDP were reaction at 80 ℃ for 1 h with using ethanol as solvent and the amount of ethanol was about 10% of the total quality of reactants. The chemical structures of the polyols were characterized by FT-IR and NMR and the average molecular weight of the polyoys was determined by GPC. The effect of neutralization degree on the particle size distribution of polyol dispersions was investigated by laser particle sizer. When the neutralization degree was 90%, the particle size distribution of polyol dispersions was multimodal and the stability of the dispersions was poor. However, when the neutralization degree was 100%, the particle size distribution of the dispersions was unimodal and achieved nanoscale dispersion.