Study On Synthesis Of Novel Rosin-based Polyether Polyol And Rigid Polyurethane Foam

In this paper, this thesis focuses on friendly environment rigid polyurethane foam based on biomass resource rosin as material to synthesize novel rosin-based polyether polyol with formaldehyde, propylene epoxide and ethylene epoxide for the sake of protecting our environment and saving resources. This study has not reported before.The prins addition reaction between rosin resin acids and formaldehyde catalyzed by p-toluenesulfonic acid was studied in detail. The affecting factors of hydroxymethylation were studied by single and orthogonal experiments, the optimal technology was followed: amount of catalyst p-toluenesulfonic acid 0.8 %, reaction temperature 100℃, reaction time 6 h, molar ratio of formaldehyde to rosin 3:1. The hydroxyl value of product was 236 mg .g-1, percent conversion of material 80.56 %.The obtained product was characterized by spectrum methods, e.g FT?IR, 1H NMR, GC?MS. Finally, the mechanism of reaction was preliminary discussed.The novel rosin-based polyether polyol was synthesized by initiator hydroxymethyl rosin resin acids (40~100 % by weight of the initiator ), propanetriol with propylene epoxide and ethylene epoxide in the presence of alkaline catalyst by block condensation polymerization reaction. Further, the transparent liquid which were from the brown to yellow were attained after purification. The properties of polyether polyols with different hydroxymethyl rosin content or differernt epoxide based on the same initiator were studied, their viscosity and hydroxyl value were satisfied for rigid polyurethene foam. The optimum technology condition was obtained in block condensation polymerization reaction: amount of catalyst KOH 0.5 %; type of polymerization was in groups, first introducing into propylene epoxide, then ethylene epoxide; polymeric temperature 110~115℃, polymeric pressure 0.40 MPa; refined condition of polyether polyol, water 3.8 %, H3PO4 0.7 %, accessory ingredient 0.1 %; vacuumize temperature 100~110℃, vacuumize pressure 1.3 KPa. The structure of novle rosin-based polyether polyols were analyzed by FT-IR, TGA etc, finally.The rigid polyurethane foam which has good propeties was prepared by using polyols, isocyanate, vesicant (H2O, F-141b), surfactant, catalyst and other assistants in one step method. The novel rosin-based polyether polyols with different hydroxymethyl rosin strctures were used for preparing foams. The reaction activities of different polyols, affecting to heat resistance of foams of different [NCO]/ [OH] were studied and the foams were analyzed by using FT-IR, TGA, SEM, thermal decomposition kinetics methods. It was found that the addition of rosin ring and multi-hydroxymethyl structure could increase reaction activity of polyol, thermal stability, compression strength, activivation energy of pyrolysis. The relationship between structure and properties of polyurethane foam based on novel rosin-based polyether polyol was investigated. The purpose of present study was to provide favorable theoretical basis for application.