Studies On Synthesis And Properties Of Waterborne Urethane Surfactants

Ten kinds of waterborne polyurethanes based on surfactants including three water-based non-ionic polyurethanes, three water-based anlonlc polyurethanes derived from maleic anhydride and four excellent water-based anlonlc polymerizable polyurethanes were synthesized by 2,4-toluene dissocyanate (TDI) and polyethylene glycols(PEG) of different molecular weight as feedstock , which are characterized by FT-IR and 1HNMR. The main results are as follow:First, three water-based non-ionic polyurethanes(B1 PEG800,B2 PEG1000 and B3PEG2000) were synthesized by 2,4-toluene dissocyanate (TDI),polyethylene glycols (PEG800,PEG1000 and PEG2000),maleic anhydride (MA) and trimethylolpropane (TMP) as feedstock , which are characterized by FT-IR and 1HNMR. The influential factors, such as the reaction temperature, reaction time, the amount of acetone were discussed. Their some characters,such as the CMC,clouding point and the surface tension were also studied.The results show that the optimum reaction conditions are with 35mL acetone / TDI / mol as solvent at 65℃for 4 h. The CMC of B1 PEG800 is 0.5 mol/L and its surface tension is 33 mN/m ; The CMC of B2 PEG1000 is 0.375mol/L and its surface tension is 38.85 mN/m at 25℃by maximum bubble pressure method . The solutions are Newtonian fluids. While the molecular weight increased, the clouding point of the surfactants would increase. The clouding point of B1PEG800 was 39.6℃, the clouding point of B2 PEG1000 was 51.9℃and the clouding point of B3PEG2000 was 58.9℃.Secondly, three water-based anlonlc polyurethanes derived from maleic anhydride(B0PEG400,B1 PEG800 and B2 PEG1000)were synthesized by polyethylene glycols (PEG400,PEG800 and PEG1000),2,4-toluene dissocyanate (TDI),maleic anhydride (MA) and triethylamine (TEA) as feedstock , which are characterized by FT-IR and 1HNMR. The results show that TDI should drop into PEG drop-by-drop; The best reaction temperature is of the order of 65℃; When the concentration of NaCl dropped into the liquor reaches 0.065mol/L , the liquor would became cloud . pH has a great effect on the reaction . When isocyanate reacts with hydroxy compound ,the acidic catalyzer would be dropped into it ,which could slower the rise of the chain and control the reactin of the cross bonding. The reaction needs 0.05% dibutyltin dilaurate stannum as catalyzer.Thirdly, a series of excellent water-based anlonlc polymerizable polyurethanes were obtained from polyethylene glycols (PEG) , 2,4-toluene dissocyanate (TDI),dimethlolpropionic acid (DMPA)as feedstock and triethylamine (TEA) as neutralizer, which are characterized by FT-IR and 1HNMR. The results show that isocyanate and maleic anhydride have already reacted absolutely. When the content of DMPA reaches 2.0%, the capability and the appearance are preferably . The content of COOH increases as well as the viscidity of the dispersoid. The appearance of the polyurethane is preferably and steady when triethylamine is made use of neutralizer and neutralizing reaches 90%～100% simultaneity. The micelle would come into being and the critical micelle concentration would minish when NaCl is dropped . The efficiency of the surface tension would increase while the concentration of NaCl increases.To the same series, surfacants with more carbon numbers show better emulsifying ability, surfactants with less carbon numbers show better foaming ability.Finally, three kinds of surfactants could reduce surface tension availably, but the surfacant of water-based non-ionic polyurethanes are more better than the other one.When the concentration is less than 0.475 mol/L ,the surfacant of water-based anlonlc polyurethanes derived from maleic anhydride are better than water-based anlonlc polymerizable polyurethanes; When the concentration is bigger than 0.500 mol/L, the surfacant of water-based anlonlc polymerizable polyurethanes are better than water-based anlonlc polyurethanes derived from maleic anhydride. The water-based anlonlc polymerizable polyurethanes show better emulsifying ability, while the water-based non-ionic polyurethanes show better foaming ability.