Synthesis And Properties Of Two Kinds Of Reactive Surfactants

Conventional surfactants have brought excellent performance in emulsion polymerization,simultaneously,its emulsion always suffers from the problem of unstability.And the water absorption of latex film is poor,the latex film exhibit poor corrosion resistance and the latex film is easy to have pinholes.To work around this problem,reactive surfactants with reactive groups have caused people's attention.In this paper,a series of amphoteric reactive surfactants and a series of cationic reactive surfactants had been synthesized?hereinafter referred to as M_n and D_n?.The surface chemical properties and the application performance of two series of reactive surfactants had been comprehensively studied.The main contents and results are as follows:Three reactive amphoteric surfactants?M10,M12 and M14?with different alkyl chain lengths had been synthesized using N,N'-Dimethyl-1,3-propyldiamine,maleic anhydride and alkyl bromide?CH₃?CH₂?_nBr,n=9,11,13?as raw materials.The reaction conditions of acylation,neutralization and quaternary ammoniation were discussed by single factor,and the bestsynthesisconditionswereobtained.Acylationreaction:whenn?N,N-dimethyl-1,3-propane diamine?=0.10,n?N,N-dimethyl-1,3-propane diamine?:n?maleic anhydride?=1:1,the mixtures of maleic anhydride and 100 mL benzene were dropped into the solution of cis-butenedioic anhydride and 100 m L benzene,and the mixtures were dropped at30?during 1 h.After dropping,the temperature of the reaction was risen to 50?,and the reaction was kept for 2 h.The yield of the intermediate maleic acid could reach to 89.2%.Neutralization and quaternary ammoniation:pH was around 8 during the reaction of neutralization,n?maleic acid?:n?alkyl bromide?=1:1.1,the volume ratio of isopropanol and water was 2:1,the time of reaction at reflux temperaturethe was 10 h,and the yield of M10,M12 and M14 were 88.5%,86.7%and 85.9%,respectively.The compounds had been characterized by IR,MS,¹H NMR.The Krafft points of M10,M12 and M14 were 13.5,15.6,18.3?,respectively.The critical micelle concentration?cmc?and the corresponding surface tension(?_cmc)of M10,M12 and M14 were measured at temperature range from 298 to 313K.The results showed that the cmc of M10,M12 and M14 were 5.89×10^-4 mol·L^-1,2.63×10^-4mol·L^-1 and 1.35×10^-4 mol·L^-1,the?_cmc of M10,M12 and M14 were 31.26 mN·m^-1,28.79mN·m^-1,26.87 mN·m^-1 and the degree of counterion binding?K₀?of M10,M12 and M14were 0.4248,0.4169,0.4162 at 298 K,respectively.As the temperature rising,the cmc increased gradually,but the?_cmc and K₀ decreased moderately.With the increase of hydrophobic chain length,the foaming property,emulsifying property and wettability of M_n got better,and the properties of M14 were better than those of M12 and M10.A series of cationic reactive surfactants?D6,D8,D10,D12?had been designed and synthesized using 2-?Dimethylamino?ethyl methacrylate?DM?and dibromo alkane?Br?CH₂?_nBr,n=6,8,10,12?as raw materials.In the experimental process,n?DM?:n?Br?CH₂?_n Br?=2.1:1,the reaction solvent was acetone and the time of reaction at reflux temperaturethe was 8 h.The yields of D6,D8,D10 and D12 were 85.9%,87.8%,88.9%and89.6%,respectively.The compounds had been characterized by MS,¹H NMR.The Krafft points of D6,D8,D10,D12 were all below 0?.The cmc of D6,D8,D10,D12 were2.24×10^-3 mol·L^-1,1.45×10^-3 mol·L^-1,1.09×10^-3 mol·L^-1,5.50×10^-4 mol·L^-1,the?_cmc of D6,D8,D10,D12 were 50.53 mN·m^-1,45.75 mN·m^-1,44.14 mN·m^-1,43.13 mN·m^-1 and the degree of counterion binding?K₀?of D6,D8,D10,D12 were 0.4248,0.4169,0.4162 at 298 K,respectively.Among the surfactants of D series,the bactericidal effect of D12 was better,especially for the low concentration of enterococcus haystellus and staphylococcus aureus,which could make the bactericidal effect up to 99.99%,and D12 could also show a very good bacteriostasis effect to escherichia coli.With the increase of chain length,the antistatic property and fabric softness of the surfactants of D series were all improved.Among the synthetic surfactants,the emulsifying effect of M14 on methyl methacrylate and butyl acrylate was the best.M14 was chosen as the object of emulsion polymerization experiment.For determining the best emulsification process,the gel rate and latex absorbability of emulsion polymerization were investigated by single factor experiments.The results shown that the dosage of initiating agent was contributed to 0.5%of the total mass of monomer,the dosage of emulsifier was contributed to 4%of the total mass of monomer and w?MMA?:w?BA?=60:40?wt%?.Meanwhile,the stability of the emulsion under the optimum emulsification process was tested.