Study On Preparation And Performance Of Multifunctional Composite Antifoam Agent

With the aggravation of the energy crisis and the increasing importance of environmental protection,the development of environmentally friendly multi-functional industrial additives is of great significance.In the metal processing industry,processing additives are expected to have the functions of defoaming,rust prevention and lubrication,in order to reduce dosage,save resources and reduce environmental pollution.In this study,polyether ester defoaming agent was synthesized according to the requirement of enterprises.On this basis,the compound defoaming agent with anti-rust and lubricating functions is developed by adding water-based additives with anti-rust and lubricating functions,so that it not only has good defoaming effect,but also has good anti-rust and lubricity,in order to meet the requirements of modern processing and green manufacturing.In this study,polyether ester defoamer was synthesized by acid catalysis esterification with propylene glycol block polyether L62 and stearic acid as raw materials and p-toluenesulfonic acid as catalyst.The optimum reaction conditions were obtained by optimization: the reaction temperature was 190?,the reaction time was 6 h,the molar ratio of polyether and stearic acid was 1:2,and the catalyst dosage accounted for 0.5% of the total molar fraction of the raw material.An aqueous solution of sodium dodecyl benzene sulfonate was used as a foaming liquid,and the defoaming performance of the polyether ester was investigated.It was found that its foam suppression efficiency and defoaming efficiency were both 100%,and it had a certain resistance to hard water.The structure of the product was determined by infrared characterization.Five organic carboxylic acid triethanolamine salts were selected as antirust components and compounded with polyether ester defoaming agent to obtain multifunctional compound defoaming agent.By examining the rust-preventive properties and defoaming properties of the product,it was found that the mass ratio of triethanolamine(6,6',6''-(1,3,5-triazine-2,4,6-triyltriimino)tris-Hexanoic acid)triethanolamine salt and ricinoleic acid triethanolamine salt was 1:2 as a composite antirust component,the multifunctional composite defoamer prepared under the condition that the mass ratio of polyether ester and composite antirust agent is 2:1 has good defoaming and antirust properties.Through the investigation of the lubrication performance of the compound defoaming agent,it is found that the product can significantly improve the carrying capacity of water,showing good extreme pressure,anti-wear and anti-friction characteristics and lubrication stability.As synthetic material of compound defoaming agent,propylene glycol block polyether's viscosity property is the experimental basis for further improving the lubrication performance of the product.The kinematic viscosity of six different molecular weight of propylene glycol block polyethers in the temperature range of 298.15?368.15 K was measured.It was found that at the same temperature,the higher the molecular weight,the higher the kinematic viscosity.Kedzierski index model was used to fit the measured data of kinematic viscosity with the temperature,and the model parameters were determined.The model can correlate the viscosity and temperature of propylene glycol block polyether well.On this basis,the fourth order polynomial is used to fit the model parameter value and the molecular weight,and the correlation equation of molecular weight and the exponential model parameter is obtained.The viscosity of propylene glycol block polyether at different temperatures can be estimated,which provides basic data for its further application.