Study On Preparation And Application Of Ammonium Salt-based Acrylate Cationic Poly Urethane Composite Emulsion

Cationic water-borne polyurethanes(CWPU)is one kind of aqueous polyurethanes that generally contains ammonium ions(Generally quaternary ammonium ions)or sulfonium ions in the main or side chains.At present,there are few researches on CWPU in science and industry fields.This study explored the application of CWPU in antimicrobial finishing of textiles,and modified it with castor oil(CO)and acrylate to reduce the use of petrochemical raw materials and improve the basic and antibacterial properties of CWPU.First,in this study,castor oil-based cationic aqueous polyurethane was successfully prepared by pre-polymer method.The effects of CO content,Nmethyldiethanolamine(MDEA)content and R value on CWPU performance were investigated by single factor experiments.The experimental results were analyzed by means of infrared spectroscopy,laser particle size analyzer,thermal analyzer,mechanical testing,scanning electron microscopy and antibacterial experiments.Through the analysis,with the increase of CO content,the average particle size of emulsion shows the trend of decreasing and then increasing,the tensile strength of CWPU latex film shows the trend of first decreasing and then increasing and then reducing,the thermal stability of the latex film has greatly improved,the water absorption of latex film decreased from 10.2% to 4.6%.The surface of fabrics treated with CWPU emulsion is smooth,and the concave grooves disappear.When the content of MDEA increased,the antibacterial activity of cotton fabric against Staphylococcus aureus and Escherichia coli shows the trend of significant increasing.When MDEA content was 8%,the antibacterial rates of the two kinds of bacteria were 77.3% and 82.2% respectively.Then,in this study,we designed and synthesized an ammonium salt-based acrylate monomer(ASA)with potential antibacterial properties by inverse synthetic analysis.The products of each step were characterized by means of NMR.The effects of solvent type,raw material ratio and catalyst equivalence on the yield of each step were investigated.Through analysis,intermediates P1,P2 and final product ASA were successfully synthesized,when the solvent is selected as absolute ethanol,the yield of P1 can reach 99%,when the molar ratio of raw materials was chosen to be 1: 1.8 and the alcohol equivalent of catalyst DMAP was 0.08,the yield of P2 could reach 76%.Finally,in this study,acrylate polyurethane composite emulsion(WPUA)was synthesized with ASA(Lab-made),methyl methacrylate,butyl acrylate,HEMA,IPDI,PBA and MDEA as the main raw materials.The effect of total acrylate(ACR)content and monomer ASA content on the comprehensive performance of WPUA.The experimental results were analyzed by means of infrared spectroscopy,laser particle size analyzer,thermal analyzer,mechanical testing,scanning electron microscopy and antibacterial experiments.Through the analysis,with the increase of ACR content,the average particle size of WPUA composite emulsion shows the trend of increasing,the tensile strength of WPUA latex film shows the trend of increasing and then decreasing,the water absorption of WPUA latex film shows the trend of decreasing and then increasing,when ACR content is 20%,the water absorption of latex film is 3.8%.With the increase of ASA content,the average particle size of WPUA composite emulsion shows the trend of decreasing and then increasing,the tensile strength of WPUA latex film shows the trend of increasing and then decreasing,the overall change is small.When the content of ASA increased,the antibacterial activity of cotton fabric against Staphylococcus aureus and Escherichia coli shows the trend of significant increasing.When ASA content was 4%,the antibacterial rates of the two kinds of bacteria were 92.1% and 95.4% respectively.