Study On Synthesis And Performance Of Antibacterial Phosphorus-free Detergent Auxiliary P(AA-DMDAAC)

This paper explored the synthesis process of sodium polyacrylate with sodium hypophosphite as chain transfer agent.On this basis,determine the reactivity ratio of acrylic acid(AA)and dimethyldiene propylene ammonium chloride(DMDAAC)and the composition equation of the copolymer,they provide a theoretical basis for the synthesis of P(AA-DMDAAC),and then the structure of P(AA-DMDAAC)is designed,it is applied as a cleaning aid with antibacterial properties.The main tasks as follows:(1)Explore the synthesis route of sodium polyacrylate(PAANa)and its influencing factors in the synthesis process,and determine the best process of sodium polyacrylate synthesis:acrylic monomer mass percentage concentration is 35%;the amount of sodium hypophosphite is 1.060 g(dissolved with 54.25 g water);the amount of ammonium persulfate is 1.35 g(dissolved with 42.5 g water);the reaction temperature is 90℃;the rate of acrylic acid monomer drop acceleration is 0.374 mL/min;the rate of drop acceleration of ammonium persulfate solution is 0.531 mL/min;the holding time is 3 h.(2)By drawing the copolymer composition curve of AA-DMDAAC,it can be seen that the ratio of DMDAAC units in the copolymer is smaller than the ratio of DMDAAC monomers to the total monomers in the initial stage during the reaction,and it can be speculated that r(DMDAAc)<1,r(AA)>1,AA prefers self-polymerization,DMDAAC prefers copolymerization.Using the reactivity ratio between the two monomers[r(DMDAAC)= 0.42,r(AA)=5.11]and the copolymer composition equation(F1=0.42f12+f1f2/0.42f12+2f1f2+5.11f22)to design the molecular structure of P(DMDAAC-AA),and they provide theoretical guidance for the modification of the molecular structure of copolymer and the sodium polyacrylate of quaternary ammonium salt adjustment.(3)The molecular structure was designed to synthesize P(AA-DMDAAC)with uniform unit distribution and regular structure.When the molar ratio of AA/DMDAAC monomer is 24,the drop rate of acrylic acid is 0.374 mL/min;under this optimal process obtain copolymerization product performance:270.2 mg/g for calcium ion sequestration,192.0 mg/g for calcium carbonate dispersion,buffer reduction is 0.645 mL,relative scale inhibition performance for calcium carbonate is 67.5%,the minimum inhibitory concentration(MIC)of E.coli and Staphylococcus aureus is 2.56 mg/mL;when the molar ratio of AA/DMDAAC monomer is 24,the content of DMDAAC unit in the copolymerization product of the copolymerization product is F1=0.8%.