| Bronopol is a broad-spectrum fungicide bromo-nitro alcohols with high bactericidal activity and low concentration and also wide range of pH using ,it has no allergic stimulating with the human skin, and widely used in many cosmetics and cleaning products. For its high activity,wide range of products sterilization and low concentrations using, it was widely used in detergents, fabric treatment agents, pesticides fungicides, disinfectants, medicine, in addition to the cosmetics as the primarily preservatives , and it can be also used in the industrial water treatment agent when mixed with other preservatives . Its research and industrial production was promoted for the large demand in a variety of industries.In this paper,Bronopol was synthesized by hydroxymethylation and bromination using nitromethane, formaldehyde and bromine as raw materials ,water-ethanol as solvent in the presence of NaOH.The effects of solvent kinds, molar ratio of solvents, molar ratio of reactants, reaction temperature ,reaction time on the hydroxymethylation reaction results were examined. Under the synthesis conditions as follows:n(nitromethane):n(NaOH):n(formaldehyde)= 1:1:2, hydroxymethylation temperature 20℃, hydroxymethylation time 1.5h, using 34g mixture of m(ethanol):m(H2O)= 1:1 as solvent.Orthogona1 test was used to study the effects on bromination reaction result such as molar ratio of reactants, reaction temperature, reaction time. The obtained optimum reaction conditions were n(nitromethane):n(bromine)= 1:1, bromination temperature 15℃, bromination time 0.5h. Bronopol was refined by recrystallization after testing the solubility in solvent such as water,ethanol,propanol,butanone,ethyl acetate,chloroform and also the mixtures.Under the synthesis conditions as follows:ethanol-chloroform mixture of which mass ratio of ethanol to chloroform was 1:1.ethyl acetate-chloroform mixture of which mass ratio of ethyl acetate to chloroform was 1:1.Under above conditions, the yield of rush product was≥90%. After purified by recrystallization, the yield and purity of product were about 83% and≥99% respectively and the yield of NaBr were about 93%.The structure of obtained product was characterized by FT-IR, 1HNMR.Kathon which is a mixture composed by two active ingredients: Methyl 2 - isothiazolone ketone (MIT) and 5 - chloro -2 - methyl - isothiazolone ketone (CMIT) is a highly effective broad-spectrum suppression agents.Kathon has strong biological activity, both antibacterial and sterilization .it can be a solution to fungus infection fermentation products caused by mildew, deterioration, excessive bacteria and other issues.Additionally, for its penetration on mucus , it can be not only used in cosmetics, detergents, but also for industrial sterilization ring of water, machine tool coolant, paint, etc., it is extremely broadly used as a kind of environmental friendly "green products" fungicide and worth developing value.In this paper,Kathon was synthesized by three steps using methyl acrylate, sulfur , sodium sulfide, sodium bicarbonate, methylamine and sulfuryl chloride as raw material,water and 1,2-dichloroethane as solutions.The effects of molar ratio of solvents, reaction temperature ,holding temperature,holding time ,amount of NaSX reacted with excess sulfur,reflow temperature ,reflow time on the reaction dimethyl 3,3'-dithiobispropionate synthesized results were examined. The obtained optimum reaction conditions were n(MA):n(NaHCO3):n(Na2SO3):n(Na2SX)=1:1:0.4:0.5, reaction temperature 10-15℃,holding temperature 25℃,holding time 5h,1mol / L sodium dosage 80ml reflow temperature 60℃,reflow time 3h,150ml water as solution.The effects of molar ratio of reactants, reaction temperature ,holding temperature ,holding time on the reaction N,N'-Dimethyl-3,3'-dithiodipropionamide synthesized results were examined. The obtained optimum reaction conditions were n(dimethyl3,3'-dithiobispropionate ):n(methylamine )=1:2,reaction temperature 0-5℃,holding temperature 20-25℃,holding time 12h.Orthogona1 test was used to study the effects on the reaction synthsized Kathon result such as molar ratio of reactants, reaction temperature, reaction time and the effects of molar ratio of solvent,holding temperature ,holding time were also examined.The obtained optimum reaction conditions were :n(N,N'-Dimethyl-3,3'-dithiodipropionamide ):n(sulfuryl chloride )=1:4, reaction temperature 5-10℃,reaction time 30min,holding temperature 25℃,holding time 24h,80ml 1,2-dichloroethane as solution.Under above conditions, the yield of 3,3'-dithiobispropionate was≥86%. the yield of N,N'-Dimethyl-3,3'-dithiodipropionamide was about 89%,the yield of Kathon was about 82%.The structure of obtained product was characterized by FT-IR, 1HNMR .
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