Study Of Decarboxylation Type Temporary Water Soluble Monomer-Decarboxylation Type Monomer Preparation And Its Performance Study

The monomer of decarboxylated water soluble paint given priority to with sulfonyl structure was ignited decarboxylation off under high temperature to change its solubility in water and solve the problem of poor water resistance of water-based coatings.In this paper, the monomer of decarboxylated water soluble paint was synthetized by two step reaction. In the first reaction, allyl sulfonium acetic acid was prepared with thioglycolic acid used as a raw material, tetraethylene glycol used as phase transfer catalyst and sodium hydroxide used to adjust p H. In the second reaction, allyl sulfone acetic acid was prepared with allyl sulfonium acetic acid used as a raw material, water used as a solvent and Oxone used as oxidant.Allyl sulfonium acetic acid was prepared by phase transfer catalytic method, and analyzed quantificationally by anoion chromatograph. The reactant ratio, catalyst dosage, temperature and p H were studied on the influence of allyl chloride conversion rate. According to the single factor experiment, the optimum reaction conditions were determined: the mole ratio of thioglycolic acid and allyl chloride was 1.6, the mole ratio of sodium hydroxide and allyl chloride was 3.4, the mole ratio of tetraethylene glycol and allyl chloride was 0.135,the temperature was 110 ℃,the reaction time was 1.5h.Under this condition, conversion rate of allyl chloride was 80.25%.The chemical structure of allyl sulfonium acetic acid was analyzed by 1H-NMR,mass spectrum and FT-IR, and verified that the composite was allyl sulfonium acetic acid. Three groups of experiments were arranged with uniform design method, the single factor experiment and orthogonal experiment method by four kinds of solvent to choose a group of developing solvent(benzene: isopropyl: methylene chloride: cyclohexane =1: 4: 4: 8)which could separate the allyl sulfonium acetic acid.Allyl sulfone acetic acid was prepared by oxone,and analyzed quantificationally by ultraviolet spectroscopy.The reactant ratio, temperature and time were studied on the influence of conversion rate of allyl sulfonium acetic acid. According to the single factor experiment, the optimum reaction conditions were determined: the mole ratio of oxone and allyl sulfone acetic acid was 3.2, the temperature was 100 ℃, the reaction time was 3.5h.Under this condition, conversion rate of allyl chloride was 86.58%. The chemical structure of allyl sulfone acetic acid was analyzed by 1H-NMR、FT-IR and mass spectrum, and verified that the composite was allyl sulfone acetic acid.