| Nowadays,because of some inferior coatings and adhesives used in the interior decoration process,these materials contain a large number of organic compounds,formaldehyde is one of the pollutants,which will cause indoor environmental pollution.Considering that formaldehyde is widely used in industry,the pollution scope of formaldehyde is wider.At present,there are few research methods for formaldehyde removal,among which physical method is the most widely used method.In our work,the chemical reaction method is adopted to purify indoor formaldehyde.In this paper,acrylate emulsion was synthesized by the polymer emulsion method.The emulsion type was used instead of the solvent coating,and applied to the interior wall coating.In addition,the functional monomer acrylamide is introduced into the synthetic emulsion,which can remove formaldehyde and replace solvent coating due to the special functional groups of functional monomers can make emulsion react with formaldehyde.The acrylate emulsion was synthesized by pre-emulsification and semi-continuous drop method.In addition,functional monomers were added in the synthesis process to make the emulsion have the function of removing formaldehyde.The process of semi-continuous pre-emulsifying drop addition was investigated by analyzing the IR spectrum,glass transition temperature,particle size analysis,rheology and the effect of removing formaldehyde from emulsion,thus the type of emulsifier,themixing time and speed,the monomer drop acceleration rate and the pre-emulsification temperature were determined.What's more,the optimum dosage of monomer,emulsifier and initiator,reaction temperature and reaction time and other technological conditions in polymerization process were also obtained.The effects of the amount of functional monomer acrylamide on the stability of emulsion polymerization,the viscosity of emulsion,the gel rate,the effect of purifying formaldehyde,the particle size of emulsion,and the water resistance of emulsion after film formation were systematically investigated.Finally,the key parameters of the whole process were obtained.The stirring speed of pre-emulsification was 500 RPM,the emulsifier was the mixture of RS-710 in proportion of 1:2,the pre-emulsifying temperature of 35 ?,the monomer dropping time was in the range of 40~50 min.After dripping,stirring for another hour,the seed reaction temperature was 80 ?,the polymerization reaction temperature was 78 ?,the pre-emulsion dropping time was in the range of 3~4 h,the stirring rate was 400 RPM,the heat preservation time was 1 h.After neutralization,the pH was in the range of 7~8.According to our data,we found that when the dosage of AM was 8%,the emulsion had the best performance,and the purification rate of formaldehyde was as high as 61.3%.The acrylate coatings with formaldehyde purification function were prepared with self-made acrylate emulsion and activated shell powder as base material and filler,respectively.The performance of self-made interior wall coating was analyzed by the effect of mixing time on material fineness,the effect of storage time on coating viscosity and the effect of paint on formaldehyde purification.According to our data,we obtain the coating formula,self-made emulsion was 73%,activated shell powder was 22%,dispersant was 1.5%,defoamer was 1%,glycerol was1.5% and leveling agent was 1%.The interior wall coating prepared under this formula has excellent performance and stability,and can meet the construction conditions.Therefore,It is a better environmental protection coating. |
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