Preparation And Performance On The Diatom Styrene-acrylic Internal Wall Coating

As people living standard improved and the continuous development of building materials industry,people have higher requirement for interior wall decoration materials. Therefore, interior decoration materials is developing toward health, environmental protection, comfort, beauty and so on.Due to its porous structure, diatomite has strong adsorption force and great adsorption capacity.It is a kind of natural damping material. The interior decoration materials producted with diatomite wouldn’t emit harmful chemical substances to the human body and has the advantages of automatic regulating humidity and improving the living environment.And the damping interior wall material could avoid the damage to people health, the ecological environment caused by the air conditioner and air humidifier.This thesis mainly prepares a kind of diatom styrene-acrylic internal wall coating with diatomite as the main filler,adding titanium dioxide,kaolin and other fillers,and adding dispersant, wetting agent, flow ping agent, defoaming agent, thickener and film- forming agent, fungicide as additives,with ethylene glycol as solvent,and with the styrene acrylic emulsion as film forming material.This paper mainly investigated absorption and desorption characteristics of the diatomite.And the influence of different particle size of diatomite, adding different proportions of diatomite, the thickness of film on the absorption and desorption characteristics of the coating.And the absorption and desorption characteristics of the modification of inorganic salt and calcining process of diatomite and diatom styrene-acrylic internal wall coating was studied.And the different treatments of diatomite specific surface area test and SEM photos was tested.The basic performance of diatom styrene-acrylic internal wall coating with different processing diatomite was tested such as coating apparent,scrub resistance,impact resistance, flexibility, alkali resistance and so on.Experimental results show that the smaller the particle size of diatomite is more purity,and the absorption and desorption characteristics of diatomite and diatom styrene-acrylic internal wall coating is better.And when the rate of diatomite of total packing is 60% and the coating thickness is 0.25 mm,the absorption and desorption characteristics of the coating is the best.Calcination cannot purified diatomite used in this experiment.Due to this kind of diatomite is pure,the higher the calcination temperature, diatomite microporous structure is damaged more serious.Therefore the absorption and desorption characteristics of calcined diatomite as well as the diatoms of styrene-acrylic internal wall coating were reduced with the increase of calcination temperature.And calcium chloride modified diatomite can greatly improve the absorption characteristic of diatomite,but can’t improve the desorption characteristic.And the performance of the coating apparent and the basic performance is poor.Conclusions, the best ratio of internal wall coating for diatom:19% at 200~300 mesh diatomaceous earth,5% titanium dioxide, calcined kaolin, talc powder 3%, 2% calcium carbonate, 8% of styrene acrylic emulsion, 4% assistants, 2% hydroxyethyl cellulose, 54% water. Diatom medium wall paint the scheme made the hygroscopic good performance, scrub resistance, alkali resistance, impact resistance, flexibility, coating apparent etc.