Chemical Additives For Foamed Cement Heat Preservation Material Preparation And Performance Improvement

At present,the market of wall insulation material consists of two categories:organic and inorganic,and the former must withdraw from the external walls of the insulation market due to the combustion of organic materials can not reach A-level.Compared with traditional insulation materials,cement foam insulation material is a kind of new wall insulation material with broad application foreground for it has advantages of highstrength and lightweight,heat insulation,fireproof capability and environmental protection.The basic formulas of foaming cement in this paper are: ordinary Portland cement(42.5),fast hard sulfide aluminate cement(42.5),water,calcium stearate,formaldehyde(analytical pure),hydrogen peroxide(analytical pure).Additives: triethanolamine,calcium chloride,aluminum sulfate,sodium carbonate,sodium rosin,methyl cellulose ether,etc.By single factor experiment,the basic formula of each component,the quantity of additives,mixing time,hydration,the temperature of the water,steamed keep time and temperature was investigated,the influence factors,such as pipe and optimized by the orthogonal experiment of foamed cement formula.The optimal formula is: general silica cement: 200 g;Sulfur aluminum cement: 13 g;Calcium stearate: 3 g;Water: 108 ml;Formaldehyde: 8 ml;Hydrogen peroxide: 17 ml.Stirring time: 3 min;Pipe temperature: 90 ℃;steam curing time:6 h;curing time:7 day.Suitable additives:triethanolamine:0.1g;calcium chloride:2 g;aluminum sulfate:5 g;sodium carbonate:0.6 g;rosin acid sodium:0.2 g;methyl cellulose ether:0.07 g.The foaming cement obtained in this way has good strength,low thermal conductivity and low bulk density.Examines the stirring time,water temperature,steaming time influence on foaming,determine the optimum process conditions of preparation of foamed cement: total mixing time 3 min,water temperature 18 ℃,steaming time 6 h.