Preparation And Study Of The Heat Insulation Building Coating

Nowadays, Energy conservation and environmental protection are the pursuit goal ofis the scientists form all over the world, paraffin phase change material is applied widely, ithas many advantages, but at the same time, there are a lot of shortage, such as the volumeis big, the liquid leak and the heat transfer is bad when solid-liquid phase change. Themicroencapsulation of paraffin can be a very good solution to solve the above problems, anthat is the focus research in recent years. And it’s significant that the paraffin microcapsuleused in architectural coatings, this coatings will be effect of thermal insulation. It canabsorb solar radiation of heat, and keep indoor temperature without power consumption,In this paper, microencapsulated phase change material (PMC) was prepared by thein-situ polymerization method, using mix paraffin as core material and urea-formaldehydeprepolymer as shell material respectively. And then, compounding coating withmicroencapsulated.By analysis of Scanning Electronic Microscope and FT-IR, the surface configurationand the shell structure of the microcapsule were investigated. Differential scanningcalorimeter (DSC) was used to research the thermal properties of the microencapsulatedparaffin, phase-transition temperature and enthalpy of phase change. The results showedthat different paraffin was claded bypolyurea formaldehyde resin successful. By DSCanalysis, paraffin content of microcapsule, from large to small, are octadecanemicrocapsule, solid paraffin microcapsule, liquid paraffin: octadecane: solid paraffin is1:1:1, liquid paraffin: octadecane: solid paraffin is1:2:1microcapsule, maximum contentis37.2%, the phase transition enthalpy is124.0J/g which is the highest than others, thediameter is4μm, obviously less than others’diameter10μm. Paraffin microcapsulesurface is rough, the shape is globularity, it has agglomeration. Adding this4microcapsule above in the coatings. By the test of heat insulation, theresults show that the best heat insulation property is adding microcapsule whith theproportion of liquid paraffin, octadecane and solid paraffin is1:1:1, the largesttemperature difference is8.2℃, the average temperature of7.2℃. And when the qualityof diatomite and microcapsule are15.0g totally, the proportion of diatomite andmicrocapsule is7:8, the heat preservation function of the highest; When the amount ofmicrocapsule less than7.0g (the amount of diatomite is more than8.0g), with the amountof microcapsule increasing, the average temperature increased, the insulation abiltyincreased, When the microcapsule quantity more than7.0g (the amount of diatomite is lessthan8.0g), with the amount of microcapsule increasing, the average temperature decrease,insulation capacity weakened. At the same time, adding microcapsule and immersionparaffin diatomite’s coating’s heat preservation effect is better than only addingmicrocapsule or only adding immersion paraffin diatomite, maximum temperature13.2℃,the average temperature of11.8℃, these two kinds of materialtogether have synergy,enhanced the thermal insulation performance of the coating effectively. Through thecoating heat insulation performance, viscosity, coating drying time, acid resistance, alkaliresistance, adhesion and film basic performance test, the coating accord with nationalstandard.