Preparation And Properties Research Of Foaming Plaster Light-weight Wall Materials

This paper mainly studied the preparation, modification of the foaming plaster materials and its application on light partition board. Firstly, the X-ray diffraction analysis (XRD), chemical composition analysis and other test analysis means were used to analysis the main components of the raw materials. Then, the bubble pore structure of foaming plaster materials was introduced by physical foaming method, and the foaming plaster materials were modified by the different modified components. The scanning electron microscope (SEM) and other tests analysis means were used for discussing the modification mechanism. Finally, the fiber reinforced foaming plaster light inner partition boards were prepared and tested. The main contents can be divided into the following several parts:1. Several commercial foaming agents were used for preparing plaster foaming materials respectively, the effect of different foaming agents on foaming plaster were compared and analyzed. It has been found that the plant foaming agent was better to prepare plaster foaming materials compared with the sulphosalts foaming agent and the animal foaming agent for the performance such as good foaming multiple of18.7, so the plant foaming agent was chosen for the better foaming ability and preferably bubble size guaranteed the better performance of the plaster foaming materials. The poor setting time of plaster can be improved by adding retarder to meet the request of preparing foaming plaster, the retarding effect of the four kinds of retarders on plaster were investigated. It shows that the plaster’initial setting time was delayed from5minutes to31minutes with0.2wt%gelatin, and gelatin had less negative effects on the plaster materials’strength compared with other retarders. So the gelatin was chosen as the retarder in this topic.2. The influence of adding different proportion foams to plaster materials’properties were researched, foam stabilizer was added to improve the stability and structure of the bubbles. It has been found that the adding foams brought a large number of uniform dispersion of porosity into the internal structure of plaster sample. The porosity structure reduced the apparent density and coefficient of thermal conductivity of samples, improved the heat preservation and lightweight performance of the materials. Tests showed that adding0.8wt%foam stabilizer can reduce the defoamed ratio of foam by18%, increase the number of the closed bubbles and make the bubbles’size more evenly compared with the blank sample; The optimum dosage of the adding foam was100g powders mixed with150ml foams for preparing foaming plaster, under this optimum conditions, foaming plasters’ density and coefficient of heat conductivity achieved a better value, and compared to the blank plaster sample, the apparent density of the sample decreased from1205kg/m3to517kg/m3, the coefficient of thermal conductivity reduced from0.217W/(m·K) to0.121W/(m·K). The mechanical properties and water resistance of the sample were relatively good, still can satisfy the requirements for preparing foaming plaster materials.3. The foaming plaster material was modified in order to solve the problem of its own low hardness and poor water resistance by adding modified components such as fly ash, cement and composite waterproofing agent, the influence and mechanism of the modifying research were discussed. It has been found that adding fly-ash can improve the workability of plaster slurry, the strength and the water resistance performance can be modified by adding cement and composite waterproofing agent. The optimum modification scheme was mixed15wt%cement,20wt%fly ash, and6wt%composite waterproofing agent within the inorganic powder. The foaming plaster sample’water demand for normal consistency was44%, the flexural strength was1.98MPa, the compressive strength was3.90MPa, the water absorption rate was18.6%, and the softening coefficient was0.67after the modification. Compared with the unmodified sample, the foaming plaster sample’water demand for normal consistency was reduced by5%, the bending strength was increased by44.5%, the compressive strength was increased by38.3%, the water absorption rate was reduced by58.6%, and softening coefficient was increased by45.7%.4. The polypropylene fibers were added into the inorganic powder to enhance the bending anti-cracking performance of foaming plaster materials, and the fiber reinforced foaming plaster lightweight insulation inside wall plank was prepared. The result showed that the adding fiber had improved the bending anti-cracking performance of the foaming plaster materials. When the adding fibers’length were10-16mm and the mixing dosage were1.0wt%with the after-mixed method, the bending strength was increased by55.9%, the compressive strength was increased by18.1%, compared with blank simple, the other performances also can satisfy the requirements of preparing foaming plaster insulation inner partition wall materials. Further research were concentrated on the production process and application technology of the fiber reinforced foaming plaster lightweight insulation inner wall plank, the performance of the foaming plaster lightweight insulation inner wall plank can not only meet the requirements of the national’s corresponding standards but also has better properties of lightweight, heat preservation and sound insulation than other partition boards.