| With the rapid development of the construction industry, people's demand for new building materials is also increasing day by day. Due to the increase of people's awareness of environmental protection and the continuous improvement of construction efficiency, gelatinous material gypsum products have been rapidly developed. At present, the most common gypsum products plaster, bond plaster, plaster, tile binder. Plaster plaster is a good quality of the internal wall and roof plastering materials, with its wall is delicate and smooth, not off powder and base bonding firm, no cracking off phenomenon, and fire prevention function; Bond gypsum is a new type of construction light board binder, is based on gypsum, add a variety of force mouth agent and made of adhesive body material, it is applicable to all kinds of inorganic building wall materials between the bond, with non-toxic, tasteless, early strong and fast coagulation, bonding and other characteristics, is building board, block construction materials; Gypsum caulking agent is the caulking material of the gap between gypsum plates and the repair of wall and cracks. These gypsum products have a series of different functions. In addition to gypsum and related fillers, the key problem is that cellulose ether additive plays a leading role. Because gesso cent does not have the cent of water gesso and half water gesso, different gesso is different to the property effect of the product, so thicken, protect water, delay setting decides the quality of gesso building materials. The common problem of these materials is hollow drum cracking, the initial strength is not up to, to solve this problem, is to choose the model of cellulose and retarding agent compound use method, in this regard, generally choose methyl or hydroxypropyl methyl 30000--60000, the amount of 1.5%-- 2%, cellulose focus is to play a role in water retention retarding lubrication. However, relying on cellulose ether as a retarder is not achieved here, citric acid retarder must also be added to the mix after use will not affect the initial strength. Water retention rate is generally in the absence of external water absorption, the amount of water natural loss, if the wall is large dry, base surface water absorption and natural evaporation make the material water loss too fast, the same empty drum, cracking phenomenon. This method of use is for dry powder mixing, if the preparation of solution can refer to the preparation method of solution. |
