Lightweight plastering gypsum is a new environmentally friendly and energy-saving wall plastering material that replaces traditional cement mortar. It has been widely used with its many advantages. Recently, some customers have reported that when using lightweight plaster, the wall is moldy. This year, I will analyze the reasons and solutions for mildew on the light plaster.
The moldy phenomenon of gypsum-based products is mainly due to the unstable performance of gypsum powder, which has a great impact on the finished product. The finished plastering gypsum mortar will also have such problems. The moldy problem reported by customers above is one of them. One kind. Secondly, high humidity in the construction environment will also cause mildew in the later stage of the plastering plaster. The plastering mortar made of gypsum powder is not resistant to moisture and is suitable for leveling indoor dry areas. It is not suitable for outdoor, kitchen, and toilet. The construction environment has high humidity. Will absorb moisture and mold. If mildew occurs frequently, it is suitable to add an anti-mold agent.
Gypsum powder has more impurities;
The construction environment has high humidity;
Increase the anti-mold agent;
Lightweight plastering gypsum is mainly composed of gypsum powder, perlite (vitrified beads), cellulose, retarder, starch ether, etc.
Cementitious materials: The cementitious materials are mainly gypsum powder. Commonly used are desulfurized gypsum and phosphogypsum, which mainly provide strength and skeleton for mortar.
Retarder: Delay the hydration rate of gypsum, so that the mortar has an appropriate operating time. The commonly used gypsum retarders mainly include citric acid, tartaric acid and some proteins with large molecular weight.
Starch ether: improve the sag resistance of the mortar and improve the operation performance.