Novel waterproof agent for building gypsum, and preparation method thereof

Abstract

The invention relates to a preparation method of a novel waterproof agent for building gypsum. The method adopts methyl methacrylate, butyl acrylate and acrylic acid as raw materials and vinyltriethoxysilane as a coupling agent, and vinyltriethoxysilane is added to promote the formation of an organosilicon waterproof agent silicone resin network and form a coordination network-shaped film formed by organic molecule adsorption metal ions on a contact surface, so the combination ability with the surface of gypsum is enhanced, and the waterproof performance of the waterproof agent is further enhanced. The waterproof agent for building gypsum prepared in the invention has the advantages of small mixing amount in the use process, no unfavorable influences on the strength of gypsum, substantial improvement of the softening coefficient of gypsum products, reduction of the water absorption rate of gypsum, good waterproof effect and easy storage, and is an ideal novel waterproof agent for building gypsum.

Description

technical field [0001] The invention belongs to the technical field of preparation of waterproofing agents for building materials, and in particular relates to a novel waterproofing agent for building gypsum and a preparation method thereof. Background technique [0002] Gypsum is a kind of abundant resources. Gypsum products have good fireproof and sound insulation properties, and have good thermal insulation and humidity control functions. They are widely used in the construction industry. However, due to the poor waterproofness of gypsum products, the strength after water absorption is high The magnitude is reduced, and its development and use have been greatly restricted in modern times. At present, in order to solve the problems of poor water resistance such as low strength and easy warping and deformation of gypsum products after being exposed to moisture, the following three measures are usually adopted: one is to coat or impregnate hydrophobic substances or paint wat...

AI Technical Summary

Problems solved by technology

The first method is simple and easy to implement. If it can be strictly operated, it can achieve a relatively ideal waterproof effect. However, once the coated surface or local defects appear, the exposed gypsum will be eroded by water or even peeled off when it encounters water, resulting in The waterproof performance is reduced; the second method is that the hydration reaction between the gypsum and the active mixed material produces hydration products such as calcium sulfoaluminate hydrate. Although the water resistance is improved, due to the addition of pozzolanic materials, the block The whiteness of the gypsum block is reduced, affecting its decorative effect, and it is easy to cause cracking of the block in the later stage; the third method can not only maintain the decorative effect of the gypsum block, but also achieve the purpose of waterproofing

[0003] However, although traditional building gypsum waterproofing agents such as paraffin wax emulsion and styrene-acrylic emulsion can improve the waterproof performance of gypsum, the large amount added during use will have an adverse effect on the strength of gypsum, while silicone building waterproofing agents have a negative impact on the strength of gypsum. The influence of the strength of gypsum is small, but the relatively cheap methyl silicon alkoxide in the silicone-based waterproofing agent is largely soluble in water, and its binding ability with the substrate is not strong, so it is easy to lose with the large amount of water in the production process of gypsum products. And then cause its decline in improving the waterproof performance of gypsum

Therefore, the existing waterproofing agent for building gypsum has the defects of large amount of admixture during use, great influence on gypsum strength, and poor waterproof performance.