Method for reinforcing alpha hemihydrate gypsum hydrated hardenite by employing organic complex additive agent

Abstract

The invention discloses a method which adopts an organic compound additive to reinforce an alpha-semi-hydrated gypsum hydration hardened body. Calculated by the total mass of alpha-semi-hydrated gypsum and an additive, the additive is prepared according to the following percentage by mass: 0.01 to 3.0 percent of high efficient naphthalene water reducing agent (FDN), 0.01 to 3.0 percent of high efficient melamine water reducing agent (SM), 0.01 to 3.0 percent of high efficient polycarboxylic acid water reducing agent (PC) and 0 to 1.3 percent of antifoaming agent. The additive and an alpha-semi-hydrated gypsum raw material or a powder grinding material undergo even dry mix and then are fully mixed with an amount of water inside mixing equipment; and mixed gypsum undergoes condensation and hardening according to product requirements. The 2h wet rupture strength of modified gypsum is increased by 20 to 60 percent, while 2h wet compressive strength is increased by 30 to 100 percent; meanwhile, the absolute dry rupture strength of the modified gypsum is increased by 35 to 70 percent, while the absolute dry compressive strength is increased by 30 to 100 percent; moreover, the method has appropriate condensation time, fine and clean appearance and excellent leveling property and water resistance.

Description

technical field [0001] The invention belongs to the technical field of application of inorganic materials, and specifically relates to an additive compound formula for improving the strength of α hemihydrate gypsum hydration hardened body with high-efficiency water reducer as the main component and its application method. Background technique [0002] Gypsum is a building material with a long history of application, and it is listed as the three pillars of inorganic cementitious materials together with lime and cement. It has the advantages of light weight, fast condensation, good fire resistance, low heat and sound transfer, efficient construction, and harmless to the human body. It is an energy-saving green material that is respected and developed internationally. The application of gypsum materials is usually through the hydration and hardening of hemihydrate gypsum to obtain dihydrate gypsum products. There are two forms of hemihydrate gypsum, α and β. Among them, α hem...

AI Technical Summary

Problems solved by technology

Compound modification can bring multiple effects or achieve superimposed effects, which is an important development direction of additive technology at present, but domestic related research is almost blank

[0004] Commonly used high-efficiency water reducers such as naphthalene series (FDN), melamine series (SM) and polycarboxylate series (PC) can achieve significant enhancement effects when used alone to modify cementitious materials, but at the same time it will also affect other properties. defect