Room-temperature moisture cured one-component water-expansion polyurethane sealant

Abstract

The invention discloses a room-temperature moisture cured one-component water-expansion polyurethane sealant which is paste and comprises the following raw materials in parts by weight: 30-50 parts of liquid polyether polyurethane prepolymer base material, 10-25 parts of plasticizer, 0.5-1 part of a coupling agent, 10-30 parts of super water absorbent resin, 10-30 parts of other fillers, 0.01-0.05 part of catalyst and 0.2-3 parts of adjuvant. The preparation method of the sealant comprises the following steps: 1. placing di-functionality polyether glycol and tri-functionality polyether glycol in a container according to a weight ratio, stirring and dehydrating by a vacuum pump, and then adding polyisocyanate and the catalyst under stirring to obtain the liquid polyether polyurethane prepolymer base material for later use; 2. adding the plasticizer and the coupling agent to the liquid polyether polyurethane prepolymer base material to obtain a mixture; and 3. adding the super water absorbent resin and other fillers to the mixture, then adding the catalyst and the adjuvant, evenly dispersing into paste, and then packing the paste into a packaging substance for sealing. The sealant of the invention has good adhesive property on a sealed surface, and the paste is cured under a moisture condition, thus achieving the purpose of avoiding leakage.

Description

technical field [0001] The invention relates to a sealant, which is a room-temperature moisture-cured single-component water-swellable polyurethane sealant mainly used for leak prevention and plugging in construction projects. Background technique [0002] In the construction of construction projects, tunnels, subways and sewage treatment tanks, etc., it is often necessary to carry out anti-seepage treatment at construction gaps and deformation gaps. Water-swellable rubber is widely used in this field to prevent leakage and has a better waterproof effect. It is a preformed rubber strip shape, cut into the required shape and size according to needs, and embedded in the part that needs waterproof sealing . During the use, it was found that this kind of sealing strip has many shortcomings: the strip has no adhesive force with the surface to be sealed, the position of the strip is easy to change during the construction process, and it is difficult to make a good seal when the s...

AI Technical Summary

Problems solved by technology

During the use, it was found that this kind of sealing strip has many shortcomings: the strip has no adhesive force with the surface to be sealed, the position of the strip is easy to change during the construction process, and it is difficult to make a good seal when the strip absorbs water and expands. Filling gaps can sometimes seriously affect the waterproof effect; the construction is complicated and needs to be processed after construction; because the artificial embedding of the rubber strip takes a long time and requires a more skilled operation level, when the embedding quality is poor, it cannot be waterproof. effect

To address these deficiencies, those skilled in the art have improved the raw materials of the sealing strips. Although the elasticity has been increased, the above deficiencies still cannot be better solved.