Interface agent for high-speed railway ballastless track polyurethane caulking material and preparation method thereof

Abstract

The invention relates to an interface agent for a high-speed railway ballastless track polyurethane caulking material and a preparation method thereof. The interface agent comprises the following raw materials in parts by weight: 100 parts of isocyanate prepolymers, 80-120 parts of solvents, 0.1-0.5 part of catalysts, 0.5-2.5 parts of water removal agents and 0.5-2.5 parts of anti-aging agents. The preparation method comprises the following two steps of: (1) slowly dripping polyhydric alcohol to isocyanate at the temperature of (85+ / -5) DEG C, then increasing the temperature to (90+ / -5) DEG C for continuous reaction, when the content of NCO groups is 14%-16%, adding organic silicon coupling agents, and reacting till the content of the NCO groups is 10%-12% so as to obtain a prepolymer; (2) adding the solvents, the catalysts, the water removal agents and the anti-aging agents to the prepolymer, uniformly stirring, and debubbling in vacuum (at vacuum degree less than or equal to -0.09MPa) to obtain the interface agent for the polyurethane caulking material. The interface agent disclosed by the invention has the characteristics of low viscosity, good impregnation property, high toughness, excellent hydrolysis-resistant property and alkali-resistant property, excellent adhesive property with concrete and the polyurethane caulking material, and the like.

Description

technical field [0001] The invention belongs to the field of building materials, and in particular relates to an interface agent for polyurethane caulking materials for ballastless tracks of high-speed railways and a preparation method thereof. Background technique [0002] At present, polyurethane caulking materials have been widely used in ballastless track structures of high-speed railways. Since the base slab and ballast slab of the high-speed railway ballastless track are long continuous pouring structures, affected by the temperature force and the dynamic load of the train, the displacement of the expansion joints set is large. According to the on-site test results and combined with theoretical calculations, the base The maximum deformation of the seam can reach more than 40%. Therefore, the polyurethane caulking material and concrete should have excellent bonding properties to prevent material degumming caused by large shrinkage, resulting in seam separation, and eve...

AI Technical Summary

Problems solved by technology

At present, there are many single-component polyurethane interface agents, but there are still the following problems in the application of high-speed railway ballastless track expansion joints: (1) The bonding substrates are mostly glass, ceramics, metals, organic polymers, wood, etc. , does not match the concrete interface; (2) the viscosity is high, the thickness of the coating is not easy to control, and it is easy to foam; (3) the curing time is long, the early bonding strength is poor, and even the bonding surface does not cure for a long time; (4) The material is brittle, and it is easy to break and fall off after long-term use; (5) The resistance to ultraviolet aging, heat aging and hydrolysis is poor

[0004] Chinese patent CN102140304A "A interface agent for polyurethane sealant and its preparation method" discloses a one-component polyurethane interface agent, which improves the bonding performance and aging resistance of the material through modification of epoxy resin, but introduces After epoxy resin, the viscosity of the material is high and the brittleness is relatively large. Under the action of long-term dynamic load and temperature force, it is easy to fall off or have a gap

The molecular chain structure of the isocyanate prepolymer prepared by this method is difficult to control, the molecular weight dispersion is large, and the molecular chain structure of the prepolymer produced in different batches is quite different.

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