High-strength, high-flame-retardant, low-exothermic polyurethane grouting reinforcement material for mines and its preparation method and application

Abstract

The invention belongs to the technical field of coal and rock chemical grouting reinforcement, and discloses a high-strength high-fire-retardant low-heat-release mining polyurethane grouting reinforcement material and a preparation method and application thereof. The material is obtained by matching a component I and a component II according to the volume ratio of one to one; the component I is prepared from, by weight, 70%-95% of isocyanate and 5%-30% of epoxy resin; the component II is prepared from, by weight, 30%-50% of flame retardant polyether polyol 1, 10%-20% of flame retardant polyether polyol 2, 25%-40% of plasticizers, 3%-8% of fire retardants, 2%-5% of curing agents, 0.5%-1% of catalyst, 1%-3% of antistatic agents and 0.5%-1% of foam stabilizer.

Description

technical field [0001] The invention belongs to the technical field of chemical grouting reinforcement for coal and rock mass, and in particular relates to a polyurethane grouting reinforcement material for mines with high strength, high flame retardancy and low heat release, and a preparation method and application thereof. Background technique [0002] Due to the particularity of the coal mine field, in addition to the requirements on the mechanical properties of the polymer grouting reinforcement materials used in underground coal mines, in order to ensure the safety of underground construction, it is also required to have a low heat of reaction and a high Flame retardancy and other characteristics, however, the existing polyurethane grouting reinforcement materials for coal mines often cannot meet all the above requirements at the same time, specifically in the following aspects: [0003] 1. The reaction temperature is higher. The existing coal mine safety industry stan...

AI Technical Summary

Problems solved by technology

Although there are some products currently on the market whose test results are lower than 140°C under a limited amount of reaction, when it is applied to the actual engineering grouting in coal mines, due to the large amount of grouting and the high aggregation of slurry materials, the polyurethane grout is in The heat generated during the curing reaction is relatively large, and because the environment is relatively closed, the heat dissipation conditions are seriously insufficient, so that the internal heat of the material accumulates more, and the temperature rises rapidly. Smoldering pyrolysis produces smoke or open flames, which can lead to serious disasters such as coal mine fires

[0004] 2. Poor flame retardancy

Although some grouting reinforcement products in the market meet the requirements of MT113-1995 "General Test Methods and Judgment Rules for Flame Retardancy and Antistatic Properties of Polymer Products Used in Underground Coal Mine", the uniformity of the slurry material and the construction environment must be considered in practical applications. Due to factors such as mechanical equipment and manual operation, the products currently on the market cannot fully meet the requirements for use. When the slurry material has too high a reaction temperature and insufficient flame retardant level during use, it is easy to cause safety accidents such as smoke or open flames.

[0005] 3. Insufficient mechanical properties

Polyurethane grouting reinforcement material contains isocyanate group, which is very easy to mix with H encountered in the actual construction process. 2 O reacts and produces CO 2 The gas makes the material continuously foam and expand during the curing process, and the mechanical strength of the foamed slurry consolidated body is greatly reduced, which can easily lead to the failure of grouting

In addition, due to the generation of a large amount of carbon dioxide gas, some fractured fault zones are subjected to high expansion pressure, which eventually leads to a large-scale overall lamina, roof collapse or collapse accidents

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