A kind of airtight sealing polyurethane foam and preparation method thereof

Abstract

The invention discloses airtight plugging polyurethane foam and a preparation method thereof. The polyurethane foam comprises a component A and a component B, the component A comprises modified polyether polyol, water, a physical foaming agent, a catalyst and a chain extender, the component B comprises at least one of polyisocyanate and diisocyanate, and the modified polyether polyol is obtained by reaction modification of fluorine-containing benzenediol glycidyl ether and polyether polyol. According to the preparation method, polyether polyol is modified by utilizing fluorine-containing benzenediol glycidyl ether generated by epoxy chloropropane and fluorine-containing benzenediol; by adjusting the dosage of epichlorohydrin and fluorine-containing benzenediol and the dosage of isocyanate,cross-linked polyurethane foam containing fluorine and benzene on a main chain is generated, and the mechanical property and thermo-oxidative aging resistance of polyether polyurethane are improved.Meanwhile, unexpected discovery shows that the hydrophobicity of the finally prepared polyether polyurethane is improved by modifying the polyether polyol, so that condensation is prevented from gathering and permeating on the plugging foam, and the polyether polyurethane is durable.

Description

technical field [0001] The invention belongs to the technical field of polyurethane foam materials, and in particular relates to an air-tight polyurethane foam and its preparation. Background technique [0002] Whenever the rainy season comes in summer, or in humid southern regions, for electrical operating equipment in poorly sealed spaces, such as high and low voltage switch cabinets, ring network cabinets, terminal boxes, etc., the hot and humid air outside will pass through the electrical equipment and wiring. The cable half-layer / trench connection part, the hole part of the cable through the wall and other gaps enter the cavity. In a humid and hot environment, the inner wall of the product shell cools faster than the air in the cavity (thermal inertia), and the hot and humid air in the cavity will condense on the inner wall of the product shell. Dewdrops, the generated dewdrops will cause safety hazards to electrical equipment, and even seriously affect the stable opera...

AI Technical Summary

Problems solved by technology

[0003] Commonly used air sealing methods include 1) mechanical seal, which is suitable for spaces with regular shapes, but not suitable for holes and spaces with irregular shapes; 2) packing seals, for example, patent CN200710038800.2 discloses the use of inorganic fillers for cable fireproof seals The preparation method, which is simple to operate, saves time and labor, but compared with organic fillers, inorganic fillers have a large gap in toughness, insulation, heat insulation, etc.

Patent CN201710223150.2 discloses a method for airtight sealing of cables or pipelines through the structure. The patent uses polyisocyanate and polyisocyanate, polyether polyol and polyester polyol and other auxiliary materials to react to form polyurethane foam to realize cable or pipeline sealing. Airtight sealing of small gaps between pipelines and walls, switch cabinet bottom plates and other objects and between multiple cables or pipelines. Although the organic filler in this patent can seal every narrow gap, polyester polyurethane has excellent strength , oil resistance, heat and oxygen aging resistance, but due to the presence of ester bonds in polyester polyurethane, its hydrolysis resistance is poor, which greatly limits the popularization and application of polyester polyurethane as anti-condensation and air-tight sealing materials; Although polyether polyurethane has good low temperature resistance and hydrolysis resistance, its mechanical properties, oil resistance, and heat and oxygen aging resistance are poor. Once broken and leaky pores appear, it will not play the role of airtight sealing at all.

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