Single-component polyurethane sealant and low-temperature and rapid preparation method thereof

Abstract

A single-component polyurethane sealant and a low-temperature rapid preparation method thereof have the advantages that the single-component polyurethane sealant is high in tensile strength, shearingstrength and tearing strength, moderate in viscosity and good in storage stability; according to the preparation method of the single-component polyurethane sealant, the time is short, the preparationof the product can be completed within 2-3 hours, and the production efficiency is high; the reaction temperature in the preparation process does not exceed 100 DEG C; the preparation method of the single-component polyurethane sealant has the advantages of short high-temperature reaction time retention time, few reaction side reactions and low energy consumption, the preparation process is simple and easy to operate, the preparation can be completed by using the existing equipment, the preparation of the prepolymer is not limited in a reaction kettle any more, and the equipment cost and thelabor cost are greatly reduced; according to the preparation process of the single-component polyurethane sealant, prepolymer molecules always coexist with filler and functional additive molecules inthe production and formation processes, organic materials and inorganic materials can be better matched and interwoven, and the shearing strength, the tensile strength and the elongation at break of the product are improved.

Description

technical field

[0001] The invention relates to the technical field of adhesives, in particular to a single-component polyurethane sealant and a low-temperature, rapid preparation method. Background technique

[0002] The one-component moisture-curing polyurethane sealant is composed of NCO-terminated polyurethane prepolymers, fillers, plasticizers, catalysts, and functional additives. There are two methods for preparing one-component moisture-curing polyurethane sealants: One-step and two-step methods.

[0003] The one-step method is to prepare prepolymer in the presence of fillers. The general method is to mix polyols, plasticizers and fillers in a reactor, heat to 120-150°C, and then vacuum dehydrate to consume the moisture in the system. After the moisture content reaches the specified requirements, cool down to below 60°C, add polyisocyanate, catalyst and functional additives and stir to get the finished product. When the system cools down to below 60°C, a large amount...

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