A kind of preparation method of reactive sealant resin

Abstract

The invention discloses a preparation method of a reactive sealant resin. The method comprises: (1) a hydroxyl-containing initiator is polymerized with an epoxy compound under the action of an alkali catalyst to obtain a polyether polyol; (2) In the polyether polyol obtained in step (1), an alkoxide reagent and a halogenated end-capping agent containing double bonds are added to react to obtain a double-bond-terminated polyether crude product, and the obtained crude product is refined to obtain Modified polyether product; (3) Under the action of hydrosilylation catalyst, the modified polyether and hydrogen-containing silane are subjected to silane end capping reaction to obtain the target product reactive sealant resin. The resin has excellent properties, good adhesion and paintability.

Description

technical field [0001] The invention relates to the field of sealants, in particular to a preparation method of a reactive sealant resin, which is mainly used for preparing elastic sealants. Background technique [0002] Since the 1980s, with the development of urban building modernization and the improvement of building function requirements, the variety and quantity of high-performance sealants for joint sealing of building structures in my country have increased. Acrylic, silicone and polyurethane sealants have been developed one after another, and the development is very rapid. Among them, silicone-based sealants have developed the fastest, with the advantages of fast curing speed, excellent high temperature resistance and weather resistance, but there are disadvantages such as low strength and unpaintable surface. Polyurethane sealants have high strength, oil and solvent resistance, and good wear resistance, but they have disadvantages such as easy foaming during curing...

AI Technical Summary

Problems solved by technology

[0006] 2. Synthesize a high molecular weight polyether with a double bond at one end and a hydroxyl group at one end, and then multiply it with a coupling agent (such as diisocyanate, etc.) to a modified polyether with a higher molecular weight, and then make a terminal siloxane through the end-capping process Based polyether, the molecular weight of the polyether used is relatively high, and the urethane group contained in the molecular chain is small, and a coupling reaction can be carried out by the coupling agent, which has little effect on the viscosity of the polymer, and there is no by-product of the coupling reaction , the process operation is relatively simple, but there are coupling agent residues in the product, and the weather resistance deviation

[0007] 3. Use the Williamson ether synthesis method to react the hydroxyl-terminated polyether with lower molecular weight with alkali metal or alkali metal hydroxide, couple with dichloromethane to double its molecular weight, and then react with allyl chloride to form a double-bonded polyether , through silicon-oxygen addition reaction to produce terminal siloxane-based polyether, but the molecular weight distribution of the chain extension product with dichloromethane is relatively wide, which directly affects the performance of sealants, and can only be used to prepare bifunctional resins

[0008] 4. Using bimetallic catalysts to synthesize high-molecular-weight hydroxyl-terminated polyethers, and then modify the polyethers to make siloxane-terminated polyethers through hydrosilicon addition, but the removal of by-product salts in the process is a difficult point. There is no reasonable solution yet