Preparation method of modified cation waterborne polyurethane emulsion containing hydrophilic and hydrophobic side long chains and product thereof

Abstract

The invention relates to a preparation method of modified cation waterborne polyurethane emulsion containing hydrophilic and hydrophobic side long chains and a product thereof. The method comprises the following steps that raw materials are prepared; polyester glycol dehydration pretreatment is carried out; polyester glycol obtained after dehydration pretreatment is subjected to a prepolymerization reaction with an end alkyl polysiloxane linear body, a nonionic chain extender, a functionality chain extender and diisocyanate under catalyzing of a polymerization catalyst so that a prepolymer can be obtained; the prepolymer reacts with a nonionic chain extender and a part diluent to prepare an intermediate; the intermediate reacts with a silane coupling agent, and is emulsified to prepare the modified cation waterborne polyurethane emulsion. The product is a polyester type cation waterborne polyurethane high-polymer material containing hydrophilic and hydrophobic side long chains, wherein polysiloxane is embedded into a main chain of the material, a side chain is grafted with long-chain polyether and long-chain alkyl, and the silane coupling agent is connected into the tail end of the material; the film-forming ability is high, and serving as a film, the emulsion has obvious water-repellent, antifouling and easy dirt-removing abilities, is excellent in compatibility with a cation softening agent, and has an excellent low-temperature soft feature; the product is safe, environmentally friendly and convenient to use.

Description

technical field [0001] The invention relates to a functional polyurethane emulsion for finishing various types of textile substrates, fiber modification and functional finishing of textiles, in particular to a method for preparing a modified cationic water-based polyurethane emulsion containing hydrophilic and hydrophobic side long chains and its products . Background technique [0002] Waterborne polyurethane polymer materials are often used in the finishing process of various substrates. In the textile field, water-based polyurethane is often used for finishing textile substrates, color fixation of dyed textiles, anti-pilling of knitted textiles, fiber surface modification and special functional finishing of various textiles. In order to solve the problems of traditional water-based polyurethane materials such as low-temperature hardness, fatigue, low elongation and poor functionality, water-based polyurethane materials modified with various functional monomers are becomi...

AI Technical Summary

Problems solved by technology

However, this preparation method uses a small molecule trifunctional chain extender to introduce cross-links into the polyurethane polymer, resulting in the reaction process being difficult to control due to the rapid increase in the viscosity of the system and high viscosity. The short-chain cross-linking is also not conducive to the enrichment of fluorine-containing water-repellent chain segments to the surface of the film

In addition, the hydroxyl silicone oil used in the formulation is difficult to react with isocyanate groups to form effective chemical bonds with polyurethane polymers, resulting in severe polyurethane microphase separation and poor water resistance

At the same time, the molecular weight of fluorine-containing polyether polyols is large and the price is high, resulting in limited access to fluorine-containing functional side chains

All of these lead to the insignificant functionality of the material, and the water resistance, especially the alkali resistance, is not ideal.