Preparation method for nitrated cellulose-modified waterborne polyurethane resin

Abstract

The invention discloses a preparation method for nitrated cellulose-modified waterborne polyurethane resin. The preparation method comprises the following steps of: (I) adding excessive diisocyanate and poly-dibasic alcohol into an organic tin catalyst, heating, and reacting; (II) after a reaction in the step (I) is completed, adding a non-hydrophilic chain extender and a hydrophilic chain extender with low molecular weights for reacting, adding acetone solvent for lowering viscosity along with continuous increase in the viscosity of the reaction system, and keeping the viscosity at 3000-4000cps; and (III) after the prepolymerization reaction is completed, adding an acetone solution of nitrated cellulose, uniformly stirring, adding a neutralizing agent, water and a post chain extender, emulsifying under the action of high-speed stirring shearing force to form an emulsion, and distilling for removing acetone to obtain the nitrated cellulose-modified waterborne polyurethane resin. The prepared waterborne polyurethane resin has high physical performance, hydrolysis resistance and solvent resistance; and when the waterborne polyurethane resin is taken as a coating agent, the attractiveness and handfeel of leather are enhanced, and the level of the leather is raised.

Description

technical field

[0001] The invention relates to a preparation process of water-based polyurethane resin, and a preparation method of nitrocellulose-modified water-based polyurethane resin. Background technique

[0002] Water-based polyurethane, also known as water-based polyurethane, is a polyurethane resin that introduces hydrophilic groups into the polyurethane molecular chain, so it has a strong affinity with water. It is a secondary component of polyurethane particles dispersed in the continuous phase (water). metacolloid system. Compared with solvent-based polyurethane, it has excellent properties such as solvent-free, pollution-free, and flame-retardant, and has gradually become an important direction for the development of the polyurethane industry. In recent years, with people's continuous research, water-based polyurethanes with various properties have been developed, which are widely used in adhesives, coatings, fabric finishing agents, etc. Among them, finishing ...

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