CN104893558A - Two-component PU (polyurethane) coating and preparation method thereof - Google Patents

Abstract

The invention discloses a two-component PU (polyurethane) coating. Firstly, castor oil is used for cross-linking prepolymers: a multifunctional group structure in the castor oil can cross-link the polymers to a certain extent, the cross-linking degree of the polymers is increased, so that the interaction force among molecular chains is increased, motion of the molecular chains is hindered, water molecules can hardly enter the molecular chains to enable the polymers to swell, and the water absorption of a film is reduced; meanwhile, the castor oil is a triglyceride of fatty acid, the film has the good hydrophobicity due to long nonpolar fatty acid chains in molecules of the castor oil, and the water absorption is further reduced; besides, ester groups in the castor oil have higher cohesive energy, so that the tensile strength of the film can be enhanced; ethyl cellulose has better heat resistance and thermoplasticity, has good compatibility with PU and can improve the comprehensive performance of the prepolymers; then blending modification is performed on the PU prepolymers and polysilsesquioxane.

Description

A kind of double-component polyurethane coating and preparation method thereof

Technical field

The present invention relates to a kind of coating, particularly relate to a kind of double-component polyurethane coating and preparation method thereof.

Background technology

Aqueous polyurethane emulsion has the advantages such as adjustable, the excellent sticking power of soft durometer and snappiness, be widely used in coating, tackiness agent and ink area, the synthesis mode of at present comparatively ripe anion aqueous polyurethane mainly by introducing hydrophilic radical and internal emulsification on polyurethane molecular segment, have certain water absorbability after film forming, film forming mechanical property, water tolerance, solvent resistance are poor.Usually cross-linking modified and the composite modified water tolerance and the mechanical property that improve glued membrane can be adopted;

In order to improve the performance such as mechanical property, water tolerance of urethane, reduce production cost simultaneously, the present invention replaces traditional petroleum chemicals polyvalent alcohol with Viscotrol C part, prepare a kind of New Emulsion, making its glue film performance obtain further improvement, is that a kind of renewable resources that utilizes is to prepare the effective ways of environment-friendly type high performance emulsion coatings.

Summary of the invention

The object of the invention just there is provided a kind of double-component polyurethane coating and preparation method thereof.

The present invention is achieved by the following technical solutions:

A kind of double-component polyurethane coating, it is characterized in that this coating is that the component A of 1.7-2:1 and B component form by mass ratio, described component A is made up of the raw material of following weight parts:

Ethyl cellulose 2-3, isophorone diisocyanate 50-67, polycarbonate diol 80-100, polysilsesquioxane 1.6-3, BDO 1.3-2, Diisopropyl azodicarboxylate 0.4-0.9, stannous octoate 0.1-0.17, fluoroboric acid 0.1-0.13, Viscotrol C 10-16;

Described B component is made up of the raw material of following weight parts:

Chloro-4, the 4'-diaminodiphenyl-methane 2-4 of 3,3'-bis-, polypropylene glycol 3-4, clorafin 4-6, light calcium carbonate 3-5.

A preparation method for double-component polyurethane coating, comprises the following steps:

Wherein the preparation method of component A comprises the following steps:

(1) polycarbonate diol is heated to 100-120 DEG C, reduce pressure the 1-2h that dewaters;

(2) joined by Viscotrol C in the Virahol of 5-10 times of weight, add fluoroboric acid, ethyl cellulose under agitation condition, insulated and stirred 1-2 hour at 60-65 DEG C, adds ammoniacal liquor, and regulator solution PH is 8-9, obtains Viscotrol C Inositol nf12 99;

(3) Viscotrol C Inositol nf12 99 is joined in the polycarbonate diol after dehydration, add stannous octoate, add isophorone diisocyanate under agitation condition, pass into nitrogen, add BDO, at 85-90 DEG C, react 1-2 hour, obtain base polyurethane prepolymer for use as;

(4) joined by above-mentioned Diisopropyl azodicarboxylate in 20-30 acetone doubly, stirring, is initiator solution;

(5) in above-mentioned base polyurethane prepolymer for use as, add polysilsesquioxane, drip above-mentioned initiator solution at 80-85 DEG C, dropwise rear ultrasonic disperse 10-20 minute, add each raw material of residue, dehydration, cooling discharging, revolves steaming and sloughs acetone, to obtain final product;

The preparation method of described B component comprises the following steps:

By chloro-for 3,3'-bis-4,4'-diaminodiphenyl-methanes, polypropylene glycol mixing, insulated and stirred 10-20 minute at 110-120 DEG C, adds clorafin, light calcium carbonate, is stirred to normal temperature, to obtain final product.

Using method:

First the dust of substrate surface, foreign material are cleaned out, basic unit must be smooth, solid and dry, A of the present invention, B component mixed according to weight ratio, stir, utilize round brush by mixture uniform application in substrate surface.

Advantage of the present invention is:

First the present invention adopts Viscotrol C crosslinking prepolymers body:

Polyfunctional group structure in Viscotrol C can give polymkeric substance certain being cross-linked, improve the crosslinking degree of polymkeric substance, the interaction force between molecular chain is increased, and molecular chain movement is obstructed, water molecules is difficult to enter molecular chain chien shih polymers swell, therefore glued membrane water-intake rate declines;

Viscotrol C is the Witepsol W-S 55 of lipid acid simultaneously, and in its molecule, the nonpolar fatty acid chain of long-chain makes glued membrane have good hydrophobicity, also reduce further water-absorbent;

Ester group simultaneously in Viscotrol C has higher internal cohesive energy, can improve the tensile strength of glued membrane;

And ethyl cellulose has good thermotolerance, thermoplasticity, with urethane, there is good consistency, the over-all properties of performed polymer can be improved;

Then by base polyurethane prepolymer for use as and polysilsesquioxane blending and modifying:

Due to the nanoparticle that polysilsesquioxane is containing Si-O-Si skeleton structure, can the organism of polymeric inner be stoped in the release being oxidized volatile matter in Sum decomposition process further by structure, possess good thermostability and be easy to functionalized simultaneously, can be incorporated in organic matrix well and improve polymer performance, under oxidated condition, also can generate SiO2 be coated on surface, can make material oxygen barrier, heat insulation, cause flame retardant effect to increase.

Embodiment

Below in conjunction with embodiment, the present invention is described in further detail:

Embodiment 1:

A kind of double-component polyurethane coating, it is characterized in that this coating is that the component A of 2:1 and B component form by mass ratio, described component A is made up of the raw material of following weight parts:

Ethyl cellulose 3, isophorone diisocyanate 67, polycarbonate diol 100, polysilsesquioxane 1.6, BDO 1.3, Diisopropyl azodicarboxylate 0.9, stannous octoate 0.17, fluoroboric acid 0.13, Viscotrol C 16;

Described B component is made up of the raw material of following weight parts:

Chloro-4, the 4'-diaminodiphenyl-methanes 3 of 3,3'-bis-, polypropylene glycol 3, clorafin 5, light calcium carbonate 4.

A preparation method for double-component polyurethane coating, comprises the following steps:

Wherein the preparation method of component A comprises the following steps:

(1) polycarbonate diol is heated to 120 DEG C, reduce pressure the 2h that dewaters;

(2) joined by Viscotrol C in the Virahol of 10 times of weight, add fluoroboric acid, ethyl cellulose under agitation condition, at 65 DEG C, insulated and stirred 1 hour, adds ammoniacal liquor, and regulator solution PH is 9, obtains Viscotrol C Inositol nf12 99;

(3) Viscotrol C Inositol nf12 99 is joined in the polycarbonate diol after dehydration, add stannous octoate, add isophorone diisocyanate under agitation condition, pass into nitrogen, add BDO, react 1 hour at 90 DEG C, obtain base polyurethane prepolymer for use as;

(4) being joined in the acetone of 20 times by above-mentioned Diisopropyl azodicarboxylate, stir, is initiator solution;

(5) in above-mentioned base polyurethane prepolymer for use as, add polysilsesquioxane, drip above-mentioned initiator solution at 85 DEG C, dropwise rear ultrasonic disperse 10 minutes, add each raw material of residue, dehydration, cooling discharging, revolves steaming and sloughs acetone, to obtain final product;

The preparation method of described B component comprises the following steps:

By chloro-for 3,3'-bis-4,4'-diaminodiphenyl-methanes, polypropylene glycol mixing, at 120 DEG C, insulated and stirred 10 minutes, adds clorafin, light calcium carbonate, is stirred to normal temperature, to obtain final product.

Performance test:

Tensile strength 5.7MPa;

Tear strength 17N/mm;

Elongation at break: 520%;

Watertightness: 0.3MPa, 30min: waterproof.

Claims (2)

1. a double-component polyurethane coating, it is characterized in that this coating is that the component A of 1.7-2:1 and B component form by mass ratio, described component A is made up of the raw material of following weight parts:

Ethyl cellulose 2-3, isophorone diisocyanate 50-67, polycarbonate diol 80-100, polysilsesquioxane 1.6-3, BDO 1.3-2, Diisopropyl azodicarboxylate 0.4-0.9, stannous octoate 0.1-0.17, fluoroboric acid 0.1-0.13, Viscotrol C 10-16;

Described B component is made up of the raw material of following weight parts:

Chloro-4, the 4'-diaminodiphenyl-methane 2-4 of 3,3'-bis-, polypropylene glycol 2-3, clorafin 4-6, light calcium carbonate 3-5.

2. a preparation method for double-component polyurethane coating as claimed in claim 1, is characterized in that comprising the following steps:

Wherein the preparation method of component A comprises the following steps:

(1) polycarbonate diol is heated to 100-120 DEG C, reduce pressure the 1-2h that dewaters;

(2) joined by Viscotrol C in the Virahol of 5-10 times of weight, add fluoroboric acid, ethyl cellulose under agitation condition, insulated and stirred 1-2 hour at 60-65 DEG C, adds ammoniacal liquor, and regulator solution PH is 8-9, obtains Viscotrol C Inositol nf12 99;

(3) Viscotrol C Inositol nf12 99 is joined in the polycarbonate diol after dehydration, add stannous octoate, add isophorone diisocyanate under agitation condition, pass into nitrogen, add BDO, at 85-90 DEG C, react 1-2 hour, obtain base polyurethane prepolymer for use as;

(4) joined by above-mentioned Diisopropyl azodicarboxylate in 20-30 acetone doubly, stirring, is initiator solution;

(5) in above-mentioned base polyurethane prepolymer for use as, add polysilsesquioxane, drip above-mentioned initiator solution at 80-85 DEG C, dropwise rear ultrasonic disperse 10-20 minute, cooling discharging, add each raw material of residue, dehydration, revolves steaming and sloughs acetone, to obtain final product;

The preparation method of described B component comprises the following steps:

By chloro-for 3,3'-bis-4,4'-diaminodiphenyl-methanes, polypropylene glycol mixing, insulated and stirred 10-20 minute at 110-120 DEG C, adds clorafin, light calcium carbonate, is stirred to normal temperature, to obtain final product.