CN115010902B

CN115010902B - Hydrophilic modified polyisocyanate and preparation method and application thereof

Info

Publication number: CN115010902B
Application number: CN202210756024.4A
Authority: CN
Inventors: 尹逊迪; 晋云全; 张延成; 王萃萃; 周操; 张萌鑫; 赵坤
Original assignee: Wanhua Chemical Group Co Ltd
Current assignee: Wanhua Chemical Group Co Ltd
Priority date: 2022-06-30
Filing date: 2022-06-30
Publication date: 2023-08-11
Anticipated expiration: 2042-06-30
Also published as: CN115010902A

Abstract

The invention provides hydrophilic modified polyisocyanate and a preparation method and application thereof, and the method can effectively and synchronously solve the problems of low reaction rate, high turbidity of the obtained product and dark color of the product in the existing preparation process of sulfonic acid modified polyisocyanate. The process comprises reacting a mass comprising component (a), component (b) and optionally component (c) to obtain the hydrophilically modified polyisocyanate: (a) at least one polyisocyanate, (b) at least one sulfamic acid, (c) at least one tertiary amine; in the sulfamic acid, the particle size is less than 10 weight percent, preferably less than 5 weight percent, more preferably less than 3 weight percent of particles with the particle size less than or equal to 900 meshes; and the particles having a particle size > 40 mesh are less than 10wt%, preferably less than 5wt%, more preferably less than 3wt%.

Description

Hydrophilic modified polyisocyanate and preparation method and application thereof

Technical Field

The invention relates to the field of modified polyisocyanates, in particular to a hydrophilic modified polyisocyanate, a preparation method and application thereof

Background

The aqueous isocyanate curing agents can be classified into polyether-modified polyisocyanate curing agents and sulfonic acid-modified polyisocyanate curing agents according to hydrophilic groups. Polyether-modified polyisocyanate curing agents, although widely accepted in the market, require the introduction of large amounts of polyether for good hydrophilicity, have the disadvantages of low effective isocyanate content and poor resistance, which inherent disadvantages limit the use of such curing agents. The sulfonic acid modified polyisocyanate curing agent has the advantages of high functionality, easy dispersion and the like, and the application range of the sulfonic acid modified polyisocyanate curing agent is wider and wider. However, how to increase the production efficiency of sulfonic acid-modified polyisocyanates, and how to obtain products with light color and low turbidity remain one of the difficulties plagued to those skilled in the art.

Patent document CN1190450C uses solid powders of 3- (cyclohexylamino) -propane sulfonic acid and 2- (cyclohexylamino) -ethane sulfonic acid to prepare a sulfonic acid-modified polyisocyanate, and the resulting modified polyisocyanate can be uniformly dispersed in water without requiring high shear force. CN104448232B the sulfonic acid modified polyisocyanate was prepared using 4- (cyclohexylamino) -butanesulfonic acid solid powder, and also obtained was excellent in properties. Both of the above documents use solid powder sulfonic acid to prepare a modified curing agent, which is a heterogeneous reaction, resulting in long reaction times, dark color, high turbidity of the product, and darkening of the color with prolonged storage time. In order to solve the disadvantages of heterogeneous reaction in terms of product performance, patent CN 110396173a and patent CN 110396165A respectively propose to introduce additives such as free radical scavengers and/or peroxide decomposers, antioxidants and the like into a reaction system, but the solutions only solve the problem of high color number, and cannot synchronously improve the disadvantages of high product turbidity and long reaction time.

Disclosure of Invention

The invention provides hydrophilic modified polyisocyanate and a preparation method and application thereof, and the method can effectively and synchronously solve the problems of low reaction rate, high turbidity of the obtained product and dark color of the product in the existing preparation process of sulfonic acid modified polyisocyanate.

The invention provides the following technical scheme for achieving the purpose:

the present invention provides a process for preparing a hydrophilically modified polyisocyanate, which comprises reacting a mass comprising component (a), component (b) and optionally component (c) to give the hydrophilically modified polyisocyanate:

(a) At least one of the group consisting of a polyisocyanate,

(b) At least one of the amino sulfonic acids is used for the preparation of a catalyst,

(c) At least one tertiary amine;

in the sulfamic acid, the particle size is less than 10 weight percent, preferably less than 5 weight percent, more preferably less than 3 weight percent of particles with the particle size less than or equal to 900 meshes; and the particles having a particle size > 40 mesh are less than 10wt%, preferably less than 5wt%, more preferably less than 3wt%.

In some embodiments, the sulfamic acid has the following structural formula:

wherein R is ₁ Is cyclohexyl, cyclohexylmethyl, p-methylcyclohexyl, 2, 3-dimethylcyclohexyl, 3, 5-trimethylcyclohexyl, 4-tert-butylcyclohexyl, cycloheptyl, cyclooctamethyl, 2-norbornyl, 2-adamantyl or 3, 5-dimethyl-1-adamantyl, R ₂ Is a straight or branched aliphatic group having 2 to 6 carbon atoms.

In some embodiments, the sulfamic acid (b) is selected from one or more of 2-cyclohexylamine ethane sulfonic acid, 3-cyclohexylamine propane sulfonic acid, 4-cyclohexylamine butane sulfonic acid.

In some embodiments, component (d) is optionally added to the reaction system: weak acids with pKa > 1;

preferably, the molar ratio of said weak acid to said sulfamic acid is between 0 and 0.3, preferably between 0.002 and 0.1.

In some embodiments, the component (d) is selected from one or more of dibutyl phosphate, di (2-ethylhexyl) phosphate, phosphoric acid, adipic acid.

In some embodiments, the method comprises reacting a material comprising the component (a), the component (b), the component (c), and the component (d) to obtain the hydrophilically modified polyisocyanate.

In some embodiments, the sulfamic acid is used in an amount of 0.5 to 10 percent by weight of the total mass of the polyisocyanate and sulfamic acid.

In some embodiments, the molar ratio of the tertiary amine to the sulfamic acid is from 0 to 1.1, preferably from 0.9 to 1.1.

In some embodiments, the reaction is carried out at 70-110 ℃.

In some embodiments, the polyisocyanate is an aliphatic, cycloaliphatic, araliphatic, and/or aromatic polyisocyanate; preferably, the polyisocyanate contains uretdione, isocyanurate, urethane, allophanate, biuret, iminooxadiazinedione and/or oxadiazinetrione structures; preferably, the diisocyanate used to prepare the polyisocyanate is selected from one or more of the group consisting of tetramethylene-1, 4-diisocyanate, pentamethylene-1, 5-diisocyanate, hexamethylene-1, 6-diisocyanate, dodecamethylene-1, 12-diisocyanate, 1, 4-cyclohexane diisocyanate, isophorone diisocyanate, 4' -dicyclohexylmethane diisocyanate, 4' -dicyclohexylpropane diisocyanate, 1, 4-benzene diisocyanate, 2, 4-toluene diisocyanate, 2, 6-toluene diisocyanate, 4' -diphenylmethane diisocyanate, 2' -diphenylmethane diisocyanate, 2,4' -diphenylmethane diisocyanate, tetramethylxylylene diisocyanate and p-xylylene diisocyanate;

in some embodiments, the tertiary amine is selected from one or more of N, N-dimethylbutylamine, N-diethylmethylamine, N-diisopropylethylamine, N-dimethylcyclohexylamine, N-methylpiperidine, and N-ethylmorpholine;

in some embodiments, a catalyst selected from one or more of a tertiary amine catalyst, an organometallic catalyst, which is different from the component c), is optionally further added to the reaction system;

in some embodiments, an antioxidant is also optionally added to the reaction system.

The invention also provides a hydrophilically modified polyisocyanate obtainable by the process described above.

The invention also provides the use of the hydrophilically modified polyisocyanates obtainable by the process described above or of the hydrophilically modified polyisocyanates described above for the preparation of coating agents, adhesives or sealants or as starting components for the production of polyurethane plastics.

The technical scheme provided by the invention has the following beneficial effects:

the inventors of the present invention have unexpectedly found that, based on the existing preparation process of sulfonic acid modified polyisocyanate, the use of sulfamic acid raw material with specific particle size requirements can effectively improve the disadvantages of low production efficiency, high turbidity of the product and deep color.

Detailed Description

In order that the invention may be readily understood, a further description of the invention will be provided with reference to the following examples. It should be understood that the following examples are only for better understanding of the present invention and are not meant to limit the present invention to the following examples.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The term "and/or" as may be used herein includes any and all combinations of one or more of the associated listed items.

Where specific experimental steps or conditions are not noted in the examples, they may be performed according to the operations or conditions of the corresponding conventional experimental steps in the art. The reagents or apparatus used were conventional products commercially available without the manufacturer's attention.

(a) At least one of the group consisting of a polyisocyanate,

(c) At least one tertiary amine;

wherein in the sulfamic acid of component (b), the particles with the particle size of less than or equal to 900 meshes are less than 10 weight percent, preferably less than 5 weight percent, and more preferably less than 3 weight percent; and the particles having a particle size > 40 mesh are less than 10wt%, preferably less than 5wt%, more preferably less than 3wt%.

The present invention is a proposal formed by improving the existing hydrophilic modified polyisocyanate technology, and the present inventors found that in the technology of preparing hydrophilic modified polyisocyanate by reacting sulfamic acid, polyisocyanate and optional tertiary amine, the sulfamic acid of solid particles and polyisocyanate react in a heterogeneous way, the reaction rate is low, and unreacted sulfamic acid is easy to exist in the form of particles in the product, so that the turbidity of the product is high, and meanwhile, the color number is increased continuously in the storage process of the product. The excessive sulfamic acid residue can seriously influence the stability of emulsion in the process of compounding hydrophilic modified polyisocyanate used as a curing agent and aqueous emulsion; in addition, the increase in product color number can also severely impact the appearance of the aqueous emulsion product. In the prior art, in order to make sulfamic acid react more completely, it is common practice to prolong the reaction time and increase the reaction temperature, and the unreacted sulfamic acid is oxidized and discolored at a high temperature for a long time in the preparation process, so that the color number of the product is increased. How to obtain hydrophilic modified polyisocyanates (sulfonic acid modified polyurethane) with low turbidity and low color number while improving production efficiency is one of the technical difficulties in the art. It is generally believed that the larger the particles, the smaller the specific surface area, the lower the reaction rate, and conversely, the smaller the particles, the larger the specific surface area, the faster the reaction rate. The inventors have found unexpectedly that, contrary to the conventional experience, when the particle size of sulfamic acid particles is smaller than a certain value, the production efficiency is rather low and the turbidity of the product is increased. And when the particle size of sulfamic acid is controlled so that the particle size is less than 10wt%, preferably less than 5wt%, more preferably less than 3wt% of 900 mesh particles are satisfied; and when the particles with the particle diameter of more than 40 meshes are less than 10wt percent, preferably less than 5wt percent, more preferably less than 3wt percent, the production efficiency can be effectively improved, and simultaneously, the turbidity of the product can be reduced and the color of the obtained product is lighter.

In the method, sulfamic acid with the particle diameter less than or equal to 900 meshes is added in a reaction system, the weight of particles is less than 10 percent, and the weight of particles with the particle diameter more than 40 meshes is less than 10 percent; in the case where the particle size of sulfamic acid satisfies the basic requirement, the sulfamic acid added in the reaction system has particles with particle size of less than or equal to 900 meshes, more preferably less than 5wt%, still more preferably less than 3wt%, and can further reduce the turbidity and color number of the product; similarly, in the case where the particle size of sulfamic acid satisfies the aforementioned basic requirements, the sulfamic acid added to the reaction system has particles having a particle size of > 40 mesh of more preferably less than 5% by weight, still more preferably less than 3% by weight, and can further reduce the turbidity and color number of the product. In some embodiments, the sulfamic acid added to the reaction system has a particle size D of, for example, 900 mesh < D.ltoreq.40 mesh, 800 mesh < D.ltoreq.50 mesh, 700 mesh < D.ltoreq.60 mesh, 60 mesh < D.ltoreq.40 mesh, 200 mesh < D.ltoreq.100 mesh, 400 mesh < D.ltoreq.200 mesh, 900 mesh < D.ltoreq.400 mesh, 100 mesh < D.ltoreq.60 mesh, and the like. As is well known to those skilled in the art, "mesh" means the number of mesh screens, the larger the number of mesh screens, the smaller the particle size of the undersize obtained by filtration through the screen. Regarding the control of the sulfamic acid particle size, conventional screen filtration can be used; for example, the product obtained by preparing sulfamic acid can be obtained by filtering and classifying the product by using a screen with a required mesh number; or dispersing the purchased sulfamic acid with acetone, and then filtering and grading the sulfamic acid by using a screen with the required mesh number; or may be obtained by grinding the sulfamic acid obtained by purchase, then filtering and classifying the ground sulfamic acid by using a screen of a desired mesh number, and the like.

In some embodiments, in the process of the present invention, component (d) is optionally also added to the reaction system: weak acids with pKa > 1. In some embodiments, the weak acid is preferably one or more of dibutyl phosphate, di (2-ethylhexyl) phosphate, phosphoric acid, adipic acid. In a preferred embodiment, the weak acid described above is added to the reaction system. The molar ratio of weak acid to sulfamic acid may be from 0 to 0.3, preferably from 0.002 to 0.1 (e.g., 0.002, 0.005, 0.01, 0.05, 0.1, etc.). The inventor discovers that when sulfamic acid meeting the particle size requirement of the invention is adopted, weak acid with pKa (acidity coefficient) more than 1 is added, and under the same process condition, the production efficiency can be further improved, and the turbidity and color number of the product can be reduced.

In some embodiments, the process of the present invention comprises reacting a material comprising component (a), component (b), component (c) and component (d) described above to obtain a hydrophilically modified polyisocyanate.

In the method of the present invention, the polyisocyanate, sulfamic acid and tertiary amine used are all materials conventionally used in the art for preparing hydrophilic modified polyisocyanates (sulfonic acid modified polyisocyanates), and the specific compound selection thereof can be referred to the conventional selection in the art, and the present invention is not particularly limited with respect to the specific compound selection of the above materials.

In some embodiments, the sulfamic acid of component (b) used has the following structural formula:

wherein R is ₁ Is cyclohexyl, cyclohexylmethyl, p-methylcyclohexyl, 2, 3-dimethylcyclohexyl, 3, 5-trimethylcyclohexyl, 4-tert-butylcyclohexyl, cycloheptyl, cyclooctamethyl, 2-norbornyl, 2-adamantyl or 3, 5-dimethyl-1-adamantyl, R ₂ Is a straight or branched aliphatic group having 2 to 6 carbon atoms. In some embodiments, the sulfamic acid is selected from one or more of 2-cyclohexylamine ethane sulfonic acid, 3-cyclohexylamine propane sulfonic acid, 4-cyclohexylamine butane sulfonic acid; in some embodiments, the sulfamic acid is selected from 3-cyclohexylamino propane sulfonic acid and/or 4-cyclohexylamino butane sulfonic acid. When the tertiary amine of component (c) is used simultaneously in the reaction system, the sulfamic acid may be partially or completely neutralized by the tertiary amine to form a salt before, during and/or after the reaction with the polyisocyanate.

In some embodiments, the polyisocyanate is an aliphatic, cycloaliphatic, araliphatic, and/or aromatic polyisocyanate. In some embodiments, the polyisocyanates having an average isocyanate functionality of 2.0 to 5.0 and an NCO content of 7.0 to 32.0% by weight may be unmodified or modified polyisocyanates as component (a) of the process of the invention.

In some embodiments, the polyisocyanate contains uretdione, isocyanurate, urethane, allophanate, biuret, iminooxadiazinedione, and/or oxadiazinetrione structures; the hydrophilically modified polyisocyanates thus obtained also correspondingly contain one or more of the structures described above. The abovementioned polyisocyanates can be prepared by one or more of the aliphatic, cycloaliphatic, aromatic and/or araliphatic diisocyanates according to the known processes, for example as described in the patent documents DE1670666A, DE1954093A, DE2414413A, DE2452532A, DE2641380A, DE3700209A, DE3900053A, DE3928503A, EP0336205A, EP0339396A, EP0798299A and the like.

Suitable diisocyanates for preparing the abovementioned polyisocyanates containing uretdione, isocyanurate, urethane, allophanate, biuret, iminooxadiazinedione and/or oxadiazinetrione structures are those which can be obtained by the phosgene process or non-phosgene process, for example any diisocyanate which is obtained by thermal decomposition of urethane. In some embodiments, the diisocyanate is a diisocyanate having a molecular weight of 100-500, having aliphatic, cycloaliphatic, araliphatic and/or aromatic linkages, such as a combination of one or more selected from the group consisting of tetramethylene-1, 4-diisocyanate, pentamethylene-1, 5-diisocyanate, hexamethylene-1, 6-diisocyanate, dodecamethylene-1, 12-diisocyanate, 1, 4-cyclohexane diisocyanate, isophorone diisocyanate, 4' -dicyclohexylmethane diisocyanate, 4' -dicyclohexylpropane diisocyanate, 1, 4-benzene diisocyanate, 2, 4-toluene diisocyanate, 2, 6-toluene diisocyanate, 4' -diphenylmethane diisocyanate, 2' -diphenylmethane diisocyanate, 2,4' -diphenylmethane diisocyanate, tetramethylxylylene diisocyanate and terephthal diisocyanate. In some preferred embodiments, the polyisocyanate is an isocyanurate group-containing polyisocyanate based on one or more of hexamethylene-1, 6-diisocyanate (HDI), isophorone diisocyanate (IPDI), and 4,4' -dicyclohexylmethane diisocyanate (H12 MDI).

In some embodiments, in the preparation process of the hydrophilic modified polyisocyanate containing the uretdione, isocyanurate, carbamate, allophanate, biuret, iminooxadiazinedione and/or oxadiazinetrione structure, an auxiliary agent such as an antioxidant, a free radical scavenger, an inhibitor and the like can be added, and the specific addition amount of the auxiliary agent can be used in the conventional dosage in the field, and can also be determined by a person skilled in the art according to the product requirement.

In some embodiments, the tertiary amine as component (c) may be those conventionally used in the art. In some embodiments, the tertiary amine as component (c) is selected from one or more of N, N-dimethylbutylamine, N-diethylmethylamine, N-diisopropylethylamine, N-dimethylcyclohexylamine, N-methylpiperidine, and N-ethylmorpholine. The tertiary amine as component (c) serves on the one hand to neutralize the sulfonic acid groups in the sulfamic acid to form sulfonates, and on the other hand as a phase transfer catalyst for the reaction to catalyze the reaction of the polyisocyanate and sulfamic acid.

In some embodiments, in the process of the invention for preparing hydrophilically modified polyisocyanates, it is also possible to add other materials which are permissible in the art of preparing hydrophilically modified polyisocyanates based on polyisocyanates, sulfamic acid and optionally tertiary amines, for example additional catalysts, for example one or more selected from tertiary amine catalysts, organometallic catalysts which are different from component c), the tertiary amine catalysts being selected from, for example, but not limited to: one or more of pyridine, picoline, benzyl dimethylamine, N-dimethylpiperazine; the organometallic catalyst may be selected from, for example, but not limited to: aluminum tris (ethyl-acetoacetate), tin n-octoate, zinc n-octoate, tin (II) 2-ethyl-1-hexanoate, dibutyltin (IV) dichloride, dibutyltin (IV) diacetate, dibutyltin (IV) dilaurate, dioctyltin (IV) diacetate or molybdenum glycolate. These conventional catalysts are used in amounts which can be readily determined by the person skilled in the art according to the reaction requirements, for example from 10 to 2000ppm, preferably from 100 to 500ppm, based on the total weight of the reaction mass.

In some embodiments, in the process for preparing the hydrophilically modified polyisocyanates of the invention, the polyisocyanate and sulfamic acid are reacted in the presence of a tertiary amine, optionally in an NCO-reactive solvent; solvents such as, but not limited to, acetone, butanone, cyclopentanone, cyclohexanone, ethyl acetate, butyl acetate, tetrahydrofuran, N-methylpyrrolidone, N-ethylpyrrolidone, toluene, xylene, chlorobenzene, propylene glycol methyl ether acetate, 1-methoxy-2-propyl acetate, 3-methoxy-N-butyl acetate, aromatic compounds, dimethyl carbonate, diethyl carbonate, butyrolactone, caprolactone, and methylcaprolactone, among others.

In some embodiments, an antioxidant may be added to further reduce color number, but is not required to be added in the process of preparing a hydrophilically modified polyisocyanate of the present invention. The antioxidant may be those conventionally added in the art, specifically, for example, aromatic amines and hindered phenols which can eliminate radicals and derivatives thereof, antioxidants such as phosphorus-and sulfur-containing organic compounds which can decompose hydroperoxides, or combinations thereof. The person skilled in the art can easily determine the amount of antioxidant added according to the actual need, for example, the amount of antioxidant added is 0% to 1.5% of the total mass of polyisocyanate (a) and sulfamic acid (b);

the amounts of sulfamic acid, polyisocyanate, tertiary amine used in the process of the invention are conventional in the art. In some embodiments, the sulfamic acid is used in an amount of 0.5 to 10 percent by weight of the total mass of polyisocyanate and sulfamic acid; the molar ratio of tertiary amine to sulfamic acid is from 0 to 1.1, preferably from 0.9 to 1.1.

In some embodiments, the process of the present invention, the polyisocyanate (a) and sulfamic acid (b) are reacted in the presence of an optional tertiary amine (c) at a temperature of from 70 to 110℃wherein the polyisocyanate (a) may be fed in one or more steps. Determination of the reaction end point is well known to the person skilled in the art, for example by testing the NCO content, for example when the NCO content reaches.+ -. 0.1% of theory, it being possible, of course, to take into account the extent of the reaction product permeation, and, for example, if the reaction product is cloudy, the extent of the reaction time.

The method of the invention can obtain the hydrophilic modified polyisocyanate with obviously reduced turbidity and color number, and the invention also provides the hydrophilic modified polyisocyanate prepared by the method.

The invention also provides the use of the hydrophilically modified polyisocyanates described above for the preparation of coating agents, adhesives or sealants or as starting components for the production of polyurethane plastics. In particular, for example, as a crosslinker in water-dispersible two-component coatings and adhesives. The hydrophilically modified polyisocyanates provided by the invention can also be used as starting components for preparing blocked polyisocyanates which are water-dispersible or which are present in the form of dispersions in water, suitable blocking agents being, for example, one or more of methyl ethyl ketoxime, 3, 5-dimethylpyrazole, diethyl malonate, ethyl acetoacetate, imidazole, epsilon-caprolactam. The hydrophilically modified polyisocyanates according to the invention can be used as crosslinking agents, in addition to two-component coatings and adhesives, as textile finishing, printing coating adhesives, as well as for crosslinking other aqueous dispersions or as auxiliaries for the moistening of paper.

The present invention is further illustrated by the following examples, which should not be construed as limiting the invention thereto.

Polyisocyanates a1 (Wanhua chemistry)HT-100, polyisocyanate based on HDI, NCO content = 21.7-22.2 wt%;

polyisocyanate a2 (bayer NZ1, polyisocyanate based on HDI and IPDI, NCO content=20wt%)

Sulfamic acid b1: in dioxane solvent, cyclohexylamine and 1, 4-butanesultone were reacted in a molar ratio of 3:1 at 80℃for 6h, filtered using a 40 mesh sieve, the filtrate was discarded and the collected solids on the 40 mesh sieve were washed with acetone to white. After drying, 4-cyclohexylamine butyl sulfonic acid b1 with the particle diameter D of more than 40 meshes and the purity of more than 99.5 percent is obtained.

Sulfamic acid b2: in dioxane solvent, with cyclohexylamine and 1, 4-butyl sultone in a molar ratio of 3:1 at 80 ℃ for 6 hours, using a 40 mesh screen filter to remove large particles, using a 60 mesh screen filter, discarding the filtrate, washing the solid collected on the 60 mesh screen with acetone to white. And drying to obtain the 4-cyclohexylamine butanesulfonic acid b2 with the particle size D of 60 meshes less than D and less than or equal to 40 meshes and the purity of more than 99.5 percent.

Sulfamic acid b3: after large particles were removed by filtration using a 100 mesh sieve in dioxane solvent with cyclohexylamine and 1, 4-butanesultone in a molar ratio of 3:1 at 80℃for 6h, the filtrate was filtered using a 200 mesh sieve, the filtrate was discarded, and the collected solids on the 200 mesh sieve were washed with acetone to white. And drying to obtain the 4-cyclohexylamine butanesulfonic acid b3 with the particle size D of 200 meshes less than D and less than or equal to 100 meshes and the purity of more than 99.5 percent.

Sulfamic acid b4: after large particles were removed by filtration using a 200 mesh sieve by reacting cyclohexylamine and 1, 4-butanesultone in a molar ratio of 3:1 in dioxane solvent at 80℃for 6 hours, the filtrate was filtered using a 400 mesh sieve, the filtrate was discarded, and the collected solid on the 400 mesh sieve was washed with acetone to white. And drying to obtain the 4-cyclohexylamine butanesulfonic acid b4 with the particle size D of 400 meshes less than or equal to D and less than or equal to 200 meshes and the purity of more than 99.5 percent.

Sulfamic acid b5: in dioxane solvent, with cyclohexylamine and 1, 4-butyl sultone in a molar ratio of 3:1 at 80 ℃ for 6 hours, using a 400 mesh screen filter to remove large particles, using a 900 mesh screen filter, discarding the filtrate, washing the collected solid on the 900 mesh screen with acetone to white. After drying, 4-cyclohexylamine butyl sulfonic acid b5 with the particle diameter D of 900 meshes less than or equal to D and less than or equal to 400 meshes and the purity of more than 99.5 percent is obtained.

Sulfamic acid b6: after large particles were removed by filtration using a 900 mesh sieve by reacting cyclohexylamine and 1, 4-butanesultone in a molar ratio of 3:1 in dioxane solvent at 80℃for 6 hours, the filtrate was filtered using a 1250 mesh sieve, the filtrate was discarded, and the collected solids on the 1250 mesh sieve were washed with acetone to white. After drying, 4-cyclohexylamine butyl sulfonic acid b6 with the particle diameter D being 1250 meshes less than D and less than or equal to 900 meshes and the purity being more than 99.5 percent is obtained.

Sulfamic acid b7: after large particles were removed by using a 60 mesh sieve by reacting cyclohexylamine and 1, 3-propane sultone in a molar ratio of 3:1 in a dioxane solvent at 30℃for 5 hours, the filtrate was collected by filtration using a 100 mesh sieve, the filtrate was discarded, and the collected solid on the 100 mesh sieve was washed with acetone to white. And drying to obtain the 3-cyclohexylamine propane sulfonic acid with the particle diameter D of 100 meshes less than or equal to D and less than or equal to 60 meshes and the purity of more than 99.5 percent.

Tertiary amine c1: n, N-dimethylcyclohexylamine, purchased from carbofuran reagent, purity 99%.

Tertiary amine c2: n-ethylmorpholine, purchased from carbofuran reagent, 99% purity.

Weak acid d1: dibutyl phosphate, purchased from ala Ding Shiji, 96% purity.

The testing method comprises the following steps:

NCO content test standard: GB/T12009.4-2016

2. Viscosity test standard: brookfield LV63#/3 rpm,25 DEG C

3. Color number test standard: measurement with Hazen Scale Using 723C-type visible spectrophotometer from Shanghai Meta analysis instruments Co., ltd

4. Turbidity test standard: measured using HACH 2100Q Portable Turbidimeter, units NTU.

5.SO ₃ ^- The content is as follows: obtained by theoretical calculation.

Example 1

380g (1.99 mol) of polyisocyanate a1, 19.75g (0.084 mol) of sulfamic acid b2 and 10.67g (0.084 mol) of tertiary amine c1 were added to a reaction system under stirring at 200rpm at 50℃in a four-necked round bottom flask equipped with a mechanical stirrer, a reflux tube, a thermometer and a nitrogen inlet and outlet, uniformly mixed, heated to 100℃for reaction for 5 hours, stopped, filtered through a 325 mesh screen, and cooled to room temperature to obtain sulfamic acid-modified polyisocyanate having the following characteristic data:

solids content: 100wt%

NCO content: 19.46wt%

Viscosity (25 ℃ C.). 5600 mPas

SO ₃ ^- The content is as follows: 1.64wt%

Color number: 9

Turbidity: 0.5

Example 2

380g (1.99 mol) of polyisocyanate a1, 18.57g (0.084 mol) of sulfamic acid b7 and 10.67g (0.084 mol) of tertiary amine c1 were added to a reaction system under stirring at 200rpm at 50℃in a four-necked round bottom flask equipped with a mechanical stirrer, a reflux tube, a thermometer and a nitrogen inlet and outlet, uniformly mixed, heated to 70℃for 7 hours, the reaction was stopped, filtered through a 325 mesh sieve, and cooled to room temperature to obtain sulfamic acid-modified polyisocyanate having the following characteristic data:

solids content: 100wt%

NCO content: 19.50wt%

Viscosity (25 ℃ C.). 5300 mPa.s

SO ₃ ^- The content is as follows: 1.64wt%

Color number: 4

Turbidity: 0.2

Example 3

380g (1.99 mol) of polyisocyanate a1, 19.75g (0.084 mol) of sulfamic acid b3 and 10.67g (0.084 mol) of tertiary amine c1 were added to the reaction system under stirring at 50℃and 300rpm in a four-necked round bottom flask equipped with a mechanical stirrer, a reflux tube, a thermometer and a nitrogen inlet and outlet, uniformly mixed, heated to 90℃for reaction for 6 hours, stopped the reaction, filtered through a 325 mesh sieve, and cooled to room temperature to obtain sulfamic acid-modified polyisocyanate having the following characteristic data:

solids content: 100wt%

NCO content: 19.45wt%

Viscosity (25 ℃ C.). 5800 mPa.s

SO ₃ ^- The content is as follows: 1.64wt%

Color number: 6

Turbidity: 0.2

Example 4

380g (1.99 mol) of polyisocyanate a1, 19.75g (0.084 mol) of sulfamic acid b4 and 9.66g (0.084 mol) of tertiary amine c2 were added to the reaction system under stirring at 50℃and 300rpm in a four-necked round bottom flask equipped with a mechanical stirrer, a reflux tube, a thermometer and a nitrogen inlet and outlet, uniformly mixed, heated to 80℃for 8 hours, the reaction was stopped, filtered through a 325 mesh sieve, and cooled to room temperature to obtain sulfamic acid-modified polyisocyanate having the following characteristic data:

solids content: 100wt%

NCO content: 19.47wt%

Viscosity (25 ℃ C.). 5400 mPas

SO ₃ ^- The content is as follows: 1.64wt%

Color number: 10

Turbidity: 0.2

Example 5

380g (1.99 mol) of polyisocyanate a1, 19.75g (0.084 mol) of sulfamic acid b5 and 10.67g (0.084 mol) of tertiary amine c1 were added to the reaction system under stirring at 200rpm at 50℃in a four-necked round bottom flask equipped with a mechanical stirrer, a reflux tube, a thermometer and a nitrogen inlet and outlet, uniformly mixed, heated to 110℃for reaction for 5 hours, stopped the reaction, filtered through a 325 mesh sieve, and cooled to room temperature to obtain sulfamic acid-modified polyisocyanate having the following characteristic data:

solids content: 100wt%

NCO content: 19.43wt%

Viscosity (25 ℃ C.). 5900 mPa.s

SO ₃ ^- The content is as follows: 1.64wt%

Color number: 10

Turbidity: 0.4

Example 6

380g (1.99 mol) of polyisocyanate a1, 17.97g (0.076 mol) of sulfamic acid b3,1.78g (0.008 mol) of sulfamic acid b1 and 10.67g (0.084 mol) of tertiary amine c1 are added into a reaction system under stirring at 50 ℃ and 200rpm in a four-necked round bottom flask equipped with a mechanical stirrer, a reflux tube, a thermometer and a nitrogen inlet and outlet, uniformly mixed, heated to 100 ℃ for reaction for 5 hours, stopped, filtered by a 325 mesh filter screen, and cooled to room temperature to obtain sulfamic acid modified polyisocyanate having the following characteristic data:

solids content: 100wt%

NCO content: 19.47wt%

Viscosity (25 ℃ C.). 5500 mPa.s

SO ₃ ^- The content is as follows: 1.64wt%

Color number: 26

Turbidity: 1.2

Example 7

380g (1.99 mol) of polyisocyanate a1, 18.86g (0.08 mol) of sulfamic acid b3,0.89g (0.004 mol) of sulfamic acid b1 and 10.67g (0.084 mol) of tertiary amine c1 are added into a reaction system under stirring at 50 ℃ and 200rpm in a four-necked round bottom flask equipped with a mechanical stirrer, a reflux tube, a thermometer and a nitrogen inlet and outlet, uniformly mixed, heated to 100 ℃ for reaction for 5 hours, stopped, filtered by a 325 mesh filter screen, and cooled to room temperature to obtain sulfamic acid modified polyisocyanate having the following characteristic data:

solids content: 100wt%

NCO content: 19.45wt%

Viscosity (25 ℃ C.). 5500 mPa.s

SO ₃ ^- The content is as follows: 1.64wt%

Color number: 13

Turbidity: 0.7

Example 8

380g (1.99 mol) of polyisocyanate a1, 17.97g (0.076 mol) of sulfamic acid b4,1.78g (0.008 mol) of sulfamic acid b6 and 10.67g (0.084 mol) of tertiary amine c1 are added into a reaction system under stirring at 50 ℃ and 200rpm in a four-necked round bottom flask equipped with a mechanical stirrer, a reflux tube, a thermometer and a nitrogen inlet and outlet, uniformly mixed, heated to 100 ℃ for reaction for 5 hours, stopped, filtered by a 325 mesh filter screen, and cooled to room temperature to obtain sulfamic acid modified polyisocyanate having the following characteristic data:

solids content: 100wt%

NCO content: 19.45wt%

Viscosity (25 ℃ C.). 5600 mPas

SO ₃ ^- The content is as follows: 1.64wt%

Color number: 32

Turbidity: 1.5

Example 9

380g (1.99 mol) of polyisocyanate a1, 18.86g (0.08 mol) of sulfamic acid b3,0.89g (0.004 mol) of sulfamic acid b6 and 10.67g (0.084 mol) of tertiary amine c1 are added into a reaction system under stirring at 50 ℃ and 200rpm in a four-necked round bottom flask equipped with a mechanical stirrer, a reflux tube, a thermometer and a nitrogen inlet and outlet, uniformly mixed, heated to 100 ℃ for reaction for 5 hours, stopped, filtered by a 325-mesh filter screen, and cooled to room temperature to obtain sulfamic acid modified polyisocyanate having the following characteristic data:

solids content: 100wt%

NCO content: 19.41wt%

Viscosity (25 ℃ C.). 6100 mPa.s

SO ₃ ^- The content is as follows: 1.64wt%

Color number: 14

Turbidity: 0.9

Example 10

380g (1.81 mol) of polyisocyanate a2, 19.75g (0.084 mol) of sulfamic acid b2 and 10.67g (0.084 mol) of tertiary amine c1 were added to the reaction system under stirring at 200rpm at 50℃in a four-necked round bottom flask equipped with a mechanical stirrer, a reflux tube, a thermometer and a nitrogen inlet and outlet, uniformly mixed, heated to 100℃for 5 hours, the reaction was stopped, filtered through a 325 mesh sieve, and cooled to room temperature to obtain sulfamic acid-modified polyisocyanate having the following characteristic data:

solids content: 100wt%

NCO content: 17.60wt%

Viscosity (25 ℃ C.). 5200 mPas

SO ₃ ^- The content is as follows: 1.64wt%

Color number: 8

Turbidity: 0.2

Example 11 (addition of weak acid compared to example 8)

380g (1.99 mol) of polyisocyanate a1, 17.97g (0.076 mol) of sulfamic acid b4,1.78g (0.008 mol) of sulfamic acid b6, 10.67g (0.084 mol) of tertiary amine c1 and 0.21g (0.001 mol) of weak acid d1 are added into a reaction system under stirring at 50 ℃ and 200rpm in a four-necked round bottom flask equipped with a mechanical stirrer, a reflux tube, a thermometer and a nitrogen inlet and outlet, uniformly mixed, heated to 100 ℃ for reaction for 5 hours, the reaction is stopped, filtered by a 325-mesh filter screen, and cooled to room temperature to obtain sulfamic acid modified polyisocyanate with the following characteristic data:

solids content: 100wt%

NCO content: 19.47wt%

Viscosity (25 ℃ C.). 5500 mPa.s

SO ₃ ^- The content is as follows: 1.64wt%

Color number: 16

Turbidity: 0.9

Comparative example 1 (compared to example 1)

380g (1.99 mol) of polyisocyanate a1, 19.75g (0.084 mol) of sulfamic acid b1 and 10.67g (0.084 mol) of tertiary amine c1 were added to the reaction system under stirring at 200rpm at 50℃in a four-necked round bottom flask equipped with a mechanical stirrer, a reflux tube, a thermometer and a nitrogen inlet and outlet, uniformly mixed, heated to 110℃for reaction for 8 hours, stopped the reaction, filtered through a 325 mesh sieve, and cooled to room temperature to obtain sulfamic acid-modified polyisocyanate having the following characteristic data:

solids content: 100wt%

NCO content: 19.48wt%

Viscosity (25 ℃ C.). 5400 mPas

SO ₃ ^- The content is as follows: 1.64wt%

Color number: 80

Turbidity: 6

The modified polyisocyanate prepared by sulfamic acid b1 having a particle size of > 40 mesh was used in comparative example 1 and example 1, and as a result, the reaction required temperature was higher and the reaction time was longer than in example 1, the reaction efficiency was remarkably lowered, and the color number and turbidity of the obtained product were remarkably increased.

Comparative example 2 (compared to example 1)

380g (1.99 mol) of polyisocyanate a1, 19.75g (0.084 mol) of sulfamic acid b6 and 10.67g (0.084 mol) of tertiary amine c1 were added to the reaction system under stirring at 200rpm at 50℃in a four-necked round bottom flask equipped with a mechanical stirrer, a reflux tube, a thermometer and a nitrogen inlet and outlet, uniformly mixed, heated to 110℃for reaction for 8 hours, stopped the reaction, filtered through a 325 mesh sieve, and cooled to room temperature to obtain sulfamic acid-modified polyisocyanate having the following characteristic data:

solids content: 100wt%

NCO content: 19.47wt%

Viscosity (25 ℃ C.). 5600 mPas

SO ₃ ^- The content is as follows: 1.64wt%

Color number: 130

Turbidity: 8.8

Compared with example 1, the sulfamic acid b6 with the particle size D of 1250 meshes < D less than or equal to 900 meshes is adopted to prepare the modified polyisocyanate, and as a result, compared with example 1, the temperature required for the reaction is higher, the reaction time is longer, the reaction efficiency is obviously reduced, and the color number and turbidity of the prepared product are obviously increased.

Comparative example 3 (compared to example 9)

380g (1.99 mol) of polyisocyanate a1, 16.79g (0.071 mol) of sulfamic acid b3,2.96g (0.013 mol) of sulfamic acid b6 and 10.67g (0.084 mol) of tertiary amine c1 were added to a reaction system under stirring at 50℃and 200rpm in a four-necked round bottom flask equipped with a mechanical stirrer, a reflux tube, a thermometer and a nitrogen inlet and outlet, and uniformly mixed, heated to 100℃for 8 hours, the reaction was stopped, filtered by a 325 mesh sieve, and cooled to room temperature to obtain sulfamic acid-modified polyisocyanate having the following characteristic data:

solids content: 100wt%

NCO content: 19.45wt%

Viscosity (25 ℃ C.). 5800 mPa.s

SO ₃ ^- The content is as follows: 1.64wt%

Color number: 65

Turbidity: 2.4

Compared with the comparative example 3 and the example 9, the proportion of sulfamic acid b6 with the particle size D of 1250 meshes < D less than or equal to 900 meshes in sulfamic acid is increased to more than 10 weight percent, the required reaction time is longer, the reaction efficiency is reduced, and the color number and turbidity of the prepared product are obviously increased.

Comparative example 4 (compared to example 7)

380g (1.99 mol) of polyisocyanate a1, 16.79g (0.071 mol) of sulfamic acid b3,2.96g (0.013 mol) of sulfamic acid b1 and 10.67g (0.084 mol) of tertiary amine c1 were added to a reaction system under stirring at 50℃and 200rpm in a four-necked round bottom flask equipped with a mechanical stirrer, a reflux tube, a thermometer and a nitrogen inlet and outlet, and uniformly mixed, heated to 100℃for 8 hours, the reaction was stopped, filtered by a 325 mesh sieve, and cooled to room temperature to obtain sulfamic acid-modified polyisocyanate having the following characteristic data:

solids content: 100wt%

NCO content: 19.50wt%

Viscosity (25 ℃ C.). 5300 mPa.s

SO ₃ ^- The content is as follows: 1.64wt%

Color number: 84

Turbidity: 2.8

Compared with the comparative example 7, the proportion of the sulfamic acid b1 with the particle size of more than 40 meshes in sulfamic acid is increased to more than 10 weight percent, the required reaction time is longer, the reaction efficiency is reduced, and the color number and turbidity of the prepared product are obviously increased.

Comparative example 5 (compared to example 10)

380g (1.81 mol) of polyisocyanate a2, 19.75g (0.084 mol) of sulfamic acid b6 and 10.67g (0.084 mol) of tertiary amine c1 were added to the reaction system under stirring at 200rpm at 50℃in a four-necked round bottom flask equipped with a mechanical stirrer, a reflux tube, a thermometer and a nitrogen inlet and outlet, uniformly mixed, heated to 100℃for 10 hours, the reaction was stopped, filtered through a 325 mesh sieve, and cooled to room temperature to obtain sulfamic acid-modified polyisocyanate having the following characteristic data:

solids content: 100wt%

NCO content: 19.55wt%

Viscosity (25 ℃ C.). 4900 mPa.s

SO ₃ ^- The content is as follows: 1.64wt%

Color number: 170

Turbidity: 12

Compared with example 10, sulfamic acid adopts sulfamic acid b6 with the particle size D of 1250 meshes < D less than or equal to 900 meshes, so that the required reaction time is longer, the reaction efficiency is reduced, and the color number and turbidity of the prepared product are obviously increased.

Comparative example 6

380g (1.99 mol) of polyisocyanate a1, 19.75g (0.084 mol) of sulfamic acid b6, 10.67g (0.084 mol) of tertiary amine c1 and 0.21g (0.001 mol) of weak acid d1 were added to a reaction system under stirring at 50℃and 200rpm in a four-necked round bottom flask equipped with a mechanical stirrer, a reflux tube, a thermometer and a nitrogen inlet and outlet, uniformly mixed, heated to 110℃for 8 hours, stopped the reaction, filtered through a 325 mesh sieve, and cooled to room temperature to obtain sulfamic acid-modified polyisocyanate having the following characteristic data:

solids content: 100wt%

NCO content: 19.48wt%

Viscosity (25 ℃ C.). 5500 mPa.s

SO 3-content: 1.64wt%

Color number: 115

Turbidity: 6.8

As can be seen from examples 1 to 10 and comparative examples 1 to 5, by controlling the proportion of sulfamic acid having a particle size of greater than 40 mesh and a particle size of 900 mesh or less in sulfamic acid in the reaction system, a hydrophilically modified polyisocyanate having a smaller color number and a low turbidity can be obtained at a relatively higher reaction rate. By comparing example 11, example 8, comparative example 6 and comparative example 2, it can be seen that further introduction of a weak acid in the case where the particle size of sulfamic acid satisfies the requirements of the present invention can further significantly reduce the color number and turbidity of the product.

It will be readily appreciated that the above embodiments are merely examples given for clarity of illustration and are not meant to limit the invention thereto. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. While still being apparent from variations or modifications that may be made by those skilled in the art are within the scope of the invention.

Claims

1. A process for preparing a hydrophilically modified polyisocyanate, which comprises reacting a mass comprising component (a), component (b) and component (c) to give the hydrophilically modified polyisocyanate:

(a) At least one of the group consisting of a polyisocyanate,

(c) At least one tertiary amine;

the sulfamic acid is characterized in that the weight of particles with the particle size less than or equal to 900 meshes is less than 10 percent, and the weight of particles with the particle size more than 40 meshes is less than 10 percent;

the sulfamic acid has the following structural formula:

2. The method of claim 1, wherein the sulfamic acid has less than 5 weight percent of particles less than or equal to 900 mesh.

3. The method according to claim 2, wherein the sulfamic acid has less than 3 weight percent of particles with a particle size of 900 mesh or less.

4. The method of claim 1, wherein the sulfamic acid has less than 5 weight percent of particles having a particle size of > 40 mesh.

5. The method of claim 4, wherein the sulfamic acid has less than 3 weight percent of particles with a particle size of > 40 mesh.

6. Process according to any one of claims 1-5, characterized in that the sulfamic acid (b) is selected from one or more of 2-cyclohexylaminoethanesulfonic acid, 3-cyclohexylaminopropanesulfonic acid, 4-cyclohexylaminobutanesulfonic acid.

7. The process according to any one of claims 1 to 5, wherein component (d) is optionally further added to the reaction system: weak acids with pKa > 1.

8. The method of claim 7, wherein the molar ratio of weak acid to sulfamic acid is from 0 to 0.3.

9. The method of claim 8, wherein the molar ratio of weak acid to sulfamic acid is from 0.002 to 0.1.

10. The method of claim 7, wherein component (d) is selected from one or more of dibutyl phosphate, di (2-ethylhexyl) phosphate, phosphoric acid, adipic acid.

11. The process of claim 7, comprising reacting a material comprising the component (a), the component (b), the component (c), and the component (d) to obtain the hydrophilically modified polyisocyanate.

12. The method according to any one of claims 1 to 5, wherein the sulfamic acid is used in an amount of 0.5 to 10 percent based on the total mass of the polyisocyanate and sulfamic acid;

and/or the molar ratio of the tertiary amine to the sulfamic acid is from 0.9 to 1.1;

and/or the reaction is carried out at 70-110 ℃.

13. The method according to any of claims 1 to 5, wherein the polyisocyanate is an aliphatic, cycloaliphatic, araliphatic and/or aromatic polyisocyanate;

and/or the tertiary amine is selected from one or more of N, N-dimethylbutylamine, N-diethylmethylamine, N-diisopropylethylamine, N-dimethylcyclohexylamine, N-methylpiperidine and N-ethylmorpholine;

and/or optionally adding a catalyst in the reaction system, wherein the catalyst is selected from one or more of tertiary amine catalyst and organic metal catalyst which are different from the component c);

and/or, optionally, an antioxidant is also added to the reaction system.

14. The method of claim 13, wherein the polyisocyanate contains uretdione, isocyanurate, urethane, allophanate, biuret, iminooxadiazinedione and/or oxadiazinetrione structures.

15. The method of claim 13, wherein the polyisocyanate used to prepare the polyisocyanate is selected from the group consisting of one or more of tetramethylene-1, 4-diisocyanate, pentamethylene-1, 5-diisocyanate, hexamethylene-1, 6-diisocyanate, dodecamethylene-1, 12-diisocyanate, 1, 4-cyclohexane diisocyanate, isophorone diisocyanate, 4' -dicyclohexylmethane diisocyanate, 4' -dicyclohexylpropane diisocyanate, 1, 4-benzene diisocyanate, 2, 4-toluene diisocyanate, 2, 6-toluene diisocyanate, 4' -diphenylmethane diisocyanate, 2' -diphenylmethane diisocyanate, 2,4' -diphenylmethane diisocyanate, tetramethylxylylene diisocyanate, and terephthal diisocyanate.

16. A hydrophilically modified polyisocyanate prepared according to the process of any one of claims 1 to 15.

17. Use of a hydrophilically modified polyisocyanate obtainable by a process according to any one of claims 1 to 15 or of a hydrophilically modified polyisocyanate according to claim 16 for the preparation of coating agents, adhesives or sealants or as starting component for the production of polyurethane plastics.