Internal crosslinking type self-extinction aqueous polyurethane dispersion and preparation method thereof
阅读说明：本技术 一种内交联型自消光水性聚氨酯分散体及其制备方法 (Internal crosslinking type self-extinction aqueous polyurethane dispersion and preparation method thereof ) 是由 姚红涛 司园精 吴后胜 张崇照 于 2021-06-17 设计创作，主要内容包括：本发明涉及水性聚氨酯树脂技术领域,尤其涉及一种内交联型自消光水性聚氨酯分散体及其制备方法。按照重量百分比计,其原料包括大分子多元醇7-40％,二异氰酸酯5-30％,亲水扩链剂0.4-2.0％,多元醇扩链剂0.1-5％,中和剂0.05-2％,后扩链剂0.1-5％,脂肪酮5-25％,水补充余量。本发明使用大分子三元醇为软段,无须外加交联剂便可获得具有内交联特性的聚氨酯乳液；该制备方法交联度高,工艺流程简单,并且具有较优的消光效果,适用于皮革、纸张、薄膜等表面需要哑光表面的产品。(The invention relates to the technical field of aqueous polyurethane resin, in particular to an internal crosslinking type self-extinction aqueous polyurethane dispersion and a preparation method thereof. The raw materials comprise, by weight, 7-40% of macromolecular polyol, 5-30% of diisocyanate, 0.4-2.0% of hydrophilic chain extender, 0.1-5% of polyol chain extender, 0.05-2% of neutralizer, 0.1-5% of post chain extender, 5-25% of aliphatic ketone and the balance of water. The invention uses macromolecule trihydric alcohol as a soft segment, and can obtain polyurethane emulsion with internal crosslinking characteristic without adding a crosslinking agent; the preparation method has the advantages of high crosslinking degree, simple process flow and excellent extinction effect, and is suitable for products with the surface needing matte surface, such as leather, paper, films and the like.)
1. The internal crosslinking type self-extinction aqueous polyurethane dispersion is characterized by comprising, by weight, 7-40% of macromolecular polyol, 5-30% of diisocyanate, 0.4-2.0% of hydrophilic chain extender, 0.1-5% of polyol chain extender, 0.05-2% of neutralizer, 0.1-5% of post chain extender, 5-25% of aliphatic ketone and the balance of water.
2. The internal crosslinking self-extinction aqueous polyurethane dispersion as claimed in claim 1, wherein the raw materials include, by weight, 10-20% of macromolecular polyol, 7-15% of diisocyanate, 0.5-1.5% of hydrophilic chain extender, 0.2-3% of polyol chain extender, 0.3-1.5% of neutralizer, 0.3-3% of post chain extender, 8-14% of aliphatic ketone, and the balance of water.
3. The internally crosslinked self-extinction aqueous polyurethane dispersion according to claim 1 or 2, wherein the macropolyol has an average molecular weight of 500-5000 and a functionality of 3.
4. An internally crosslinked self-extinguishing aqueous polyurethane dispersion according to any one of claims 1 to 3, wherein the macropolyol comprises one or more of polyoxypropylene triol, polyoxypropylene-oxyethylene copolyether triol, polycaprolactone triol and polylactide triol in combination.
5. An internally crosslinked self-matting aqueous polyurethane dispersion according to any one of claims 1 to 4, characterized in that the diisocyanate comprises hexamethylene diisocyanate, diphenylmethane-4, 4' -diisocyanate, diphenylmethylene diisocyanate, 1, 4-cyclohexanedimethyl diisocyanate, p-phenylene diisocyanate, 1, 3-xylylene diisocyanate, trimethyl-1, 6-hexamethylene diisocyanate, 2,2, 4-trimethylhexamethylene-1, 6-diisocyanate, o-xylylene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, cyclohexylene diisocyanate, xylylene diisocyanate, tetramethylxylene diisocyanate, toluene diisocyanate, naphthalene diisocyanate, phenylene diisocyanate, toluidine diisocyanate, diphenylmethane diisocyanate, and combinations derived from one or more of the foregoing diisocyanates.
6. An internally crosslinked self-extinction aqueous polyurethane dispersion according to any one of claims 1 to 5, characterised in that the hydrophilic chain extender comprises at least one of dimethylolpropionic acid, dimethylolbutyric acid, dimethylolacetic acid.
7. The internally crosslinked self-matting aqueous polyurethane dispersion according to claim 6 wherein the polyol chain extender comprises at least one of ethylene glycol, 1, 3-propylene glycol, 1, 4-butanediol, diethylene glycol, neopentyl glycol, 1, 6-hexanediol and 1, 4-cyclohexanedimethanol.
8. An internal crosslinking self-extinction aqueous polyurethane dispersion according to any one of claims 1 to 7, wherein the post-chain extender is a polyamine; the polyamine comprises one or more of ethylenediamine, isophorone diamine, hydrazine hydrate, N- (beta-aminoethyl) -gamma-aminopropyl trimethoxy silane, 4, 4-diphenyl methane diamine, N-beta- (aminoethyl) -gamma-aminopropyl methyl dimethoxy silane, hexamethylene diamine and pentamethylene diamine.
9. The internal crosslinking self-extinction aqueous polyurethane dispersion according to any one of claims 1 to 8, wherein the aliphatic ketone comprises at least one of dimethyl ketone, methyl ethyl ketone, and 2-pentanone.
10. A method for preparing the internal crosslinking type self-extinction aqueous polyurethane dispersion according to any one of claims 1 to 9, which comprises the following specific steps:
s1, reacting macromolecular polyol with diisocyanate to obtain a prepolymer A;
s2, adding a hydrophilic chain extender and a polyol chain extender into the prepolymer A, and reacting to obtain a prepolymer B;
s3, adding the aliphatic ketone and the neutralizing agent into the prepolymer B, and reacting to obtain an intermediate product;
and S4, adding the intermediate product into water, adding the chain extender, stirring, and distilling to obtain the product.
Technical Field
The invention relates to the technical field of aqueous polyurethane resin, in particular to an internal crosslinking type self-extinction aqueous polyurethane dispersion and a preparation method thereof.
Background
The high-gloss waterborne polyurethane coating has bright color and is popular with consumers for a long time. However, high gloss coatings have many disadvantages while providing high gloss. Firstly, the high-gloss coating can generate reflection after forming a film, so that the human eyes are damaged; secondly, when defects such as slight scratch, grease pollution, dust accumulation, fingerprint retention and the like appear on the glossy surface, the appearance is seriously influenced; with the change of the aesthetic sense of people, products with the surface decoration of extinction become more popular. The coating after the matte treatment is adopted on the surfaces of leather, paper, fabric and the like, soft, natural and elegant appearance and comfortable touch can be generated, and the plastic feeling caused by the brightness of the coating is eliminated.
The traditional extinction resin is prepared by dispersing an extinction agent into emulsion under the action of shearing force and mixing with functional auxiliaries with functions of anti-settling, thickening and the like. After film forming, a rough surface can be formed, so that light is subjected to diffuse reflection and scattering, and the extinction effect is achieved. Common matting agents are classified into 2 types of organic and inorganic matting agents. The inorganic delustering agent is mainly siliceous filler; the organic delustering agent is mainly metal soap, plant or animal oil and the like; the two extinction resins have obvious extinction effect, but the addition of the extinction agent causes the problems of easy cracking, poor hand feeling, reduced adhesive force, easy breaking and falling and the like of the coating. The addition of the matting material results in poor storage stability of the resin, uneven gloss of the coating, poor polishing resistance of the coating, and low transparency of the coating film. The self-extinction water-based polyurethane emulsion has the advantages that the particle size and the strength are improved, so that the emulsion particles generate micro-nano rough surfaces after being solidified on the surface of a base material, and the light scattering and refraction effects are enhanced, so that the extinction effect is achieved.
The waterborne polyurethane is influenced by the self structure, and has great influence on the application of low mechanical property, poor water resistance and the like. Modifying the product and improving the crosslinking density is one of effective means for improving the performance of the product. The important crosslinking modification comprises internal crosslinking and external crosslinking, wherein the internal crosslinking method is to introduce a crosslinking agent in the polymerization process to crosslink polyurethane macromolecules. Most of the self-extinction aqueous polyurethane emulsions modified by internal crosslinking currently reported use macrodiol as soft segment, and usually use trifunctional crosslinking agent TMP (such as patents CN110951039A, CN110669197A, CN110407996A, CN110041493A, CN 109517513A, CN107200823A, CN 106883370A) or isocyanate trimer (such as CN 107722236A, CN 106432667A, CN 103740250A), and the crosslinking efficiency obtained by the method is not ideal and the crosslinking degree is not high. The invention selects the tri-functionality polyhydric alcohol as the soft segment, can obtain the polyurethane emulsion with the internal crosslinking characteristic without adding a crosslinking agent, and has high crosslinking degree and simple process flow; the internal crosslinking self-extinction waterborne polyurethane prepared by the method is rarely reported.
Disclosure of Invention
The invention provides an internal crosslinking type self-extinction aqueous polyurethane dispersion, which adopts trifunctional macromolecular polyol as a soft segment, has simple process flow, does not need to add a crosslinking agent, and realizes the internal crosslinking type polyurethane with obvious extinction effect.
The invention provides an internal crosslinking type self-extinction aqueous polyurethane dispersion, which comprises, by weight, 7-40% of macromolecular polyol, 5-30% of diisocyanate, 0.4-2.0% of hydrophilic chain extender, 0.1-5% of polyol chain extender, 0.05-2% of neutralizer, 0.1-5% of post chain extender, 5-25% of aliphatic ketone and the balance of water.
In a preferred embodiment, the raw materials comprise, by weight, 10-20% of macromolecular polyol, 7-15% of diisocyanate, 0.5-1.5% of hydrophilic chain extender, 0.2-3% of polyol chain extender, 0.3-1.5% of neutralizer, 0.3-3% of post chain extender, 8-14% of aliphatic ketone, and the balance water.
In a preferred embodiment, the macromolecular polyol has an average molecular weight of 500-.
In a preferred embodiment, the macropolyol comprises a combination of one or more of polyoxypropylene triol, polyoxypropylene-oxyethylene copolyether triol, polycaprolactone triol, and polylactide triol.
In a preferred embodiment, the diisocyanate comprises hexamethylene diisocyanate, diphenylmethane-4, 4' -diisocyanate, diphenylmethylene diisocyanate, 1, 4-cyclohexanedimethyl diisocyanate, p-phenylene diisocyanate, 1, 3-phenylene diisocyanate, trimethyl-1, 6-hexamethylene diisocyanate, 2,2, 4-trimethylhexamethylene-1, 6-diisocyanate, o-xylylene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, cyclohexylene diisocyanate, xylylene diisocyanate, tetramethylxylene diisocyanate, toluene diisocyanate, naphthalene diisocyanate, phenylene diisocyanate, toluidine diisocyanate, diphenylmethane diisocyanate, and combinations derived from one or more of the foregoing diisocyanates.
In a preferred embodiment, the hydrophilic chain extender comprises at least one of dimethylolpropionic acid, dimethylolbutyric acid, dimethylolacetic acid.
In a preferred embodiment, the polyol chain extender comprises at least one of ethylene glycol, 1, 3-propylene glycol, 1, 4-butanediol, diethylene glycol, neopentyl glycol, 1, 6-hexanediol, and 1, 4-cyclohexanedimethanol.
In a preferred embodiment, the post-chain extender is a polyamine; the polyamine comprises one or more of ethylenediamine, isophorone diamine, hydrazine hydrate, N- (beta-aminoethyl) -gamma-aminopropyl trimethoxy silane, 4, 4-diphenyl methane diamine, N-beta- (aminoethyl) -gamma-aminopropyl methyl dimethoxy silane, hexamethylene diamine and pentamethylene diamine.
In a preferred embodiment, the aliphatic ketone comprises at least one of dimethyl ketone, methyl ethyl ketone, 2-pentanone.
The invention provides a preparation method of an internal crosslinking type self-extinction aqueous polyurethane dispersion, which comprises the following specific preparation steps:
s1, reacting macromolecular polyol with diisocyanate to obtain a prepolymer A;
s2, adding a hydrophilic chain extender and a polyol chain extender into the prepolymer A, and reacting to obtain a prepolymer B;
s3, adding the aliphatic ketone and the neutralizing agent into the prepolymer B, and reacting to obtain an intermediate product;
and S4, adding the intermediate product into water, adding the chain extender, stirring, and distilling to obtain the product.
Has the advantages that:
the internal crosslinking type self-extinction aqueous polyurethane dispersion obtained by the invention has the following advantages:
(1) the polyurethane emulsion with internal crosslinking characteristic can be obtained by using the macromolecule triol as a soft segment without adding a crosslinking agent;
(2) the process flow is simple, the crosslinking degree is high, a micro-nano rough surface can be formed, the extinction effect is strong, the processing is easy, and the method can be widely applied to various matte materials;
(3) the preparation method is simple and convenient, the reaction process is stable and controllable, the risk coefficient is low, the actual operability is strong, and large-scale mass production can be realized;
(4) the product has strong stability, is convenient to transport, and has important significance for the development of the matte polyurethane material.
Detailed Description
The disclosure may be understood more readily by reference to the following detailed description of preferred embodiments of the invention and the examples included therein. 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. In case of conflict, the present specification, including definitions, will control.
The term "prepared from …" as used herein is synonymous with "comprising". The terms "comprises," "comprising," "includes," "including," "has," "having," "contains," "containing," or any other variation thereof, as used herein, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.
The conjunction "consisting of …" excludes any unspecified elements, steps or components. If used in a claim, the phrase is intended to claim as closed, meaning that it does not contain materials other than those described, except for the conventional impurities associated therewith. When the phrase "consisting of …" appears in a clause of the subject matter of the claims rather than immediately after the subject matter, it defines only the elements described in the clause; other elements are not excluded from the claims as a whole.
When an amount, concentration, or other value or parameter is expressed as a range, preferred range, or as a range of upper preferable values and lower preferable values, this is to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed. For example, when a range of "1 to 5" is disclosed, the described range should be interpreted to include the ranges "1 to 4", "1 to 3", "1 to 2 and 4 to 5", "1 to 3 and 5", and the like. When a range of values is described herein, unless otherwise stated, the range is intended to include the endpoints thereof and all integers and fractions within the range.
The singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. "optional" or "any" means that the subsequently described event or events may or may not occur, and that the description includes instances where the event occurs and instances where it does not.
Approximating language, as used herein throughout the specification and claims, is intended to modify a quantity, such that the invention is not limited to the specific quantity, but includes portions that are literally received for modification without substantial change in the basic function to which the invention is related. Accordingly, the use of "about" to modify a numerical value means that the invention is not limited to the precise value. In some instances, the approximating language may correspond to the precision of an instrument for measuring the value. In the present description and claims, range limitations may be combined and/or interchanged, including all sub-ranges contained therein if not otherwise stated.
In addition, the indefinite articles "a" and "an" preceding an element or component of the invention are not intended to limit the number requirement (i.e., the number of occurrences) of the element or component. Thus, "a" or "an" should be read to include one or at least one, and the singular form of an element or component also includes the plural unless the stated number clearly indicates that the singular form is intended.
"Polymer" means a polymeric compound prepared by polymerizing monomers of the same or different types. The generic term "polymer" embraces the terms "homopolymer", "copolymer", "terpolymer" and "interpolymer". "interpolymer" means a polymer prepared by polymerizing at least two different monomers. The generic term "interpolymer" includes the term "copolymer" (which is generally used to refer to polymers prepared from two different monomers) and the term "terpolymer" (which is generally used to refer to polymers prepared from three different monomers). It also includes polymers made by polymerizing more monomers. "blend" means a polymer formed by two or more polymers being mixed together by physical or chemical means.
In order to solve the problems, the invention provides an internal crosslinking self-extinction aqueous polyurethane dispersion in a first aspect, which comprises, by weight, 7-40% of macromolecular polyol, 5-30% of diisocyanate, 0.4-2.0% of hydrophilic chain extender, 0.1-5% of polyol chain extender, 0.05-2% of neutralizer, 0.1-5% of post chain extender, 5-25% of aliphatic ketone, and the balance of water.
In some preferred embodiments, the raw materials comprise, by weight, 10-20% of macromolecular polyol, 7-15% of diisocyanate, 0.5-1.5% of hydrophilic chain extender, 0.2-3% of polyol chain extender, 0.3-1.5% of neutralizer, 0.3-3% of post chain extender, 8-14% of aliphatic ketone, and the balance water.
In some preferred embodiments, the macromolecular polyol has an average molecular weight of 500-.
More preferably, the macromolecular polyol has an average molecular weight of 1000-4000 and a functionality of 3.
In some preferred embodiments, the macropolyol comprises a combination of one or more of polyoxypropylene triol, polyoxypropylene-oxyethylene copolyether triol, polycaprolactone triol, polylactide triol.
In some preferred embodiments, the diisocyanate comprises hexamethylene diisocyanate, diphenylmethane-4, 4' -diisocyanate, diphenylmethylene diisocyanate, 1, 4-cyclohexanedimethylene diisocyanate, p-phenylene diisocyanate, 1, 3-phenylene diisocyanate, trimethyl-1, 6-hexamethylene diisocyanate, 2,2, 4-trimethylhexamethylene-1, 6-diisocyanate, o-xylylene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, cyclohexylene diisocyanate, xylylene diisocyanate, tetramethylxylene diisocyanate, toluene diisocyanate, naphthalene diisocyanate, phenylene diisocyanate, toluidine diisocyanate, diphenylmethane diisocyanate, and combinations derived from one or more of the foregoing diisocyanates.
In some preferred embodiments, the hydrophilic chain extender comprises at least one of dimethylolpropionic acid, dimethylolbutyric acid, dimethylolacetic acid.
In some preferred embodiments, the polyol chain extender comprises at least one of ethylene glycol, 1, 3-propylene glycol, 1, 4-butanediol, diethylene glycol, neopentyl glycol, 1, 6-hexanediol, and 1, 4-cyclohexanedimethanol.
In some preferred embodiments, the post-chain extender is a polyamine; the polyamine comprises one or more of ethylenediamine, isophorone diamine, hydrazine hydrate, N- (beta-aminoethyl) -gamma-aminopropyl trimethoxy silane, 4, 4-diphenyl methane diamine, N-beta- (aminoethyl) -gamma-aminopropyl methyl dimethoxy silane, hexamethylene diamine and pentamethylene diamine.
In some preferred embodiments, the neutralizing agent is triethanolamine and/or triethylamine.
Further preferably, the neutralizing agent is triethylamine.
In some preferred embodiments, the weight ratio of the hydrophilic chain extender, the neutralizing agent, and the post-chain extender is (1.3-4): (0.4-1): (0.3-1).
In some preferred embodiments, the aliphatic ketone comprises at least one of dimethyl ketone, methyl ethyl ketone, 2-pentanone.
Further preferably, the aliphatic ketone is dimethyl ketone and/or methyl ethyl ketone.
The invention provides a preparation method of an internal crosslinking type self-extinction aqueous polyurethane dispersion, which comprises the following specific preparation steps:
s1, reacting macromolecular polyol with diisocyanate to obtain a prepolymer A;
s2, adding a hydrophilic chain extender and a polyol chain extender into the prepolymer A, and reacting to obtain a prepolymer B;
s3, adding the aliphatic ketone and the neutralizing agent into the prepolymer B, and reacting to obtain an intermediate product;
and S4, adding the intermediate product into water, adding the chain extender, stirring, and distilling to obtain the product.
In some preferred embodiments, the reaction temperature of the step S1 is 60 to 95 ℃ and the reaction time is 1 to 3 hours.
In some preferred embodiments, the reaction temperature of the step S2 is 58 to 85 ℃ and the reaction time is 2 to 5 hours.
In some preferred embodiments, the reaction temperature of the S2 step is 50 to 60 ℃ and the reaction time is 0.5 to 1 h.
In some preferred embodiments, the stirring speed in the S4 step is 2000-2750rpm, and the stirring time is 0.5-2 h.
The invention adopts macromolecular polyalcohol with the average molecular weight of 1000-4000 and the functionality of 3 as a soft segment to react with diisocyanate to generate a high molecular polymer, has simple process flow, does not need to add a crosslinking agent additionally, and can obtain the polyurethane dispersoid with the internal crosslinking characteristic under the stable and controllable condition; the polyurethane emulsion obtained by sequentially reacting the hydrophilic chain extender, the polyol chain extender and the post chain extender with the prepolymer has high crosslinking degree and excellent extinction performance, and the cured polyurethane product has a micro-nano uniform and rough outer surface, can effectively scatter or refract light rays and achieves an extinction effect; under the control of specific raw materials and process, the invention not only solves the defect caused by the introduction of the flatting agent to polyurethane, but also obtains the polyurethane dispersoid with high crosslinking degree and strong flatting property.
Examples
In order to better understand the above technical solutions, the following detailed descriptions will be provided with reference to specific embodiments. It should be noted that the following examples are only for illustrating the present invention and should not be construed as limiting the scope of the present invention, and that the insubstantial modifications and adaptations of the present invention by those skilled in the art based on the above disclosure are still within the scope of the present invention. In addition, the raw materials are commercially available and the extraction methods of the extract are all conventional extraction methods, if not otherwise specified.
Example 1.
The embodiment provides an internal crosslinking type self-extinction aqueous polyurethane dispersion, which comprises, by weight, 15% of macromolecular polyol, 11% of diisocyanate, 0.7% of hydrophilic chain extender, 2.2% of polyol chain extender, 0.4% of neutralizer, 1% of post-chain extender, 8% of aliphatic ketone, and the balance of water.
The macromolecular polyalcohol is polycaprolactone triol, and the average molecular weight is 3000; purchased from Shenzhen Guanghua Wei province GmbH.
The diisocyanate is isophorone diisocyanate.
The hydrophilic chain extender is dimethylolbutyric acid; the polyol chain extender is 1, 4-butanediol.
The neutralizing agent is triethylamine.
The rear chain extender is ethylenediamine.
The aliphatic ketone is dimethyl ketone.
The preparation method of the internal crosslinking self-extinction aqueous polyurethane dispersion comprises the following steps:
s1, mixing macromolecular polyol and diisocyanate, and reacting for 2 hours at 90 ℃ to obtain a prepolymer A;
s2, cooling to 70 ℃, adding the hydrophilic chain extender and the polyol chain extender into the prepolymer A, and stirring and reacting at 70 ℃ for 4 hours to obtain a prepolymer B;
s3, cooling to 55 ℃, adding the aliphatic ketone and the neutralizing agent into the prepolymer B, and stirring for reaction for 0.5h to obtain an intermediate product;
and S4, transferring the intermediate product to a high-speed emulsifying machine, adding water, stirring for 20min at the rotating speed of 2000r/min, adding a rear chain extender, stirring for 60min at the rotating speed of 2000r/min, and distilling to obtain the product.
Example 2.
The embodiment provides an internal crosslinking type self-extinction aqueous polyurethane dispersion, which comprises, by weight, 14% of macromolecular polyol, 12% of diisocyanate, 1% of hydrophilic chain extender, 0.3% of polyol chain extender, 1% of neutralizer, 0.3% of post-chain extender, 10% of aliphatic ketone, and the balance of water.
The macromolecular polyol is polyoxypropylene triol, and the average molecular weight of the macromolecular polyol is 1000; shandong Lanxingdao Co., Ltd was purchased.
The diisocyanate is isophorone diisocyanate.
The hydrophilic chain extender is dimethylolbutyric acid; the polyol chain extender is diethylene glycol.
The neutralizing agent is triethylamine.
The rear chain extender is ethylenediamine.
The aliphatic ketone is methyl ethyl ketone.
The preparation method of the internal crosslinking self-extinction aqueous polyurethane dispersion comprises the following steps:
s1, mixing macromolecular polyol and diisocyanate, and reacting for 2 hours at 90 ℃ to obtain a prepolymer A;
s2, cooling to 70 ℃, adding the hydrophilic chain extender and the polyol chain extender into the prepolymer A, and stirring and reacting at 70 ℃ for 4 hours to obtain a prepolymer B;
s3, cooling to 60 ℃, adding the aliphatic ketone and the neutralizing agent into the prepolymer B, and stirring for reaction for 0.5h to obtain an intermediate product;
and S4, transferring the intermediate product to a high-speed emulsifying machine, adding water, stirring for 20min at the rotating speed of 2500r/min, adding a rear chain extender, stirring for 60min at the rotating speed of 2500r/min, and distilling to obtain the product.
Example 3.
The embodiment provides an internal crosslinking type self-extinction aqueous polyurethane dispersion, which comprises the following raw materials, by weight, 16% of macromolecular polyol, 12% of diisocyanate, 0.5% of hydrophilic chain extender, 2.7% of polyol chain extender, 0.4% of neutralizer, 1% of post-chain extender, 11% of fatty ketone, and the balance of water supplement.
The macromolecular polyol is polyoxypropylene triol, and the average molecular weight of the macromolecular polyol is 3000; shandong Lanxingdao Co., Ltd was purchased.
The diisocyanate is isophorone diisocyanate.
The hydrophilic chain extender is dimethylolbutyric acid; the polyol chain extender is 1, 3-propanediol.
The neutralizing agent is triethylamine.
The rear chain extender is ethylenediamine.
The aliphatic ketone is dimethyl ketone.
The preparation method of the internal crosslinking self-extinction aqueous polyurethane dispersion comprises the following steps:
s1, mixing macromolecular polyol and diisocyanate, and reacting for 2 hours at 90 ℃ to obtain a prepolymer A;
s2, cooling to 70 ℃, adding the hydrophilic chain extender and the polyol chain extender into the prepolymer A, and stirring and reacting at 70 ℃ for 4 hours to obtain a prepolymer B;
s3, cooling to 60 ℃, adding the aliphatic ketone and the neutralizing agent into the prepolymer B, and stirring for reaction for 0.5h to obtain an intermediate product;
and S4, transferring the intermediate product to a high-speed emulsifying machine, adding water, stirring for 20min at the rotating speed of 2500r/min, adding a rear chain extender, stirring for 60min at the rotating speed of 2500r/min, and distilling to obtain the product.
Comparative example 1.
The embodiment provides an internal crosslinking type self-extinction aqueous polyurethane dispersion, and the specific implementation manner is the same as that of embodiment 1; the difference lies in that: the macromolecular polyol is polybutylene adipate glycol, has an average molecular weight of 1000 and is purchased from Shandong Lanxingdong GmbH.
Comparative example 2.
The embodiment provides an internal crosslinking type self-extinction aqueous polyurethane dispersion, and the specific implementation manner is the same as that of embodiment 1; the difference lies in that: the addition amount of the hydrophilic chain extender is 5.5 percent; the hydrophilic chain extender is dimethylolbutyric acid.
Comparative example 3.
The embodiment provides an internal crosslinking type self-extinction aqueous polyurethane dispersion, and the specific implementation manner is the same as that of embodiment 1; the difference lies in that: the addition amount of the post chain extender is 5%.
Performance test method
Solid content G:
the same amounts of the polyurethane dispersions of examples 1 to 3 and comparative examples 1 to 3 were weighed out and heated in an oven at 120 ℃ for 2h, the mass m of the polyurethane dispersions before and after heating was recorded and the solids content G ═ m was calculatedBefore heating-mAfter heating)/mBefore heating100%. Each set of example samples was evaluated in 5 replicates.
Particle size:
the particle size of the polyurethane dispersions prepared in examples 1-3 and comparative examples 1-3 was measured using a Sympatec NAPOPHOX nanolaser particle sizer, germany. Each set of example samples was evaluated in 5 replicates. Gloss:
the gloss of the aqueous polyurethane dispersions obtained in examples 1 to 3 and comparative examples 1 to 3 was measured using a gloss meter manufactured by cushinka photoelectric instrument co. Each set of example samples was evaluated in 5 replicates.
Performance test data
TABLE 1 Performance test results
Solid content (%)
Degree of gloss
Particle size (nm)
Example 1
50
0.5
1600
Example 2
31
1.5
990
Example 3
40
0.5
1100
Comparative example 1
39
36
720
Comparative example 2
38
70
120
Comparative example 3
30
17
800
Finally, it is pointed out that the foregoing examples are illustrative only, serving to explain some of the characteristics of the process according to the invention. The appended claims are intended to claim as broad a scope as is contemplated, and the examples presented herein are merely illustrative of selected implementations in accordance with all possible combinations of examples. Accordingly, it is applicants' intention that the appended claims are not to be limited by the choice of examples illustrating features of the invention. Also, where numerical ranges are used in the claims, subranges therein are included, and variations in these ranges are also to be construed as possible being covered by the appended claims.