阅读说明：本技术 一种聚氨酯胶黏剂用液体多元醇及其制备方法 (Liquid polyol for polyurethane adhesive and preparation method thereof ) 是由 李海云 王永垒 江蓉 魏文静 朱梦泽 张雅文 于 2021-01-11 设计创作，主要内容包括：一种聚氨酯胶黏剂用液体多元醇及其制备方法,其原料包括以质量份计的以下组分：HAA副产物8-12份；DMF 10-15份；1,4-丁二醇1-1.5份；柠檬酸0.2-0.5份；己二酸0.1-0.3份；蓖麻油酸1.2-2.2份；异辛酸0.6-1.2份；催化剂,和活性白土。所述聚氨酯胶黏剂用液体多元醇具有2000-2500mPa·s的粘度、50-70mgKOH/g的羟值、＜5mgKOH/g的酸值。该产品及制备方法对HAA固化剂生产过程中产生的副产物进行了高附加值的综合利用,可用于作为常规聚氨酯胶黏剂的液体多元醇组分来使用。(The liquid polyol for the polyurethane adhesive and the preparation method thereof comprise the following raw materials in parts by mass: 8-12 parts of HAA by-product; 10-15 parts of DMF; 1-1.5 parts of 1, 4-butanediol; 0.2-0.5 part of citric acid; 0.1-0.3 part of adipic acid; 1.2-2.2 parts of ricinoleic acid; 0.6-1.2 parts of isooctanoic acid; a catalyst, and activated clay. The liquid polyol for a polyurethane adhesive has a viscosity of 2000-2500mPa · s, a hydroxyl value of 50-70mgKOH/g, and an acid value of < 5 mgKOH/g. The product and the preparation method comprehensively utilize byproducts generated in the production process of the HAA curing agent with high added value, and can be used as a liquid polyol component of a conventional polyurethane adhesive.)

1. A preparation method of liquid polyol for polyurethane adhesives comprises the following raw materials in parts by mass:

wherein, HAA is N, N, N ', N' -tetra (2-hydroxyethyl) adipamide, and the molecular structure is as follows:

2. the method for preparing a liquid polyol for polyurethane adhesives as claimed in claim 1, wherein the HAA by-product has a solid content of 85-90 wt% of a viscous liquid and the balance of water, and has a hydroxyl value of 800-850 mgKOH/g.

3. The method of preparing a liquid polyol for polyurethane adhesives according to claim 1, wherein the catalyst is dibutyltin dilaurate in an amount of 0.03 to 0.08% based on the amount of the HAA byproduct.

4. The process for producing a liquid polyol for polyurethane adhesives according to claim 1, wherein the amount of activated clay is 0.3 to 0.5% based on the amount of the HAA by-product.

5. The method for preparing a liquid polyol for polyurethane adhesives as set forth in any one of claims 1 to 5, further comprising the steps of:

A. adding HAA by-products and DMF in a formula amount into a reactor, heating to a first temperature, fully stirring and dissolving, then adding activated clay for adsorption and decoloration treatment, and performing suction filtration while hot to obtain a DMF solution phase;

B. adding a DMF solution phase into a reactor, adding 1, 4-butanediol, citric acid, adipic acid and a catalyst according to the formula amount, heating to a second temperature, vacuumizing, and performing vacuum esterification dehydration and DMF solvent removal reaction;

C. when the acid value of the system mixture is less than 5mgKOH/g, adding ricinoleic acid with the formula amount for chain extension reaction again, and then keeping the temperature at a third temperature under the vacuum condition for esterification reaction;

D. when the acid value of the system mixture is less than 10mgKOH/g, adding isooctanoic acid with the formula amount for end capping reaction, and then keeping the temperature at a fourth temperature under the vacuum condition for esterification reaction;

E. when the hydroxyl value of the system mixture reaches 50-70mgKOH/g, continuously heating to a fifth temperature, and carrying out reduced pressure distillation under the vacuum action to remove the unreacted isooctanoic acid;

F. and stopping the reaction when the acid value of the system mixture is less than 5mgKOH/g, relieving the vacuum, and discharging at high temperature to obtain the liquid polyol for the polyurethane adhesive.

6. The method as claimed in claim 5, wherein the first temperature is 110 ℃, the second temperature is 135-145 ℃, the third temperature is 135-145 ℃, the fourth temperature is 145-155 ℃, and the fifth temperature is 185-195 ℃.

7. The method of preparing a liquid polyol for polyurethane adhesives according to claim 5, wherein the vacuum degree is maintained at-0.096 to-0.099 MPa in the steps B, C and D.

8. The liquid polyol for polyurethane adhesives produced by the method for producing a liquid polyol for polyurethane adhesives according to claims 1 to 7.

9. The liquid polyol for polyurethane adhesives as claimed in claim 8, wherein the liquid polyol for polyurethane adhesives has a viscosity of 2000-2500mPa · s, a hydroxyl value of 50-70mgKOH/g, and an acid value of < 5 mgKOH/g.

Technical Field

The invention relates to the technical field of polyurethane, in particular to liquid polyol for a polyurethane adhesive and a preparation method thereof.

Background

HAA is a common powder coating curing agent product, is named as N, N, N ', N' -tetra (2-hydroxyethyl) adipamide, has the CAS number of 6334-25-4, and has the molecular structure as follows:

the composite material is synthesized by dimethyl adipate and diethanol amine under the action of an alkaline catalyst, has the advantages of environmental protection, no toxicity, good weather resistance and the like, and can be used for increasing the market consumption quickly at present.

However, during the synthesis process, some diethanolamine residues, esterification side reaction products formed by transesterification of dimethyl adipate and hydroxyl of diethanolamine, incomplete subsequent solvent crystallization and the like can be caused, so that a certain amount of byproducts, generally 50 to 100 kg, can be generated from HAA per ton of finished products. The part of byproducts are sticky substances which cannot be effectively applied at present, cannot bring value to enterprises, and more importantly, has the problem of environmental protection in treatment.

Therefore, there is a need to provide suitable methods to utilize the byproducts generated during HAA production as described above.

Disclosure of Invention

In order to solve the above technical problems, the present invention provides a liquid polyol for a polyurethane adhesive and a method for preparing the same.

The liquid polyol for the polyurethane adhesive comprises the following raw materials in parts by mass:

a catalyst, and

activated clay.

Wherein the HAA byproduct is purchased from Huangshan Huahui technology, Inc.; the HAA byproduct is viscous liquid with the solid content of 85-90 wt%, and the hydroxyl value is 800-850 mgKOH/g.

Wherein, the Chinese name of the HAA curing agent product is N, N, N ', N' -tetra (2-hydroxyethyl) adipamide, and the chemical structure is as follows:

wherein the catalyst is dibutyltin dilaurate, and the using amount of the catalyst is 0.03-0.08% of the mass of the HAA byproduct.

Wherein the consumption of the activated clay is 0.3-0.5% of the mass of the HAA byproduct.

The preparation method of the liquid polyol for the polyurethane adhesive further comprises the following steps:

A. adding HAA by-products and DMF in a formula amount into a reactor, heating to a first temperature, fully stirring and dissolving, then adding activated clay for adsorption and decoloration treatment, and performing suction filtration while hot to obtain a DMF solution phase;

B. adding a DMF solution phase into a reactor, adding 1, 4-butanediol, citric acid, adipic acid and a catalyst according to the formula amount, heating to a second temperature, vacuumizing, and performing vacuum esterification dehydration and DMF solvent removal reaction;

C. when the acid value of the system mixture is less than 5mgKOH/g, adding ricinoleic acid with the formula amount for chain extension reaction again, and then keeping the temperature at a third temperature under the vacuum condition for esterification reaction;

D. when the acid value of the system mixture is less than 10mgKOH/g, adding isooctanoic acid with the formula amount for end capping reaction, and then keeping the temperature at a fourth temperature under the vacuum condition for esterification reaction;

E. when the hydroxyl value of the system mixture reaches 50-70mgKOH/g, continuously heating to a fifth temperature, and carrying out reduced pressure distillation under the vacuum action to remove the unreacted isooctanoic acid;

F. and stopping the reaction when the acid value of the system mixture is less than 5mgKOH/g, relieving the vacuum, and discharging at high temperature to obtain the liquid polyol for the polyurethane adhesive.

Wherein, the reactor is a reaction kettle.

Wherein, in the step A, the first temperature is 100-110 ℃, preferably 105 ℃.

Wherein, in the step A, the adsorption decoloring treatment is carried out for 20-40min, preferably 30 min.

Wherein, in the step B, the second temperature is 135-145 ℃, preferably 140 ℃.

Wherein, in the steps B, C and D, the vacuum degree is kept between-0.096 and-0.099 MPa, and preferably-0.098 MPa.

Wherein, in the step C, the third temperature is 135-145 ℃, preferably 140 ℃.

Wherein, in the step D, the fourth temperature is 145-155 ℃, preferably 150 ℃.

Wherein, in the step E, the fifth temperature is 185-195 ℃, preferably 190 ℃.

The invention also provides the liquid polyol for the polyurethane adhesive, which is prepared by the preparation method.

Wherein the liquid polyol for polyurethane adhesives is a pale yellow viscous liquid in appearance, and has a viscosity of 2000-2500mPa · s, a hydroxyl value of 50-70mgKOH/g, and an acid value of < 5 mgKOH/g.

Compared with the prior art, the invention has the following advantages:

1. the invention takes HAA byproduct as main raw material, and 1, 4-butanediol, citric acid, adipic acid, ricinoleic acid, isooctanoic acid and other raw materials are matched for polymerization reaction to obtain the liquid polyol for polyurethane adhesives, wherein the acid value is less than 5mgKOH/g, the hydroxyl value is 50-70mgKOH/g, and the viscosity is 2000-2500 mPa.s.

2. The liquid polyol for the polyurethane adhesive and the preparation method thereof comprehensively utilize byproducts generated in the production process of the HAA curing agent with high added value, can be used as a liquid polyol component of the conventional polyurethane adhesive, and meet the application requirement of the polyester polyol for the conventional commercially available polyurethane adhesive.

Detailed Description

The present invention will be further described in detail with reference to the following examples for better understanding of the present invention, and therefore, the following examples are illustrative only and not intended to limit the scope of the present invention, and those skilled in the art can make certain insubstantial modifications and adaptations of the present invention based on the present invention.

Example 1

A preparation method of liquid polyol for polyurethane adhesives comprises the following raw materials in parts by mass:

the preparation method of the liquid polyol for the polyurethane adhesive further comprises the following steps:

A. adding HAA by-products and DMF solvent in a formula amount into a reaction kettle, heating to 105 ℃, fully stirring and dissolving, then adding activated clay for adsorption and decoloration for 30min, and performing suction filtration while hot to obtain a DMF solution phase;

B. adding a DMF solution phase into a reaction kettle, adding 1, 4-butanediol, citric acid, adipic acid and a catalyst dibutyltin dilaurate in formula amount, heating to 145 ℃, starting a vacuum system, keeping the vacuum degree at about-0.098 MPa, and performing vacuum esterification dehydration reaction and DMF solvent removal;

C. when the acid value of the system mixture is less than 5mgKOH/g, ricinoleic acid with the formula amount is added for chain extension reaction again, and then the esterification reaction is carried out under the action of high vacuum (-0.098Mpa) and the temperature is kept at 140 ℃;

D. when the acid value of the system mixture is less than 10mgKOH/g, adding isooctanoic acid with the formula amount for carrying out end capping reaction, and carrying out esterification reaction at 150 ℃ under the condition of high vacuum (-0.098 Mpa);

E. when the hydroxyl value of the system mixture reaches 50-70mgKOH/g, the temperature is continuously increased to 192 ℃, reduced pressure distillation is carried out under the vacuum action, and the unreacted raw material isooctanoic acid is removed;

F. when the acid value is less than 5mgKOH/g, stopping the reaction, removing the vacuum system, and discharging at high temperature to obtain the liquid polyol for the polyurethane adhesive.

The liquid polyol for polyurethane adhesives prepared was a pale yellow viscous liquid in appearance, and had a viscosity of 2480 mPas (25 ℃ C.) and a hydroxyl value of 52 mgKOH/g.

Example 2:

a preparation method of liquid polyol for polyurethane adhesives comprises the following raw materials in parts by mass:

the preparation method of the liquid polyol for the polyurethane adhesive further comprises the following steps:

A. adding HAA by-products and DMF solvent in a formula amount into a reaction kettle, heating to 102 ℃, fully stirring and dissolving, then adding activated clay for adsorption and decoloration treatment for 20min, and performing suction filtration while hot to obtain a DMF solution phase;

B. adding a DMF solution phase into a reaction kettle, adding 1, 4-butanediol, citric acid, adipic acid and a catalyst according to the formula amount, heating to 135 ℃, starting a vacuum system, keeping the vacuum degree at about-0.096 MPa, and performing vacuum esterification dehydration reaction and DMF solvent removal;

C. when the acid value of the system mixture is less than 5mgKOH/g, ricinoleic acid with the formula amount is added for chain extension reaction again, and then the esterification reaction is carried out under the action of high vacuum (-0.096Mpa) and the temperature is kept at 145 ℃;

D. when the acid value of the reaction mixture is less than 10mgKOH/g, adding isooctanoic acid with the formula amount for end capping reaction, and carrying out esterification reaction at 145 ℃ under the condition of high vacuum (-0.096 Mpa);

E. when the hydroxyl value of the reaction mixture reaches 50-70mgKOH/g, the temperature is continuously increased to 195 ℃, reduced pressure distillation is carried out under the vacuum action, and the unreacted raw material isooctanoic acid is removed;

F. when the acid value is less than 5mgKOH/g, stopping the reaction, removing the vacuum system, and discharging at high temperature to obtain the liquid polyol for the polyurethane adhesive.

The liquid polyol for polyurethane adhesives prepared was a pale yellow viscous liquid in appearance, and had a viscosity (25 ℃ C.) of 2025 mPas and a hydroxyl value of 67 mgKOH/g.

Example 3:

a preparation method of liquid polyol for polyurethane adhesives comprises the following raw materials in parts by mass:

the preparation method of the liquid polyol for the polyurethane adhesive further comprises the following steps:

A. adding HAA by-products and DMF solvent in a formula amount into a reaction kettle, heating to 110 ℃, fully stirring and dissolving, then adding activated clay for adsorption and decoloration treatment for 40min, and performing suction filtration while hot to obtain a DMF solution phase;

B. adding a DMF solution phase into a reaction kettle, adding 1, 4-butanediol, citric acid, adipic acid and a catalyst according to the formula amount, heating to 140 ℃, starting a vacuum system, keeping the vacuum degree at about-0.098 MPa, and performing vacuum esterification dehydration reaction and DMF solvent removal;

C. when the acid value of the system mixture is less than 5mgKOH/g, ricinoleic acid with the formula amount is added for chain extension reaction again, and then the esterification reaction is carried out under the action of high vacuum (-0.098Mpa) and the temperature is kept at 135 ℃;

D. when the acid value of the reaction mixture is less than 10mgKOH/g, adding isooctanoic acid with the formula amount for end capping reaction, and carrying out esterification reaction at 155 ℃ under the condition of high vacuum (-0.098 Mpa);

E. when the hydroxyl value of the reaction mixture reaches 50-70mgKOH/g, continuously heating to 185 ℃, and carrying out reduced pressure distillation under the vacuum action to remove the unreacted raw material isooctanoic acid;

F. when the acid value is less than 5mgKOH/g, stopping the reaction, removing the vacuum system, and discharging at high temperature to obtain the liquid polyol for the polyurethane adhesive.

The liquid polyol for polyurethane adhesives prepared was a pale yellow viscous liquid in appearance, and had a viscosity (25 ℃ C.) of 2346 mPas and a hydroxyl value of 59 mgKOH/g.

Example 4:

a preparation method of liquid polyol for polyurethane adhesives comprises the following raw materials in parts by mass:

the preparation method of the liquid polyol for the polyurethane adhesive further comprises the following steps:

A. adding HAA by-products and DMF solvent in a formula amount into a reaction kettle, heating to 108 ℃, fully stirring and dissolving, then adding activated clay for adsorption and decoloration for 35min, and performing suction filtration while hot to obtain a DMF solution phase;

B. adding a DMF solution phase into a reaction kettle, adding 1, 4-butanediol, citric acid, adipic acid and a catalyst according to the formula amount, heating to 142 ℃, starting a vacuum system, keeping the vacuum degree at about-0.099 MPa, and performing vacuum esterification dehydration reaction and DMF solvent removal;

C. when the acid value of the system mixture is less than 5mgKOH/g, ricinoleic acid with the formula amount is added for chain extension reaction again, and then the esterification reaction is carried out under the action of high vacuum (-0.099Mpa) and the temperature is kept at 140 ℃;

D. when the acid value of the system mixture is less than 10mgKOH/g, adding isooctanoic acid with the formula amount for carrying out end capping reaction, and carrying out esterification reaction at 148 ℃ under the condition of keeping high vacuum (-0.099 Mpa);

E. when the hydroxyl value of the system mixture reaches 50-70mgKOH/g, the temperature is continuously increased to 190 ℃, reduced pressure distillation is carried out under the vacuum action, and the unreacted raw material isooctanoic acid is removed;

F. when the acid value is less than 5mgKOH/g, stopping the reaction, removing the vacuum system, and discharging at high temperature to obtain the liquid polyol for the polyurethane adhesive.

The liquid polyol for polyurethane adhesives prepared was a pale yellow viscous liquid in appearance, and had a viscosity (25 ℃ C.) of 2270 mPas and a hydroxyl value of 63 mgKOH/g.

Comparative example 1

The polyurethane adhesive is prepared from a commercially available common liquid polyol for polyurethane adhesives, with the model number of L3016 and the hydroxyl value of 58mgKOH/g, which is purchased from Zhengzhou hectarest specialized engineering and technology Limited.

Testing the performance of the adhesive:

toluene diisocyanate and liquid polyol for polyurethane adhesives of examples and comparative examples are mixed according to the molar ratio of isocyanic groups to hydroxyl groups of 1:1, after uniform mixing, sizing is completed within 10min, the thickness of a glue layer is 0.2mm, the glue layer is coated on the surface of an aluminum test piece, and after curing is carried out for 15min by a flat vulcanizing machine, the curing conditions are as follows: the pressure is 3Mpa, and the temperature is 130 ℃; the tensile shear strength is measured according to the GB/T7124-2008 'determination of adhesive tensile shear strength' standard. The test results are shown in Table 1.

Table 1 results of performance test of adhesives prepared from examples and comparative examples

As can be seen from the comparison between examples 1-4 and comparative example 1 in Table 1, the liquid polyol product prepared by the invention can be used for bonding rigid materials, and compared with the common liquid polyester polyol sold in the market, the bonding effect (tensile shear strength) of the liquid polyol product can meet the bonding requirement between common metal materials, thereby providing a thought for the high-value utilization of HAA byproducts.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.