Bio-based cross-linking agent for textile waterproofing as well as preparation method and application of bio-based cross-linking agent

Abstract

The invention discloses a preparation method of a bio-based cross-linking agent for textile waterproofing, which comprises the following steps: 1) adding isocyanate and a sealing agent into a clean four-neck flask, and carrying out prepolymerization reaction at the temperature of 90-125 DEG C; (2) adding a solvent into a system after the reaction in the step (1) is completed, cooling to 70-95 DEG C, adding a chain extender and a hydrophilic group, and carrying out heat preservation reaction for 2-3 hours to carry out chain extension reaction; 3) after the chain extension reaction in the step 2) is completed, adding a catalyst, further reacting for 2-4 hours at the temperature of 95-120 DEG C, then cooling to 60 + / -5 DEG C, selectively adding acid to neutralize the system, and controlling the neutralization degree to be 0.85-1.1 of the mole number of cations; (4) deionized water is added for high-speed dispersion and emulsification until no precipitate exists, and the isocyanate is pentamethylene diisocyanate trimer. The obtained cross-linking agent is environmentally friendly while the waterproof performance is ensured.

Description

Technical Field

[0001] The invention relates to the field of bio-based cross-linking agents for textiles, in particular to a bio-based cross-linking agent for textile waterproofing and a preparation method and application thereof. Background Art

[0002] In textile waterproofing, the commonly used crosslinking agents are hexamethylene diisocyanate HDI, isophorone diisocyanate IPDI, or toluene diisocyanate TDI type blocked. These substances are all petroleum-based and are not environmentally friendly.

[0003] 1,5-Pentamethylenediisocyanate (PDI) is an aliphatic material that resists yellowing. Its structure is similar to that of HDI, and its carbon content is higher. Therefore, it has the potential to replace HDI downstream products in terms of structure. Moreover, the raw material PDA (pentamethylenediamine) of PDI products is prepared by biological methods, which has the advantages of low cost and renewable raw materials. It can also get rid of import restrictions and achieve both economic and environmental improvements. Summary of the invention

[0004] The object of the present invention is to provide a method for preparing a bio-based cross-linking agent for textile waterproofing, so as to solve the problems raised in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solution: a method for preparing a bio-based cross-linking agent for textile waterproofing, comprising the following steps:

[0006] 1) Add isocyanate and blocking agent into a clean four-necked flask and carry out prepolymerization at a temperature of 90-125°C;

[0007] 2) adding a solvent to the system after the reaction in step 1), cooling the system to 70-95° C., adding a chain extender and a hydrophilic group, and keeping the temperature for 2-3 hours to carry out a chain extension reaction;

[0008] 3) After the chain extension reaction in step 2) is completed, a catalyst is added, and the reaction is further carried out at a temperature of 95-120° C. for 2-4 hours, and then the temperature is lowered to 60±5° C., and an acid is selectively added to neutralize the system, and the degree of neutralization is controlled between 0.85-1.1 of the molar number of the cation;

[0009] 4) Add deionized water for high-speed dispersion and emulsification until there is no precipitation.

[0010] The isocyanate is pentamethylene diisocyanate trimer, and the isocyanate, the blocking agent, the chain extender and the hydrophilic group are added in a molar ratio of 1: (0.5-0.95): (0.05-0.5): (0.05-0.5).

[0011] As a specific implementation, the blocking agent is selected from one or more of methyl ethyl ketone oxime, imidazole, pyrazole, phenol, sodium bisulfite or caprolactam. Preferably, the blocking agent is caprolactam.

[0012] As a specific implementation manner, the solvent is selected from one or more of methyl pyrrolidone, dimethylformamide, dimethylacetamide, and acetone.

[0013] As a specific implementation, the chain extender is selected from one or more of ethanolamine, diethylene glycol, ethylene glycol, 1,4-butanediol, neopentyl glycol, and isophoronediamine.

[0014] As a specific implementation, the hydrophilic group is one or more of polyethylene glycol, N-methyldiethanolamine, and a quaternized double-terminal hydroxyl compound, and the molecular weight of the polyethylene glycol is between 300-2000.

[0015] As a specific implementation, the acid is selected from one or more of phosphoric acid, oxalic acid, acetic acid, lactic acid and citric acid.

[0016] As a specific implementation method, after slowly adding deionized water in step 4), start the dispersion disk, control the speed between 500-2000 rpm, add water while stirring until the emulsion is uniform and free of precipitation, and then filter with a 100-300 mesh filter to obtain the desired product.

[0017] The second object of the present invention is to provide a bio-based cross-linking agent for textile waterproofing, which is prepared by the above preparation method.

[0018] The third object of the present invention is to provide an application of a bio-based cross-linking agent for textile waterproofing on textile fabrics, wherein the bio-based cross-linking agent for textile waterproofing is prepared by the preparation method of the bio-based cross-linking agent for textile waterproofing.

[0019] As a specific implementation method, the specific process is as follows: the emulsion of the bio-based cross-linking agent for textile waterproofing is evenly mixed with the emulsion of the fluorine-free waterproofing agent, and the textile fabric is impregnated and rolled by a rolling method with a rolling concentration of 30-60g / L, and then placed in a 105°C oven for drying, and then dried and shaped in a high-temperature setting machine at 150°C for 90 seconds.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: the bio-based crosslinking agent for textile waterproofing of the present invention adopts the bio-based material PDI trimer as the main raw material, introduces hydrophilic groups, and then temporarily blocks some active groups to form a metastable emulsion. When used downstream, it is slightly heated to activate the active groups to be released, and cross-link with hydroxyl groups, active hydrogen, etc. in the waterproofing agent to improve the waterproof grade. DETAILED DESCRIPTION

[0021] Unless the context clearly dictates otherwise, unmodified nouns and nouns modified by "the" include singular and plural referents.

[0022] As used in the specification and claims, the terms "comprises," "comprising," "having," "may," "containing," and variations thereof as used herein refer to open transitional phrases, terms, or words that require the presence of specified ingredients / steps and allow for the presence of other ingredients / steps. However, such descriptions should be interpreted as also describing compositions or methods as "consisting of" and "consisting essentially of" the recited ingredients / steps, which allows for the presence of only the specified ingredients / steps and any unavoidable impurities that may result therefrom, and excludes other ingredients / steps.

[0023] Numerical values ​​in the specification and claims of this application should be understood to include the same numerical values ​​when reduced to the same number of significant figures and numerical values ​​that differ from the stated value by less than the experimental error of ordinary measurement techniques of the type described in this application for determining the stated value.

[0024] All ranges disclosed herein are inclusive of the indicated endpoints and are independently combinable (eg, the range of "2 grams to 10 grams" includes the endpoints 2 grams and 10 grams, and all intermediate values).

[0025] The terms "about" and "approximately" can be used to include any numerical value that can be varied without changing the basic function of the value. When used with a range, "about" and "approximately" also disclose the range defined by the absolute values ​​of the two endpoints, for example, "about 2 to about 4" also discloses a range of "2 to 4". Generally, the terms "about" and "approximately" can refer to ±10% of the indicated number. However, for temperature, the term "approximately" refers to ±1°C.

[0026] Unless expressly stated otherwise, the percentages of elements are to be considered as percentages by weight of the alloy in question.

[0027] The present disclosure may refer to the temperature of certain method steps. It should be noted that these specifications generally refer to the temperature set by the heat source (such as a furnace), and not necessarily the temperature that the heated material must reach.

[0028] The present invention provides a method for preparing a bio-based cross-linking agent for textile waterproofing, comprising the following steps:

[0029] 1) Add isocyanate and blocking agent into a clean four-necked flask, and carry out prepolymerization at a temperature of 90-125° C. This step is carried out in a solvent-free state;

[0030] 2) adding a solvent to the system after the reaction in step 1), cooling the system to 70-95° C., adding a chain extender and a hydrophilic group, and keeping the temperature for 2-3 hours to carry out a chain extension reaction;

[0031] 3) After the chain extension reaction in step 2) is completed, a catalyst is added, and the reaction is further carried out at a temperature of 95-120° C. for 2-4 hours, and then the temperature is lowered to 60±5° C., and an acid is selectively added to neutralize the system, and the degree of neutralization is controlled between 0.85-1.1 of the molar number of the cation;

[0032] 4) Slowly add deionized water, start the dispersion disk, control the speed between 500-2000 rpm, stir while adding water until the emulsion is uniform and free of precipitation, and then filter with a 100-300 mesh filter to obtain the desired product.

[0033] Here, deionized water is added to control the solid content of the emulsion to be between 40±5%.

[0034] The isocyanate is pentamethylene diisocyanate trimer, and the isocyanate, blocking agent, chain extender and hydrophilic group are added in a molar ratio of 1: (0.5-0.95): (0.05-0.5): (0.05-0.5). Here, steps 2) to 4) are carried out in the presence of a solvent.

[0035] Here, the blocking agent is selected from one or more of methyl ethyl ketone oxime, imidazole, pyrazole, phenol, sodium bisulfite or caprolactam; the solvent is selected from one or more of methyl pyrrolidone, dimethylformamide, dimethylacetamide, and acetone; the chain extender is selected from one or more of ethanolamine, diethylene glycol, ethylene glycol, 1,4-butanediol, neopentyl glycol, and isophoronediamine; the hydrophilic group is one or more of polyethylene glycol, N-methyldiethanolamine, and quaternized double-terminal hydroxyl compounds, and the molecular weight of the polyethylene glycol is between 300 and 2000; the acid is selected from one or more of phosphoric acid, oxalic acid, acetic acid, lactic acid, and citric acid.

[0036] Example 1

[0037] For non-ionic system, add 100g of bio-based isocyanate PDI trimer to a clean 500ml four-necked flask, slowly add 12.4g of caprolactam while stirring, keep the temperature at 95-100℃ for reaction for 2 hours, add 30g of solvent acetone, cool to 70-75℃, add 2.5g of chain extender 1,4-butanediol, 25g of hydrophilic group polyethylene glycol 500, keep the temperature for 2 hours, use infrared detection NCO ≤ 0.1%, add 0.1g of catalyst tetraisobutyl titanate, raise the temperature to 120℃, keep for 2 hours, cool to 60℃, then transfer to a high-speed dispersion cup, start the dispersion disk, rotate at 1000 rpm, slowly add 200g of deionized water until phase inversion occurs, the emulsion is milky white with blue light, and filter out the material after standing for 12 hours.

[0038] Example 2

[0039] Cationic system, in a clean 500 ml four-necked flask, add 100g of bio-based isocyanate PDI trimer, slowly add 12.5g of blocking agent caprolactam while stirring, keep the temperature at 95-100℃ for reaction for 2 hours, add 30g of solvent acetone, cool to 70-75℃, then add 3.3g of cationic hydrophilic chain extender N-methyldiethanolamine, and 0.1g of catalyst tetraisobutyl titanate, raise the temperature to 110℃, keep for 3 hours, cool to 60℃, add 2.5g of citric acid for neutralization, then transfer to a high-speed dispersion cup, start the dispersion disk, rotate at 1000 rpm, slowly add 182g of deionized water, until phase inversion occurs, the emulsion is milky white with blue light, and filter out the material after standing for 12 hours.

[0040] Comparative Example 1

[0041] For non-ionic system, add 100g bio-based isocyanate HDI trimer to a clean 500ml four-necked flask, slowly add 12.4g caprolactam while stirring, keep the temperature at about 100℃ for reaction for 2 hours, add 30g solvent acetone, cool to about 75℃, add 2.5g chain extender 1,4-butanediol, 25g hydrophilic group polyethylene glycol 500, keep the temperature for 2 hours, use infrared detection NCO ≤ 0.1%, add 0.1g catalyst tetraisobutyl titanate, raise the temperature to about 120℃, keep for 2 hours, cool to 60℃, then transfer to a high-speed dispersion cup, start the dispersion disk, rotate at 1000 rpm, slowly add 200g deionized water until phase inversion occurs, the emulsion is milky white with blue light, and filter out the material after standing for 12 hours.

[0042] Comparative Example 2

[0043] Cationic system, in a clean 500 ml four-necked flask, add 100g of bio-based isocyanate HDI trimer, slowly add 12.5g of blocking agent caprolactam while stirring, keep the temperature at about 100℃ for reaction for 2 hours, add 30g of solvent acetone, cool to about 75℃, then add 3.3g of cationic hydrophilic chain extender N-methyldiethanolamine, and 0.1g of catalyst tetraisobutyl titanate, raise the temperature to about 110℃, keep for 3 hours, cool to 60℃, add 2.5g of citric acid for neutralization, then transfer to a high-speed dispersion cup, start the dispersion disk, rotate at 1000 rpm, slowly add 182g of deionized water, until phase inversion occurs, the emulsion is milky white with blue light, and filter out the material after standing for 12 hours.

[0044] The dosage of each component in Examples 1 and 2 and Comparative Examples 1 and 2 is shown in Table 1, in g.

[0045] raw material Example 1 Example 2 Comparative Example 1 Comparative Example 2 PDI trimer 100 100 0 0 HDI trimer 0 0 100 100 Caprolactam 12.4 12.5 12.4 12.5 Polyethylene glycol 500 25 0 25 0 Butanediol 2.5 2.5 2.5 2.5 acetone 30 30 30 30 Cationic hydrophilic agent 0 3.3 0 3.3 catalyst 0.1 0.1 0.1 0.1 acid 0 2.5 0 2.5 Deionized water 200 182 200 182

[0046] In Examples 1 and 2, bio-based PDI trimer was used as the main raw material, and the cross-linking agent was synthesized by non-ionic and cationic methods; in Comparative Examples 1 and 2, petroleum-based HDI trimer was used as the main raw material, and the cross-linking agent was synthesized by non-ionic and cationic methods; the final solid content was controlled to about 40%, and the particle size distribution gradually changed from about 100 nanometers to about 230 nanometers through observation by Malvern particle size analyzer, and the emulsion had a milky white and stable appearance.

[0047] The cross-linking agent obtained in the above-mentioned Examples 1 and 2 and Comparative Examples 1 and 2 was used to treat the textile fabric. Specifically, the fluorine-free waterproofing agent RH-NB-SF16 of Zhejiang Runhe was used, and about 10% of the cross-linking agent obtained in Examples 1 and 2 and Comparative Examples 1 and 2 were added respectively. The fabric used was polyester, 50 g / L working solution, the fabric was impregnated and rolled, and then placed in a 105°C oven for drying, and then dried and shaped at 150°C for 90 seconds on a high-temperature setting machine.

[0048] The following properties of the treated fabrics were tested, and the test data are shown in Table 2:

[0049] Salt resistance and alkali resistance are evaluated according to industry standards: 20g / L solution + salt or alkali;

[0050] Anti-stick roller method test: 50g / L working solution + 1g / L dye, observe the time and amount of adhesion after shaking;

[0051] The fabric waterproof test is carried out in accordance with GB / T4745-2012.

[0052] Table 2

[0053] Waterproof grade Salt resistance and stability Alkali resistance stability Anti-stick roller Example 1 Level 4 50 degrees 60 degree wall sticking Trace Example 2 Level 4 48 degrees 50 degrees sticky wall Small amount Comparative Example 1 Level 3 50 degrees 60 degree wall sticking Trace Comparative Example 2 Level 4 47 degrees 49 degrees sticky wall Small amount No crosslinking agent Level 1 48 degrees 50 degrees sticky wall Trace

[0054] From Table 2, we can see that the bio-based waterproof crosslinking agents synthesized by non-ionic and cationic materials have similar waterproof grades, salt resistance, alkali resistance and processing anti-sticking roller properties compared with petroleum-based raw materials, and can fully meet the replacement of waterproof crosslinking; and compared with the blank without adding crosslinking agent, the waterproof grade can be significantly improved without affecting the stability, indicating that the present invention has good functions.

[0055] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a bio-based crosslinking agent for textile waterproofing, characterized in that: The following steps are involved: 1) Add isocyanate and blocking agent into a clean four-necked flask and carry out prepolymerization at a temperature of 90-125°C; 2) Adding solvent to the system after the reaction in step 1), cooling to 70-95°C, adding chain extender and hydrophilic group, and keeping the temperature for 2-3h to carry out chain extension reaction; 3) After the chain extension reaction in step 2) is completed, a catalyst is added, and the reaction is further carried out at a temperature of 95-120°C for 2-4 hours, and then the temperature is lowered to 60±5°C, and an acid is selectively added to neutralize the system, and the degree of neutralization is controlled between 0.85-1.1 of the molar number of the cation; 4) Add deionized water for high-speed dispersion and emulsification until there is no precipitation. Wherein, the isocyanate is pentamethylene diisocyanate trimer, and the isocyanate, the blocking agent, the chain extender and the hydrophilic group are added in a molar ratio of 1: (0.5-0.95): (0.05-0.5): (0.05-0.5).

2. The method for preparing a bio-based crosslinking agent for textile waterproofing according to claim 1, characterized in that: The blocking agent is selected from one or more of methyl ethyl ketone oxime, imidazole, pyrazole, phenol, sodium bisulfite or caprolactam.

3. The method for preparing a bio-based crosslinking agent for textile waterproofing according to claim 1, characterized in that: The solvent is selected from one or more of methyl pyrrolidone, dimethylformamide, dimethylacetamide and acetone.

4. The method for preparing a bio-based cross-linking agent for textile waterproofing according to claim 1, characterized in that: The chain extender is selected from one or more of ethanolamine, diethylene glycol, ethylene glycol, 1,4-butanediol, neopentyl glycol, and isophoronediamine.

5. The method for preparing a bio-based cross-linking agent for textile waterproofing according to claim 1, characterized in that: The hydrophilic group is one or more of polyethylene glycol, N-methyldiethanolamine, and quaternized double-terminal hydroxyl compounds, and the molecular weight of the polyethylene glycol is between 300 and 2000.

6. The method for preparing a bio-based cross-linking agent for textile waterproofing according to claim 1, characterized in that: The acid is selected from one or more of phosphoric acid, oxalic acid, acetic acid, lactic acid and citric acid.

7. The method for preparing a bio-based crosslinking agent for textile waterproofing according to claim 1, characterized in that: In step 4), after slowly adding deionized water, start the dispersion disk and control the speed between 500-2000 rpm. Stir while adding water until the emulsion is uniform and free of precipitation. Then filter with a 100-300 mesh filter to obtain the desired product.

8. A bio-based cross-linking agent for textile waterproofing obtained by the preparation method according to any one of claims 1 to 7.

9. Use of a bio-based cross-linking agent for textile waterproofing obtained by the preparation method according to any one of claims 1 to 7 on textile fabrics.

10. The use of a bio-based cross-linking agent for textile waterproofing on textile fabrics according to claim 9, characterized in that: The specific process is as follows: the emulsion of the bio-based cross-linking agent for textile waterproofing is evenly mixed with the emulsion of the fluorine-free waterproofing agent, and the textile fabric is impregnated and rolled by a rolling method with a rolling concentration of 30-60g / L, and then placed in a 105°C oven for drying, and then dried and set in a high-temperature setting machine at 150°C for 90 seconds.