阅读说明：本技术 一种室温自修复材料及其制备方法 (Room-temperature self-repairing material and preparation method thereof ) 是由 汤杰 于 2019-10-04 设计创作，主要内容包括：本发明属于新材料领域。本发明涉及一种室温自修复材料及其制备方法,该方法以含氢硅氧烷、环氧树脂、二元胺为原料,分别经过硅氢加成反应、环氧树脂开环反应以及氧化反应多步骤反应完成,通过分子结构设计,调整聚合物结构以及优化聚合工艺,合成了一种室温自修复聚硫氨酯材料,并配制成室温自修复清漆。该复合材料不仅有效解决目前自修复材料修复率低、修复次数有限或需要借助外加能量或者愈合剂等手段的不足,同时兼具疏水抗污的效用,可大大拓宽其应用领域。(The invention belongs to the field of new materials. The invention relates to a room temperature self-repairing material and a preparation method thereof, the method takes hydrogen-containing siloxane, epoxy resin and diamine as raw materials, the raw materials are respectively subjected to hydrosilylation reaction, epoxy resin ring-opening reaction and oxidation reaction multi-step reaction, a polymer structure is adjusted and a polymerization process is optimized through molecular structure design, and the room temperature self-repairing polythiourethane material is synthesized and is prepared into room temperature self-repairing varnish. The composite material not only effectively overcomes the defects of low repair rate, limited repair times or the need of means such as external energy or a healing agent and the like of the existing self-repairing material, but also has the hydrophobic and anti-fouling effects, and can greatly widen the application field of the composite material.)

1. The room temperature self-repairing material is characterized by having a structural formula as follows:

2. The room temperature self-repairing material as claimed in claim 1, wherein R ₁ is any one of butyl, cyclohexyl, ethyl and hexyl, x is 10-20, and n is 50-100.

3. the preparation method of the room temperature self-repairing material is characterized by comprising the following steps: all expressed as mole fraction of reactive functional groups

Step 1): carrying out hydrosilylation reaction to obtain siloxane modified epoxy monomer marked as A;

Step 2): reacting siloxane modified epoxy monomer A with carbon disulfide to obtain siloxane-containing five-membered thiocarbonate, which is marked as B;

step 3): reacting the epoxy resin with carbon disulfide to obtain five-membered thiocarbonate which is marked as C;

step 4): ring-opening reaction of pentabasic thiocarbonate C and diamine to obtain amino-terminated polythiourethane, which is marked as D;

Step 5): b and D react with ring opening, get siloxane modified polythiourethane, mark as E;

Step 6): and E, carrying out oxidation reaction to obtain self-repairing polythiourethane, and marking as F.

4. the preparation method of the room temperature self-repairing material as claimed in claim 3, characterized in that: the step 1) is specifically as follows:

dissolving 1 part of hydrogen-containing siloxane at one end in 50 parts of tetrahydrofuran, dissolving 1.0-1.1 parts of glycidyl methacrylate, 1 wt% of hydroquinone and 10 ^-5 parts of catalyst a in 10 parts of tetrahydrofuran, adding into a constant-pressure dropping funnel, controlling the dropping speed, stirring, reacting at 60-120 ℃ for 3-5h, distilling under reduced pressure to remove the solvent, adding 30 parts of toluene, excessive sodium bicarbonate and 10 parts of deionized water, stirring at 60 ℃ for 3h, separating a water phase, taking an organic layer, and distilling under reduced pressure to remove the solvent to obtain a siloxane epoxy monomer A;

the dosage of the hydroquinone is 1 wt% of the mass of the glycidyl methacrylate;

The catalyst a is chloroplatinic acid, carbine, platinum dioxide or aluminum trichloride.

5. The preparation method of the room temperature self-repairing material as claimed in claim 3, characterized in that: the step 2) is specifically as follows:

dissolving 1 part of A, 2-4% of catalyst B and 1-1.2 parts of carbon disulfide in 40 parts of organic solvent a, carrying out ice bath, stirring for 2 hours, stirring for 4-24 hours at room temperature, carrying out reduced pressure distillation and concentration, adding 30 parts of deionized water, oscillating, adding 40 parts of organic solvent B, extracting, separating liquid, drying with anhydrous sodium sulfate, and filtering to obtain a yellow product solution, which is marked as B;

The amount of the catalyst is 2-4% of the mole number of A.

6. the preparation method of the room temperature self-repairing material as claimed in claim 3, characterized in that: the step 3) is specifically as follows:

dissolving 1 part of epoxy resin, 2-4% of catalyst b and 1-1.2 parts of carbon disulfide in 40 parts of organic solvent a, carrying out ice bath, stirring for 2 hours, stirring for 4-24 hours at room temperature, carrying out reduced pressure distillation and concentration, adding 30 parts of deionized water, oscillating, adding 40 parts of organic solvent b, extracting, separating liquid, drying with anhydrous sodium sulfate, and filtering to obtain a yellow product solution, wherein the yellow product solution is marked as C;

the dosage of the catalyst is 2-4% of the mole number of A;

the epoxy resin is 6101, 711, CY-183 or 6269.

7. the preparation method of the room temperature self-repairing material as claimed in claim 3, characterized in that: the step 4) is specifically as follows:

And adding 1.2-1.4 parts of diamine into 1 part of C, stirring at room temperature for 0.5-2h, carrying out reduced pressure distillation, and purifying to obtain a yellow product which is marked as D.

8. the preparation method of the room temperature self-repairing material as claimed in claim 3, characterized in that: the step 5) is specifically as follows:

to 1 part of D is added 1.0 to 1.2 parts of B and stirred at room temperature for 0.5 to 2 hours, distilled under reduced pressure and dried in vacuo to give a yellow product, noted E.

9. The preparation method of the room temperature self-repairing material as claimed in claim 3, characterized in that: the step 6) is specifically as follows:

pouring 1 part of E into a beaker, adding 1 part of 30% hydrogen peroxide solution and 1-5% of catalyst b to generate a crosslinked yellow elastomer; adding saturated sodium thiosulfate aqueous solution, stirring until the yellow color disappears, filtering, and drying to obtain a self-repairing material, which is marked as F;

The dosage of the catalyst b is 1 to 5 percent of the mole number of C.

10. the preparation method of the room temperature self-repairing material as claimed in claim 5 or 6, characterized in that: the organic solvent a is tetrahydrofuran, acetone, acetonitrile or methanol; the organic solvent b is ethyl acetate, hexane or chloroform, and the catalyst b is sodium iodide, lithium bromide or lithium chloride.

Technical Field

the invention relates to a room temperature self-repairing material and a preparation method thereof. The invention belongs to the field of new materials.

Background

polyurethanes refer to a class of polymers containing a large number of urethanes in the molecular structure, also known as polyurethanes, abbreviated by PU. Because the performance of the polyurethane material can be realized by adjusting the molecular structure of the polyurethane material, and the method is simple and convenient, the application of the polyurethane material is spread in 5 fields of high polymer material coatings, plastics, rubbers, fibers and adhesives, and the polyurethane material is widely applied to the industries of buildings, automobiles, electronics, packaging, clothing, shoe making and the like.

Polythiourethanes combine the properties of both polythios and polyurethanes. The polythiourethane material is commonly used in hydrogel, airport runways, sealant and the like, and inevitably damaged by external force to generate defects in the actual use process, cause the loss or reduction of the related performance, shorten the service life of the material, reduce the safety of the material and increase the maintenance cost of the material. However, most of the materials used at present cannot be repaired after the defects are generated, and some materials can be repaired, but the repairing process needs additional healing agents or the input of energy (such as heating, illumination, pressure and the like) or the repairing times are limited, which greatly limits the practical use requirements. In addition, there are few reported materials that can spontaneously self-repair at room temperature (without the need for additional healing agents or energy), and some self-repairs are also conditioned by compromising mechanical properties, and are accompanied by problems of high preparation cost, complex synthesis process, and the like. Therefore, the preparation of the material with self-repairing function and excellent mechanical property has important significance.

Disclosure of Invention

The invention aims to overcome the defects of low self-repairing rate, limited repairing times or the need of means such as external energy or a healing agent in the prior art, and provides a room-temperature self-repairing polythiourethane material and a preparation method thereof.

the technical scheme adopted by the invention for solving the technical problems is as follows:

The room temperature self-repairing material has the following structural formula:

preferably, the room temperature self-repairing material is characterized in that R ₁ is any one of butyl, cyclohexyl, ethyl and hexyl, x is 10-20, and n is 50-100.

a preparation method of a room temperature self-repairing material comprises the following steps:

step 1): carrying out hydrosilylation reaction to obtain siloxane modified epoxy monomer marked as A;

Step 2): reacting siloxane modified epoxy monomer A with carbon disulfide to obtain siloxane-containing five-membered thiocarbonate, which is marked as B;

Step 3): reacting the epoxy resin with carbon disulfide to obtain five-membered thiocarbonate which is marked as C;

Step 4): ring-opening reaction of pentabasic thiocarbonate C and diamine to obtain amino-terminated polythiourethane, which is marked as D;

step 5): b and D react with ring opening, get siloxane modified polythiourethane, mark as E;

Step 6): and E, carrying out oxidation reaction to obtain self-repairing polythiourethane, and marking as F.

all expressed as mole fraction of reactive functional groups

Preferably, the step 1) is specifically:

Dissolving 1 part of hydrogen-containing siloxane at one end in 50 parts of tetrahydrofuran, dissolving 1.0-1.1 parts of glycidyl methacrylate, 1 wt% of hydroquinone and 10 ^-5 parts of catalyst a in 10 parts of tetrahydrofuran, adding into a constant-pressure dropping funnel, controlling the dropping speed, stirring, reacting at 60-120 ℃ for 3-5h, distilling under reduced pressure to remove the solvent, adding 30 parts of toluene, excessive sodium bicarbonate and 10 parts of deionized water, stirring at 60 ℃ for 3h, separating a water phase, taking an organic layer, and distilling under reduced pressure to remove the solvent to obtain a siloxane epoxy monomer A;

the content of hydroquinone is 1 wt% of the mass of the glycidyl methacrylate.

Preferably, the step 2) is specifically:

dissolving 1 part of A, 2-4% of catalyst B and 1-1.2 parts of carbon disulfide in 40 parts of organic solvent a, carrying out ice bath, stirring for 2 hours, stirring for 4-24 hours at room temperature, carrying out reduced pressure distillation and concentration, adding 30 parts of deionized water, oscillating, adding 40 parts of organic solvent B, extracting, separating liquid, drying with anhydrous sodium sulfate, and filtering to obtain a yellow product solution, which is marked as B;

The amount of the catalyst is 2-4% of the mole number of A.

Preferably, the step 3) is specifically:

dissolving 1 part of epoxy resin, 2-4% of catalyst b and 1-1.2 parts of carbon disulfide in 40 parts of organic solvent a, carrying out ice bath, stirring for 2 hours, stirring for 4-24 hours at room temperature, carrying out reduced pressure distillation and concentration, adding 30 parts of deionized water, oscillating, adding 40 parts of organic solvent b, extracting, separating liquid, drying with anhydrous sodium sulfate, and filtering to obtain a yellow product solution, wherein the yellow product solution is marked as C;

the amount of the catalyst is 2-4% of the mole number of A.

Preferably, the step 4) is specifically:

And adding 1.2-1.4 parts of diamine into 1 part of C, stirring at room temperature for 0.5-2h, carrying out reduced pressure distillation, and purifying to obtain a yellow product which is marked as D.

Preferably, the step 5) is specifically:

To 1 part of D is added 1.0 to 1.2 parts of B and stirred at room temperature for 0.5 to 2 hours, distilled under reduced pressure and dried in vacuo to give a yellow product, noted E.

preferably, the step 6) is specifically:

Pouring 1 part of E into a beaker, adding 1 part of 30% hydrogen peroxide solution and 1-5% of catalyst b to generate a crosslinked yellow elastomer; adding saturated sodium thiosulfate aqueous solution, stirring until the yellow color disappears, filtering, and drying to obtain a self-repairing material, which is marked as F;

The dosage of the catalyst b is 1 to 5 percent of the mole number of C.

preferably, the catalyst a is chloroplatinic acid, carbene alkane, platinum dioxide or aluminum trichloride.

preferably, the organic solvent a is tetrahydrofuran, acetone, acetonitrile, methanol; the organic solvent b is ethyl acetate, hexane or chloroform.

preferably, the catalyst b is sodium iodide, lithium bromide or lithium chloride.

Preferably, the epoxy resin is 6101, 711, CY-183 or 6269.

the room temperature self-repairing material varnish is prepared from the following raw materials in parts by weight: f50-90 parts and a crosslinking component 10-50 parts;

the crosslinking component comprises the following components in percentage by weight: 620253-57 parts of aliphatic polyether type polyurethane diacrylate, 15 parts of TMPTA, 15 parts of TPGDA, 12 parts of butyl acrylate and 1-5 parts of PI.

preferably, the photoinitiator PI is BP, ITX, CBP, MK, DEMK, MEMK.

Preferably, the preparation method comprises the following steps: the self-repairing varnish is prepared by mixing the raw materials in parts by weight, coating the mixture on tinplate, and irradiating the mixture for 0.5 to 5 minutes under UV light.

The room temperature self-repairing material provided by the invention has the following preparation process:

the invention has the beneficial effects that:

(1) the invention provides a material capable of self-repairing at room temperature, which is prepared by adjusting a polymer structure through molecular design and adopting epoxy resin, carbon disulfide, diamine and the like as raw materials, so that the defect of insufficient single performance of the traditional polyurethane or polysulfide material is overcome, and the material has the performance advantages of wear resistance, tear resistance and high strength of polysulfide of polyurethane.

(2) The invention provides a preparation method of a room temperature self-repairing material, which adopts polyfunctional epoxy resin and diamine, designs that molecular chains contain heteroatoms such as N, O and the like, and has an average molecular weight of 8-12 kDa. Firstly, the molecular weight is too low, so that the cross-linking density is too high, the molecular chain movement is hindered, and a good self-repairing rate cannot be reflected; secondly, too high molecular weight leads to too low crosslinking density and to unsatisfactory mechanical properties; thirdly, the polymer contains single bonds formed by heteroatoms such as N, O, and the molecular chain has better flexibility.

(3) the invention provides a preparation method of a room temperature self-repairing material, which adopts hydrogen-containing siloxane end-capped polythiourethane. Firstly, silicon atoms have low surface tension and migrate to the surface and are positioned at the end group of a molecular chain, so that the silicon atoms are easier to migrate, and the silicon-oxygen bond has longer bond length and larger silicon-oxygen-silicon bond angle, so that the molecular chain is very soft, the movement of the molecular chain is facilitated, and the dual functions are beneficial to self-repair; secondly, the bond energy of silicon-oxygen bonds in siloxane is very large, so that the thermal stability of the siloxane is superior to that of the conventional material, and the service life of the siloxane can be prolonged when the siloxane is used outdoors; finally, the siloxane which migrates to the surface of the material has a larger water contact angle and has the function of resisting pollution.

(4) The invention provides a preparation method of a room temperature self-repairing material, which adjusts a polymer structure through molecular design, ensures low crosslinking density by using a terminal group reactant to ensure the movement of a molecular chain segment, ensures that hetero atoms such as N, O and the like on a molecular chain can form a hydrogen bond, and can form a certain repairing rate at the beginning by adding the weak hydrogen bond force of S-H.

(5) The invention provides a room temperature self-repairing material, which is characterized in that a polymer structure is adjusted through molecular design, a disulfide bond is used as a reversible chemical bond, the defects that an additional means is needed or the repairing rate is low and the repairing frequency is limited in the existing self-repairing material are overcome, the material can be self-repaired at room temperature, and meanwhile, the repairing rate is high and the repairing frequency is not limited. It is anticipated that this material will appeal to a wide market space.

The specific implementation mode is as follows:

The present invention will be described in detail with reference to examples. It is to be understood, however, that the following examples are illustrative of embodiments of the present invention and are not to be construed as limiting the scope of the invention.