CN111533939A

CN111533939A - Self-healing safety tire

Info

Publication number: CN111533939A
Application number: CN202010468718.9A
Authority: CN
Inventors: 蒋凯
Original assignee: Wuxi I Reach Technology Co ltd
Current assignee: Wuxi I Reach Technology Co ltd
Priority date: 2020-05-28
Filing date: 2020-05-28
Publication date: 2020-08-14

Abstract

A self-healing safety tire comprises a tire and a film forming substance which is prepared by using a polyester waterborne polyurethane-polyurea dispersion liquid and wood pulp and the like as an auxiliary, wherein the film forming substance is coated on a tire inner liner layer as a tire explosion-proof coating. The aqueous polyurethane-polyurea dispersion liquid, namely the film forming substance, is an aqueous polyurethane-polyurea dispersion: comprises polymer polyol which is 250-310 parts of adipic acid mixed polyol ester, 40-80 parts of isocyanate, polyisocyanate with isocyanate group functionality more than or equal to 2, and the isocyanate is TDI, tetramethylene diisocyanate, Hexamethylene Diisocyanate (HDI) and isophorone diisocyanate (IPDI); then adding a solution consisting of 2-4 parts of ethylenediamine, 55-80 parts of 2- (2-aminoethylamino) sodium ethanesulfonate and water; stirring to obtain stable polyurethane-polyurea dispersion liquid. The PUR dispersions are stable, storable and transportable coatings with very good wet adhesive strength.

Description

Self-healing safety tire

Technical Field

The invention relates to the field of tire manufacturing, in particular to a self-healing or self-repairing safety tire, and relates to application of a tire explosion-proof liquid coating to form an explosion-proof membrane on a tire and a preparation method thereof. In particular to a polymer coating agent applied to a tire and a preparation method thereof.

Background

The automobile enters a family, the tire is an essential component of the automobile, the common tire is a pressure-bearing tire, and the tire is basically scrapped when the tire is inadvertently punctured or blown out due to pinning or sand holes during driving, and particularly, the tire is punctured on a highway to cause a great risk. The main component of the prior tire repair material is glue, and the prior tire repair material has the defects of low strength, easy repeated damage and incomplete repair. The tire explosion-proof coating is a polymer liquid coated on the inner layer of the inner tube, the punctured tire does not need to be repaired and replaced, the tire explosion-proof liquid automatically leaks the leakage, the air leakage problem caused by the pricking of the tire surface can be effectively avoided, the tire explosion-proof and leakage-proof capacity is improved, the risk of tire burst is reduced, and the service life of the tire is prolonged. Tire burst protection polymer fluids may also be used specifically for tire repair.

The self-healing or self-repairing safety tire can greatly enhance the safety of the tire, and CN 104109456B relates to a single-component tire explosion-proof liquid and a preparation method thereof, and discloses the self-healing or self-repairing safety tire which comprises the following raw materials in parts by weight: 41-63 parts of waterborne polyurethane, 18.2-29 parts of polyether 220, 6-9.5 parts of toluene diisocyanate, 10-15.5 parts of plasticizer, 1-3.4 parts of pH stabilizer, 0.5-1 part of dispersant, 0.5-1 part of film-forming assistant and 0.1-0.3 part of defoaming agent.

However, in general, the prior art, including the major tire burst protection fluids currently on the market, suffer from weak adhesion, poor long-term durability, poor water resistance, and corrosion of the (inner) outer tire. Particularly, the problem of low-temperature freezing resistance is not solved, and although an antifreezing agent ethylene glycol and the like are added, the polymer film loses the effect when the environmental temperature is lower than minus 5 ℃.

Disclosure of Invention

The invention aims to provide a formula and a preparation method of an anti-explosion liquid (film) for an anti-explosion wheel, namely a self-healing or self-repairing tire, in particular to a tire.

The self-healing safety tire comprises a tire, a water-based polyurethane-polyurea dispersion liquid of polyester, wood pulp and the like which are used as auxiliary materials and used as film forming substances, wherein the film forming substances are used as a tire explosion-proof coating to be coated on an inner liner of the tire, the coated tire has excellent explosion-proof performance, and the film forming substances are solvent-free, non-toxic and non-flammable, can be used in an environment of-40 ℃ to 185 ℃, and are stable for a long time;

a water-based polyurethane-polyurea dispersion liquid, namely a film-forming substance relates to a water-based polyurethane-polyurea dispersion body, and the preparation reaction comprises the following raw material components: the polymer polyol adopts 250-310 parts of adipic acid mixed polyol ester; the mixed polyalcohol is prepared by mixing ethylene glycol, 1, 4-butanediol and diethylene glycol; adding 40-80 parts of isocyanate, polyisocyanate with isocyanate group functionality not less than 2, wherein the isocyanate is TDI, tetramethylene diisocyanate, Hexamethylene Diisocyanate (HDI) and isophorone diisocyanate (IPDI); adding 2-4 parts of diamine or polyamine (including ethylenediamine, 1, 2-and 1, 3-diaminopropane, 1, 4-diaminobutane, 1, 6-diaminohexane and isophorone diamine), 55-80 parts of 2- (2-amino ethyl amino) sodium ethanesulfonate and water to form a solution, and coating the solution on the inner surface of the tire to ensure that the tire still has self-adhesion after water is evaporated; wherein the ratio of polyol to isocyanate is controlled to control the isocyanate index R to be from 0.91 to 1.0, more preferably from 0.93 to 0.98, especially from 0.94 to 0.96. The water content is controlled to obtain a solid content of 40 and a particle size of 150-250 nm.

And adding 10-30 parts of wood pulp, and crushing to 1-3 mm, wherein the adding method comprises the following steps: adding 500 parts of deionized water, then adding 100 parts of polyurethane-polyurea dispersion liquid, 360 parts of deionized water and 10 parts of ethylene glycol, and uniformly dispersing at room temperature.

From the material texture, polyurethanes have exceptional low-temperature properties, and polyurethane-Polyurea (PUR) dispersions are distinguished, inter alia, by high resistance to chemicals and water, high mechanical strength and high tensile strength and elongation. polyurethane-Polyurea (PUR) dispersions are film-forming substances, which avoid the disadvantages of the abovementioned market varieties.

The formulations and the preparation of polyurethane-Polyurea (PUR) dispersions, in which hydrophilic groups are embedded, can be self-emulsifying, i.e.they can be dispersed in water without the aid of external emulsifiers;

by means of the incorporation of specific polyester polyols, which are synthesized predominantly from short-chain polyol components, PUR dispersions having very good elongation can be obtained. The water polyurethane-polyurea dispersoid of the specific polyester is used as a main film forming substance, wood pulp and the like are used as assistance, the formed tire explosion-proof liquid has excellent explosion-proof performance (leak plugging and self-healing) when the film is formed, the formed liquid is solvent-free, non-toxic and non-flammable, can be used in the environment of minus 40 ℃ to 185 ℃, and is stable for a long time. The inner and outer tyres are not corroded, and the diameter of a leakage hole is easily blocked by 3-5 mm.

The polyureas of the present invention are elastomeric materials formed by the reaction of an isocyanate component and an amino (hydroxy) compound component.

The preparation method of the polyurethane-polyurea dispersion liquid comprises the following steps: adipic acid was heated to 65 + -7 deg.C with mixed polyol esters (ethylene glycol, 1, 4-butanediol, and diethylene glycol mixture). Subsequently adding polyisocyanate TDI80, stirring the mixture at 100 +/-7 ℃ until the theoretical NCO content reaches 2.9, dissolving the mixture with acetone at 50 +/-5 ℃ until the acetone content is not less than that of the polyol ester, and then adding a solution consisting of ethylenediamine, sodium 2- (2-aminoethylamino) ethanesulfonate and a small amount of water; the subsequent stirring time is 20 plus or minus 12 minutes; during stirring, dispersing the product by adding water in an amount larger than that of acetone; the acetone is then removed by vacuum distillation to give a polyurethane-polyurea dispersion with a high solids content.

Diamines, polyamines and hydrazides may be used as the low molecular weight compounds that act to harden and/or branch the polymer chains. Examples include ethylenediamine, 1, 2-and 1, 3-diaminopropane, 1, 4-diaminobutane, 1, 6-diaminohexane, isophoronediamine, the latter four of which may be substituted for ethylenediamine. In the preparation of the PUR dispersions of the invention, they can be used as chain extenders and/or chain terminators.

The PUR dispersion of the present invention may optionally contain a component which is located at the end of the chain and blocks the end. These units are derived from monofunctional compounds which react with NCO groups, such as monoamines.

Ionically or potentially ionically hydrophilic compounds e comprise compounds containing at least one isocyanate-reactive group and at least one functional group, for example-COOY, -SO3Y, -po (oy)2(Y, for example, H, NH4+, metal cation), -NR 2, -NR 3+ (R ═ H, alkyl, aryl) which, upon interaction with aqueous media, enter into a pH-dependent dissociation equilibrium and can therefore carry negative, positive or neutral charges. Preferred isocyanate reactive groups are hydroxyl or amino groups.

The process for preparing the aqueous PUR dispersions of the invention can be carried out in one or more stages in a homogeneous phase or, in the case of a multistage reaction, can be carried out partly in the dispersed phase. After the addition polymerization of the components, which can be carried out completely or partially, there is a dispersing, emulsifying or dissolving step. Thereafter, optionally, further addition polymerization or modification is carried out in the dispersed phase. For the preparation of the aqueous PUR dispersions of the invention, all processes known in the art can be used, for example prepolymer mixing processes, solvent (acetone) processes or melt dispersion processes. The PUR dispersions of the invention are preferably prepared by the solvent (acetone) process.

Before, during or after dispersion in water, the remaining isocyanate groups are chain-extended or chain-terminated with amino-functional compounds, in particular sodium 2- (2-aminoethylamino) ethanesulfonate (the product containing carbamate or carbamate groups); the PUR dispersions of the invention can also be prepared by the solvent (e.g.acetone) process. To accelerate the addition reaction of the isocyanates, catalysts known from polyurethane chemistry can be used. Preference is given to dibutyltin dilaurate.

Suitable solvents include the known acetone or butanone, which can be added not only at the beginning of the preparation but also in a later part. Acetone and butanone are preferred. Other solvents include xylene, toluene, cyclohexane, butyl acetate, methoxypropyl acetate and other solvents with ether or ester units. After the preparation of the dispersion, the solvent may be distilled off in whole or in part, or may remain completely in the dispersion.

The preparation of the PUR dispersion from the prepolymer is carried out after chain extension. For this purpose, the dissolved and chain-extended polyurethane polymer is introduced into the dispersion water under strong shearing action, for example under vigorous stirring, or, conversely, the dispersion water is stirred into the prepolymer solution. Water is preferably introduced into the dissolved prepolymer.

After the dispersion step, the solvent still present in the dispersion is usually subsequently removed by distillation. It may actually be removed during the dispersion process.

The PUR dispersions of the invention are stable, storable and transportable and can be processed at any desired subsequent point in time. They can be cured and applied in a film coating at relatively low temperatures of 120 to 150 ℃ in 2 to 3 minutes, in order to obtain coatings which have in particular very good wet adhesion strength, it being of course necessary to control the R index.

Depending on the selected chemical composition and the urethane group content, coatings with different properties are obtained. Thus, soft tack coatings, thermoplastic and rubber elastic products with a variety of hardnesses up to and including glass hard thermoset materials can be obtained. The hydrophilicity of the product may also fluctuate within certain limits. If the elastomeric product is not chemically crosslinked, the thermoplastic treatment may be carried out at elevated temperatures of from 100 to 180 ℃.

Owing to their excellent elongation and high tensile strength, the PUR dispersions of the invention are particularly suitable for the formulation of tire puncture sealants and for the preparation of films on the inner surface of tires to form run flat tires.

The PUR dispersions of the invention may contain known additives, defoamers, thickeners, fillers, and such fillers may be present in the final product up to 70.

In the formula of the tire explosion-proof liquid, the PUR dispersoid is a film forming material, and the proportion range accounts for 3-30% of the total weight, can also be 5-20%, and is 10% in the embodiment. More is water.

In the formula of the tire explosion-proof liquid, fibers play a role in leaking stoppage, spandex, chinlon, polyester fibers and paper reinforcement or sawdust powder can be used, and wood pulp fibers with the length of 1-3 mm are selected.

Has the advantages that: the invention has a brand-new conception on material application, and the composition of the tire explosion-proof liquid comprises the preparation of WPU (waterborne polyurethane) and polyurethane-Polyurea (PUR), wherein 2- (2-aminoethylamino) sodium ethanesulfonate is used as an amino group and a hydrophilic dispersant; and wood pulp is also added to prepare tire explosion-proof liquid and the like. Polyurethanes have exceptional low temperature properties in material-per-se, and polyurethane-Polyurea (PUR) dispersions are distinguished, inter alia, by high resistance to chemicals and water, high mechanical strength and high tensile strength and elongation. polyurethane-Polyurea (PUR) dispersions are film-forming substances which avoid the disadvantages of the existing market varieties. The formulations and the preparation of polyurethane-Polyurea (PUR) dispersions, in which hydrophilic groups are embedded, can be self-emulsifying, i.e.they can be dispersed in water without the aid of external emulsifiers; by means of the incorporation of specific polyester polyols, which are synthesized predominantly from short-chain polyol components, PUR dispersions having very good elongation can be obtained. The tire explosion-proof liquid coating formed by the aqueous polyurethane-polyurea dispersoid of the specific polyester is used as a main film forming substance and wood pulp and the like are used as assistance, has excellent explosion-proof performance, has no solvent, no toxicity and no flammability, can be used in the environment of-40 ℃ to 185 ℃, has stable self-adhesion for a long time, and can realize self-adhesion and leakage stoppage. 20 parts of wood pulp are crushed to 1-3 mm, the size is consistent with that of the aqueous film forming system, and the plugging agent is suitable for plugging large-aperture plugging and can plug 5mm or larger aperture.

Detailed Description

The invention is further illustrated, but is not limited by the following examples in which all parts and percentages are by weight unless otherwise specified.

Example 1 polyurethane-polyurea Dispersion

280g of adipic acid mixed polyol ester (ethylene glycol, 1, 4-butanediol and diethylene glycol mixed in parts by weight: 27/40/33) (average molecular weight 2000g/mol, bifunctional OH number of about 56) were heated to 65 ℃. 43.6g of TDI80 were subsequently added in the course of 5 minutes and the mixture was stirred at 100 ℃ until the theoretical NCO content was 2.9, the mixture was dissolved with 350g of acetone at 50 ℃ and a solution of 2.4g of ethylenediamine, 15.8g of sodium 2- (2-aminoethylamino) ethanesulfonate and 63g of water was metered in the course of 5 minutes. The subsequent stirring time was 15 minutes. Thereafter, over the course of 10 minutes, the product was dispersed by adding 426g of water. The acetone was subsequently removed by vacuum distillation to give a storage-stable polyurethane-polyurea dispersion having a solids content of 40% and a particle size of 171 nm.

Has the following characteristics: shore a hardness 90; modulus at 100% ═ 2.2 MPa; tensile strength is 25 MPa; elongation at break was 400%.

Example 2: preparing tire explosion-proof liquid:

20g (parts) of wood pulp (with the water content of 8%) is crushed to 1-3 mm, 500 parts of deionized water and 10 parts of disodium hydrogen phosphate are added to soak for 48 hours, and then 100 parts of the polyurethane-polyurea dispersion liquid obtained in example 1, 360 parts of deionized water and 10 parts of ethylene glycol are added, and the mixture is uniformly dispersed at room temperature. Optionally, additives such as thickener (sodium polyacrylate or sodium carboxymethylcellulose), defoaming agent, wetting agent, leveling agent, etc. can be added.

The storage is stable, the inner and outer tyres are not corroded, and the diameter of a leak-stopping hole is easy to be 3-9 mm.

Example 3: tire explosion-proof liquid: optionally, additives such as thickener (sodium polyacrylate or sodium carboxymethylcellulose), defoaming agent (silicone oil, polyoxypropylene, etc.), wetting agent and leveling agent (polydimethylsiloxane, polymethylphenylsiloxane), etc. can be added. The storage is stable, the inner and outer tyres are not corroded, and the diameter of a leak-stopping hole is easy to be 3-5 mm.

Example 4: the application of the tire explosion-proof liquid coating to form an explosion-proof film comprises the following steps: the finished product of the film-forming substance is used as a tire explosion-proof coating to be coated on the tire inner liner, the thickness of the coating is more than 0.7 mm, and the coating is treated at the temperature of 120-130 ℃; because the amount of the tire explosion-proof liquid is more, the coating is liquid all the time, and can be added into the tire, or the heat treatment is not needed; the coated tire has excellent explosion-proof performance, and the film forming matter is solvent-free, non-toxic and non-flammable, can be used in the environment of-40 ℃ to 185 ℃, and is stable for a long time.

Claims

1. A self-healing safety tire is characterized by comprising a tire and a film forming substance which is prepared by using a polyester waterborne polyurethane-polyurea dispersion liquid and wood pulp and the like as an auxiliary, wherein the film forming substance is used as a tire explosion-proof coating and coated on a tire inner liner.

2. A self-healing run-flat tire according to claim 1, wherein the aqueous polyurethane-polyurea dispersion, i.e. the film-forming material, is an aqueous polyurethane-polyurea dispersion, and the raw material components for the preparation reaction are: the polymer polyol is prepared from 310 parts of adipic acid mixed polyol ester, 40-80 parts of isocyanate, and polyisocyanate with isocyanate group functionality not less than 2, wherein the isocyanate is TDI, tetramethylene diisocyanate, Hexamethylene Diisocyanate (HDI) or isophorone diisocyanate (IPDI); then adding solution consisting of ethylenediamine or 1, 2-and 1, 3-diaminopropane, 1, 4-diaminobutane, 1, 6-diaminohexane, 2-4 parts of isophoronediamine, 55-80 parts of 2- (2-aminoethylamino) sodium ethanesulfonate and water; stirring to obtain stable polyurethane-polyurea dispersion liquid.

3. A method for preparing the aqueous polyurethane-polyurea dispersion liquid for self-healing run-flat tires according to claim 1-2, wherein the mixed polyol of adipic acid and mixed polyol ester is a mixture of ethylene glycol, 1, 4-butanediol and diethylene glycol, and is heated to 65 ± 7 ℃; then adding polyisocyanate TDI, stirring the mixture at 100 +/-7 ℃ until the NCO content is 2.9, dissolving the mixture with acetone at 50 +/-5 ℃ until the acetone content is not less than that of the polyol ester, and then adding a solution consisting of ethylenediamine, sodium 2- (2-aminoethylamino) ethanesulfonate and a small amount of water; the subsequent stirring time is 20 plus or minus 12 minutes; during stirring, dispersing the product by adding water in an amount larger than that of acetone; acetone is then removed by vacuum distillation to yield a polyurethane-polyurea dispersion body with a high solids content.

4. Process according to claim 3, characterized in that the isocyanate index R is controlled to be between 0.91 and 1.0, preferably between 0.93 and 0.98, in particular between 0.94 and 0.96.

5. The method as claimed in claim 4, wherein 10-30 parts of wood pulp is further added and pulverized to 1-4 mm, 500 parts of deionized water is added, 100 parts of polyurethane-polyurea dispersion liquid, 360 parts of deionized water and 10 parts of ethylene glycol are further added, and the mixture is uniformly dispersed with the polyurethane-polyurea dispersion liquid main body at room temperature.

6. The method as claimed in claim 4, wherein a thickener is added, the thickener is sodium polyacrylate or sodium carboxymethyl cellulose, a defoaming agent is added, and the defoaming agent is silicone oil or polyoxypropylene; the addition includes polydimethylsiloxane, polymethylphenylsiloxane wetting agent and leveling agent.

7. Use of the product of the process according to claims 3-6 in self-healing safety tires, characterized in that the finished film-forming substance is applied as a tire burst coating on the tire inner liner.