A flexible one-component reactive cold adhesive and its preparation method and application

Abstract

A flexible single-component reactive cold adhesive, comprising: the cold adhesive is prepared from a polyurethane elastomer polymer (TPU), a tackifying resin and an isocyanate; the isocyanate is a mixture of 2,3'-diphenylmethane diisocyanate and 4,4'-diphenylmethane diisocyanate. The mass ratio of 2,3'-diphenylmethane diisocyanate to 4,4'-diphenylmethane diisocyanate is controlled between 60 and 98:2 and 40. Compared with a single diphenylmethane diisocyanate, the mixture of 2,3'-diphenylmethane diisocyanate and 4,4'-diphenylmethane diisocyanate has better adhesion to silk fabrics or synthetic fibers and metal frames, and has better high temperature resistance and water resistance, and can be quickly cured and dried in a short time, and the strength after curing can meet the needs of daily use.

Description

Technical Field

[0001] The invention relates to a cold pasting adhesive and a preparation method thereof, in particular to a flexible single-component reactive cold pasting adhesive and a preparation method thereof, belonging to the technical field of adhesive preparation. Background Art

[0002] Screen printing is one of the four most common printing methods. During printing, the ink is transferred to the substrate through the mesh of the image part through the extrusion of the scraper, forming the same image as the original. Because the screen printing equipment is simple, easy to operate, simple and low-cost printing and plate making, strong adaptability, and can be printed on curved, spherical and concave and convex substrates, screen printing is recognized by more and more industries and widely used. For example, it is used in circuit boards of household appliances, patterns on textiles, text on panels of refrigerators, televisions, and washing machines, decorations on ceramics, glass, and wall and floor tiles, various commercial advertisements such as electrical appliances, packaging, screen printing of high-end packaging boxes in the packaging and decoration industry, super-large outer packaging and product appearance decoration.

[0003] Screen printing consists of five major elements, namely, screen printing plate, squeegee, ink, printing table and substrate. In the manufacturing process of screen printing plate, the screen made of silk fabric or synthetic fiber fabric needs to be pasted on the screen frame (usually a metal screen frame), which is required to be quickly cured and dried within 30 minutes and pass UV, high temperature and water boiling tests.

[0004] At present, the glues used for bonding wire mesh and metal mesh frame mainly include acrylic acid, chloroprene rubber solvent glue system, 502 system, PE, polyurethane hot melt glue, etc. Among them, chloroprene rubber solvent glue contains harmful volatile substances and has poor stability, acrylic glue has poor high temperature and water resistance, and a short shelf life, while polyurethane hot melt glue consumes a lot of energy in actual use. The two-component PU system glue of foreign brands such as Jingke has a better effect, but due to technical blockades and other reasons, its cost performance is low. It is necessary to develop a glue with the same application performance and better economic benefits. Summary of the invention

[0005] In view of the problems of poor high temperature resistance, harmful volatile substances, poor weather resistance, etc. in the existing adhesives for bonding wire mesh and metal mesh frames, the present invention provides a flexible one-component reactive cold adhesive with good performance, simple preparation and good economic benefits. The present invention adopts a mixture of 2,3'-diphenylmethane diisocyanate and 4,4'-diphenylmethane diisocyanate as a raw material to improve the overall performance of the cold adhesive, and combines TPU and tackifying resin to complement other properties required by the cold adhesive, and ensures the strength after curing.

[0006] According to a first embodiment of the present invention, a flexible one-component reactive cold adhesive is provided.

[0007] A flexible one-component reactive cold adhesive is obtained by mixing and reacting a polyurethane elastomer polymer (TPU), a tackifying resin, an isocyanate and optionally an auxiliary agent in a solvent. The isocyanate is a mixture of 2,3'-diphenylmethane diisocyanate and 4,4'-diphenylmethane diisocyanate.

[0008] Preferably, the mixing mass ratio of 2,3'-diphenylmethane diisocyanate to 4,4'-diphenylmethane diisocyanate in the isocyanate is 60-98:2-40, preferably 70-95:5-30, and more preferably 80-90:10-20.

[0009] Preferably, the components in the cold adhesive are:

[0010] Polyurethane elastomer polymer (TPU) 8 to 20 parts, preferably 9 to 18 parts, more preferably 10 to 15 parts;

[0011] 2 to 20 parts of tackifying resin, preferably 3 to 15 parts, more preferably 4 to 12 parts;

[0012] 2 to 15 parts of isocyanate, preferably 3 to 12 parts, more preferably 4 to 10 parts;

[0013] 0 to 3 parts of auxiliary agent, preferably 0.3 to 2 parts, more preferably 0.5 to 1.5 parts;

[0014] The amount of the solvent is 60 to 95 parts, preferably 70 to 90 parts, and more preferably 75 to 80 parts.

[0015] Preferably, the polyurethane elastomer polymer (TPU) is a fast crystallizing TPU and / or an ultrafast crystallizing TPU composed of alternating rigid blocks containing diisocyanate and flexible segments containing diisocyanate. The rigid blocks containing diisocyanate are obtained by reacting diisocyanate and a chain extender. The flexible segments containing diisocyanate are obtained by reacting diisocyanate and a polyol.

[0016] Preferably, the diisocyanate is diphenylmethane diisocyanate (MDI) and / or toluene diisocyanate (TDI). The chain extender is one or more of glycerol, 1,4-butanediol, 1,6-hexanediol, triethylene glycol, and hexamethylenediamine. The polyol is a polyether polyol with a carbon content of 3 to 15.

[0017] Preferably, the auxiliary agent is one or more of an adhesion promoter, a coupling agent, and a defoaming agent.

[0018] Preferably, the tackifying resin is one or more of C5-C9 petroleum resin and tert-butylphenol-formaldehyde resin.

[0019] Preferably, the solvent is one or more of methyl acetate, ethyl acetate, acetone, and diacetone alcohol.

[0020] Preferably, the accelerator is one or more of triethylenediamine, stannous octoate, and dibutyltin dilaurate. The coupling agent is a silane coupling agent, preferably a KH550 or A-1100 silane coupling agent. The defoamer is an organosilicon defoamer, preferably a BYK141 organosilicon defoamer.

[0021] According to a second embodiment provided by the present invention, a method for preparing a flexible single-component reactive cold adhesive is provided.

[0022] A method for preparing a flexible one-component reactive cold adhesive, the method comprising the following steps:

[0023] 1) uniformly mixing a solvent, a tackifying resin, a polyurethane elastomer polymer (TPU), an isocyanate and optionally an auxiliary agent to obtain a mixture;

[0024] 2) adding isocyanate to the mixture to react, and obtaining a flexible one-component reactive cold adhesive after the reaction is completed.

[0025] Preferably, in step 1), the solvent is one or more of methyl acetate, ethyl acetate, acetone, and diacetone alcohol.

[0026] Preferably, the auxiliary agent is one or more of an adhesion promoter, a coupling agent, and a defoamer. Preferably, the promoter is one or more of triethylenediamine, stannous octoate, and dibutyltin dilaurate. The coupling agent is a silane coupling agent. The defoamer is an organosilicon defoamer.

[0027] Preferably, the tackifying resin is one or more of C5-C9 petroleum resin and tert-butylphenol-formaldehyde resin.

[0028] Preferably, the polyurethane elastomer polymer (TPU) is a fast crystallizing TPU and / or an ultrafast crystallizing TPU composed of alternating rigid blocks containing diisocyanates and flexible segments containing diisocyanates. Among them, the rigid blocks containing diisocyanates are obtained by the reaction of diisocyanates and chain extenders. The flexible segments containing diisocyanates are obtained by the reaction of diisocyanates and polyols. Preferably, the diisocyanates are diphenylmethane diisocyanate (MDI) and / or toluene diisocyanate (TDI). The chain extender is one or more of glycerol, 1,4-butanediol, 1,6-hexanediol, and triethylene glycol. The polyol is a polyether polyol having a carbon content of 3 to 15.

[0029] Preferably, in step 2), the isocyanate is a mixture of 2,3'-diphenylmethane diisocyanate and 4,4'-diphenylmethane diisocyanate. Preferably, the mixing mass ratio of 2,3'-diphenylmethane diisocyanate to 4,4'-diphenylmethane diisocyanate is 60-98:2-40, preferably 70-95:5-30, and more preferably 80-90:10-20.

[0030] Preferably, the added amount of each component is:

[0031] Polyurethane elastomer polymer (TPU) 8 to 20 parts, preferably 9 to 18 parts, more preferably 10 to 15 parts;

[0032] 2 to 20 parts of tackifying resin, preferably 3 to 15 parts, more preferably 4 to 12 parts;

[0033] 2 to 15 parts of isocyanate, preferably 3 to 12 parts, more preferably 4 to 10 parts;

[0034] 0.1 to 3 parts of auxiliary agent, preferably 0.3 to 2 parts, more preferably 0.5 to 1.5 parts;

[0035] The amount of the solvent is 60 to 95 parts, preferably 70 to 90 parts, and more preferably 75 to 80 parts.

[0036] Preferably, the ratio of isocyanate added in step 1) and step 2) is 0.7 to 1.3:1, preferably 0.8 to 1.2:1, and more preferably 0.9 to 1.1:1.

[0037] Preferably, the step 1) is specifically as follows: adding solvent, tackifying resin, polyurethane elastomer polymer (TPU), isocyanate and additives into a planetary kettle in proportion, stirring and reacting at 25-40° C. (preferably 25-30° C.) and vacuum conditions for 1-3 h (preferably 1.5-2 h) to obtain a mixture.

[0038] Preferably, the step 2) is specifically as follows: nitrogen is filled into the planetary reactor to break the vacuum, isocyanate is added in proportion, and after reacting for 1 to 2 hours (preferably 1.3 to 1.8 hours), sampling is performed to detect the content of isocyanate groups, and the reaction is stopped when the mass fraction of the isocyanate group is lower than 1% (preferably lower than 0.5%), thereby obtaining a flexible one-component reactive cold adhesive.

[0039] According to a third embodiment provided by the present invention, an application of a flexible one-component reactive cold adhesive is provided.

[0040] The invention discloses an application of a flexible single-component reactive cold adhesive, wherein the flexible single-component reactive cold adhesive is used for bonding silk fabrics or synthetic fibers to metal frames, preferably for bonding nylon products to aluminum alloy products.

[0041] In the prior art, in the field of screen printing, most of the glues used have performance defects, such as poor high temperature resistance and weather resistance, or contain harmful substances. Faced with complex usage environments, the existing domestic glues are difficult to meet daily usage needs, and the two-component PU system glues of foreign brands such as Jingke have extremely low cost performance. The present invention develops a viscose with excellent application performance and greatly reduced preparation cost and use cost.

[0042] In the present invention, a mixture of 2,3'-diphenylmethane diisocyanate and 4,4'-diphenylmethane diisocyanate is used to prepare a flexible one-component reactive cold adhesive, and the mass ratio of 2,3'-diphenylmethane diisocyanate to 4,4'-diphenylmethane diisocyanate is controlled between 60 and 98:2 and 40. Compared with a single diphenylmethane diisocyanate, the mixture of 2,3'-diphenylmethane diisocyanate and 4,4'-diphenylmethane diisocyanate has better adhesion to silk fabrics or synthetic fibers and metal frames, and has better high temperature resistance and water resistance, and can be quickly cured and dried in a short time. The strength after curing can meet the needs of daily use.

[0043] In the present invention, by adjusting the synthesis route and raw materials of TPU, the high temperature resistance, high humidity resistance and yellowing performance after rapid crystallization are controlled. Based on a large number of experiments, the present invention selects a mixture of ultra-fast crystallization polyether TPU and fast crystallization polyether TPU, so that the prepared flexible single-component reactive cold adhesive can be rapidly crystallized and has excellent weather resistance. Preferably, JM1012, JM2016, JM3011, and JM3015 of Liming Chemical Research Institute are selected as ultra-fast crystallization polyether TPU. JM3030, JT6011, and JT6029 are selected as fast crystallization TPU.

[0044] In the present invention, the volatilization speed of the cold adhesive is adjusted and the curing speed is corrected by changing the ratio of the solvent, and the required properties of the cold adhesive are supplemented by the tackifying resin and the functional additive. Preferably, acetone, ethyl acetate and methyl acetate are selected as the mixed solvent, and the tackifying resin is selected from SL-1410 of Huaqi Chemical, SC-2066 of SI Group, etc.

[0045] Compared with the prior art, the present invention has the following beneficial effects:

[0046] 1. The flexible one-component reactive cold adhesive provided by the present invention is prepared by a mixture of 2,3'-diphenylmethane diisocyanate and 4,4'-diphenylmethane diisocyanate, has good high temperature resistance and moisture resistance, contains no harmful volatile substances, has a fast curing and drying speed, has high strength after curing, and can meet daily use needs.

[0047] 2. The preparation process of the flexible single-component reactive cold adhesive provided by the present invention is simple, the raw materials used are easily available, the cost is low, and it has good economic benefits. DETAILED DESCRIPTION

[0048] The technical solution of the present invention is illustrated below by way of example, and the scope of protection requested by the present invention includes but is not limited to the following embodiments.

[0049] According to a first embodiment of the present invention, a flexible one-component reactive cold adhesive is provided.

[0050] A flexible one-component reactive cold adhesive is obtained by mixing and reacting a polyurethane elastomer polymer (TPU), a tackifying resin, an isocyanate and optionally an auxiliary agent in a solvent. The isocyanate is a mixture of 2,3'-diphenylmethane diisocyanate and 4,4'-diphenylmethane diisocyanate.

[0051] Preferably, the mixing mass ratio of 2,3'-diphenylmethane diisocyanate to 4,4'-diphenylmethane diisocyanate in the isocyanate is 60-98:2-40, preferably 70-95:5-30, and more preferably 80-90:10-20.

[0052] Preferably, the components in the cold adhesive are:

[0053] Polyurethane elastomer polymer (TPU) 8 to 20 parts, preferably 9 to 18 parts, more preferably 10 to 15 parts;

[0054] 2 to 20 parts of tackifying resin, preferably 3 to 15 parts, more preferably 4 to 12 parts;

[0055] 2 to 15 parts of isocyanate, preferably 3 to 12 parts, more preferably 4 to 10 parts;

[0056] 0 to 3 parts of auxiliary agent, preferably 0.3 to 2 parts, more preferably 0.5 to 1.5 parts;

[0057] The amount of the solvent is 60 to 95 parts, preferably 70 to 90 parts, and more preferably 75 to 80 parts.

[0058] Preferably, the polyurethane elastomer polymer (TPU) is a fast crystallizing TPU and / or an ultrafast crystallizing TPU composed of alternating rigid blocks containing diisocyanate and flexible segments containing diisocyanate. The rigid blocks containing diisocyanate are obtained by reacting diisocyanate and a chain extender. The flexible segments containing diisocyanate are obtained by reacting diisocyanate and a polyol.

[0059] Preferably, the diisocyanate is diphenylmethane diisocyanate (MDI) and / or toluene diisocyanate (TDI). The chain extender is one or more of glycerol, 1,4-butanediol, 1,6-hexanediol, and triethylene glycol. The polyol is a polyether polyol having a carbon content of 3 to 15.

[0060] Preferably, the auxiliary agent is one or more of an adhesion promoter, a coupling agent, and a defoaming agent.

[0061] Preferably, the tackifying resin is one or more of C5-C9 petroleum resin and tert-butylphenol-formaldehyde resin.

[0062] Preferably, the solvent is one or more of methyl acetate, ethyl acetate, acetone, and diacetone alcohol.

[0063] Preferably, the accelerator is one or more of triethylenediamine, stannous octoate, and dibutyltin dilaurate. The coupling agent is a silane coupling agent. The defoamer is an organosilicon defoamer.

[0064] According to a second embodiment provided by the present invention, a method for preparing a flexible single-component reactive cold adhesive is provided.

[0065] A method for preparing a flexible one-component reactive cold adhesive, the method comprising the following steps:

[0066] 1) uniformly mixing a solvent, a tackifying resin, a polyurethane elastomer polymer (TPU), an isocyanate and optionally an auxiliary agent to obtain a mixture;

[0067] 2) adding isocyanate to the mixture to react, and obtaining a flexible one-component reactive cold adhesive after the reaction is completed.

[0068] Preferably, in step 1), the solvent is one or more of methyl acetate, ethyl acetate, acetone, and diacetone alcohol.

[0069] Preferably, the auxiliary agent is one or more of an adhesion promoter, a coupling agent, and a defoamer. Preferably, the promoter is one or more of triethylenediamine, stannous octoate, and dibutyltin dilaurate. The coupling agent is a silane coupling agent. The defoamer is an organosilicon defoamer.

[0070] Preferably, the tackifying resin is one or more of C5-C9 petroleum resin and tert-butylphenol-formaldehyde resin.

[0071] Preferably, the polyurethane elastomer polymer (TPU) is a fast crystallizing TPU and / or an ultrafast crystallizing TPU composed of alternating rigid blocks containing diisocyanates and flexible segments containing diisocyanates. Among them, the rigid blocks containing diisocyanates are obtained by the reaction of diisocyanates and chain extenders. The flexible segments containing diisocyanates are obtained by the reaction of diisocyanates and polyols. Preferably, the diisocyanates are diphenylmethane diisocyanate (MDI) and / or toluene diisocyanate (TDI). The chain extender is one or more of glycerol, 1,4-butanediol, 1,6-hexanediol, and triethylene glycol. The polyol is a polyether polyol having a carbon content of 3 to 15.

[0072] Preferably, in step 2), the isocyanate is a mixture of 2,3'-diphenylmethane diisocyanate and 4,4'-diphenylmethane diisocyanate. Preferably, the mixing mass ratio of 2,3'-diphenylmethane diisocyanate to 4,4'-diphenylmethane diisocyanate is 60-98:2-40, preferably 70-95:5-30, and more preferably 80-90:10-20.

[0073] Preferably, the added amount of each component is:

[0074] Polyurethane elastomer polymer (TPU) 8 to 20 parts, preferably 9 to 18 parts, more preferably 10 to 15 parts;

[0075] 2 to 20 parts of tackifying resin, preferably 3 to 15 parts, more preferably 4 to 12 parts;

[0076] 2 to 15 parts of isocyanate, preferably 3 to 12 parts, more preferably 4 to 10 parts;

[0077] 0.1 to 3 parts of auxiliary agent, preferably 0.3 to 2 parts, more preferably 0.5 to 1.5 parts;

[0078] The amount of the solvent is 60 to 95 parts, preferably 70 to 90 parts, and more preferably 75 to 80 parts.

[0079] Preferably, the ratio of isocyanate added in step 1) and step 2) is 0.7 to 1.3:1, preferably 0.8 to 1.2:1, and more preferably 0.9 to 1.1:1.

[0080] Preferably, the step 1) is specifically as follows: adding solvent, tackifying resin, polyurethane elastomer polymer (TPU), isocyanate and additives into a planetary kettle in proportion, stirring and reacting at 25-40° C. (preferably 25-30° C.) and vacuum conditions for 1-3 h (preferably 1.5-2 h) to obtain a mixture.

[0081] Preferably, the step 2) is specifically as follows: nitrogen is filled into the planetary reactor to break the vacuum, isocyanate is added in proportion, and after reacting for 1 to 2 hours (preferably 1.3 to 1.8 hours), sampling is performed to detect the content of isocyanate groups, and the reaction is stopped when the mass fraction of the isocyanate group is lower than 1% (preferably lower than 0.5%), thereby obtaining a flexible one-component reactive cold adhesive.

[0082] According to a third embodiment provided by the present invention, an application of a flexible one-component reactive cold adhesive is provided.

[0083] The invention discloses an application of a flexible single-component reactive cold adhesive, wherein the flexible single-component reactive cold adhesive is used for bonding silk fabrics or synthetic fibers to metal frames, preferably for bonding nylon products to aluminum alloy products.

[0084] Example 1

[0085] 1) Add 20g acetone, 30g ethyl acetate, 30g methyl acetate, 10g C5 petroleum resin, 5g ultrafast crystallization TPU, 5g fast crystallization TPU, 3g isocyanate, 0.3g adhesion promoter, 0.3g coupling agent and 0.4g defoaming agent into a planetary reactor, control the temperature to 30°C, stir under vacuum for 2h, and obtain a mixture after stirring.

[0086] 2) Nitrogen was filled into the planetary reactor to break the vacuum, and 3 g of isocyanate was added. After reacting for 1.5 hours, a sample was taken to detect that the content of isocyanate group was less than 0.5%, and then the reaction was stopped to obtain a flexible single-component reactive cold adhesive.

[0087] Among them, 6g of isocyanate consists of 5.1g of 2,3'-diphenylmethane diisocyanate and 0.9g of 4,4'-diphenylmethane diisocyanate.

[0088] Example 2

[0089] 1) Add 20g acetone, 30g ethyl acetate, 30g methyl acetate, 10g C5 petroleum resin, 5g ultrafast crystallization TPU, 5g fast crystallization TPU, 3g isocyanate, 0.3g adhesion promoter, 0.3g coupling agent and 0.4g defoaming agent into a planetary reactor, control the temperature to 30°C, stir under vacuum for 2h, and obtain a mixture after stirring.

[0090] 2) Nitrogen was filled into the planetary reactor to break the vacuum, and 3 g of isocyanate was added. After reacting for 1.5 hours, a sample was taken to detect that the content of isocyanate group was less than 0.5%, and then the reaction was stopped to obtain a flexible single-component reactive cold adhesive.

[0091] Among them, 6g of isocyanate consists of 5.4g of 2,3'-diphenylmethane diisocyanate and 0.6g of 4,4'-diphenylmethane diisocyanate.

[0092] Example 3

[0093] 1) Add 20g acetone, 30g ethyl acetate, 30g methyl acetate, 10g C5 petroleum resin, 5g ultrafast crystallization TPU, 5g fast crystallization TPU, 3g isocyanate, 0.3g adhesion promoter, 0.3g coupling agent and 0.4g defoaming agent into a planetary reactor, control the temperature to 30°C, stir under vacuum for 2h, and obtain a mixture after stirring.

[0094] 2) Nitrogen was filled into the planetary reactor to break the vacuum, and 3 g of isocyanate was added. After reacting for 1.5 hours, a sample was taken to detect that the content of isocyanate group was less than 0.5%, and then the reaction was stopped to obtain a flexible single-component reactive cold adhesive.

[0095] Among them, 6g of isocyanate consists of 4.8g of 2,3'-diphenylmethane diisocyanate and 1.2g of 4,4'-diphenylmethane diisocyanate.

[0096] Example 4

[0097] 1) Add 20g acetone, 30g ethyl acetate, 30g methyl acetate, 10g C5 petroleum resin, 5g ultrafast crystallization TPU, 5g fast crystallization TPU, 3g isocyanate, 0.3g adhesion promoter, 0.3g coupling agent and 0.4g defoaming agent into a planetary reactor, control the temperature to 30°C, stir under vacuum for 2h, and obtain a mixture after stirring.

[0098] 2) Nitrogen was filled into the planetary reactor to break the vacuum, and 3 g of isocyanate was added. After reacting for 1.5 hours, a sample was taken to detect that the content of isocyanate group was less than 0.5%, and then the reaction was stopped to obtain a flexible single-component reactive cold adhesive.

[0099] Among them, 6g of isocyanate consists of 4.2g of 2,3'-diphenylmethane diisocyanate and 1.8g of 4,4'-diphenylmethane diisocyanate.

[0100] Example 5

[0101] 1) Add 20g acetone, 30g ethyl acetate, 30g methyl acetate, 10g C5 petroleum resin, 5g ultrafast crystallization TPU, 5g fast crystallization TPU, 3g isocyanate, 0.3g adhesion promoter, 0.3g coupling agent and 0.4g defoaming agent into a planetary reactor, control the temperature to 30°C, stir under vacuum for 2h, and obtain a mixture after stirring.

[0102] 2) Nitrogen was filled into the planetary reactor to break the vacuum, and 3 g of isocyanate was added. After reacting for 1.5 hours, a sample was taken to detect that the content of isocyanate group was less than 0.5%, and then the reaction was stopped to obtain a flexible single-component reactive cold adhesive.

[0103] Among them, 6g of isocyanate consists of 5.7g of 2,3'-diphenylmethane diisocyanate and 0.3g of 4,4'-diphenylmethane diisocyanate.

[0104] Example 6

[0105] 1) Add 20g acetone, 30g ethyl acetate, 30g methyl acetate, 10g C5 petroleum resin, 4.8g ultrafast crystallization TPU, 5.2g fast crystallization TPU, 3g isocyanate, 0.3g adhesion promoter, 0.3g coupling agent and 0.4g defoaming agent into a planetary reactor, control the temperature to 30°C, stir under vacuum for 2h, and obtain a mixture after stirring.

[0106] 2) Nitrogen was filled into the planetary reactor to break the vacuum, and 3 g of isocyanate was added. After reacting for 1.5 hours, a sample was taken to detect that the content of isocyanate group was less than 0.5%, and then the reaction was stopped to obtain a flexible single-component reactive cold adhesive.

[0107] Among them, 6g of isocyanate consists of 5.1g of 2,3'-diphenylmethane diisocyanate and 0.9g of 4,4'-diphenylmethane diisocyanate.

[0108] Example 7

[0109] 1) Add 20g acetone, 30g ethyl acetate, 30g methyl acetate, 10g C5 petroleum resin, 4.5g ultrafast crystallization TPU, 5.5g fast crystallization TPU, 3g isocyanate, 0.3g adhesion promoter, 0.3g coupling agent and 0.4g defoaming agent into a planetary reactor, control the temperature to 30°C, stir under vacuum for 2h, and obtain a mixture after stirring.

[0110] 2) Nitrogen was filled into the planetary reactor to break the vacuum, and 3 g of isocyanate was added. After reacting for 1.5 hours, a sample was taken to detect that the content of isocyanate group was less than 0.5%, and then the reaction was stopped to obtain a flexible single-component reactive cold adhesive.

[0111] Among them, 6g of isocyanate consists of 5.1g of 2,3'-diphenylmethane diisocyanate and 0.9g of 4,4'-diphenylmethane diisocyanate.

[0112] Example 8

[0113] 1) Add 20g acetone, 30g ethyl acetate, 30g methyl acetate, 10g C5 petroleum resin, 5g ultrafast crystallization TPU, 5g fast crystallization TPU, 2g isocyanate, 0.3g adhesion promoter, 0.3g coupling agent and 0.4g defoaming agent into a planetary reactor, control the temperature to 30°C, stir under vacuum for 2h, and obtain a mixture after stirring.

[0114] 2) Nitrogen was filled into the planetary reactor to break the vacuum, and 2 g of isocyanate was added. After reacting for 1.5 hours, a sample was taken to detect that the content of isocyanate group was less than 0.5%, and then the reaction was stopped to obtain a flexible single-component reactive cold adhesive.

[0115] Among them, 4g of isocyanate consists of 3.4g of 2,3'-diphenylmethane diisocyanate and 0.6g of 4,4'-diphenylmethane diisocyanate.

[0116] Example 9

[0117] 1) Add 20g acetone, 30g ethyl acetate, 30g methyl acetate, 10g C5 petroleum resin, 5g ultrafast crystallization TPU, 5g fast crystallization TPU, 5g isocyanate, 0.3g adhesion promoter, 0.3g coupling agent and 0.4g defoaming agent into a planetary reactor, control the temperature to 30°C, stir under vacuum for 2h, and obtain a mixture after stirring.

[0118] 2) Nitrogen was filled into the planetary reactor to break the vacuum, and 5 g of isocyanate was added. After reacting for 1.5 hours, a sample was taken to detect that the content of isocyanate group was less than 0.5%, and then the reaction was stopped to obtain a flexible single-component reactive cold adhesive.

[0119] Among them, 10g of isocyanate consists of 8.5g of 2,3'-diphenylmethane diisocyanate and 1.5g of 4,4'-diphenylmethane diisocyanate.

[0120] Example 10

[0121] 1) Add 20g acetone, 30g ethyl acetate, 30g methyl acetate, 10g C5 petroleum resin, 5g ultrafast crystallization TPU, 5g fast crystallization TPU, 1.5g isocyanate, 0.3g adhesion promoter, 0.3g coupling agent and 0.4g defoaming agent into a planetary reactor, control the temperature to 30°C, stir under vacuum for 2h, and obtain a mixture after stirring.

[0122] 2) Nitrogen was filled into the planetary reactor to break the vacuum, and 1.5 g of isocyanate was added. After reacting for 1.5 hours, a sample was taken to detect that the content of isocyanate group was less than 0.5%, and then the reaction was stopped to obtain a flexible single-component reactive cold adhesive.

[0123] Among them, 3g of isocyanate consists of 2.6g of 2,3'-diphenylmethane diisocyanate and 0.4g of 4,4'-diphenylmethane diisocyanate.

[0124] Embodiment 11

[0125] 1) Add 20g acetone, 30g ethyl acetate, 30g methyl acetate, 10g C5 petroleum resin, 5g ultrafast crystallization TPU, 5g fast crystallization TPU, 6g isocyanate, 0.3g adhesion promoter, 0.3g coupling agent and 0.4g defoaming agent into a planetary reactor, control the temperature to 30°C, stir under vacuum for 2h, and obtain a mixture after stirring.

[0126] 2) Nitrogen was filled into the planetary reactor to break the vacuum, and 6 g of isocyanate was added. After reacting for 1.5 hours, a sample was taken to detect that the content of isocyanate group was less than 0.5%, and then the reaction was stopped to obtain a flexible single-component reactive cold adhesive.

[0127] Among them, 12g of isocyanate consists of 10.2g of 2,3'-diphenylmethane diisocyanate and 1.8g of 4,4'-diphenylmethane diisocyanate.

[0128] Example 12

[0129] 1) Add 20g acetone, 30g ethyl acetate, 30g methyl acetate, 10g phenolic resin, 5g ultrafast crystallization TPU, 5g fast crystallization TPU, 3g isocyanate, 0.3g adhesion promoter, 0.3g coupling agent and 0.4g defoaming agent into a planetary reactor, control the temperature to 30°C, stir under vacuum for 2h, and obtain a mixture after stirring.

[0130] 2) Nitrogen was filled into the planetary reactor to break the vacuum, and 3 g of isocyanate was added. After reacting for 1.5 hours, a sample was taken to detect that the content of isocyanate group was less than 0.5%, and then the reaction was stopped to obtain a flexible single-component reactive cold adhesive.

[0131] Among them, 6g of isocyanate consists of 5.1g of 2,3'-diphenylmethane diisocyanate and 0.9g of 4,4'-diphenylmethane diisocyanate.

[0132] Example 13

[0133] 1) Add 20g acetone, 30g ethyl acetate, 30g methyl acetate, 5g C5 petroleum resin, 5g phenolic resin, 5g ultrafast crystallization TPU, 5g fast crystallization TPU, 3g isocyanate, 0.3g adhesion promoter, 0.3g coupling agent and 0.4g defoaming agent into a planetary reactor, control the temperature to 30°C, stir under vacuum for 2h, and obtain a mixture after stirring.

[0134] 2) Nitrogen was filled into the planetary reactor to break the vacuum, and 3 g of isocyanate was added. After reacting for 1.5 hours, a sample was taken to detect that the content of isocyanate group was less than 0.5%, and then the reaction was stopped to obtain a flexible single-component reactive cold adhesive.

[0135] Among them, 6g of isocyanate consists of 5.1g of 2,3'-diphenylmethane diisocyanate and 0.9g of 4,4'-diphenylmethane diisocyanate.

[0136] Embodiment 14

[0137] 1) Add 20g acetone, 40g ethyl acetate, 40g methyl acetate, 10g C5 petroleum resin, 5g ultrafast crystallization TPU, 5g fast crystallization TPU, 0.3g adhesion promoter, 3g isocyanate, 0.3g coupling agent and 0.4g defoaming agent into a planetary reactor, control the temperature to 30°C, stir under vacuum for 2h, and obtain a mixture after stirring.

[0138] 2) Nitrogen was filled into the planetary reactor to break the vacuum, and 3 g of isocyanate was added. After reacting for 1.5 hours, a sample was taken to detect that the content of isocyanate group was less than 0.5%, and then the reaction was stopped to obtain a flexible single-component reactive cold adhesive.

[0139] Among them, 6g of isocyanate consists of 5.1g of 2,3'-diphenylmethane diisocyanate and 0.9g of 4,4'-diphenylmethane diisocyanate.

[0140] Embodiment 15

[0141] 1) Add 35g acetone, 35g methyl acetate, 10g C5 petroleum resin, 5g ultrafast crystallization TPU, 5g fast crystallization TPU, 0.3g adhesion promoter, 3g isocyanate, 0.3g coupling agent and 0.4g defoaming agent into a planetary kettle, control the temperature to 30°C, stir under vacuum for 2h, and obtain a mixture after stirring.

[0142] 2) Nitrogen was filled into the planetary reactor to break the vacuum, and 3 g of isocyanate was added. After reacting for 1.5 hours, a sample was taken to detect that the content of isocyanate group was less than 0.5%, and then the reaction was stopped to obtain a flexible single-component reactive cold adhesive.

[0143] Among them, 6g of isocyanate consists of 5.1g of 2,3'-diphenylmethane diisocyanate and 0.9g of 4,4'-diphenylmethane diisocyanate.

[0144] Example 16

[0145] 1) Add 20g acetone, 30g ethyl acetate, 30g methyl acetate, 10g C5 petroleum resin, 7.5g ultrafast crystallization TPU, 7.5g fast crystallization TPU, 0.3g adhesion promoter, 3g isocyanate, 0.3g coupling agent and 0.4g defoaming agent into a planetary reactor, control the temperature to 30°C, stir under vacuum for 2h, and obtain a mixture after stirring.

[0146] 2) Nitrogen was filled into the planetary reactor to break the vacuum, and 3 g of isocyanate was added. After reacting for 1.5 hours, a sample was taken to detect that the content of isocyanate group was less than 0.5%, and then the reaction was stopped to obtain a flexible single-component reactive cold adhesive.

[0147] Among them, 6g of isocyanate consists of 5.1g of 2,3'-diphenylmethane diisocyanate and 0.9g of 4,4'-diphenylmethane diisocyanate.

[0148] Comparative Example 1

[0149] 1) Add 20g acetone, 30g ethyl acetate, 30g methyl acetate, 10g C5 petroleum resin, 5g ultrafast crystallization TPU, 5g fast crystallization TPU, 0.3g adhesion promoter, 3g isocyanate, 0.3g coupling agent and 0.4g defoaming agent into a planetary reactor, control the temperature to 30°C, stir under vacuum for 2h, and obtain a mixture after stirring.

[0150] 2) Nitrogen was filled into the planetary reactor to break the vacuum, and 3 g of isocyanate was added. After reacting for 1.5 hours, a sample was taken to detect that the content of isocyanate group was less than 0.5%, and then the reaction was stopped to obtain a flexible single-component reactive cold adhesive.

[0151] Among them, 6 g of isocyanate were all 2,3'-diphenylmethane diisocyanate.

[0152] Comparative Example 2

[0153] 1) Add 20g acetone, 30g ethyl acetate, 30g methyl acetate, 10g C5 petroleum resin, 5g ultrafast crystallization TPU, 5g fast crystallization TPU, 0.3g adhesion promoter, 3g isocyanate, 0.3g coupling agent and 0.4g defoaming agent into a planetary reactor, control the temperature to 30°C, stir under vacuum for 2h, and obtain a mixture after stirring.

[0154] 2) Nitrogen was filled into the planetary reactor to break the vacuum, and 3 g of isocyanate was added. After reacting for 1.5 hours, a sample was taken to detect that the content of isocyanate group was less than 0.5%, and then the reaction was stopped to obtain a flexible single-component reactive cold adhesive.

[0155] Among them, 6 g of isocyanate were all 4,4'-diphenylmethane diisocyanate.

[0156] Comparative Example 3

[0157] 1) Add 20g acetone, 30g ethyl acetate, 30g methyl acetate, 10g C5 petroleum resin, 5g ultrafast crystallization TPU, 5g fast crystallization TPU, 0.3g adhesion promoter, 3g isocyanate, 0.3g coupling agent and 0.4g defoaming agent into a planetary reactor, control the temperature to 30°C, stir under vacuum for 2h, and obtain a mixture after stirring.

[0158] 2) Nitrogen was filled into the planetary reactor to break the vacuum, and 3 g of isocyanate was added. After reacting for 1.5 hours, a sample was taken to detect that the content of isocyanate group was less than 0.5%, and then the reaction was stopped to obtain a flexible single-component reactive cold adhesive.

[0159] Among them, 6g of isocyanate consists of 3g of 2,3'-diphenylmethane diisocyanate and 3g of 4,4'-diphenylmethane diisocyanate.

[0160] Comparative Example 4

[0161] 1) Add 20g acetone, 30g ethyl acetate, 30g methyl acetate, 10g C5 petroleum resin, 5g ultrafast crystallization TPU, 5g fast crystallization TPU, 0.3g adhesion promoter, 3g isocyanate, 0.3g coupling agent and 0.4g defoaming agent into a planetary reactor, control the temperature to 30°C, stir under vacuum for 2h, and obtain a mixture after stirring.

[0162] 2) Nitrogen was filled into the planetary reactor to break the vacuum, and 3 g of isocyanate was added. After reacting for 1.5 hours, a sample was taken to detect that the content of isocyanate group was less than 0.5%, and then the reaction was stopped to obtain a flexible single-component reactive cold adhesive.

[0163] Among them, 6g of isocyanate consists of 2g of 2,3'-diphenylmethane diisocyanate and 4g of 4,4'-diphenylmethane diisocyanate.

[0164] Comparative Example 5

[0165] 1) Add 20g acetone, 30g ethyl acetate, 30g methyl acetate, 10g C5 petroleum resin, 5g ultrafast crystallization TPU, 5g fast crystallization TPU, 0.3g adhesion promoter, 0.5g isocyanate, 0.3g coupling agent and 0.4g defoaming agent into a planetary reactor, control the temperature to 30°C, stir under vacuum for 2h, and obtain a mixture after stirring.

[0166] 2) Nitrogen was filled into the planetary reactor to break the vacuum, and 0.5 g of isocyanate was added. After reacting for 1.5 hours, a sample was taken to detect that the content of isocyanate group was less than 0.5%, and then the reaction was stopped to obtain a flexible single-component reactive cold adhesive.

[0167] Among them, 1g of isocyanate is composed of 0.8g of 2,3'-diphenylmethane diisocyanate and 0.2g of 4,4'-diphenylmethane diisocyanate.

[0168] Comparative Example 6

[0169] 1) Add 20 g acetone, 30 g ethyl acetate, 30 g methyl acetate, 10 g C5 petroleum resin, 0.3 g adhesion promoter, 3 g isocyanate, 0.3 g coupling agent and 0.4 g defoaming agent into a planetary reactor, control the temperature to 30°C, stir under vacuum for 2 h, and obtain a mixture after stirring.

[0170] 2) Nitrogen was filled into the planetary reactor to break the vacuum, and 3 g of isocyanate was added. After reacting for 1.5 hours, a sample was taken to detect that the content of isocyanate group was less than 0.5%, and then the reaction was stopped to obtain a flexible single-component reactive cold adhesive.

[0171] Among them, 6g of isocyanate consists of 5.1g of 2,3'-diphenylmethane diisocyanate and 0.9g of 4,4'-diphenylmethane diisocyanate.

[0172] Comparative Example 7

[0173] 1) Add 20g acetone, 30g ethyl acetate, 30g methyl acetate, 5g ultrafast crystallization TPU, 5g fast crystallization TPU, 0.3g adhesion promoter, 3g isocyanate, 0.3g coupling agent and 0.4g defoaming agent into a planetary reactor, control the temperature to 30°C, stir under vacuum for 2h, and obtain a mixture after stirring.

[0174] 2) Nitrogen was filled into the planetary reactor to break the vacuum, and 3 g of isocyanate was added. After reacting for 1.5 hours, a sample was taken to detect that the content of isocyanate group was less than 0.5%, and then the reaction was stopped to obtain a flexible single-component reactive cold adhesive.

[0175] Among them, 6g of isocyanate consists of 5.1g of 2,3'-diphenylmethane diisocyanate and 0.9g of 4,4'-diphenylmethane diisocyanate.

[0176] Comparative Example 8

[0177] Acrylic adhesive available.

[0178] Comparative Example 9

[0179] Currently we have Jingke two-component PU system adhesive.

[0180] The cold-stick adhesives prepared in Examples 1 to 16 and Comparative Examples 1 to 7 and the existing adhesives in Comparative Examples 8 and 9 were used to bond nylon mesh cloth to an aluminum alloy frame. The curing speed and bonding strength after curing were tested. The high temperature resistance was also tested. The test results are shown in the following table.

[0181]

[0182]

[0183] The flexible one-component reactive cold-adhesive provided by the present invention has good high temperature resistance and water resistance, fast curing speed, high strength after curing, and can meet the needs of daily use. The optimal ratio range of raw materials is obtained based on a large number of experiments. Compared with comparative examples 1 to 7, the present invention uses a mixture of 2,3'-diphenylmethane diisocyanate and 4,4'-diphenylmethane diisocyanate, which greatly improves the comprehensive performance of the cold-adhesive. Compared with the existing viscose in comparative examples 8 and 9, the flexible one-component reactive cold-adhesive provided by the present invention shortens the curing time and solves the debonding problem.

Claims

1. A flexible one-component reactive cold adhesive, characterized in that: The cold adhesive is obtained by mixing and reacting a polyurethane elastomer polymer TPU, a tackifying resin, an isocyanate and an optional auxiliary agent in a solvent; the isocyanate is a mixture of 2,3'-diphenylmethane diisocyanate and 4,4'-diphenylmethane diisocyanate in a mass ratio of 60-98:2-40; The components of the cold adhesive are: 9-18 parts of polyurethane elastomer polymer TPU; 3-15 parts of tackifying resin; 3-12 parts of isocyanate; 0.3-2 parts of auxiliary agent; 70-90 parts of solvent; The polyurethane elastomer polymer TPU is a fast crystallization type TPU and an ultra-fast crystallization type TPU which are alternately composed of rigid blocks containing diisocyanate and flexible segments containing diisocyanate; wherein the fast crystallization type TPU is JT6029 and the ultra-fast crystallization type TPU is JM1012.

2. The cold adhesive according to claim 1, characterized in that: The mixing mass ratio of 2,3'-diphenylmethane diisocyanate to 4,4'-diphenylmethane diisocyanate in the isocyanate is 70-95:5-30.

3. The cold adhesive according to claim 2, characterized in that: The mixing mass ratio of 2,3'-diphenylmethane diisocyanate to 4,4'-diphenylmethane diisocyanate in the isocyanate is 80-90:10-20.

4. The cold adhesive according to any one of claims 1 to 3, characterized in that: The components of the cold adhesive are: 10-15 parts of polyurethane elastomer polymer TPU; 4-12 parts of tackifying resin; 4-10 parts of isocyanate; 0.5-1.5 parts of auxiliary agent; and 75-80 parts of solvent.

5. The cold adhesive according to any one of claims 1 to 3, characterized in that: The auxiliary agent is one or more of an adhesion promoter, a coupling agent, and a defoaming agent; the tackifying resin is one or more of C5-C9 petroleum resin and tert-butyl phenolic resin; the solvent is one or more of methyl acetate, ethyl acetate, acetone, and diacetone alcohol; the promoter is one or more of triethylenediamine, stannous octoate, and dibutyltin dilaurate; the coupling agent is a silane coupling agent; and the defoaming agent is a silicone defoaming agent.

6. A method for preparing the flexible one-component reactive cold adhesive as claimed in any one of claims 1 to 5, characterized in that: The method comprises the following steps: 1) uniformly mixing a solvent, a tackifying resin, a polyurethane elastomer polymer TPU, an isocyanate and optionally an auxiliary agent to obtain a mixture; 2) adding isocyanate to the mixture to react, and obtaining a flexible one-component reactive cold adhesive after the reaction is completed; The ratio of isocyanate added in step 1) and step 2) is 0.7-1.3:

1.

7. The preparation method according to claim 6, characterized in that: The ratio of isocyanate added in step 1) and step 2) is 0.8-1.2:

1.

8. The preparation method according to claim 7, characterized in that: The ratio of isocyanate added in step 1) and step 2) is 0.9-1.1:

1.

9. The preparation method according to claim 6, characterized in that: The step 1) specifically comprises: adding a solvent, a tackifying resin, a polyurethane elastomer polymer TPU, an isocyanate and an auxiliary agent into a planetary kettle in proportion, stirring and reacting at 25-40° C. and vacuum conditions for 1-3 hours to obtain a mixture; and / or The step 2) is specifically as follows: nitrogen is filled into the planetary reactor to break the vacuum, isocyanate is added in proportion, and after reacting for 1 to 2 hours, samples are taken to detect the content of isocyanate groups. When the mass fraction of isocyanate groups is less than 1%, the reaction is stopped to obtain a flexible one-component reactive cold adhesive.

10. The preparation method according to claim 9, characterized in that: The step 1) specifically comprises: adding a solvent, a tackifying resin, a polyurethane elastomer polymer TPU, an isocyanate and an auxiliary agent into a planetary kettle in proportion, stirring and reacting at 25-30° C. and vacuum conditions for 1.5-2 hours to obtain a mixture; and / or The step 2) is specifically as follows: nitrogen is filled into the planetary reactor to break the vacuum, isocyanate is added in proportion, and after reacting for 1.3 to 1.8 hours, samples are taken to detect the content of isocyanate groups. When the mass fraction of isocyanate groups is lower than 0.5%, the reaction is stopped to obtain a flexible one-component reactive cold adhesive.

11. An application of the flexible one-component reactive cold adhesive as claimed in any one of claims 1 to 5 or an application of the flexible one-component reactive cold adhesive prepared by the method as claimed in any one of claims 7 to 10, characterized in that: The flexible single-component reactive cold adhesive is used for bonding silk fabrics or synthetic fibers to a metal frame.

12. The use according to claim 11, characterized in that: The flexible single-component reactive cold adhesive is used for bonding nylon products and aluminum alloy products.

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