阅读说明：本技术 汽车顶棚用单组份无溶剂热熔胶及其制备方法、使用方法 (Single-component solvent-free hot melt adhesive for automobile roof, and preparation method and use method thereof ) 是由 张来 于 2021-01-28 设计创作，主要内容包括：本发明公开了一种汽车顶棚用单组份无溶剂热熔胶及其制备方法、使用方法,所述热熔胶由以下重量份数的原料组成：45～55份的二环己基甲烷二异氰酸酯、70～80份的聚己内酯多元醇、5～15份的聚氧化丙烯二醇、1～3份的三羟甲基丙烷三丙烯酸酯、0.1～5份的扩链剂、0.1～2份的固化剂、0.1～3的聚碳化二亚胺、0.1～2份的附着力促进剂、0.1～0.5份的催化剂和0.1～0.3份的抗氧剂。本发明无需添加有机溶剂和双份A类物质,能够极大地减少VOC排放量,有效改善热熔胶对环境的污染,其80℃的粘度为5600mpa.s,按重量比测得NOC％为7.8％,且拉伸强度为161Mpa,断裂伸长率为170％,初始层剥间剥离强度为8N/mm。(The invention discloses a single-component solvent-free hot melt adhesive for an automobile roof, a preparation method and a use method thereof, wherein the hot melt adhesive is prepared from the following raw materials in parts by weight: 45-55 parts of dicyclohexylmethane diisocyanate, 70-80 parts of polycaprolactone polyol, 5-15 parts of polyoxypropylene glycol, 1-3 parts of trimethylolpropane triacrylate, 0.1-5 parts of chain extender, 0.1-2 parts of curing agent, 0.1-3 parts of polycarbodiimide, 0.1-2 parts of adhesion promoter, 0.1-0.5 part of catalyst and 0.1-0.3 part of antioxidant. According to the invention, an organic solvent and a double part of A-type substance are not required to be added, the discharge amount of VOC can be greatly reduced, the pollution of the hot melt adhesive to the environment is effectively improved, the viscosity of the hot melt adhesive at 80 ℃ is 5600mpa.s, the NOC% is 7.8% measured according to the weight ratio, the tensile strength is 161Mpa, the elongation at break is 170%, and the initial interlaminar peeling strength is 8N/mm.)

1. The single-component solvent-free hot melt adhesive for the automobile roof is characterized by comprising the following raw materials in parts by weight: 45-55 parts of dicyclohexylmethane diisocyanate, 70-80 parts of polycaprolactone polyol, 5-15 parts of polyoxypropylene glycol, 1-3 parts of trimethylolpropane triacrylate, 0.1-5 parts of chain extender, 0.1-2 parts of curing agent, 0.1-3 parts of polycarbodiimide, 0.1-2 parts of adhesion promoter, 0.1-0.5 part of catalyst and 0.1-0.3 part of antioxidant.

2. The one-component, solvent-free hot melt adhesive for automobile roofs of claim 1, wherein the average molecular weight of said polycaprolactone polyol is 2000-4000.

3. The one-component, solvent-free hot melt adhesive for automobile roofs of claim 1, wherein the average molecular weight of said polyoxypropylene diol is 3000-4000.

4. The one-component, solvent-free hot melt adhesive for automotive roofs of claim 1, wherein said chain extender is one or more of 1, 4-butanediol, 1, 6-hexanediol, glycerol, trimethylolpropane, diethylene glycol, triethylene glycol, neopentyl glycol, sorbitol, diethylaminoethanol, 3 '-dichloro-4, 4' -diaminodiphenylmethane, ethylenediamine, N-dihydroxy (diisopropyl) aniline, hydroquinone-bis (β -hydroxyethyl) ether.

5. The single-component solvent-free hot melt adhesive for the automobile roof as claimed in claim 1, wherein the curing agent comprises one or two of an aliphatic amine curing agent and an imidazole curing agent;

the aliphatic amine curing agent is one or a mixture of more of ethylenediamine, hexamethylenediamine, diethylenetriamine and triethylene tetramine;

the imidazole curing agent is a closed product prepared by reacting various imidazoles with Toluene Diisocyanate (TDI), isophorone diisocyanate (IPDI), Hexamethylene Diisocyanate (HDI) and diphenylmethane diisocyanate (MDI).

6. The preparation method of the single-component solvent-free hot melt adhesive for the automobile roof, which is characterized by comprising the following steps of:

s1: taking 70-80 parts of polycaprolactone polyol and 5-15 parts of polyoxypropylene glycol, fully mixing uniformly, and dehydrating for 2-4 hours in a vacuum environment at the dehydration temperature of 100-160 ℃;

s2: cooling the mixture obtained by dehydration in the step S1 to 50-90 ℃, adding 0.1-3 parts of polycarbodiimide, 0.1-2 parts of curing agent and 0.1-2 parts of adhesion promoter, and stirring for 5-10 minutes;

s3: adding 45-55 parts of dicyclohexylmethane diisocyanate, 1-3 parts of trimethylolpropane triacrylate, 0.1-0.5 part of catalyst and 0.1-0.3 part of antioxidant into the stirring container in the step S2, preserving heat at 50-90 ℃, and reacting for 20-60 minutes;

s4: and adding 0.1-5 parts of chain extender, and continuously stirring for 10-40 minutes to obtain a hot melt adhesive finished product.

7. The use method of the single-component solvent-free hot melt adhesive for the automobile roof is characterized in that the hot melt adhesive is applied between a base layer and a bonding material to form an intermediate layer; wherein the environmental temperature is 20-30 ℃, the humidity is 40-80%, and the surface temperature of the composite material is 20-30 ℃.

Technical Field

The invention relates to a single-component solvent-free hot melt adhesive for an automobile roof, a preparation method and a use method thereof, and belongs to the technical field of hot melt adhesives.

Background

In industrial production, materials and compounding are often realized by means of adhesives, common compound adhesives are divided into solvent adhesives and solvent-free adhesives, the solvent adhesives and the solvent-free adhesives can be realized in a single-component or double-component mode, and the solvent adhesives and the solvent-free adhesives are used in a heating mode or a non-heating mode according to formula components.

In typical coating fields, for example, metal coating, and metal plate coating, which are processing techniques for bonding a plastic film to a metal plate by hot pressing the plastic film and the metal plate at a high temperature, have been produced in japan in 1977, and are first used for can making, instead of internal coating and external coating, and have been developed into various fields such as building material interiors, home appliance housings, and ship interiors.

At present, the processing of metal plate coating is mainly to coat a bi-component solvent adhesive on the surface of a metal plate, to bake the metal plate at a high temperature through a long-distance drying tunnel, to volatilize the solvent, to adhere a film on the surface of the metal plate at a high temperature by means of the adhesive in a molten state, and to form firm bonding after cooling. When the Laminated sheet is applied to a Laminated sheet in the can manufacturing industry, the Laminated sheet is commonly called Laminated Steel (Laminated Steel), and the Laminated sheet is formed by laminating a PET, PC, PE or PP film and a metal sheet (a galvanized sheet, a cold-rolled sheet, an aluminum sheet, a stainless Steel sheet, an alloy sheet and the like) by adopting the process. In the process, a large amount of organic solvent is volatilized to influence the environment, and the solvent used in the process can leave harmful substances in the final product. These harmful substances have a harmful effect on the human body when they permeate into foods, cosmetics, and the like. Therefore, the inner wall of a metal packaging can, particularly a food can and a cosmetic can, is not coated by adopting the process at present, and the outer wall of the can body is only coated by adopting the process.

However, the inner wall of the metal packaging can must be coated to meet the relevant industrial standards, and for this requirement, the existing treatment method is to coat the inner wall of the can with resin. However, since the paint used in this coating process contains a bisphenol a (Bis-phenol a) substance, which is an internationally recognized environmental hormone, as a harmful substance of the environmental hormone, elution occurs. Once bisphenol A is dissolved out excessively and enters the packaged object, the adverse effect on the human body can be generated.

In the prior art, a solvent is used as a carrier in a two-component solvent-based adhesive, and common solvents comprise ethyl acetate, butanone, acetone, xylene, toluene, dichloromethane and the like. The molecular weight of the adhesive can be reacted to be large enough in the synthesis process, and the viscosity is kept at a proper level under the regulation of the solvent; in addition, the solubility of the solvent is utilized to more conveniently and easily add effective hydrolysis resistance agent and other functional materials, and the performance requirements such as boiling resistance, high-temperature boiling resistance, double-eight-five experiment resistance, salt mist resistance, hydrochloric acid resistance, electrolyte resistance, deep drawing resistance and the like can be more easily met. Therefore, the traditional bi-component solvent adhesive becomes a representative of thin material composite high-performance adhesive, and is suitable for a plurality of film material composite processing occasions with higher requirements on the performance.

However, two-part solvent-based adhesives also suffer from a number of drawbacks. In the process of producing the bi-component solvent-based adhesive, because a large amount of organic solvent is used, the VOC emission is large, and a large amount of environmental protection facilities and environmental protection disposal cost are required to be invested for preventing environmental pollution. In addition, when the bi-component solvent-based adhesive is subjected to composite production, the organic solvent is dried by means of high-temperature baking in a long-distance baking channel, and the general defects of complex process, high energy consumption, large equipment occupation area, high comprehensive cost and the like exist. In addition, in the use process of a composite structure product formed by bonding the two-component solvent-based adhesive, because a large amount of solvent is used, the potential safety hazard of enterprises is high, the solvent remained in the colloid is slowly precipitated, and certain potential safety hazard exists on human bodies and the environment, so that the solvent-based adhesive also has a plurality of use limitations.

However, the existing single-component solvent-free hot melt adhesive or two-component solvent-free adhesive is synthesized by using conventional polyester polyether, the production process is environment-friendly and has little pollution, and solvent toxicity residue is avoided, but when the molecular weight is synthesized to be large enough, the viscosity is overlarge, the leveling, the spreading and the coating performances are poor, and the single-component solvent-free hot melt adhesive or the two-component solvent-free adhesive cannot be suitable for plastic-aluminum and other composite processes; the molecular weight synthesis is small, and the performances of boiling resistance, high-temperature boiling resistance, double-eighty-five experiment resistance, salt mist resistance, hydrochloric acid resistance, electrolyte resistance, deep drawing resistance and the like can not meet the requirements.

Particularly, when the adhesive is used for adhering a composite film of a stainless steel frame of an automobile roof, the hot melt adhesive is required to have higher tensile strength and peel strength due to the complex frame shape and large later-stage stress strength; therefore, how to overcome the defects of synthesis and performance of the solvent-free hot flux, and satisfy the tensile strength and the peel strength after film pasting while eliminating the influence of the solvent in the solvent-based adhesive on the environment and the human body becomes a difficult problem for technicians in the field to overcome.

Disclosure of Invention

The invention aims to provide a single-component solvent-free hot melt adhesive for an automobile ceiling, and a preparation method and a use method thereof.

In order to achieve the purpose, the invention adopts the technical scheme that: the single-component solvent-free hot melt adhesive for the automobile roof comprises the following raw materials in parts by weight: the hot melt adhesive is prepared from the following raw materials in parts by weight: 45-55 parts of dicyclohexylmethane diisocyanate, 70-80 parts of polycaprolactone polyol, 5-15 parts of polyoxypropylene glycol, 1-3 parts of trimethylolpropane triacrylate, 0.1-5 parts of chain extender, 0.1-2 parts of curing agent, 0.1-3 parts of polycarbodiimide, 0.1-2 parts of adhesion promoter, 0.1-0.5 part of catalyst and 0.1-0.3 part of antioxidant.

The further improved scheme in the technical scheme is as follows:

1. in the scheme, the average molecular weight of the polycaprolactone polyol is 2000-4000.

2. In the above scheme, the average molecular weight of the polyoxypropylene diol is 3000-4000.

3. In the above scheme, the chain extender is one or a mixture of more of 1, 4-butanediol, 1, 6-hexanediol, glycerol, trimethylolpropane, diethylene glycol, triethylene glycol, neopentyl glycol, sorbitol, diethylaminoethanol, 3 '-dichloro-4, 4' -diaminodiphenylmethane, ethylenediamine, N-dihydroxy (diisopropyl) aniline, and hydroquinone-bis (β -hydroxyethyl) ether.

4. In the above scheme, the curing agent comprises one or two of aliphatic amine curing agent and imidazole curing agent;

the aliphatic amine curing agent is one or a mixture of more of ethylenediamine, hexamethylenediamine, diethylenetriamine and triethylene tetramine;

the imidazole curing agent is a closed product prepared by reacting various imidazoles with Toluene Diisocyanate (TDI), isophorone diisocyanate (IPDI), Hexamethylene Diisocyanate (HDI) and diphenylmethane diisocyanate (MDI).

In order to achieve the above purpose, the invention also provides a technical scheme that: a preparation method of a single-component solvent-free hot melt adhesive for an automobile roof comprises the following steps:

s1: taking 70-80 parts of polycaprolactone polyol and 5-15 parts of polyoxypropylene glycol, fully mixing uniformly, and dehydrating for 2-4 hours in a vacuum environment at the dehydration temperature of 100-160 ℃;

s2: cooling the mixture obtained by dehydration in the step S1 to 50-90 ℃, adding 0.1-3 parts of polycarbodiimide, 0.1-2 parts of curing agent and 0.1-2 parts of adhesion promoter, and stirring for 5-10 minutes;

s3: adding 45-55 parts of dicyclohexylmethane diisocyanate, 1-3 parts of trimethylolpropane triacrylate, 0.1-0.5 part of catalyst and 0.1-0.3 part of antioxidant into the stirring container in the step S2, preserving heat at 50-90 ℃, and reacting for 20-60 minutes;

s4: and adding 0.1-5 parts of chain extender, and continuously stirring for 10-40 minutes to obtain a hot melt adhesive finished product.

In order to achieve the purpose, the invention also provides another technical scheme that: a use method of a single-component solvent-free hot melt adhesive for an automobile roof is characterized in that the hot melt adhesive is applied between a base layer and a bonding material to form an intermediate layer; wherein the environmental temperature is 20-30 ℃, the humidity is 40-80%, and the surface temperature of the composite material is 20-30 ℃.

Due to the application of the technical scheme, compared with the prior art, the invention has the following advantages:

1. according to the single-component solvent-free hot melt adhesive, the preparation method and the use method thereof, organic solvent and double A-component substances are not required to be added, VOC (volatile organic compound) emission can be greatly reduced, the pollution of the hot melt adhesive to the environment is effectively improved, and the solvent is not required to be stored, used and discharged, so that the investment of environmental protection facilities of enterprises is reduced, the cost of environmental protection disposal is reduced, and the potential safety hazard brought to the enterprises by solvent storage is avoided.

2. The invention relates to a single-component solvent-free hot melt adhesive and a preparation method and a using method thereof, wherein the viscosity of a hot melt adhesive prepared from 45-55 parts of dicyclohexylmethane diisocyanate, 70-80 parts of polycaprolactone polyol, 5-15 parts of polyoxypropylene glycol, 1-3 parts of trimethylolpropane triacrylate, 0.1-5 parts of a chain extender, 0.1-2 parts of a curing agent, 0.1-3 parts of polycarbodiimide, 0.1-2 parts of an adhesion promoter, 0.1-0.5 part of a catalyst and 0.1-0.3 part of an antioxidant at 80 ℃ is 5600mpa.s, the NOC% is 7.8% measured according to the weight ratio, the tensile strength is 161MPa, the elongation at break is 170%, and the initial interlayer peeling strength is 8N/mm.

Detailed Description

Example 1: the single-component solvent-free hot melt adhesive for the automobile roof comprises the following raw materials in parts by weight: 45 parts of dicyclohexylmethane diisocyanate, 70 parts of polycaprolactone polyol, 5 parts of polyoxypropylene glycol, 1 part of trimethylolpropane triacrylate, 1 part of a chain extender, 1 part of a curing agent, 1 part of polycarbodiimide, 1 part of an adhesion promoter, 0.1 part of a catalyst and 0.1 part of an antioxidant.

The average molecular weight of the polycaprolactone polyol is 2000; the average molecular weight of the polyoxypropylene diol is 3000.

The chain extender is one or a mixture of more of 1, 4-butanediol, 1, 6-hexanediol, glycerol, trimethylolpropane, diethylene glycol, triethylene glycol, neopentyl glycol, sorbitol, diethylaminoethanol, 3 '-dichloro-4, 4' -diaminodiphenylmethane, ethylenediamine, N-dihydroxy (diisopropyl) aniline and hydroquinone-di (beta-hydroxyethyl) ether.

The curing agent comprises one or two of aliphatic amine curing agent and imidazole curing agent;

the aliphatic amine curing agent is one or a mixture of more of ethylenediamine, hexamethylenediamine, diethylenetriamine and triethylene tetramine;

the imidazole curing agent is a closed product prepared by reacting various imidazoles with Toluene Diisocyanate (TDI), isophorone diisocyanate (IPDI), Hexamethylene Diisocyanate (HDI) and diphenylmethane diisocyanate (MDI).

A preparation method of a single-component solvent-free hot melt adhesive for an automobile roof comprises the following steps:

s1: taking 70 parts of polycaprolactone polyol and 5 parts of polyoxypropylene glycol, fully and uniformly mixing, and dehydrating for 2 hours in a vacuum environment at the dehydration temperature of 100-DEG C;

s2: cooling the mixture obtained by dehydration in the step S1 to 50 ℃, adding 1 part of polycarbodiimide, 1 part of curing agent and 1 part of adhesion promoter, and stirring for 5 minutes;

s3: adding 45 parts of dicyclohexylmethane diisocyanate, 1 part of trimethylolpropane triacrylate, 0.1 part of catalyst and 0.1 part of antioxidant into the stirring container in the step S2, preserving the temperature at 50 ℃, and reacting for 20 minutes;

s4: adding 01 parts of chain extender, and continuously stirring for 10 minutes to obtain a hot melt adhesive finished product.

Wherein the antioxidant is irganox 1010.

Wherein the catalyst is organic bismuth.

Wherein the hydrolysis resistant agent refers to polycarbodiimide Stabaxol P200.

Wherein the latent curing agent refers to ketoxime blocked isocyanate curing agent.

Wherein the chain extender is a dimethylolbutyric acid modifier.

Wherein the adhesion promoter is Degussa LTW (an ester compound).

A method for using a single-component solvent-free hot melt adhesive for an automobile roof comprises the steps of applying a hot melt adhesive between a base layer and a bonding material to form a middle layer; wherein the environmental temperature is 20 ℃, the humidity is 40%, and the surface temperature of the composite material is 20 ℃.

Performance evaluation:

the viscosity of the one-component solvent-free hot-melt adhesive of this example was measured using an SNB-AI viscometer, spindle # 27. The single-component solvent-free hot melt adhesive of the embodiment is heated and stirred in an SNB-AI viscometer for 30 minutes, the displayed value is read, and the displayed value of the viscosity is kept unchanged for 20 minutes, namely the measured viscosity of the hot melt adhesive is obtained. The one-component, solvent-free hot melt adhesive of this example had a viscosity of 5000mpa.s at 80 ℃.

Determination of the isocyanate group content (NCO%): the single-component solvent-free hot-melt adhesive of this example was reacted for 20 minutes with an excess of di-N-butylamine in N-methylpyrrolidone, and then the NCO% was determined by titration with hydrochloric acid, and the NCO% by weight was determined to be 7.6%.

The maximum load when the backboard sample breaks has different tensile strengths for the backboards with different thicknesses and different materials, and the tensile strength of the general KPK/KPE backboard is not less than 120Mpa longitudinally and not less than 120Mpa transversely. According to the regulation of GB/T13542.2-2009, chapter 11. The test piece is 200mm long and (15 +/-1) mm wide, and five test pieces are taken in the transverse direction and the longitudinal direction respectively. The measurement accuracy of the width of the sample is not less than 0.1 mm. Two marker lines spaced at least 50mm apart are marked in the middle of the specimen and the load is applied at a tensile rate of 100mm/min until the specimen single component fails as an end point. The results were obtained as the median of five test values in the transverse and longitudinal directions, respectively.

This example is 150MPa

The maximum load when the backboard sample breaks has different tensile strengths for the backboards with different thicknesses and different materials, and the breaking elongation of the general KPK/KPE backboard is more than or equal to 100 percent in the longitudinal direction and more than or equal to 100 percent in the transverse direction. According to the regulation of GB/T13542.2-2009, chapter 11. The test piece is 200mm long and (15 +/-1) mm wide, and five test pieces are taken in the transverse direction and the longitudinal direction respectively. The measurement accuracy of the width of the sample is not less than 0.1 mm. Two marker lines spaced at least 50mm apart are marked in the middle of the specimen and the load is applied at a tensile rate of 100mm/min until the specimen single component fails as an end point. The results were obtained as the median of five test values in the transverse and longitudinal directions, respectively. This embodiment is 160%.

The adhesive strength between the layers of the back plate is tested, and the most common standard is more than or equal to 4N/10 mm. According to the provisions of GB/T2790-1995. The test piece is 200mm long and (15 +/-1) mm wide, and five test pieces are taken in the transverse direction and the longitudinal direction respectively. The width of the test specimen is not less than 0.1mm, and the test specimen tears apart a layer of the composite material (fluorine/PET) along the length direction. The 180 DEG peeling test was carried out at a peeling speed of 100mm/min, and the median of five test values in the transverse direction and the longitudinal direction, respectively, was taken as a result. This example is 7N/mm.

Example 2: the single-component solvent-free hot melt adhesive for the automobile roof comprises the following raw materials in parts by weight: 50 parts of dicyclohexylmethane diisocyanate, 75 parts of polycaprolactone polyol, 10 parts of polyoxypropylene glycol, 2 parts of trimethylolpropane triacrylate, 3 parts of a chain extender, 1 part of a curing agent, 2 parts of polycarbodiimide, 1 part of an adhesion promoter, 0.3 part of a catalyst and 0.2 part of an antioxidant.

The average molecular weight of the polycaprolactone polyol is 3000; the average molecular weight of the polyoxypropylene diol is 3500.

The chain extender is one or a mixture of more of 1, 4-butanediol, 1, 6-hexanediol, glycerol, trimethylolpropane, diethylene glycol, triethylene glycol, neopentyl glycol, sorbitol, diethylaminoethanol, 3 '-dichloro-4, 4' -diaminodiphenylmethane, ethylenediamine, N-dihydroxy (diisopropyl) aniline and hydroquinone-di (beta-hydroxyethyl) ether.

The curing agent comprises one or two of aliphatic amine curing agent and imidazole curing agent;

the aliphatic amine curing agent is one or a mixture of more of ethylenediamine, hexamethylenediamine, diethylenetriamine and triethylene tetramine;

the imidazole curing agent is a closed product prepared by reacting various imidazoles with Toluene Diisocyanate (TDI), isophorone diisocyanate (IPDI), Hexamethylene Diisocyanate (HDI) and diphenylmethane diisocyanate (MDI).

A preparation method of a single-component solvent-free hot melt adhesive for an automobile roof comprises the following steps:

s1: taking 75 parts of polycaprolactone polyol and 10 parts of polyoxypropylene glycol, fully and uniformly mixing, and dehydrating for 3 hours in a vacuum environment at the dehydration temperature of 150 ℃;

s2: cooling the mixture obtained by dehydration in the step S1 to 70 ℃, adding 2 parts of polycarbodiimide, 1 part of curing agent and 1 part of adhesion promoter, and stirring for 8 minutes;

s3: adding 50 parts of dicyclohexylmethane diisocyanate, 2 parts of trimethylolpropane triacrylate, 03 parts of catalyst and 0.2 part of antioxidant into the stirring container in the step S2, preserving the temperature at 70 ℃, and reacting for 45 minutes;

s4: adding 3 parts of chain extender, and continuously stirring for 25 minutes to obtain a hot melt adhesive finished product.

Wherein the antioxidant is irganox 1010.

Wherein the catalyst is organic bismuth.

Wherein the hydrolysis resistant agent refers to polycarbodiimide Stabaxol P200.

Wherein the latent curing agent refers to ketoxime blocked isocyanate curing agent.

Wherein the chain extender is a dimethylolbutyric acid modifier.

Wherein the adhesion promoter is Degussa LTW (an ester compound).

A method for using a single-component solvent-free hot melt adhesive for an automobile roof comprises the steps of applying a hot melt adhesive between a base layer and a bonding material to form a middle layer; wherein the environmental temperature is 20-30 ℃, the humidity is 40-80%, and the surface temperature of the composite material is 20-30 ℃.

Performance evaluation:

the viscosity of the one-component solvent-free hot-melt adhesive of this example was measured using an SNB-AI viscometer, spindle # 27. The single-component solvent-free hot melt adhesive of the embodiment is heated and stirred in an SNB-AI viscometer for 30 minutes, the displayed value is read, and the displayed value of the viscosity is kept unchanged for 20 minutes, namely the measured viscosity of the hot melt adhesive is obtained. The viscosity of the one-component solvent-free hot melt adhesive of this example was 5600mpa.s at 80 ℃.

Determination of the isocyanate group content (NCO%): the single-component solvent-free hot-melt adhesive of this example was reacted for 20 minutes with an excess of di-N-butylamine in N-methylpyrrolidone, and then the NCO% was determined by titration with hydrochloric acid, and the NCO% by weight was determined to be 7.8%.

The maximum load when the backboard sample breaks has different tensile strengths for the backboards with different thicknesses and different materials, and the tensile strength of the general KPK/KPE backboard is not less than 120Mpa longitudinally and not less than 120Mpa transversely. According to the regulation of GB/T13542.2-2009, chapter 11. The test piece is 200mm long and (15 +/-1) mm wide, and five test pieces are taken in the transverse direction and the longitudinal direction respectively. The measurement accuracy of the width of the sample is not less than 0.1 mm. Two marker lines spaced at least 50mm apart are marked in the middle of the specimen and the load is applied at a tensile rate of 100mm/min until the specimen single component fails as an end point. The results were obtained as the median of five test values in the transverse and longitudinal directions, respectively. This example is 161 MPa.

The maximum load when the backboard sample breaks has different tensile strengths for the backboards with different thicknesses and different materials, and the breaking elongation of the general KPK/KPE backboard is more than or equal to 100 percent in the longitudinal direction and more than or equal to 100 percent in the transverse direction. According to the regulation of GB/T13542.2-2009, chapter 11. The test piece is 200mm long and (15 +/-1) mm wide, and five test pieces are taken in the transverse direction and the longitudinal direction respectively. The measurement accuracy of the width of the sample is not less than 0.1 mm. Two marker lines spaced at least 50mm apart are marked in the middle of the specimen and the load is applied at a tensile rate of 100mm/min until the specimen single component fails as an end point. The results were obtained as the median of five test values in the transverse and longitudinal directions, respectively. This example is 170%.

The adhesive strength between the layers of the back plate is tested, and the most common standard is more than or equal to 4N/10 mm. According to the provisions of GB/T2790-1995. The test piece is 200mm long and (15 +/-1) mm wide, and five test pieces are taken in the transverse direction and the longitudinal direction respectively. The width of the test specimen is not less than 0.1mm, and the test specimen tears apart a layer of the composite material (fluorine/PET) along the length direction. The 180 DEG peeling test was carried out at a peeling speed of 100mm/min, and the median of five test values in the transverse direction and the longitudinal direction, respectively, was taken as a result. This example is 8N/mm.

Example 3: the single-component solvent-free hot melt adhesive for the automobile roof comprises the following raw materials in parts by weight: 55 parts of dicyclohexylmethane diisocyanate, 80 parts of polycaprolactone polyol, 15 parts of polyoxypropylene glycol, 3 parts of trimethylolpropane triacrylate, 5 parts of a chain extender, 2 parts of a curing agent, 3 parts of polycarbodiimide, 2 parts of an adhesion promoter, 0.5 part of a catalyst and 0.3 part of an antioxidant.

The average molecular weight of the polycaprolactone polyol is 4000; the average molecular weight of the polyoxypropylene diol is 4000.

The chain extender is one or a mixture of more of 1, 4-butanediol, 1, 6-hexanediol, glycerol, trimethylolpropane, diethylene glycol, triethylene glycol, neopentyl glycol, sorbitol, diethylaminoethanol, 3 '-dichloro-4, 4' -diaminodiphenylmethane, ethylenediamine, N-dihydroxy (diisopropyl) aniline and hydroquinone-di (beta-hydroxyethyl) ether.

The curing agent comprises one or two of aliphatic amine curing agent and imidazole curing agent;

the aliphatic amine curing agent is one or a mixture of more of ethylenediamine, hexamethylenediamine, diethylenetriamine and triethylene tetramine;

the imidazole curing agent is a closed product prepared by reacting various imidazoles with Toluene Diisocyanate (TDI), isophorone diisocyanate (IPDI), Hexamethylene Diisocyanate (HDI) and diphenylmethane diisocyanate (MDI).

A preparation method of a single-component solvent-free hot melt adhesive for an automobile roof comprises the following steps:

s1: taking 80 parts of polycaprolactone polyol and 15 parts of polyoxypropylene glycol, fully and uniformly mixing, and dehydrating for 4 hours in a vacuum environment at the dehydration temperature of 160 ℃;

s2: cooling the mixture obtained by dehydration in the step S1 to 50-90 ℃, adding 3 parts of polycarbodiimide, 2 parts of curing agent and 2 parts of adhesion promoter, and stirring for 10 minutes;

s3: adding 55 parts of dicyclohexylmethane diisocyanate, 3 parts of trimethylolpropane triacrylate, 0.5 part of catalyst and 0.3 part of antioxidant into the stirring container in the step S2, preserving the temperature at 90 ℃, and reacting for 60 minutes;

s4: and adding 5 parts of chain extender, and continuously stirring for 40 minutes to obtain a hot melt adhesive finished product.

Wherein the antioxidant is irganox 1010.

Wherein the catalyst is organic bismuth.

Wherein the hydrolysis resistant agent refers to polycarbodiimide Stabaxol P200.

Wherein the latent curing agent refers to ketoxime blocked isocyanate curing agent.

Wherein the chain extender is a dimethylolbutyric acid modifier.

Wherein the adhesion promoter is Degussa LTW (an ester compound).

A method for using a single-component solvent-free hot melt adhesive for an automobile roof comprises the steps of applying a hot melt adhesive between a base layer and a bonding material to form a middle layer; wherein the environmental temperature is 20-30 ℃, the humidity is 40-80%, and the surface temperature of the composite material is 20-30 ℃.

Performance evaluation:

the viscosity of the one-component solvent-free hot-melt adhesive of this example was measured using an SNB-AI viscometer, spindle # 27. The single-component solvent-free hot melt adhesive of the embodiment is heated and stirred in an SNB-AI viscometer for 30 minutes, the displayed value is read, and the displayed value of the viscosity is kept unchanged for 20 minutes, namely the measured viscosity of the hot melt adhesive is obtained. The one-component, solvent-free hot melt adhesive of this example had a viscosity of 5800mpa.s at 80 ℃.

Determination of the isocyanate group content (NCO%): the single-component solvent-free hot-melt adhesive of this example was reacted for 20 minutes with an excess of di-N-butylamine in N-methylpyrrolidone, and then the NCO% was determined by titration with hydrochloric acid, and the NCO% by weight was determined to be 8.3%.

The maximum load when the backboard sample breaks has different tensile strengths for the backboards with different thicknesses and different materials, and the tensile strength of the general KPK/KPE backboard is not less than 120Mpa longitudinally and not less than 120Mpa transversely. According to the regulation of GB/T13542.2-2009, chapter 11. The test piece is 200mm long and (15 +/-1) mm wide, and five test pieces are taken in the transverse direction and the longitudinal direction respectively. The measurement accuracy of the width of the sample is not less than 0.1 mm. Two marker lines spaced at least 50mm apart are marked in the middle of the specimen and the load is applied at a tensile rate of 100mm/min until the specimen single component fails as an end point. The results were obtained as the median of five test values in the transverse and longitudinal directions, respectively. In this example 159 MPa.

The maximum load when the backboard sample breaks has different tensile strengths for the backboards with different thicknesses and different materials, and the breaking elongation of the general KPK/KPE backboard is more than or equal to 100 percent in the longitudinal direction and more than or equal to 100 percent in the transverse direction. According to the regulation of GB/T13542.2-2009, chapter 11. The test piece is 200mm long and (15 +/-1) mm wide, and five test pieces are taken in the transverse direction and the longitudinal direction respectively. The measurement accuracy of the width of the sample is not less than 0.1 mm. Two marker lines spaced at least 50mm apart are marked in the middle of the specimen and the load is applied at a tensile rate of 100mm/min until the specimen single component fails as an end point. The results were obtained as the median of five test values in the transverse and longitudinal directions, respectively. This example is 165%.

The adhesive strength between the layers of the back plate is tested, and the most common standard is more than or equal to 4N/10 mm. According to the provisions of GB/T2790-1995. The test piece is 200mm long and (15 +/-1) mm wide, and five test pieces are taken in the transverse direction and the longitudinal direction respectively. The width of the test specimen is not less than 0.1mm, and the test specimen tears apart a layer of the composite material (fluorine/PET) along the length direction. The 180 DEG peeling test was carried out at a peeling speed of 100mm/min, and the median of five test values in the transverse direction and the longitudinal direction, respectively, was taken as a result. This example is 7.5N/mm.

By adopting the scheme, organic solvent and double A-class substances are not required to be added, VOC discharge amount can be greatly reduced, pollution of the hot melt adhesive to the environment is effectively improved, and investment of enterprise environment-friendly facilities is reduced, environment-friendly disposal cost is reduced, and potential safety hazard brought to enterprises by solvent storage is avoided.

In addition, the viscosity of the hot melt adhesive prepared from 45-55 parts of dicyclohexylmethane diisocyanate, 70-80 parts of polycaprolactone polyol, 5-15 parts of polyoxypropylene glycol, 1-3 parts of trimethylolpropane triacrylate, 0.1-5 parts of a chain extender, 0.1-2 parts of a curing agent, 0.1-3 parts of polycarbodiimide, 0.1-2 parts of an adhesion promoter, 0.1-0.5 part of a catalyst and 0.1-0.3 part of an antioxidant at 80 ℃ is 5600mpa.s, the NOC% is 7.8% measured according to the weight ratio, the tensile strength is 161MPa, the elongation at break is 170%, and the initial interlayer peeling strength is 8N/mm.

The above embodiments are merely illustrative of the technical ideas and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and not to limit the protection scope of the present invention. All equivalent changes and modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.