A uv moisture dual-curing adhesive and a preparation method thereof

Abstract

The UV moisture dual-curing glue provided by the application comprises the following raw materials in terms of weight content: 15-35 parts of alkoxyl-terminated 107, 40-60 parts of vinyl silicone oil, 1-10 parts of fumed silica, 1-5 parts of mercaptan polysiloxane, 1-7 parts of moisture curing cross-linking agent, 1-3 parts of tackifier, 0.5-1.5 parts of platinum catalyst, 0.5-2 parts of photoinitiator, and 0.1-1 part of moisture curing catalyst. The UV moisture dual-curing glue provided by the application is convenient to apply, can be quickly cured, can be quickly positioned, has a dry surface after curing, has no anaerobism, and can meet the requirements of irregular workpiece application and curing.

Description

Technical Field

[0001] This invention relates to the field of adhesives, and more particularly to a UV moisture dual-curing adhesive and its preparation method. Background Technology

[0002] UV adhesive, also known as ultraviolet light curing adhesive, photosensitive adhesive, or shadowless adhesive, is a type of adhesive that requires ultraviolet light to cure. Its biggest advantages are: rapid curing, quick positioning, and high work efficiency.

[0003] Its disadvantages are that ultraviolet light has weak penetration into some plastics or semi-transparent materials, and the curing depth is limited; moreover, the geometry of curable products is limited, many applications have shadows at the edges and corners, opaque parts and dead corners that cannot be irradiated by ultraviolet light are not easy to cure, unreacted light-cured resins may produce volatiles, which may corrode the substrate and may also affect the electrical performance of components, causing problems such as application limitations.

[0004] This invention relates to a UV-curing and moisture-curing dual-curing adhesive, primarily developed for irregularly shaped adhesive dots. It cures rapidly under light irradiation, and areas not exposed to light cure after 2-3 days using moisture from the air, expanding the application range of light-curing resins. The UV-curing and moisture-curing dual-curing UV adhesive operates through two independent stages with different reaction principles. One stage involves a UV light reaction, and the other involves a moisture-curing reaction. This allows the UV light to quickly set the system or achieve "surface dryness," while the moisture-curing reaction ensures thorough curing of "shadowed" areas or inner layers, achieving "complete dryness." This two-layer curing expands the application of UV adhesives in opaque media, irregularly shaped substrates, ultra-thick adhesive layers, and colored adhesive layers. Summary of the Invention

[0005] This invention provides a UV moisture dual-curing adhesive and its preparation method. The adhesive prepared by this invention can be fully cured in irregularly shaped applications, which solves some shortcomings of existing UV adhesives.

[0006] The technical solution of the present invention to solve the above problems is as follows: the raw materials contained by weight are as follows: 15-35 parts alkoxy-terminated 107, 40-60 parts vinyl silicone oil, 1-10 parts fumed silica, 1-5 parts mercaptopolysiloxane, 1-7 parts moisture-curing crosslinking agent, 1-3 parts tackifier, 0.5-1.5 parts platinum catalyst, 0.5-2 parts photoinitiator, and 0.1-1 parts moisture-curing catalyst.

[0007] Based on the above technical solution, the present invention can be further improved as follows.

[0008] Furthermore, the alkoxy-terminated 107 is commercially available and has a viscosity of 1000-20000 mPa·s, preferably 1000-10000 mPa·s.

[0009] Furthermore, the vinyl silicone oil has a viscosity of 100–5000 mPa·s, preferably 300–3000 mPa·s, and its structural formula is as follows: (CH2=CH) (CH3)2SiO[(CH3)2SiO] a Si(CH3)2(CH=CH2)or (CH2=CH)(CH3)2SiO[(CH3)2SiO] b [(CH2=CH)(CH3)SiO] c Si(CH3)2(CH2=CH); where a=200~550, b=50~300, c=50~300.

[0010] Furthermore, the fumed silica is preferably hydrophobic fumed silica.

[0011] Furthermore, the moisture-curing crosslinking agent is preferably methyltrimethoxysilane.

[0012] The method for synthesizing the mercaptopolysiloxane is as follows: 177g of deionized water is added to a three-necked flask equipped with a stirrer. The mixture (70g of dimethyldichlorosilane, 50g of mercaptopropylmethyldimethoxysilane, 2.75g of trimethylchlorosilane, and 80g of toluene) is added to a dropping funnel. The mixture is added to the three-necked flask while stirring at a speed of 350 rpm. The addition is completed in 15 minutes. During the addition, the temperature inside the flask is kept not higher than 40°C. After the addition is completed, the temperature is raised to 90°C and kept under reflux for 30 minutes. Transfer the contents of the bottle to a separatory funnel, let it stand, and after phase separation, retain the upper liquid. Wash it three times with 150g of deionized water until the pH reaches 4.5. Transfer the contents to a three-necked flask, add 0.5g of DR2030 acidic catalyst, start heating, and maintain reflux for 1 hour. During this time, remove water through a water separator. After cooling, transfer the liquid material after vacuum filtration to a rotary evaporator. Remove most of the solvent at 80°C, and then continue rotary evaporation at 120°C and 133Pa for 1 hour. The resulting transparent liquid is mercaptopolysiloxane.

[0013] Furthermore, the platinum catalyst is a (trimethyl)methylcyclopentadienyl platinum complex, which is a platinum catalyst that can be activated by UV light with a wavelength of 240-400 nm.

[0014] Furthermore, the tackifier is one or a mixture of 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane.

[0015] Furthermore, the photoinitiator is preferably 2-hydroxy-2-methyl-1-phenyl-1-propanone.

[0016] Furthermore, the moisture-curing catalyst is one or more of organotin compounds, titanate compounds, Lewis acids, and Lewis bases. The present invention preferably uses titanate compounds, such as (2-ethylhexanol)titanium.

[0017] The present invention discloses a method for preparing a UV moisture-curing dual-curing adhesive, comprising: sequentially adding 15-35 parts of alkoxy-terminated 107, 40-60 parts of vinyl silicone oil, 1-10 parts of fumed silica, and 1-5 parts of mercaptopolysiloxane into a double planetary mixer, and stirring and dispersing at 800 rpm for 30 minutes at room temperature; adding 1-7 parts of moisture-curing crosslinking agent and 1-3 parts of tackifier into the mixer, and stirring and dispersing at 500 rpm for 20 minutes while maintaining a vacuum state with a vacuum degree not less than -0.098 MPa; adding 0.5-1.5 parts of platinum catalyst and 0.5-2 parts of photoinitiator into the mixer, and stirring and dispersing at 300 rpm for 10 minutes while maintaining a vacuum state with a vacuum degree not less than -0.098 MPa; and finally adding 0.1-1 parts of moisture-curing catalyst into the mixer, and stirring and dispersing at 300 rpm for 10 minutes while maintaining a vacuum state with a vacuum degree not less than -0.098 MPa. Nitrogen gas sealing and packaging are sufficient.

[0018] The beneficial effects of the present invention are: the UV moisture dual-curing adhesive provided by the present invention is easy to apply, can cure quickly, can be positioned quickly, the surface of the cured adhesive layer is dry and non-anaerobic, and can meet the application and curing requirements of irregular workpieces. Detailed Implementation

[0019] The principles and features of the present invention are described below. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0020] Example 1 15 parts of alkoxy-terminated polymer with a viscosity of 1000 mPa·s and 40 parts of the polymer with the structure (CH2=CH)(CH3)2SiO[(CH3)2SiO] were used. 200Vinyl silicone oil of Si(CH3)2 (CH=CH2), 1 part of fumed silica, and 1 part of mercaptopolysiloxane were sequentially added to a double planetary stirred tank and dispersed at 800 rpm for 30 minutes at room temperature. Then, 1 part of methyltrimethoxysilane and 1 part of 3-glycidyl etheroxypropyltrimethoxysilane were added to the stirred tank and dispersed at 500 rpm for 20 minutes under vacuum (not less than -0.098 MPa). Next, 0.5 parts of (trimethyl)methylcyclopentadienylplatinum complex and 0.5 parts of 2-hydroxy-2-methyl-1-phenyl-1-propanone were added to the stirred tank and dispersed at 300 rpm for 10 minutes under vacuum (not less than -0.098 MPa). Finally, 0.1 parts of (2-ethylhexanol)titanium were added to the stirred tank and dispersed at 300 rpm for 10 minutes under vacuum (not less than -0.098 MPa). Nitrogen gas sealing and packaging are sufficient.

[0021] Example 2 35 parts of alkoxy-terminated polymer with a viscosity of 10000 mPa·s and 107 and 60 parts of the polymer with the structure (CH2=CH)(CH3)2SiO[(CH3)2SiO] were used. 50 [(CH2=CH)(CH3)SiO] 300 Vinyl silicone oil of Si(CH3)2(CH2=CH), 10 parts of fumed silica, and 5 parts of mercaptopolysiloxane were sequentially added to a double planetary stirred tank and dispersed at 800 rpm for 30 minutes at room temperature. Then, 7 parts of methyltrimethoxysilane and 1 part of 3-glycidyl etheroxypropyltriethoxysilane were added to the stirred tank and dispersed at 500 rpm for 20 minutes under vacuum (not less than -0.098 MPa). Next, 1.5 parts of (trimethyl)methylcyclopentadienylplatinum complex and 2 parts of 2-hydroxy-2-methyl-1-phenyl-1-propanone were added to the stirred tank and dispersed at 300 rpm for 10 minutes under vacuum (not less than -0.098 MPa). Finally, 1 part of (2-ethylhexanol)titanium was added to the stirred tank and dispersed at 300 rpm for 10 minutes under vacuum (not less than -0.098 MPa). Nitrogen gas sealing and packaging are sufficient.

[0022] Example 3 25 parts of alkoxy-terminated 107 with a viscosity of 5000 mPa·s and 25 parts with the structure (CH2=CH)(CH3)2SiO[(CH3)2SiO] were used. 550 Vinyl silicone oil of Si(CH3)2 (CH=CH2), 25 parts of which have the structure (CH2=CH)(CH3)2SiO[(CH3)2SiO] 100 [(CH2=CH)(CH3)SiO]100 Vinyl silicone oil of Si(CH3)2(CH2=CH), 5 parts of fumed silica, and 4 parts of mercaptopolysiloxane were sequentially added to a double planetary stirred tank and dispersed at 800 rpm for 30 minutes at room temperature. Then, 4 parts of methyltrimethoxysilane and 2 parts of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane were added to the stirred tank and dispersed at 500 rpm for 20 minutes under vacuum (not less than -0.098 MPa). Next, 1 part of (trimethyl)methylcyclopentadienylplatinum complex and 1 part of 2-hydroxy-2-methyl-1-phenyl-1-propanone were added to the stirred tank and dispersed at 300 rpm for 10 minutes under vacuum (not less than -0.098 MPa). Finally, 0.5 parts of (2-ethylhexanol)titanium were added to the stirred tank and dispersed at 300 rpm for 10 minutes under vacuum (not less than -0.098 MPa). Nitrogen gas sealing and packaging are sufficient.

[0023] Example 4 30 parts of alkoxy-terminated polymer with a viscosity of 4000 mPa·s and 107 and 25 parts of the polymer with the structure (CH2=CH)(CH3)2SiO[(CH3)2SiO] were used. 300 Vinyl silicone oil of Si(CH3)2 (CH=CH2), 30 parts of which have the structure (CH2=CH)(CH3)2SiO[(CH3)2SiO] 300 [(CH2=CH)(CH3)SiO] 50 Vinyl silicone oil of Si(CH3)2(CH2=CH), 4 parts of fumed silica, and 3 parts of mercaptopolysiloxane were sequentially added to a double planetary stirred tank and dispersed at 800 rpm for 30 minutes at room temperature. Then, 5 parts of methyltrimethoxysilane, 1 part of 3-glycidyl etheroxypropyltrimethoxysilane, and 1 part of 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane were added to the stirred tank and dispersed at 500 rpm for 20 minutes under vacuum (not less than -0.098 MPa). Finally, 0.9 parts of (trimethyl...)... The methylcyclopentadienyl platinum complex is prepared by adding 1.1 parts of 2-hydroxy-2-methyl-1-phenyl-1-propanone to a stirred tank and stirring at 300 rpm for 10 minutes while maintaining a vacuum state with a vacuum degree of not less than -0.098 MPa; finally, 0.7 parts of (2-ethylhexanol) titanium are added to the stirred tank and stirred at 300 rpm for 10 minutes while maintaining a vacuum state with a vacuum degree of not less than -0.098 MPa. The mixture is then sealed and packaged under nitrogen.

[0024] Comparative Example 1 30 parts of alkoxy-terminated polymer with a viscosity of 4000 mPa·s and 107 and 25 parts of the polymer with the structure ((CH2=CH)(CH3)2SiO[(CH3)2SiO) were used. 300 Vinyl silicone oil of Si(CH3)2 (CH=CH2), 30 parts of which have the structure (CH2=CH)(CH3)2SiO[(CH3)2SiO] 300 [(CH2=CH)(CH3)SiO] 50 Vinyl silicone oil of Si(CH3)2(CH2=CH), 4 parts of fumed silica, and 3 parts of mercaptopolysiloxane were sequentially added to a double planetary stirred tank and dispersed at 800 rpm for 30 minutes at room temperature. Then, 5 parts of methyltrimethoxysilane were added to the stirred tank and dispersed at 500 rpm for 20 minutes under vacuum (not less than -0.098 MPa). Next, 0.9 parts of (trimethyl)methylcyclopentadienylplatinum complex and 1.1 parts of 2-hydroxy-2-methyl-1-phenyl-1-propanone were added to the stirred tank and dispersed at 300 rpm for 10 minutes under vacuum (not less than -0.098 MPa). Finally, 0.7 parts of (2-ethylhexanol)titanium were added to the stirred tank and dispersed at 300 rpm for 10 minutes under vacuum (not less than -0.098 MPa). The mixture was then sealed and packaged under nitrogen.

[0025] Comparative Example 2 30 parts of alkoxy-terminated polymer with a viscosity of 4000 mPa·s and 107 and 25 parts of the polymer with the structure ((CH2=CH)(CH3)2SiO[(CH3)2SiO) were used. 300 Vinyl silicone oil of Si(CH3)2 (CH=CH2), 30 parts of which have the structure (CH2=CH)(CH3)2SiO[(CH3)2SiO] 300 [(CH2=CH)(CH3)SiO] 50Vinyl silicone oil of Si(CH3)2(CH2=CH), 4 parts of fumed silica, and 3 parts of mercaptopolysiloxane were sequentially added to a double planetary stirred tank and dispersed at 800 rpm for 30 minutes at room temperature. Then, 5 parts of methyltrimethoxysilane were added to the stirred tank and dispersed at 500 rpm for 20 minutes under vacuum (not less than -0.098 MPa). Next, 0.9 parts of 3000 ppm Castel platinum catalyst and 1.1 parts of 2-hydroxy-2-methyl-1-phenyl-1-propanone were added to the stirred tank and dispersed at 300 rpm for 10 minutes under vacuum (not less than -0.098 MPa). Finally, 0.7 parts of (2-ethylhexanol) titanium were added to the stirred tank and dispersed at 300 rpm for 10 minutes under vacuum (not less than -0.098 MPa). The mixture was then sealed and packaged under nitrogen.

[0026] Comparative Example 3 30 parts of alkoxy-terminated polymer with a viscosity of 4000 mPa·s and 107 and 25 parts of the polymer with the structure ((CH2=CH)(CH3)2SiO[(CH3)2SiO) were used. 300 Vinyl silicone oil of Si(CH3)2 (CH=CH2), 30 parts of which have the structure (CH2=CH)(CH3)2SiO[(CH3)2SiO] 300 [(CH2=CH)(CH3)SiO] 50 Vinyl silicone oil of Si(CH3)2(CH2=CH), 4 parts of fumed silica, and 3 parts of mercaptopolysiloxane were sequentially added to a double planetary stirred tank and dispersed at 800 rpm for 30 minutes at room temperature. Then, 5 parts of methyltrimethoxysilane were added to the stirred tank and dispersed at 500 rpm for 20 minutes under vacuum (not less than -0.098 MPa). Next, 0.9 parts of (trimethyl)methylcyclopentadienylplatinum complex and 1.1 parts of 2-hydroxy-2-methyl-1-phenyl-1-propanone were added to the stirred tank and dispersed at 300 rpm for 10 minutes under vacuum (not less than -0.098 MPa). Finally, 0.7 parts of DuPont™ Tyzor® 726 were added to the stirred tank and dispersed at 300 rpm for 10 minutes under vacuum (not less than -0.098 MPa). The mixture was then sealed and packaged under nitrogen.

[0027] The performance of a UV moisture dual-curing adhesive of the present invention was tested through the following experiments.

[0028] Experimental Example 1 Viscosity: Tested according to GB / T 2794-2022.

[0029] UV curing conditions: LED 365nm curing time ≤ 15s; total energy < 5000mJ / cm². 2 .

[0030] Moisture curing conditions: 25℃, relative humidity 50%.

[0031] The test results are compared in the table below: Appearance pale yellow liquid pale yellow liquid pale yellow liquid pale yellow liquid pale yellow liquid pale yellow liquid pale yellow liquid pale yellow liquid Finished product viscosity (mPa·s) 4350 4500 4420 4390 4205 4190 4300 4110 Viscosity (mPa·s) after aging at 50℃ for 7 days 16800 Solidified 15300 33850 12300 11890 13650 12020 Surface condition after curing Sticky dry Non-curing dry dry dry dry dry Color after curing Light yellow and transparent Slightly yellow and transparent pale yellow paste Dark yellow and translucent Slightly yellow and transparent Slightly yellow and transparent Slightly yellow and transparent Slightly yellow and transparent Curing depth, mm 15 seconds 0.89 0.93 Non-curing 0.99 1.05 1.18 1.21 1.09 Curing depth, mm, 3 days 0.91 2.68 Non-curing 2.72 2.78 2.97 2.95 2.88 Cured state after aging, UV / 15S gel state Failure Non-curing Normal curing Normal curing Normal curing Normal curing Normal curing The test results in the table above show that the UV moisture-curing adhesive prepared by this invention has good storage stability. Although the viscosity increases after 50℃ / 7d, it can still cure normally, and the surface of the cured adhesive layer is dry. Comparative Example 1, without epoxy coupling agent tackifier, although its viscosity and curing state are basically the same as the examples, the adhesive has already cured after 50℃ / 7d, resulting in poor storage stability. This demonstrates that adding epoxy coupling agent to the formulation significantly improves the storage stability of the adhesive. Comparative Example 2 used a commonly used Castells platinum catalyst, and the adhesive did not cure. Comparative Example 3 used DuPont™ Tyzor® 726 as a moisture-curing catalyst; although it cured normally, the color after curing was too dark, and the viscosity increased significantly after aging at 50℃ / 7d, indicating poor storage stability. Furthermore, compared with ordinary UV adhesives, the curing depth of Examples 1-4 is significantly better, and the curing depth further increases with time. By comparison, it can be found that the UV-moisture dual-curing adhesive of this invention has good storage stability, light color after curing, and can be well cured by moisture in the air after 2-3 days when applied to places without UV exposure, thus expanding the application field of light-curing resin.

[0032] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A UV-curable moisture-curing adhesive, characterized in that, The composition by weight includes the following raw materials: 15-35 parts alkoxy-terminated 107, 40-60 parts vinyl silicone oil, 1-10 parts fumed silica, 1-5 parts mercaptopolysiloxane, 1-7 parts moisture-curing crosslinking agent, 1-3 parts tackifier, 0.5-1.5 parts platinum catalyst, 0.5-2 parts photoinitiator, and 0.1-1 parts moisture-curing catalyst; The moisture-curing crosslinking agent is methyltrimethoxysilane; The moisture-curing catalyst is (2-ethylhexanol)titanium; The platinum catalyst is (trimethyl)methylcyclopentadienyl platinum complex; the thickener is one or a mixture of 3-glycidyl etheroxypropyltrimethoxysilane, 3-glycidyl etheroxypropyltriethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane.

2. The UV moisture-curing dual-curing adhesive according to claim 1, characterized in that, The fumed silica mentioned is hydrophobic fumed silica.

3. The UV moisture-curing dual-curing adhesive according to claim 1, characterized in that, The method for synthesizing the aforementioned mercaptopolysiloxane is as follows: 177g of deionized water is added to a three-necked flask equipped with a stirrer. A mixture of 70g of dimethyldichlorosilane, 50g of mercaptopropylmethyldimethoxysilane, 2.75g of trimethylchlorosilane, and 80g of toluene is added to a dropping funnel. The mixture is added to the three-necked flask while stirring at 350 rpm, and the addition is completed in 15 minutes. During the addition, the temperature inside the flask is kept below 40°C. After the addition is completed, the temperature is raised to 90°C and kept under reflux for 30 minutes. The contents of the flask are then transferred to a container. The mixture was transferred to a separatory funnel and allowed to stand. After phase separation, the upper liquid was retained and washed three times with 150g of deionized water until the pH reached 4.

5. The mixture was then transferred to a three-necked flask, and 0.5g of DR2030 acidic catalyst was added. Heating was initiated and reflux was maintained for 1 hour, during which water was removed through a water separator. After cooling, the liquid material was transferred to a rotary evaporator after vacuum filtration. Most of the solvent was removed at 80°C, and then rotary evaporation was continued at 120°C and 133Pa for 1 hour. The resulting transparent liquid was mercaptopolysiloxane.

4. The UV moisture-curing dual-curing adhesive according to claim 1, characterized in that, The alkoxy-terminated 107 has a viscosity of 1000–10000 mPa·s; the vinyl silicone oil has a viscosity of 300–3000 mPa·s; and the vinyl silicone oil has the structural formula (CH2=CH)(CH3)2SiO[(CH3)2SiO]. a Si (CH3)2 (CH=CH2) or (CH2=CH) (CH3)2SiO[ (CH3)2SiO] b [(CH2=CH)(CH3)SiO] c Si (CH3)2(CH2=CH); where a=200~550, b=50~300, c=50~300.

5. The UV moisture-curing dual-curing adhesive according to claim 1, characterized in that, The photoinitiator is 2-hydroxy-2-methyl-1-phenyl-1-propanone.