A maleic anhydride based ultraviolet light debonding glue and a preparation method thereof

Abstract

This invention proposes a UV-curable adhesive based on maleic anhydride and its preparation method. The UV-curable adhesive comprises a pentylene glycol-maleic anhydride-glycidyl methacrylate prepolymer, isophorone diisocyanate, a catalyst, a chain extender, and a photoinitiator. The invention introduces the pentylene glycol-maleic anhydride-glycidyl methacrylate prepolymer into the UV-curable adhesive, with an ester group content of 57.5%, which is beneficial for improving the adhesive's adhesion. Maleic anhydride is structurally susceptible to nucleophilic attacks, undergoing nucleophilic addition reactions, and can be synthesized from biomass raw materials such as furfural and 5-hydroxymethylfurfural. The UV-curable adhesive exhibits a 180° peel strength of 25.77 N / 25 mm before UV irradiation, demonstrating excellent adhesion performance. No multifunctional crosslinkable monomers are required. Under UV irradiation, the double bonds undergo crosslinking, and the 180° peel strength decreases to 0.63–0.88 N / 25 mm. The UV-resistant adhesive prepared by this invention is easy to peel off under UV light and leaves no residue.

Description

Technical Field

[0001] This invention belongs to the field of adhesive technology, and specifically relates to a UV-curing adhesive based on maleic anhydride and its preparation method. Background Technology

[0002] Ultraviolet (UV) light-reducing adhesives, as a novel type of adhesive material, are widely used in the semiconductor wafer manufacturing industry. However, wafers are prone to warping and breakage during processing, leading to processing difficulties. Therefore, UV-reducing adhesives must meet the following two conditions: first, they must have good adhesion during processing; and second, their adhesion must significantly decrease after processing.

[0003] Existing anti-tack adhesives are mainly prepared using acrylates as raw materials, with the addition of multifunctional crosslinkable monomers, enabling them to form a network structure after ultraviolet irradiation, thus achieving the anti-tack effect. However, this also results in poor adhesion before ultraviolet irradiation and residual adhesive on the wafer surface after ultraviolet irradiation, failing to effectively complete the anti-tack task during processing. Summary of the Invention

[0004] To address the problems of commonly used acrylate-based anti-tack adhesives requiring the addition of multifunctional crosslinkable monomers, and their poor anti-tack effect and high residue after ultraviolet irradiation, this invention provides a maleic anhydride-based ultraviolet anti-tack adhesive, and also provides a method for preparing the maleic anhydride-based ultraviolet anti-tack adhesive.

[0005] The structural formula of a UV-curable adhesive based on maleic anhydride is as follows:

[0006]

[0007] The structure of R1 is as follows:

[0008]

[0009] The R2 structure is as follows:

[0010] The UV-resistant adhesive has a peel strength of 23.06–25.77 N / 25 mm at 180° before UV irradiation and a peel strength of 0.63–0.88 N / 25 mm at 180° after UV irradiation.

[0011] The preparation steps of a UV-cured anti-tack adhesive based on maleic anhydride are as follows:

[0012] (1) Preparation of carboxyl-terminated pentanediol-maleic anhydride trimer

[0013] Pentylene glycol and maleic anhydride were dissolved in solvent A at a molar ratio of 1:1.8-2.2. The amount of solvent A was 4-7 times the sum of the masses of pentylene glycol and maleic anhydride. Nitrogen gas was introduced for protection, and the reaction was carried out at 70-100℃ for 3-5 hours. Solvent A was removed by rotary evaporation, and the mixture was washed once with deionized water and dried at 80℃ for 12 hours in a constant temperature oven to obtain the carboxyl-terminated pentylene glycol-maleic anhydride trimer.

[0014] (2) Preparation of pentamer prepolymer

[0015] The carboxyl-terminated pentanediol-maleic anhydride trimer and glycidyl methacrylate were dissolved in solvent A at a molar ratio of 1:2 to 2.4. The amount of solvent A was 4 to 7 times the total mass of the carboxyl-terminated pentanediol-maleic anhydride trimer and glycidyl methacrylate. Catalyst A was added at an amount of 1% to 4% of the mass of the carboxyl-terminated pentanediol-maleic anhydride trimer. Under nitrogen protection, the reaction was carried out at a temperature of 110℃ to 130℃ for 3 to 4 hours. Solvent A was removed by rotary evaporation. The product was washed once with deionized water and once with anhydrous ethanol. The product was then dried in a constant temperature oven at 80℃ for 12 hours to obtain the pentamer prepolymer of pentanediol-maleic anhydride-glycidyl methacrylate.

[0016] (3) Preparation of UV light anti-adhesive (3.1) Dissolve the pentamer prepolymer and isophorone diisocyanate in ethyl acetate at a molar ratio of 1:1.1 to 1.5. The amount of ethyl acetate is 4 to 7 times the total mass of the pentamer prepolymer and isophorone diisocyanate. Add catalyst B at 1% to 2% of the mass of the pentamer prepolymer, purge with nitrogen for protection, and react at 60 to 80°C for 3 to 5 hours.

[0017] Catalyst B is an organotin compound or an alcohol compound.

[0018] (3.2) Add chain extender at 5% to 15% of the mass of pentamer prepolymer, purge with nitrogen, and react at 60 to 80°C for 3 to 5 hours; remove most of the solvent ethyl acetate by rotary evaporation to obtain the base adhesive;

[0019] The chain extender is a small molecule diol.

[0020] (3.3) Cool the base adhesive to room temperature, add photoinitiator to the base adhesive at a rate of 2% to 6% of the mass of the pentamer prepolymer, stir for 1 hour, and obtain a UV light-reducing adhesive based on maleic anhydride.

[0021] The initiator is a free radical photoinitiator.

[0022] Further technical solutions are as follows:

[0023] In step (1), solvent A is one of toluene, xylene, and N,N-dimethylformamide.

[0024] In step (2), the catalyst A is one of aluminum acetylacetonate, zinc acetylacetonate, and triethylamine.

[0025] In step (3.1), the catalyst B is one of dibutyltin dilaurate, stannous octoate, and triethanolamine.

[0026] In step (3.2), the chain extender is one of cis-2-buten-1,4-diol, 1,4-butanediol, or 1,6-hexanediol.

[0027] In step (3.3), the photoinitiator is one of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, 1-hydroxycyclohexylphenyl ketone, or 2-hydroxy-methylphenylpropane-1-one.

[0028] The beneficial technical effects of this invention are reflected in the following aspects:

[0029] 1. This invention introduces a pentylene glycol-maleic anhydride-glycidyl methacrylate prepolymer, which exhibits excellent adhesion properties. Maleic anhydride is susceptible to nucleophilic addition reactions, reacting with pentylene glycol under catalysis to form a carboxyl-terminated pentylene glycol-maleic anhydride trimer. This trimer contains two carboxyl groups, two double bonds, and two ester groups. After reacting with glycidyl methacrylate to form a pentamer, the terminal carboxyl groups are converted to terminal hydroxyl groups, and the double bond density increases. The pentylene glycol-maleic anhydride-glycidyl methacrylate pentamer prepolymer, reacted with isophorone diisocyanate to prepare a maleic anhydride-based UV-curing adhesive, eliminating the need for multifunctional crosslinkable monomers in the preparation process. Before UV irradiation, the 180° peel strength can reach 23.06–25.77 N / 25 mm; however, under UV irradiation, the double bonds cross-link, and the 180° peel strength can be reduced to 0.63–0.88 N / 25 mm, showing a significant anti-adhesion effect.

[0030] 2. The UV light-curing adhesive prepared by this invention does not contain any small molecule active diluents, has a simple composition, can quickly complete UV curing and debonding in a short time, has a fast reaction rate and a high degree of cross-linking; under UV irradiation, it can complete the reaction within 1 to 3 minutes, with a fast reaction rate, high conversion rate, and convenient use. Attached Figure Description

[0031] Figure 1 The infrared spectrum is shown for the pentamer prepolymer of pentanediol-maleic anhydride-glycidyl methacrylate prepared in Example 1.

[0032] Figure 2 The image shows a comparison of the 1H NMR spectra of the carboxyl-terminated pentanediol-maleic anhydride trimer and the pentamer prepolymer of pentanediol-maleic anhydride-glycidyl methacrylate prepared in Example 1. Detailed Implementation

[0033] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0034] Example 1

[0035] The preparation steps of a UV-cured anti-tack adhesive based on maleic anhydride are as follows:

[0036] (1) Preparation of carboxyl-terminated pentanediol-maleic anhydride trimer

[0037] The reaction formula for synthesizing carboxyl-terminated pentanediol-maleic anhydride trimer from pentanediol and maleic anhydride is as follows:

[0038]

[0039] The specific preparation steps are as follows:

[0040] 10.41 g (0.1 mol) pentylene glycol and 19.61 g (0.2 mol) maleic anhydride were dissolved in 150 g xylene at a molar ratio of 1:2. The mixture was then purged with nitrogen and reacted at 100 °C for 3 h. After the reaction was complete, the solvent xylene was evaporated by rotary evaporation. The mixture was washed once with deionized water and dried at 80 °C for 12 h to obtain the carboxyl-terminated pentylene glycol-maleic anhydride trimer.

[0041] (2) Preparation of pentamer prepolymer

[0042] The reaction formula for synthesizing the pentanediol-maleic anhydride-glycidyl methacrylate pentameric prepolymer by reacting the carboxyl-terminated pentanediol-maleic anhydride trimer with glycidyl methacrylate is as follows:

[0043]

[0044] The specific preparation steps are as follows:

[0045] 30 g (0.1 mol) of carboxyl-terminated pentylene glycol-maleic anhydride trimer and 28.43 g (0.2 mol) of glycidyl methacrylate were dissolved in 292 g xylene at a molar ratio of 1:2, and 0.3 g of aluminum acetylacetonate was added. Under nitrogen protection, the reaction was carried out at 130 °C for 3 h. After the reaction was completed, the solvent xylene was evaporated by rotary evaporation. The product was washed once with deionized water and once with anhydrous ethanol, and dried at 80 °C for 12 h to obtain the pentamer prepolymer of pentylene glycol-maleic anhydride-glycidyl methacrylate.

[0046] The infrared spectrum of the prepared pentamer prepolymer is shown below. Figure 1 As shown; the comparison of the 1H NMR spectra of the trimer and pentamer prepolymers is as follows. Figure 2 As shown, the disappearance of the carboxyl hydrogen peak at 12.96 ppm in the pentamer prepolymer proves that the trimer reacted successfully with glycidyl methacrylate.

[0047] (3) Preparation of UV light anti-tack adhesive

[0048] The reaction formula for preparing UV-sensitive adhesives is as follows:

[0049]

[0050] The specific preparation steps are as follows:

[0051] (3.1) Dissolve 52.61 g (0.09 mol) of pentamer prepolymer and 28.01 g (0.126 mol) of isophorone diisocyanate in 320 g of ethyl acetate at a molar ratio of 1:1.4; add 0.526 g of dibutyltin dilaurate, purge with nitrogen, and react at 60 °C for 3 h.

[0052] (3.2) Add 5.26g of cis-2-butene-1,4-diol as a chain extender to carry out the chain extension reaction. Nitrogen gas is introduced and the reaction is carried out at 60°C for 3 hours to end the reaction. Most of the solvent is evaporated to obtain the base adhesive.

[0053] (3.3) Cool the base adhesive to room temperature, add 1.578g of photoinitiator diphenyl (2,4,6-trimethylbenzoyl)phosphine oxide to the base adhesive, stir for 1h to obtain a UV light-reducing adhesive based on maleic anhydride.

[0054] The UV-resistant adhesive prepared in Example 1 has a peel strength of 25.77 N / 25 mm at 180° before UV irradiation and a peel strength of 0.88 N / 25 mm at 180° after UV irradiation.

[0055] Example 2

[0056] The preparation steps of a UV-cured anti-tack adhesive based on maleic anhydride are as follows:

[0057] (1) Preparation of carboxyl-terminated pentanediol-maleic anhydride trimer

[0058] The specific steps are as follows:

[0059] 10.41 g (0.1 mol) pentanediol and 21.57 g (0.22 mol) maleic anhydride were dissolved in 160 g N,N-dimethylformamide at a molar ratio of 1:2.2. The mixture was protected by nitrogen gas and reacted at 90 °C for 3 h. After the reaction was completed, the solvent N,N-dimethylformamide was rotary evaporated. The mixture was washed once with deionized water and dried at 80 °C for 12 h to obtain the carboxyl-terminated pentanediol-maleic anhydride trimer.

[0060] (2) Preparation of pentamer prepolymer

[0061] The specific steps are as follows:

[0062] 30 g (0.1 mol) of carboxyl-terminated pentylene glycol-maleic anhydride trimer and 29.85 g (0.21 mol) of glycidyl methacrylate were dissolved in 240 g of N,N-dimethylformamide at a molar ratio of 1:2.1. 0.6 g of triethylamine was added, and the mixture was purged with nitrogen and reacted at 110 °C for 4 h. After the reaction was completed, the solvent N,N-dimethylformamide was rotary evaporated. The mixture was washed once with deionized water and once with anhydrous ethanol, and dried at 80 °C for 12 h to obtain the pentamer prepolymer of pentylene glycol-maleic anhydride-glycidyl methacrylate.

[0063] (3) Preparation of UV light anti-tack adhesive

[0064] The specific steps are as follows:

[0065] (3.1) At a molar ratio of 1:1.3, 46.77 g (0.08 mol) of pentamer prepolymer and 23.12 g (0.104 mol) of isophorone diisocyanate were dissolved in 350 g of ethyl acetate, 0.701 g of stannous octoate was added, nitrogen gas was introduced, and the reaction was carried out at 70 °C for 3 h.

[0066] (3.2) Add 4.67g of 1,4-butanediol as a chain extender to carry out the chain extension reaction. Nitrogen gas is introduced and the reaction is carried out at 70℃ for 3h to end the reaction. Most of the solvent is evaporated to obtain the base adhesive.

[0067] (3.3) Cool the base adhesive to room temperature, add 1.403g of 1-hydroxycyclohexylphenyl ketone to the base adhesive, stir for 1h to obtain a UV-resistant adhesive based on maleic anhydride.

[0068] The UV-resistant adhesive prepared in Example 2 has a peel strength of 23.06 N / 25 mm at 180° before UV irradiation and a peel strength of 0.72 N / 25 mm at 180° after UV irradiation.

[0069] Example 3

[0070] The preparation steps of a UV-cured anti-tack adhesive based on maleic anhydride are as follows:

[0071] (1) Preparation of carboxyl-terminated pentanediol-maleic anhydride trimer

[0072] The specific steps are as follows:

[0073] Weigh 10.41 g (0.1 mol) pentanediol and 20.59 g (0.21 mol) maleic anhydride in a molar ratio of 1:2.1 and dissolve them in 155 g toluene. Under nitrogen protection, react at 100 °C for 4 h. After the reaction is complete, evaporate the solvent N,N-dimethylformamide by rotary evaporation. Wash once with deionized water and dry in a constant temperature oven at 80 °C for 12 h to obtain the carboxyl-terminated pentanediol-maleic anhydride trimer.

[0074] (2) Preparation of pentamer prepolymer

[0075] The specific steps are as follows:

[0076] 30 g (0.1 mol) of carboxyl-terminated pentylene glycol-maleic anhydride trimer, 32.69 g (0.23 mol) of glycidyl methacrylate, and 0.9 g of zinc acetylacetonate were dissolved in 250 g of toluene. Under nitrogen protection, the mixture was reacted at 120 °C for 4 h. After the reaction was completed, the solvent toluene was evaporated by rotary evaporation. The mixture was washed once with deionized water and once with anhydrous ethanol, and then dried at 80 °C for 12 h to obtain the pentamer prepolymer of pentylene glycol-maleic anhydride-glycidyl methacrylate.

[0077] (3) Preparation of UV light anti-tack adhesive

[0078] The specific steps are as follows:

[0079] (3.1)) Dissolve 58.46 g (0.1 mol) of pentamer prepolymer, 26.68 g (0.12 mol) of isophorone diisocyanate and 0.584 g of triethanolamine in 425 g of ethyl acetate, purge with nitrogen gas, and react at 60 °C for 3 h.

[0080] (3.2) Add 4.38g of 1,6-hexanediol as a chain extender to carry out the chain extension reaction. Purge with nitrogen gas and react at 60°C for 3 hours to end the reaction. Rotary evaporate most of the solvent to obtain the base gel.

[0081] (3.3) Cool to room temperature, add 2.338 g of 2-hydroxy-methylphenylpropane-1-one, stir for 1 h to obtain a UV-resistant adhesive based on maleic anhydride.

[0082] The UV-resistant adhesive prepared in Example 3 has a peel strength of 24.14 N / 25 mm at 180° before UV irradiation and a peel strength of 0.63 N / 25 mm at 180° after UV irradiation.

[0083] The peel strength of the maleic anhydride-based UV-sensitive adhesives prepared in Examples 1-3 is shown in Table 1. The test method is based on the national standard GB / T 2792-1998 "Test method for 180° peel strength of pressure-sensitive adhesive tape".

[0084] Table 1. 180° peel strength of UV-cured adhesives in Examples 1-3

[0085]

[0086] As can be seen from Examples 1-3 in Table 1, the maleic anhydride-based UV-curing adhesive of the present invention loses its adhesiveness after UV irradiation and does not leave residual adhesive on the device surface. After UV irradiation, the 180° peel strength of the UV-curing adhesive of the present invention can be as low as 0.63 N / 25 mm, demonstrating a significant anti-adhesion effect and easy peeling. Before UV irradiation, the 180° peel strength of the UV-curing adhesive of the present invention can reach 25.77 N / 25 mm, exhibiting excellent adhesion performance and effectively fixing wafers, etc.

Claims

1. A UV-curing adhesive based on maleic anhydride, characterized in that: The UV-resistant adhesive has a peel strength of 23.06–25.77 N / 25 mm at 180° before UV irradiation and a peel strength of 0.63–0.88 N / 25 mm at 180° after UV irradiation. The preparation steps of the maleic anhydride-based UV-curing adhesive are as follows: (1). Preparation of carboxyl-terminated pentanediol-maleic anhydride trimer Pentylene glycol and maleic anhydride were dissolved in solvent A at a molar ratio of 1:1.8-2.

2. The amount of solvent A was 4-7 times the sum of the masses of pentylene glycol and maleic anhydride. Nitrogen gas was introduced for protection, and the reaction was carried out at 70-100℃ for 3-5 hours. Solvent A was removed by rotary evaporation, and the mixture was washed once with deionized water and dried at 80℃ for 12 hours in a constant temperature oven to obtain the carboxyl-terminated pentylene glycol-maleic anhydride trimer. Solvent A is one of toluene, xylene, and N,N-dimethylformamide; (2). Preparation of pentamer prepolymer Dissolve the terminal carboxyl pentylene glycol-maleic anhydride trimer and glycidyl methacrylate in solvent A at a molar ratio of 1:2 to 2.

4. The amount of solvent A is 4 to 7 times the total mass of the terminal carboxyl pentylene glycol-maleic anhydride trimer and glycidyl methacrylate. Add catalyst A at an amount of 1% to 4% of the mass of the terminal carboxyl pentylene glycol-maleic anhydride trimer. Under nitrogen protection, the reaction was carried out at 110℃~130℃ for 3~4h. Solvent A was removed by rotary evaporation. The product was washed once with deionized water and once with anhydrous ethanol. It was then dried at 80℃ for 12h in a constant temperature oven to obtain the pentamer prepolymer of pentanediol-maleic anhydride-glycidyl methacrylate. The catalyst A is one of aluminum acetylacetonate, zinc acetylacetonate, and triethylamine; (3) Preparation of UV light anti-tack adhesive (3.1) Dissolve the pentameric prepolymer and isophorone diisocyanate in ethyl acetate at a molar ratio of 1:1.1 to 1.

5. The amount of ethyl acetate is 4 to 7 times the total mass of the pentameric prepolymer and isophorone diisocyanate. Add catalyst B at 1% to 2% of the mass of the pentameric prepolymer, purge with nitrogen for protection, and react at 60 to 80°C for 3 to 5 hours. The catalyst B is an organotin compound or an alcohol compound; The catalyst B is one of dibutyltin dilaurate, stannous octoate, and triethanolamine. (3.2) Add chain extender at 5% to 15% of the mass of pentamer prepolymer, purge with nitrogen, and react at 60 to 80°C for 3 to 5 hours; remove most of the solvent ethyl acetate by rotary evaporation to obtain the base adhesive; The chain extender is a small molecule diol; The chain extender is one of cis-2-buten-1,4-diol, 1,4-butanediol, and 1,6-hexanediol; (3.3) Cool the base adhesive to room temperature, add photoinitiator to the base adhesive at a rate of 2% to 6% of the mass of the pentamer prepolymer, stir for 1 hour, and obtain a UV light-reducing adhesive based on maleic anhydride. The initiator is a free radical photoinitiator; The photoinitiator is one of diphenyl (2,4,6-trimethylbenzoyl)phosphine oxide, 1-hydroxycyclohexylphenyl ketone, and 2-hydroxy-methylphenylpropane-1-one.

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