Naphthalene-containing polythiol compound as well as preparation method and application thereof

Abstract

The invention discloses a naphthalene-containing polythiol compound and a preparation method and application thereof, the naphthalene-containing polythiol compound has the following structural general formula: # imgabs0 #, and R1, R2, R3 and R4 are respectively and independently selected from one of C1-C5 divalent alkyl groups. The naphthalene-containing polythiol compound is synthesized from the low-cost raw material 2, 7-naphthalene diphenol through multi-step reaction, and the preparation method is simple, low in cost, high in yield and suitable for industrial mass production. More importantly, the naphthalene-containing polythiol compound provided by the invention contains a double-naphthalene structure and four alkyl thiol groups, is liquid at room temperature, is not easy to hydrolyze, and can be directly used as a curing agent for curing a resin composition, so that the low-temperature curing of the resin composition can be realized, and the resin composition can be cured at a high temperature. The mechanical property, the heat resistance and the water resistance of a cured adhesive layer can be effectively improved, and a resin composition formed by taking the epoxy resin as a curing agent has a good application prospect in the aspects of bonding or sealing of electronic components and the like.

Description

Technical Field

[0001] The invention relates to the technical field of organic synthesis and adhesives, and in particular to a naphthalene-containing polythiol compound and a preparation method and application thereof. Background Art

[0002] In recent years, with the development of electronic equipment, electronic circuits need to have better performance to adapt to the complex and changing use environment, which also puts higher requirements on bonding materials. In the assembly and assembly of electronic components, in order to protect the internal integrated circuit chips from the influence of the external environment or to ensure the stability and reliability of the chip operation, regardless of the material of the bonded material, adhesives and sealants with good bonding strength, moisture and heat resistance and high reliability are often required.

[0003] Resin compositions used as adhesives or sealants usually contain resins and curing agents. This is because common resins are generally liquid or semi-solid at room temperature and need to be converted into solid through a curing process to achieve bonding or sealing effects. For example, epoxy resin, one of the common resins, is widely used in the field of electronic packaging due to its various curing methods, high tensile shear strength, high mechanical properties and excellent heat resistance. Epoxy resin can be converted from liquid to solid under the action of a curing agent, but the type of curing agent will directly affect the performance of the resin after curing. Among them, polythiol compounds have multiple thiol groups. Due to their unique chemical structure and reactivity, they can react with epoxy groups or unsaturated groups in the resin at low temperatures to form thioether bonds, forming a three-dimensional network structure with a high cross-linking density, which is conducive to achieving low-temperature curing of the resin composition. Therefore, they have good application prospects in resin systems such as low-temperature curing resin systems, photocurable resin systems, and photothermal dual-curing resin systems. However, the polythiol curing agents reported so far for use in the above-mentioned resin systems generally have the following problems: easy crystallization and poor hydrolysis resistance. The crystallization of the curing agent will reduce the cross-linking density of the adhesive after curing, affecting the bonding strength of the adhesive layer. In addition, the easy hydrolysis of the curing agent will lead to poor moisture and heat aging resistance of the adhesive layer prepared by its curing, which limits its practical application in the field of electronic assembly.

[0004] Based on this, there is an urgent need for a polythiol compound with low crystallization temperature, good storage stability and good hydrolysis resistance, which can be used as a curing agent to prepare a resin composition that can be cured at low temperature, has high bonding strength, good moisture and heat resistance and good waterproof properties, so as to meet the application needs in the field of electronic assembly. Summary of the invention

[0005] To solve the above problems, the present invention provides a naphthalene-containing polythiol compound and a preparation method and application thereof. The naphthalene-containing polythiol compound contains a binaphthalene-type structure and four alkylthiol groups, is liquid at room temperature and is not easily hydrolyzed, and can be directly used as a curing agent for the curing of a resin composition. Not only can the resin composition be cured at low temperature, but the mechanical properties, heat resistance and water resistance of the cured adhesive layer can also be effectively improved. The resin composition composed of the naphthalene-containing polythiol compound as a curing agent has good application prospects in the bonding or sealing of electronic components.

[0006] Specifically, the following technical solutions are provided:

[0007] The first aspect of the present invention provides a naphthalene-containing polythiol compound, wherein the naphthalene-containing polythiol compound has the following general structural formula:

[0008]

[0009] Among them, R 1 , R 2 , R 3 , R 4 Each is independently selected from one of the C1-C5 divalent alkyl groups, for example, -CH2-, -CH2CH2-, -CH2CH2CH2-, -CH(CH3)CH2-, -CH2CH2CH2CH2-, -CH2CH2CH2CH2CH2-, etc., including but not limited to the divalent alkyl groups listed above.

[0010] The second aspect of the present invention provides a method for preparing the naphthalene-containing polythiol compound according to the first aspect, comprising the following steps:

[0011] S1, reacting 2,7-naphthalene diol with the polyformaldehyde shown in formula I in the presence of a first alkaline reagent and a first solvent to obtain a first intermediate product shown in formula II;

[0012] S2, reacting the first intermediate product with a halogenated olefin compound represented by formula III in the presence of a second base reagent, a phase transfer catalyst and a second solvent to obtain a second intermediate product represented by formula IV;

[0013] S3, reacting the second intermediate product with thioacetic acid in the presence of a free radical initiator and a third solvent to obtain a third intermediate product represented by formula V;

[0014] S4, hydrolyzing the third intermediate product with an acid or a base in the presence of a fourth solvent to obtain the naphthalene-containing polythiol compound;

[0015] The structures of the above formula I to formula V are as follows:

[0016]

[0017] Furthermore, in S1, the first alkaline reagent can be selected from one or more of potassium carbonate, sodium carbonate, potassium hydroxide, sodium hydroxide, triethylamine, and p-dimethylaminopyridine.

[0018] Furthermore, in S1, the first solvent is preferably water.

[0019] Furthermore, in S1, the reaction temperature is preferably 40-50°C.

[0020] Furthermore, in S1, part of the 2,7-naphthalenediol and part of the first alkaline reagent are first mixed and reacted for 0.5-1.5 hours, and then the aqueous solution of the polyformaldehyde is added to continue the reaction for 8-24 hours, and finally the remaining part of the 2,7-naphthalenediol and the remaining part of the alkaline reagent are added to carry out condensation reflux reaction for 36-48 hours to obtain the first intermediate product; preferably, the molar ratio of the part of the 2,7-naphthalenediol to the remaining part of the 2,7-naphthalenediol is 1:(1-2), for example, 1:1.5; the molar ratio of the part of the first alkaline reagent to the remaining part of the alkaline reagent is 1:(0.5-1.5), for example, 1:1.

[0021] Further, in S2, the second alkaline reagent can be selected from one or more of potassium carbonate, sodium carbonate, potassium hydroxide, sodium hydroxide, triethylamine, and p-dimethylaminopyridine; in some preferred embodiments, the first alkaline reagent is potassium carbonate, potassium hydroxide or sodium hydroxide.

[0022] Furthermore, in S2, the phase transfer catalyst can be selected from one or more of crown ethers, onium salts, ammonium salts, sulfonium salts, arsenic salts, polyethers, non-cyclic polyethers and tertiary amine catalysts; in some preferred embodiments, the first phase transfer catalyst is 18-crown ether-6, triethylamine or tetrabutylammonium bromide.

[0023] Furthermore, in S2, the second solvent is selected from one or more of acetone, ethyl acetate, tetrahydrofuran, N,N'-dimethylformamide, dichloromethane, dioxane, ethanol, and methanol; in some preferred embodiments, the first solvent is acetone.

[0024] Furthermore, in S2, the reaction temperature is preferably 60-90°C, and the reaction time is preferably 6-15h, for example, stirring the reaction at 70°C for 12h.

[0025] Furthermore, in S2, the reaction is carried out under a protective atmosphere, and the protective atmosphere is nitrogen or an inert gas.

[0026] Furthermore, in S3, the free radical initiator can be selected from one or more of azo, organic peroxide and oxidation-reduction initiators; in some preferred embodiments, the free radical initiator is azobisisobutyronitrile.

[0027] Furthermore, in S3, the third solvent is selected from one or more of acetone, ethyl acetate, tetrahydrofuran, N,N'-dimethylformamide, dichloromethane, dioxane, ethanol, and methanol; in some preferred embodiments, the third solvent is tetrahydrofuran.

[0028] Furthermore, in S3, the reaction temperature is preferably 60-90°C, and the reaction time is preferably 15-25h, for example, stirring the reaction at 65°C for 16h.

[0029] Furthermore, in S3, the reaction is carried out under a protective atmosphere, and the protective atmosphere is nitrogen or an inert gas.

[0030] Furthermore, in S4, the acid is preferably hydrochloric acid and / or sulfuric acid, and the base is preferably caustic soda. Other acids or bases that can be used to hydrolyze the fourth intermediate product may also be used.

[0031] Furthermore, in S4, the fourth solvent may be selected from one or more of acetone, ethyl acetate, tetrahydrofuran, N,N'-dimethylformamide, dichloromethane, dioxane, ethanol, and methanol.

[0032] Furthermore, in S4, the reaction temperature is preferably 55-95° C., and the reaction time is preferably 25-40 h.

[0033] Furthermore, in S4, the reaction is carried out under a protective atmosphere, and the protective atmosphere is nitrogen or an inert gas.

[0034] The third aspect of the present invention provides a resin composition comprising a resin, a curing agent and a curing accelerator; the curing agent is the naphthalene-containing polythiol compound described in the first aspect.

[0035] Furthermore, the resin includes one or more of epoxy resin, photosensitive resin, benzaldehyde compound, olefin compound having carbon-carbon double bond in molecule, and acrylate compound.

[0036] Furthermore, when the resin is an epoxy resin, the curing accelerator is an amine.

[0037] Preferably, the resin composition comprises, by weight, 30-55 parts of epoxy resin, 27-50 parts of naphthalene-containing polythiol compounds, and 1-5 parts of amine curing accelerators.

[0038] Furthermore, when the resin is an epoxy resin and a photosensitive resin, the curing agent accelerator is an amine and a free radical photoinitiator, and the curing accelerator includes an amine and a free radical photoinitiator.

[0039] Preferably, the resin composition comprises, by mass, 15-30 parts of epoxy resin, 15-30 parts of photosensitive resin, 10-25 parts of naphthalene-containing polythiol compound, 1-5 parts of free radical photoinitiator, and 1-5 parts of amine curing accelerator.

[0040] Furthermore, when the resin is a benzaldehyde compound, the curing accelerator is trifluoroacetic acid.

[0041] Preferably, the resin composition comprises, by weight, 30-55 parts of benzaldehyde compounds, 60-115 parts of naphthalene-containing polythiol compounds, and 1-5 parts of trifluoroacetic acid.

[0042] Furthermore, when the resin is an olefin and / or acrylate compound having a carbon-carbon double bond in the molecule, the curing accelerator is a free radical photoinitiator.

[0043] Preferably, the resin composition comprises, by weight, 30-55 parts of resin, 50-100 parts of naphthalene-containing polythiol compounds, and 1-5 parts of free radical photoinitiator.

[0044] Furthermore, the amine curing accelerator includes but is not limited to PN23, and the free radical photoinitiator includes but is not limited to (2,4,6-trimethylbenzoyl) diphenylphosphine oxide, 2,2-dimethoxy-2-phenylacetophenone

[0045] The fourth aspect of the present invention provides a use of the resin composition described in the third aspect in the preparation of an adhesive or a sealant.

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] 1. The present invention provides a naphthalene-containing polythiol compound. The double naphthalene-type structure contained in the compound molecule can not only effectively improve the adhesion between the resin composition containing the naphthalene-containing polythiol compound and the object to be adhered, but also help to improve the flexibility, hydrolysis resistance and aging resistance of the adhesive layer after curing; at the same time, the naphthalene-containing polythiol compound molecule also contains four alkylthiol groups, and the resin composition cured by it has a high crosslinking density, which can effectively improve the mechanical properties and heat resistance of the adhesive layer. In addition, when the naphthalene-containing polythiol compound is used as a curing agent for the resin composition, the resin composition can be quickly cured under low temperature conditions, and the internal stress and shrinkage generated during curing are small, effectively isolating water vapor, which is beneficial to improving the performance and service life of electronic products bonded or sealed by it.

[0048] 2. The naphthalene-containing polythiol compound provided by the present invention is liquid at room temperature, has little odor and low viscosity, and can be directly used as a curing agent for curing the resin composition without being used in combination with other polythiol compounds; and the compound is not easily hydrolyzed, so that the resin composition cured by it has good moisture and heat resistance.

[0049] 3. The present invention uses low-cost 2,7-naphthalenediol as a raw material to prepare naphthalene-containing polythiol compounds through multi-step reactions. The method is simple to operate, highly controllable and has a high yield. It can achieve low-cost preparation of polythiol compounds and is suitable for mass production. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 A physical picture of the naphthalene-containing polythiol compound prepared in Example 1;

[0051] Figure 2 This is the infrared image of the naphthalene-containing polythiol compound prepared in Example 1. DETAILED DESCRIPTION

[0052] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0053] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0054] The sources of some of the raw materials used in the following examples and comparative examples are as follows:

[0055]

[0056]

[0057] Example 1

[0058] This embodiment provides a preparation method of a naphthalene-containing polythiol compound 3,3',3",3"'-((methylenebis(1,2,7-naphthalenetriyl))tetraoxy)tetrakis(1-propanethiol), and the specific preparation method is as follows:

[0059] (1) 16.02 g of 2,7-naphthalene diol (M=160.17, 0.1 mol) was placed in a single-necked flask, 100 mL of water and 4 g of NaOH (0.1 mol) solution were added, and the mixture was reacted at 45° C. for 30 min in an air atmosphere, followed by dropwise addition of 10 mL of 40% aqueous paraformaldehyde solution (1.22 mol / 100 mL, 0.12 mol), and the reaction was continued for 12 h under the same conditions. In addition, 24.03 g (0.15 mol) of 2,7-naphthalene diol and 4 g of NaOH (0.1 mol) were added to the system, condensed and refluxed, and the reaction was continued for 72 h to obtain a crude product. Hydrochloric acid was added dropwise to the crude product to adjust the pH to less than 7. The liquid was spin-dried and then post-processed to obtain the first intermediate product with a yield of 90%.

[0060] (2) 33.24 g of the first intermediate product and 72.6 g of allyl bromide were dissolved in 250 mL of acetone, and then 110.6 g of anhydrous potassium carbonate and 5.2 g of 18-crown ether-6 were added. The mixture was stirred at 70° C. for 12 h under N2 protection. After filtering, the solvent and excess raw materials in the filtrate were removed by reduced pressure distillation. The mixture was washed with water and dried to obtain a second intermediate product with a yield of 94%.

[0061] (3) 49.3 g of the second intermediate product and 45.7 g of thioacetic acid were dissolved in 300 mL of tetrahydrofuran, and 3.3 g of azobisisobutyronitrile was added. The mixture was stirred and reacted at 65° C. for 16 h under N2 protection. After filtering, the solvent and excess raw materials in the filtrate were removed by reduced pressure distillation. The filtrate was washed with water and dried to obtain a third intermediate product with a yield of 80%.

[0062] (4) 79.7 g of the fourth intermediate product and 10 g of concentrated hydrochloric acid were dissolved in 150 mL of tetrahydrofuran and 150 mL of methanol, and the mixture was stirred at 65° C. for 33 h under N2 protection. After filtering, the solvent and excess raw materials in the filtrate were removed by reduced pressure distillation, and the filtrate was washed with water and dried to obtain the naphthalene-containing polythiol compound with a yield of 88%. The naphthalene-containing polythiol compound is a liquid at room temperature. Figure 1 As shown, it is light yellow and has a viscosity of 3.1 Pa·s; its infrared image is as follows Figure 2 shown.

[0063] Example 2

[0064] The present embodiment provides a thermosetting resin composition, which includes the following components in parts by mass: 42 parts of bisphenol A epoxy resin jER828, 38 parts of naphthalene-containing polythiol compounds prepared in Example 1, 3 parts of latent curing accelerator PN23, 1 part of fumed silica QS-10, 1 part of stabilizer triisopropyl borate, and 1 part of silane coupling agent KBM403.

[0065] The above raw materials are mixed uniformly at room temperature, and then subjected to vacuum degassing treatment. The discharged materials are packaged into sealed rubber tubes to obtain a resin composition.

[0066] Example 3

[0067] This embodiment provides a thermosetting resin composition, which is different from Example 2 only in that the mass fraction of bisphenol A epoxy resin jER828 is 30 parts, the mass fraction of naphthalene-type polythiol compound is 27 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0068] Example 4

[0069] This embodiment provides a thermosetting resin composition, which is different from Example 2 only in that the mass fraction of bisphenol A epoxy resin jER828 is 55 parts, the mass fraction of naphthalene-type polythiol compound is 50 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0070] Example 5

[0071] This embodiment provides a thermosetting resin composition, which is different from Example 2 only in that the mass fraction of bisphenol A epoxy resin jER828 is 35 parts, the mass fraction of naphthalene-type polythiol compound is 31 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0072] Example 6

[0073] This embodiment provides a thermosetting resin composition, which is different from Example 2 only in that the mass fraction of bisphenol A epoxy resin jER828 is 50 parts, the mass fraction of naphthalene-type polythiol compound is 45 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0074] Example 7

[0075] This embodiment provides a thermosetting resin composition, which is different from Example 2 only in that the mass fraction of bisphenol A epoxy resin jER828 is 60 parts, the mass fraction of naphthalene-type polythiol compound is 54 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0076] Example 8

[0077] This embodiment provides a thermosetting resin composition, which is different from Example 2 only in that the mass fraction of bisphenol A epoxy resin jER828 is 25 parts, the mass fraction of naphthalene-type polythiol compound is 23 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0078] Example 9

[0079] The present embodiment provides a photocurable resin composition, which includes the following components in parts by mass: 42 parts of triallyl isocyanurate, 74 parts of the naphthalene-containing polythiol compound prepared in Example 1, 2 parts of photoinitiator 2,2-dimethoxy-2-phenylacetophenone, 1 part of fumed silica QS-10, 0.3 parts of inhibitor p-hydroxyanisole, and 1 part of silane coupling agent KBM503.

[0080] The above raw materials are mixed uniformly at room temperature and in the dark, and then subjected to vacuum degassing treatment. The discharged materials are packaged into black or brown sealed rubber tubes to obtain a resin composition.

[0081] Example 10

[0082] This embodiment provides a photocurable resin composition, which is different from Embodiment 9 only in that the mass fraction of triallyl isocyanurate is 30 parts, the mass fraction of the naphthalene-type polythiol compound is 53 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0083] Embodiment 11

[0084] This embodiment provides a photocurable resin composition, which is different from Embodiment 9 only in that the mass fraction of triallyl isocyanurate is 55 parts, the mass fraction of the naphthalene-type polythiol compound is 97 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0085] Example 12

[0086] This embodiment provides a photocurable resin composition, which is different from Embodiment 9 only in that the mass fraction of triallyl isocyanurate is 34 parts, the mass fraction of the naphthalene-type polythiol compound is 60 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0087] Embodiment 13

[0088] This embodiment provides a photocurable resin composition, which is different from Embodiment 9 only in that the mass fraction of triallyl isocyanurate is 51 parts, the mass fraction of the naphthalene-containing polythiol compound is 90 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0089] Embodiment 14

[0090] This embodiment provides a photocurable resin composition, which is different from Embodiment 9 only in that the mass fraction of triallyl isocyanurate is 57 parts, the mass fraction of the naphthalene-type polythiol compound is 102 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0091] Embodiment 15

[0092] This embodiment provides a photocurable resin composition, which is different from Embodiment 9 only in that the mass fraction of triallyl isocyanurate is 28 parts, the mass fraction of the naphthalene-type polythiol compound is 49 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0093] Example 16

[0094] The present embodiment provides a photothermal dual-curing resin composition, which includes the following components in parts by mass: 21 parts of bisphenol A epoxy resin jER828, 21 parts of photosensitive resin tricyclodecane dimethanol diacrylate, 17 parts of naphthalene-containing polythiol compounds prepared in Example 1, 1.5 parts of latent curing accelerator PN23, 1 part of free radical photoinitiator (2,4,6-trimethylbenzoyl) diphenylphosphine oxide, 1 part of fumed silica QS-10, 0.2 parts of stabilizer triisopropyl borate, 0.3 parts of inhibitor p-hydroxyanisole, and 1 part of silane coupling agent Z-6062.

[0095] The above raw materials are mixed uniformly under light-proof and room temperature conditions, and then degassing treatment is performed. The discharged materials are packaged into black or brown sealed rubber tubes to obtain a resin composition.

[0096] Embodiment 17

[0097] This embodiment provides a photothermal dual-curing resin composition, which differs from Example 16 only in that: the mass fraction of bisphenol A epoxy resin jER828 is 15 parts, the mass fraction of tricyclodecane dimethanol diacrylate is 15 parts, the mass fraction of naphthalene-type polythiol compound is 12 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0098] Embodiment 18

[0099] This embodiment provides a photothermal dual-curing resin composition, which differs from Example 16 only in that the mass fraction of bisphenol A epoxy resin jER828 is 28 parts, the mass fraction of tricyclodecane dimethanol diacrylate is 28 parts, the mass fraction of naphthalene-type polythiol compound is 23 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0100] Embodiment 19

[0101] This embodiment provides a photothermal dual-curing resin composition, which differs from Example 16 only in that: the mass fraction of bisphenol A epoxy resin jER828 is 17 parts, the mass fraction of tricyclodecane dimethanol diacrylate is 17 parts, the mass fraction of naphthalene-type polythiol compound is 14 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0102] Embodiment 20

[0103] This embodiment provides a photothermal dual-curing resin composition, which differs from Example 16 only in that: the mass fraction of bisphenol A epoxy resin jER828 is 26 parts, the mass fraction of tricyclodecane dimethanol diacrylate is 26 parts, the mass fraction of naphthalene-type polythiol compound is 21 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0104] Embodiment 21

[0105] This embodiment provides a photothermal dual-curing resin composition, which differs from Example 16 only in that: the mass fraction of bisphenol A epoxy resin jER828 is 11 parts, the mass fraction of tricyclodecane dimethanol diacrylate is 11 parts, the mass fraction of naphthalene-type polythiol compound is 10 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0106] Embodiment 22

[0107] This embodiment provides a photothermal dual-curing resin composition, which differs from Example 16 only in that: the mass fraction of bisphenol A epoxy resin jER828 is 31 parts, the mass fraction of tricyclodecane dimethanol diacrylate is 31 parts, the mass fraction of naphthalene-type polythiol compound is 25 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0108] Embodiment 23

[0109] The present embodiment provides a room temperature curing resin composition, which includes the following components in parts by mass: component A includes 42 parts of 4-hydroxy-3-methoxybenzaldehyde and 3 parts of trifluoroacetic acid, and component B includes 87 parts of the naphthalene-containing polythiol compound prepared in Example 1, 1 part of fumed silica QS-10, and 1 part of silane coupling agent KBM403.

[0110] The raw materials of components A and B are respectively mixed evenly at room temperature, and then subjected to vacuum degassing treatment. The discharged materials are divided and packaged into sealed double tubes A and B to obtain a resin composition.

[0111] Embodiment 24

[0112] This embodiment provides a room temperature curing resin composition, which differs from Example 23 only in that the mass fraction of 4-hydroxy-3-methoxybenzaldehyde is 30 parts, the mass fraction of the naphthalene-type polythiol compound is 62 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0113] Embodiment 25

[0114] This embodiment provides a room temperature curing resin composition, which differs from Example 23 only in that the mass fraction of 4-hydroxy-3-methoxybenzaldehyde is 55 parts, the mass fraction of the naphthalene-type polythiol compound is 114 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0115] Embodiment 26

[0116] This embodiment provides a room temperature curing resin composition, which differs from Example 23 only in that the mass fraction of 4-hydroxy-3-methoxybenzaldehyde is 35 parts, the mass fraction of the naphthalene-type polythiol compound is 73 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0117] Embodiment 27

[0118] This embodiment provides a room temperature curing resin composition, which differs from Example 23 only in that the mass fraction of 4-hydroxy-3-methoxybenzaldehyde is 50 parts, the mass fraction of the naphthalene-type polythiol compound is 104 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0119] Embodiment 28

[0120] This embodiment provides a room temperature curing resin composition, which differs from Example 23 only in that the mass fraction of 4-hydroxy-3-methoxybenzaldehyde is 60 parts, the mass fraction of the naphthalene-type polythiol compound is 124 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0121] Embodiment 29

[0122] This embodiment provides a room temperature curing resin composition, which differs from Example 23 only in that the mass fraction of 4-hydroxy-3-methoxybenzaldehyde is 25 parts, the mass fraction of the naphthalene-type polythiol compound is 52 parts, and the rest are the same, and the corresponding resin composition is prepared.

[0123] Comparative Example 1

[0124] This comparative example provides a thermosetting resin composition, which is different from Example 2 only in that an equal amount of commercial polythiol curing agent pentaerythritol tetrakis (3-mercaptopropionate) is used to replace the naphthalene-containing polythiol compound, and the rest is the same to prepare a resin composition.

[0125] Comparative Example 2

[0126] This comparative example provides a photocurable resin composition, which is different from Example 9 only in that an equal amount of commercial polythiol curing agent pentaerythritol tetrakis (3-mercaptopropionate) is used to replace the naphthalene-containing polythiol compound, and the rest are the same to prepare a resin composition.

[0127] Comparative Example 3

[0128] This comparative example provides a photothermal dual-curing resin composition, which differs from Example 16 only in that an equal amount of commercial polythiol curing agent pentaerythritol tetrakis (3-mercaptopropionate) is used to replace the naphthalene-containing polythiol compound, and the rest is the same to prepare a resin composition.

[0129] Comparative Example 4

[0130] This comparative example provides a room temperature curing resin composition, which differs from Example 23 only in that the commercial polythiol curing agent pentaerythritol tetrakis (3-mercaptopropionate) replaces the naphthalene-containing polythiol compound, and the rest is the same to prepare a resin composition.

[0131] Performance Testing

[0132] The performance tests of the resin compositions prepared in the above Examples 2-29 and Comparative Examples 1-4 were carried out as follows:

[0133] Curing conditions:

[0134] The resin compositions prepared in Examples 2-8 and Comparative Example 1 were squeezed out from a rubber hose using a dispensing machine and then cured at 80° C. for 60 minutes to obtain cured samples.

[0135] The resin compositions prepared in Examples 9-15 and Comparative Example 2 were squeezed out from a rubber tube using a dispensing machine, and then exposed to ultraviolet light (wavelength 365 nm, light intensity 1000 mW / cm 2 ) Radiation curing for 15 seconds to obtain a cured sample.

[0136] The resin compositions prepared in Examples 16-22 and Comparative Example 3 were squeezed out from a rubber tube using a dispensing machine and first exposed to ultraviolet light (wavelength 365 nm, light intensity 1000 mW / cm 2 ) radiation curing for 5 seconds and then curing at 80°C for 60 minutes to obtain a cured sample.

[0137] The resin compositions prepared in Examples 23-29 and Comparative Example 4 were extruded from double-tube packages using a dispensing machine, mixed in a static mixer, and then cured at room temperature for 24 hours to obtain cured samples.

[0138] (1) Glass transition temperature (°C): The test was performed using a Q-800 dynamic mechanical analysis tester (DMA) from TA Instruments, USA. The resin compositions prepared in the above embodiments and comparative examples were completely cured to form 50 mm × 10 mm × 1 mm strips. The multi-frequency-stress mode was used. The test temperature range was 30 to 150°C. The heating rate was 3°C / min. Nitrogen protection was used during the test. The test frequency was 1 Hz. The glass transition temperature T of the resin composition after curing was determined. g (℃).

[0139] (2) Bond strength (MPa): The resin compositions prepared in the above embodiments and comparative examples were coated on stainless steel sheets to prepare test samples. The bonding area was 12.5 mm×25 mm, and the thickness of the adhesive layer was 0.1 mm. The test samples were cured respectively, and then the completely cured samples were pulled apart in opposite directions using a universal testing machine and tested at an ambient temperature of 25°C. The measured force values ​​were recorded as strength (MPa). The cured samples were subjected to heating and humidification conditions of 85°C / 85%RH / 1000h, and the shear bond strength (MPa) of the samples was tested again at an ambient temperature of 25°C using a universal testing machine and recorded.

[0140] (3) Tensile strength (MPa): The resin compositions prepared in the above examples and comparative examples were respectively made into dumbbell-shaped samples, and test strips were made according to GB / T 1040.2-2006, and the test strips were 5B standard dumbbell-shaped test strips. The test samples were then cured, and then the fully cured samples were subjected to external forces in opposite directions using a universal testing machine. Five test strips were tested as a group, and the tensile speed was 5 mm / min. The measured sample destructive force values ​​were recorded in strength (MPa).

[0141] (4) Chemical resistance: The resin compositions prepared in the above examples and comparative examples were respectively made into block samples to prepare test samples. The test samples were then cured, and 40 mg of the completely cured samples were placed in a 10 wt % sodium hydroxide aqueous solution and soaked at 80° C. for 48 h. The samples were taken out and dried and weighed to calculate the mass loss rate (%).

[0142] The above test results are shown in Table 1 below:

[0143] Table 1

[0144]

[0145]

[0146] As can be seen from Table 1, compared with the different resin composition systems prepared by using commercially available pentaerythritol tetrakis (3-mercaptopropionate) as a curing agent in Comparative Examples 1-4, the resin compositions prepared using the naphthalene-type polythiol compound prepared in Example 1 as a curing agent (Examples 2, 9, 16, and 24) have significantly better bonding strength, tensile strength, and chemical resistance after curing, and exhibit better resistance to moisture and heat, and can be used as adhesives or sealants in the bonding or sealing of electronic components, which is beneficial to improving the performance and reliability of electronic products.

[0147] The above-described embodiments are only preferred embodiments for fully illustrating the present invention, and the protection scope of the present invention is not limited thereto. Equivalent substitutions or changes made by those skilled in the art based on the present invention are within the protection scope of the present invention. The protection scope of the present invention shall be subject to the claims.

Claims

1. A naphthalene-containing polythiol compound, characterized in that: The naphthalene-containing polythiol compound has the following general structural formula: Among them, R 1 , R 2 , R 3 , R 4 Each is independently selected from one of C1-C5 divalent alkyl groups.

2. A method for preparing a naphthalene-containing polythiol compound according to claim 1, characterized in that: The following steps are involved: S1, reacting 2,7-naphthalene diol with the polyformaldehyde shown in formula I in the presence of a first alkaline reagent and a first solvent to obtain a first intermediate product shown in formula II; S2, reacting the first intermediate product with a halogenated olefin compound represented by formula III in the presence of a second base reagent, a phase transfer catalyst and a second solvent to obtain a second intermediate product represented by formula IV; S3, reacting the second intermediate product with thioacetic acid in the presence of a free radical initiator and a third solvent to obtain a third intermediate product represented by formula V; S4, hydrolyzing the third intermediate product with an acid or a base in the presence of a fourth solvent to obtain the naphthalene-containing polythiol compound; The structures of the above formula I to formula V are as follows:

3. The preparation method according to claim 2, characterized in that: S1 contains at least one of the following features: (1) the first alkaline reagent is selected from one or more of potassium carbonate, sodium carbonate, potassium hydroxide, sodium hydroxide, triethylamine, and p-dimethylaminopyridine; (2) The first solvent is water; (3) The reaction temperature is 40-50°C; (4) Mixing part of 2,7-naphthalenediol and part of the first alkaline reagent for reaction for 0.5-1.5 hours, then adding the aqueous solution of polyformaldehyde to continue the reaction for 8-24 hours, and finally adding the remaining part of 2,7-naphthalenediol and the remaining part of the alkaline reagent to condense and reflux for 36-84 hours to obtain the first intermediate product.

4. The preparation method according to claim 2, characterized in that: S2 contains at least one of the following features: (1) the second alkaline reagent is selected from one or more of potassium carbonate, sodium carbonate, potassium hydroxide, sodium hydroxide, triethylamine, and p-dimethylaminopyridine; (2) the phase transfer catalyst is selected from one or more of crown ethers, onium salts, ammonium salts, sulfonium salts, arsenic salts, polyethers, acyclic polyethers and tertiary amine catalysts; (3) the second solvent is selected from one or more of acetone, ethyl acetate, tetrahydrofuran, N,N'-dimethylformamide, dichloromethane, dioxane, ethanol, and methanol; (4) The reaction temperature is 60-90°C and the reaction time is 6-15h; (5) The reaction is carried out under a protective atmosphere, which is nitrogen or an inert gas.

5. The preparation method according to claim 2, characterized in that: S3 contains at least one of the following characteristics: (1) The free radical initiator is selected from one or more of azo initiators, organic peroxide initiators and redox initiators; (2) the third solvent is selected from one or more of acetone, ethyl acetate, tetrahydrofuran, N,N'-dimethylformamide, dichloromethane, dioxane, ethanol, and methanol; (3) The reaction temperature is 60-90°C and the reaction time is 15-25h; (4) The reaction is carried out under a protective atmosphere, which is nitrogen or an inert gas.

6. The preparation method according to claim 2, characterized in that: S4 contains at least one of the following features: (1) The acid is hydrochloric acid and / or sulfuric acid, and the alkali is caustic soda; (2) the fourth solvent is selected from one or more of acetone, ethyl acetate, tetrahydrofuran, N,N'-dimethylformamide, dichloromethane, dioxane, ethanol, and methanol; (3) The reaction temperature is 55-95°C and the reaction time is 25-40h; (4) The reaction is carried out under a protective atmosphere, which is nitrogen or an inert gas.

7. A resin composition, characterized in that It comprises a resin, a curing agent and a curing accelerator; the curing agent is the naphthalene-containing polythiol compound according to claim 1.

8. The resin composition according to claim 7, characterized in that The resin includes one or more of epoxy resin, photosensitive resin, benzaldehyde compound, olefin compound with carbon-carbon double bond in molecule, and acrylate compound.

9. The resin composition according to claim 8, characterized in that When the resin is an epoxy resin, the curing accelerator is an amine, and the resin composition comprises, by weight, 30-55 parts of epoxy resin, 27-50 parts of naphthalene-containing polythiol compounds, and 1-5 parts of amine curing accelerator; When the resin is an epoxy resin and a photosensitive resin, the curing agent accelerator is an amine and a free photoinitiator, and the curing accelerator comprises an amine and a free radical photoinitiator. The resin composition comprises, by weight, 15-30 parts of epoxy resin, 15-30 parts of photosensitive resin, 10-25 parts of naphthalene-containing polythiol compound, 1-5 parts of free radical photoinitiator, and 1-5 parts of amine curing accelerator; When the resin is a benzaldehyde compound, the curing accelerator is trifluoroacetic acid, and the resin composition comprises 30-55 parts of benzaldehyde compounds, 60-115 parts of naphthalene-containing polythiol compounds, and 1-5 parts of trifluoroacetic acid by weight; When the resin is an olefin and / or acrylate compound having a carbon-carbon double bond in the molecule, the curing accelerator is a free radical photoinitiator. The resin composition comprises, by weight, 30-55 parts of resin, 50-100 parts of naphthalene-containing polythiol compounds, and 1-5 parts of free radical photoinitiator.

10. Use of the resin composition according to any one of claims 7 to 9 in the preparation of an adhesive or a sealant.

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