CN113788936A

CN113788936A - Light/heat dual-curing resin composition and preparation method and application thereof

Info

Publication number: CN113788936A
Application number: CN202111232264.6A
Authority: CN
Inventors: 刘晓荣; 林鸿腾; 刘涛; 李帅
Original assignee: Weldtone Xiamen Technology Co Ltd
Current assignee: Weiertong Technology Co ltd
Priority date: 2021-10-22
Filing date: 2021-10-22
Publication date: 2021-12-14
Anticipated expiration: 2041-10-22
Also published as: CN113788936B; WO2023065803A1

Abstract

The invention belongs to the field of adhesives and sealants, and relates to a light/heat dual-curing resin composition, and a preparation method and application thereof. The light/heat dual-curable resin composition contains epoxy resin, polythiol compound, acrylate compound, curing accelerator, photoinitiator, polymerization inhibitor and stabilizer. The light/heat curable resinThe thiol compound adopted in the resin composition is liquid and has no ester bond at room temperature on the basis of not containing the glycoluril group, the smell is small, the corresponding light/heat dual-curing resin composition has no crystal precipitation in storage, the service life is long, the heat resistance and the moisture resistance are good, the resin composition can be rapidly cured, the bonding strength is high after curing, and the resin composition can be used as an adhesive and a sealant.

Description

Light/heat dual-curing resin composition and preparation method and application thereof

Technical Field

The invention belongs to the field of adhesives and sealants, and particularly relates to a light/heat dual-curing resin composition and a preparation method and application thereof.

Background

Based on the recent requirements in the field of electronic circuits for protecting semiconductor elements, making circuits highly centralized and improving connection reliability, epoxy-thiol systems are frequently used in the assembly and mounting of electronic parts to meet the requirements of curing at a lower temperature and having sufficient adhesive strength of adhesives. Compositions employing such systems typically require thermal curing, but are generally not capable of rapid positioning during assembly of precision electronic components. The photocuring adhesive can be cured in a very short time, the energy consumption is low, the curing efficiency is high, and the problems of incomplete curing of a light shielding part and the like exist in practical production application. For example, CN111394028A discloses a light-activated delayed thermosetting adhesive, which contains epoxy resin, polyol, photoinitiator, photosensitizer, thixotropic agent and defoaming agent, and is prepared into a one-component thermosetting adhesive by light activation, but the curing manner of the adhesive is mainly thermosetting, and cannot meet the requirement of fast positioning. CN112521870A discloses an ultraviolet light curing adhesive composition, which contains a UV oligomer, a UV functional monomer, a photoinitiator, an auxiliary agent and a functional filler, wherein the UV oligomer is selected to prepare an ultraviolet light curing adhesive, but the curing is usually incomplete in a light shielding part and cannot reach deep curing. In addition, CN112840004A discloses a resin composition containing a compound having a carbon-carbon double bond group in the molecule, a difunctional thiol compound, an initiator and a radical polymerization inhibitor, wherein although there is no ester bond in the thiol compound used, there still exists an ester bond which may be hydrolyzed in the compound having a carbon-carbon double bond group in the molecule, and since the thiol compound used has only two functional groups, the cured product has flexibility, low degree of crosslinking, poor curing effect, poor barrier property against moisture, and heat resistance, thermal bonding strength and wet-heat hydrolysis resistance are still to be improved.

A light/heat dual curing system is an effective solution to the above problems. For example, CN100404579C adopts a dual-curing system of fast photo-curing positioning and thermal curing, but the curing agent contained in the system has a significant sulfur odor, and the system has low crosslinking degree after curing and poor heat resistance and humidity-resistant hydrolysis resistance, and still cannot meet the increasing demand in the field of electronic assembly. CN111356716A discloses a one-pack composition which is liquid at room temperature, can be fixed by radiation and cured by heat, which uses ester-free tris (3-mercaptopropyl) isocyanurate to improve the hydrolysis resistance of photo-thermal dual-curing resin composition, but such polythiol can emit an unpleasant and strong sulfur odor at room temperature, and the heat resistance of the cured product is also unsatisfactory. In addition, in order to simultaneously impart good moisture resistance and heat resistance to a cured resin, mercaptoalkylglycoluril is currently the mainstream in the industry as a curing agent. For example, patent CN201480064943.9 and JP2015059099A disclose a polythiol curing agent called mercaptoalkyl glycoluril, which has good moisture resistance and heat resistance, but patent CN201680014880.5 proposes that the polythiol curing agent is solid at room temperature, easily precipitates crystals when forming a complex with an epoxy resin, and has a problem that the composition becomes non-uniform, and at this time, it is necessary to use another mercaptoethyl glycoluril compound in combination, thereby liquefying the solid polythiol curing agent, and finally forming a liquid oligomer mixture having disulfide bonds as a curing agent. Furthermore, the mercaptoalkylglycoluril-based curing agents mentioned in CN201480064943.9 risk reducing the storage stability of the one-component low-temperature curing epoxy adhesives. In addition, in the manufacture of the image sensor module, the water absorption rate of the used adhesive is required to be low, so that moisture in the air can be prevented from permeating into the module and interfering with a lens system after the module is bonded, assembled and sealed. However, the water absorption of the conventional dual-curable resin composition is generally high, and it is difficult to satisfy this requirement.

In summary, it is highly desirable to develop a curing agent that is liquid, has good storage stability, low cost and low odor, and to prepare a resin composition that can be cured at low temperature, has low water absorption, excellent heat resistance, good resistance to hydrolysis by heat and humidity, high adhesion strength, and can meet the requirement of fast positioning by using a dual photo/thermal curing mechanism, so as to meet the application requirements of high precision fields such as electronic circuits.

Disclosure of Invention

The first purpose of the present invention is to overcome the defects that the prior polythiol curing agent can not be used to realize the liquid state, good storage stability, low cost and low odor, and the corresponding resin composition can not be simultaneously cured at low temperature, low water absorption, excellent heat resistance, good moisture-heat hydrolysis resistance, high bonding strength and can realize the requirement of quick positioning, and provide a novel light/heat dual-curable resin composition, wherein the polythiol compound used in the resin composition is liquid and has no ester bond at room temperature and small odor on the basis of not containing glycoluril group, the resin composition adopts a low-temperature heat-curable system composed of a diphenylring type ester bond-free polythiol compound with a unique structure and epoxy resin, and a light-curable system composed of an acrylate compound and a photoinitiator, so that the obtained resin composition is a light/heat dual-curable system, no crystal is precipitated in the storage process, the service life is long, and the resin composition realizes quick positioning and low-temperature curing on the basis of ensuring high bonding performance, and ensures low water absorption rate and good heat resistance and wet-heat hydrolysis resistance.

A second object of the present invention is to provide a method for preparing the above photo/thermal dual curable resin composition.

The third object of the present invention is to provide the use of the above photo/thermal dual curable resin composition.

Specifically, the light/heat dual-curable resin composition provided by the invention comprises 20-40 parts by weight of epoxy resin, 10-35 parts by weight of polythiol compound, 20-40 parts by weight of acrylate compound, 1-5 parts by weight of curing accelerator, 0.3-5 parts by weight of photoinitiator, 0.01-3 parts by weight of polymerization inhibitor and 0.1-3 parts by weight of stabilizer; the polythiol compound is represented by the general formula (I):

in the general formula (I), R¹、R²、R³And R⁴Wherein only one is a mercaptoalkoxy group having 2 to 5 carbon atoms, R⁵、R⁶、R⁷And R⁸Wherein only one is a mercaptoalkoxy group having 2 to 5 carbon atoms, R¹、R²、R³、R⁴、R⁵、 R⁶、R⁷And R⁸The remaining six of (A) are each independently selected from one of a hydrogen atom, an alkyl group having 1 to 3 carbon atoms and a lower alkoxy group having 1 to 3 carbon atoms.

In a preferred embodiment, in the polythiol compound represented by the general formula (I), R is¹、R²And R⁴One of them is a mercaptoalkoxy group having 2 to 5 carbon atoms and the other two are both hydrogen atoms, R³And R⁷Each independently selected from a hydrogen atom or a methoxy group, R⁵、R⁶And R⁸One of them is a mercaptoalkoxy group having 2 to 5 carbon atoms and the other two are both hydrogen atoms.

In a preferred embodiment, in the polythiol compound represented by the general formula (I), R is¹And R⁵Are each a hydrogen atom, R³And R⁷Each independently selected from a hydrogen atom or a methoxy group, R²And R⁴One of them is a mercaptoalkoxy group having 2 to 5 carbon atoms and the other is a hydrogen atom, R⁶And R⁸One of them is a mercaptoalkoxy group having 2 to 5 carbon atoms and the other is a hydrogen atom.

In a preferred embodiment, the polysulfides of formula (I)In the alcohol compound, R¹And R⁵Are each a hydrogen atom, R³And R⁷Each independently selected from a hydrogen atom or a methoxy group, and when R is²And R⁶When all are mercapto alkoxy groups having 2 to 5 carbon atoms, R⁴And R⁸Are each a hydrogen atom; when R is⁴And R⁸When all are mercapto alkoxy groups having 2 to 5 carbon atoms, R²And R⁶Are each a hydrogen atom; when R is⁴And R⁶When all are mercapto alkoxy groups having 2 to 5 carbon atoms, R²And R⁸Are each a hydrogen atom; when R is²And R⁸When all are mercapto alkoxy groups having 2 to 5 carbon atoms, R⁴And R⁶Are all hydrogen atoms.

In a preferred embodiment, the polythiol compound is prepared by a process comprising the steps of:

the method comprises the following steps: carrying out substitution reaction on a biphenol compound represented by a general formula (II) and a halogenated compound represented by a general formula (III) in the presence of a phase transfer catalyst under an alkaline condition, and purifying to obtain a liquid colorless or light yellow first intermediate product;

step two: carrying out free radical addition reaction on the first intermediate product and thioacetic acid in the presence of a free radical initiator, and purifying to obtain a liquid colorless or light yellow second intermediate product;

step three: carrying out hydrolysis reaction on the second intermediate product, and purifying to obtain a colorless or light yellow viscous liquid product, namely the polythiol compound;

in the general formula (II), R⁹、R¹⁰、R¹¹And R¹²In which only one is hydroxy, R¹³、R¹⁴、R¹⁵And R¹⁶In which only one is hydroxy, R⁹、R¹⁰、R¹¹、R¹²、R¹³、R¹⁴、R¹⁵And R¹⁶The remaining six of the groups are respectively and independently selected from one of hydrogen atoms, alkyl groups with 1-3 carbon atoms and alkoxy groups with 1-3 carbon atoms;

in the general formula (III), X represents chlorine or bromine, and m is 0, 1, 2 or 3.

In a preferred embodiment, in the step one, the substitution reaction is carried out by dissolving the biphenol compound represented by the general formula (ii) in an organic solvent, adding alkali to provide alkaline conditions, adding a phase transfer catalyst, then heating to 40-100 ℃ under the protection of inert gas, stirring for 10-60 minutes, then adding the halogenated compound represented by the general formula (iii), reacting for 4-12 hours, then filtering the reaction solution, distilling the filtrate under reduced pressure to remove the solvent, washing with water for three times, extracting with chloroform, collecting the organic phase, and evaporating to dryness to obtain the first intermediate product which is liquid and colorless or light yellow.

In a preferred embodiment, in step two, the free radical addition reaction is carried out by dissolving the first intermediate product in an organic solvent, adding a free radical initiator, raising the temperature to 40-100 ℃ under the protection of inert gas, slowly adding thioacetic acid, carrying out the free radical addition reaction for 4-12 hours, and then distilling under reduced pressure to remove the solvent to obtain a liquid colorless or light yellow second intermediate product.

In a preferred embodiment, in step three, the hydrolysis reaction is performed by dissolving the second intermediate product in an organic solvent, adding hydrochloric acid or sodium hydroxide, heating to 50-100 ℃ for reaction for 3-12 hours, distilling under reduced pressure to remove the solvent, washing twice with 2-8% sodium bicarbonate solution, extracting with chloroform, collecting the organic phase, and evaporating to dryness to obtain a colorless or light yellow viscous liquid product, i.e., the polythiol compound.

In a preferred embodiment, the epoxy resin is an aromatic epoxy resin and/or an aliphatic epoxy resin.

In a preferred embodiment, the epoxy resin is a combination of bisphenol A type epoxy resin and bisphenol A epoxy monoacrylate in a weight ratio of 1 (0.3-0.9).

In a preferred embodiment, the ratio of the equivalents of thiol functional groups of the polythiol compound to the equivalents of epoxy functional groups of the epoxy resin is from 0.5 to 2.0, preferably from 0.8 to 1.2.

In a preferred embodiment, the acrylate compound is selected from at least one of epoxy (meth) acrylate, urethane (meth) acrylate, polyester (meth) acrylate, polyether (meth) acrylate, silane-modified (meth) acrylate, polyol (meth) acrylate, polyolefin (meth) acrylate, melamine (meth) acrylate, and (meth) acrylated acrylic resin.

In a preferred embodiment, the acrylate compound is a combination of epoxy acrylate and tricyclodecane dimethanol diacrylate in a weight ratio of 1 (0.5-1.5).

In a preferred embodiment, the curing accelerator is selected from at least one of an imidazole-based curing accelerator, a tertiary amine-based curing accelerator, and a phosphorus compound-based curing accelerator.

In a preferred embodiment, the photoinitiator is a free radical photoinitiator; the free radical photoinitiator is a cracking type photoinitiator and/or a hydrogen abstraction type photoinitiator.

In a preferred embodiment, the polymerization inhibitor is at least one selected from the group consisting of hydroquinone, p-hydroxyanisole, p-benzoquinone, methylhydroquinone, 2-tert-butylhydroquinone, 2, 5-di-tert-butylhydroquinone, 4-hydroxypiperidinol oxyl, phenothiazine and anthraquinone.

In a preferred embodiment, the stabilizer is selected from at least one of a liquid borate compound, an aluminum chelating agent, and barbituric acid.

In a preferred embodiment, the photo/thermal dual curable resin composition further includes a coupling agent and/or an auxiliary agent; the coupling agent is at least one selected from gamma- (2, 3-epoxypropoxy) propyltrimethoxysilane, beta- (3, 4-epoxycyclohexyl) ethyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 8-epoxypropoxytrimethoxysilane, gamma-mercaptopropyltrimethoxysilane, vinyltrimethoxysilane and vinyltriethoxysilane; the auxiliary agent is selected from at least one of filler, antioxidant, flame retardant, adhesion promoter, diluent, pigment, defoaming agent, leveling agent and ion trapping agent; the content of the coupling agent is 0.01-5 parts by weight; the content of the auxiliary agent is 0.01-30 parts by weight.

The invention also provides a preparation method of the light/heat dual-curing resin composition, wherein the method comprises the step of uniformly mixing the epoxy resin, the polythiol compound, the acrylate compound, the curing accelerator, the photoinitiator, the polymerization inhibitor, the stabilizer and the optional coupling agent and/or the auxiliary agent under the condition of keeping out of the sun to obtain the dual-curing reaction type polyurethane hot melt adhesive.

In a preferred embodiment, the uniformly mixing mode comprises stirring the acrylate compound, the photoinitiator and the polymerization inhibitor for 20-40 minutes at the temperature of 20-30 ℃, the vacuum degree of-0.05 MPa to-0.1 MPa and the rotation speed of 40-60 r/min under the condition of keeping out of the sun, adding the epoxy resin, the polythiol compound and the stabilizer for stirring again for 20-40 minutes at the temperature of 20-30 ℃, the vacuum degree of-0.05 MPa to-0.1 MPa and the rotation speed of 40-60 r/min, then adding the curing accelerator and the optional silane coupling agent and the auxiliary agent for stirring for 20-40 minutes at the temperature of 20-30 ℃, the vacuum degree of-0.05 MPa to-0.1 MPa and the rotation speed of 40-60 r/min, and sealing and packaging under the condition of keeping out of the sun.

In addition, the present invention also provides the use of the photo/thermal dual curable resin composition as an adhesive or sealant for the bonding or sealing of electronic parts.

The invention also provides application of the light/heat dual-curing resin composition as an adhesive or a sealant for bonding or sealing a sensor or a camera.

The invention has the following beneficial effects:

(1) the invention adopts the polythiol compound with a specific structure, the epoxy resin thermosetting system and the acrylate photocuring system to form the light/heat dual-curing resin composition, makes up the defects of two single curing modes of traditional thermosetting and photocuring, and has the characteristics of quick positioning, low-temperature curing, high bonding strength, good heat resistance and humidity resistance and the like;

(2) the polythiol compound provided by the invention has low odor, so that the problem of overlarge odor of the corresponding resin composition can be avoided;

(3) the polythiol compound provided by the invention is viscous liquid at normal temperature, is easy to be uniformly mixed with resin, does not generate crystal precipitation, has long application life, can be directly used as a curing agent for curing a resin composition, does not need to be additionally coupled to form an oligomer mixture, does not need to be combined with other polythiol compounds, has low cost, and can be used as a component of an adhesive and a sealant.

Drawings

FIG. 1 is a drawing showing 5,5 '-bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopropoxy) biphenyl¹H-NMR chart;

FIG. 2 is an IR spectrum of 5,5 '-bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopropoxy) biphenyl;

FIG. 3 is a drawing showing 5,5' -bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopropoxy) -3,3' -dimethoxybiphenyl¹H-NMR chart;

FIG. 4 is an IR spectrum of 5,5' -bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopropoxy) -3,3' -dimethoxybiphenyl.

Detailed Description

The light/heat dual-curing resin composition provided by the invention contains epoxy resin, polythiol compound, acrylate compound, curing accelerator, photoinitiator, polymerization inhibitor and stabilizer, and on the basis, the light/heat dual-curing resin composition can also contain coupling agent and/or auxiliary agent. Wherein, the content of the epoxy resin is 20-40 parts by weight, such as 20, 22, 25, 28, 30, 32, 35, 38 and 40 parts by weight. The polythiol compound is contained in an amount of 10 to 35 parts by weight, such as 10, 12, 15, 18, 20, 22, 25, 28, 30, 32, 35 parts by weight. The content of the acrylate compound is 20-40 parts by weight, such as 20, 22, 25, 28, 30, 32, 35, 38, 40 parts by weight. The content of the curing accelerator is 1-5 parts by weight, such as 1, 2,3, 4 and 5 parts by weight. The content of the photoinitiator is 0.3-5 parts by weight, such as 0.3, 0.5, 1, 1.5, 2, 2.5 and 3 parts by weight. The polymerization inhibitor is 0.01-3 weight parts, such as 0.01, 0.1, 0.5, 1, 1.5, 2, 2.5, 3 weight parts. The content of the stabilizer is 0.1-3 parts by weight, such as 0.1, 0.5, 1, 1.5, 2, 2.5 and 3 parts by weight. The coupling agent is preferably present in an amount of 0.01 to 5 parts by weight, such as 0.01, 0.1, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5 parts by weight. The content of the auxiliaries is preferably from 0.01 to 30 parts by weight, such as 0.01, 1, 5, 10, 15, 20, 25, 30 parts by weight.

The polythiol compound has a structure represented by general formula (I):

in the general formula (I), R¹、R²、R³And R⁴Wherein only one is a mercaptoalkoxy group having 2 to 5 carbon atoms, R⁵、R⁶、R⁷And R⁸Wherein only one is a mercaptoalkoxy group having 2 to 5 carbon atoms, R¹、R²、R³、R⁴、R⁵、 R⁶、R⁷And R⁸The remaining six of (A) are each independently selected from one of a hydrogen atom, an alkyl group having 1 to 3 carbon atoms and a lower alkoxy group having 1 to 3 carbon atoms. The mercaptoalkoxy group having 2 to 5 carbon atoms may be, for example, mercaptoethoxy, mercapto-n-propoxy, mercapto-isopropoxy, mercapto-n-butoxy, mercapto-sec-butoxy, mercapto-isobutoxy, mercapto-tert-butoxy, mercapto-n-pentoxy, mercapto-isopentoxy, mercapto-tert-pentoxy or mercapto-neopentoxy. Specific examples of the alkyl group having 1 to 3 carbon atoms include, but are not limited to: methyl, ethyl, n-propyl or isopropyl. Specific examples of the alkoxy group having 1 to 3 carbon atoms include, but are not limited to: methoxy, ethoxy, propoxy or isopropoxy.

In the polythiol compound represented by the general formula (I), preferably, R¹、R²And R⁴One of them is a mercaptoalkoxy group having 2 to 5 carbon atoms and the other two are both hydrogen atoms, R³And R⁷Are respectively independentIs selected from hydrogen atom or methoxy, R⁵、 R⁶And R⁸One of them is a mercaptoalkoxy group having 2 to 5 carbon atoms and the other two are both hydrogen atoms. More preferably, in the polythiol compound represented by the general formula (I), R is¹And R⁵Are each a hydrogen atom, R³And R⁷Each independently selected from a hydrogen atom or a methoxy group, R²And R⁴One of them is a mercaptoalkoxy group having 2 to 5 carbon atoms and the other is a hydrogen atom, R⁶And R⁸One of them is a mercaptoalkoxy group having 2 to 5 carbon atoms and the other is a hydrogen atom. Most preferably, in the polythiol compound represented by the general formula (I), R is¹And R⁵Are each a hydrogen atom, R³And R⁷Each independently selected from a hydrogen atom or a methoxy group, and when R is²And R⁶When all are mercapto alkoxy groups having 2 to 5 carbon atoms, R⁴And R⁸Are each a hydrogen atom; when R is⁴And R⁸When all are mercapto alkoxy groups having 2 to 5 carbon atoms, R²And R⁶Are each a hydrogen atom; when R is⁴And R⁶When all are mercapto alkoxy groups having 2 to 5 carbon atoms, R²And R⁸Are each a hydrogen atom; when R is²And R⁸When all are mercapto alkoxy groups having 2 to 5 carbon atoms, R⁴And R⁶Are all hydrogen atoms.

Specific examples of the polythiol compound include, but are not limited to: 5,5 '-bis (3-mercaptopropyl) -2,2' -bis (3-mercaptobutoxy) biphenyl (R)¹、R²、R³、R⁵、R⁶And R⁷Are each a hydrogen atom, R⁴And R⁸All of which are C4 mercaptoalkoxy), 5' -bis (3-mercaptopropyl) -2,2' -bis (3-mercaptobutoxy) -3,3' -dimethoxybiphenyl (R)¹、R²、R⁵And R⁶Are each a hydrogen atom, R³And R⁷Are all methoxy radicals, R⁴And R⁸All of which are C4 mercaptoalkoxy), 5 '-bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopentyloxy) biphenyl (R)¹、R²、R³、R⁵、R⁶And R⁷Are all hydrogenAtom, R⁴And R⁸All of which are C5 mercaptoalkoxy), 5' -bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopentyloxy) -3,3' -dimethoxybiphenyl (R)¹、 R²、R⁵And R⁶Are each a hydrogen atom, R³And R⁷Are all methoxy radicals, R⁴And R⁸Mercaptoalkoxy group having 5 carbon atoms, 5 '-bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopropoxy) biphenyl (R)¹、R²、R³、R⁵、R⁶And R⁷Are each a hydrogen atom, R⁴And R⁸Mercaptoalkoxy group having 3 carbon atoms) and 5,5' -bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopropoxy) -3,3' -dimethoxybiphenyl (R)¹、R²、R⁵And R⁶Are each a hydrogen atom, R³And R⁷Are all methoxy radicals, R⁴And R⁸All being mercaptoalkoxy groups having 3 carbon atoms).

In one embodiment, the polythiol compound is prepared by a process comprising the steps of:

in the general formula (II), R⁹、R¹⁰、R¹¹And R¹²Has one and only oneEach is hydroxy, R¹³、R¹⁴、R¹⁵And R¹⁶In which only one is hydroxy, R⁹、R¹⁰、R¹¹、R¹²、R¹³、R¹⁴、R¹⁵And R¹⁶The remaining six of them are each independently selected from one of a hydrogen atom, an alkyl group having 1 to 3 carbon atoms and an alkoxy group having 1 to 3 carbon atoms. Preferably, R⁹、 R¹⁰And R¹²One of them being a hydroxyl group and the other two being hydrogen atoms, R¹¹And R¹⁵Each independently selected from a hydrogen atom or a methoxy group, R¹³、R¹⁴And R¹⁶One of which is a hydroxyl group and the other two are both hydrogen atoms. More preferably, R⁹And R¹³Are each a hydrogen atom, R¹¹And R¹⁵Each independently selected from a hydrogen atom or a methoxy group, R¹⁰And R¹²One of which is a hydroxyl group and the other is a hydrogen atom, R¹⁴And R¹⁶One of which is a hydroxyl group and the other is a hydrogen atom. Most preferably, R⁹And R¹³Are each a hydrogen atom, R¹¹And R¹⁵Each independently selected from a hydrogen atom or a methoxy group, and when R is¹⁰And R¹⁴When both are hydroxy, R¹²And R¹⁶Are each a hydrogen atom; when R is¹²And R¹⁶When both are hydroxy, R¹⁰And R¹⁴Are each a hydrogen atom; when R is¹²And R¹⁴When both are hydroxy, R¹⁰And R¹⁶Are each a hydrogen atom; when R is¹⁰And R¹⁶When both are hydroxy, R¹²And R¹⁴Are all hydrogen atoms.

In the first step, the substitution reaction is preferably performed by dissolving the biphenol compound represented by the general formula (ii) in an organic solvent, adding an alkali to provide an alkaline condition, adding a phase transfer catalyst, then heating to 40-100 ℃ under the protection of an inert gas, stirring for 10-60 minutes, then adding the halogenated compound represented by the general formula (iii), reacting for 4-12 hours, then filtering the reaction solution, distilling the filtrate under reduced pressure to remove the solvent, washing with water for three times, extracting with chloroform, collecting the organic phase, and evaporating to dryness to obtain a liquid colorless or light yellow first intermediate product.

The kind of the base is not particularly limited and may be conventionally selected in the art, and specific examples thereof include, but are not limited to: at least one of potassium carbonate, sodium hydroxide, potassium hydroxide, triethylamine and p-dimethylaminopyridine.

The phase transfer catalyst may be any of various conventional materials capable of catalyzing a substitution reaction of a phenolic hydroxyl group in the biphenol compound represented by the general formula (ii) with chlorine or bromine in the halogenated compound represented by the general formula (iii), and is preferably at least one of cyclic crown ethers, polyethers, and ammonium compounds. Specific examples of the cyclic crown ethers include, but are not limited to: at least one of 18-crown-6, 15-crown-5 and cyclodextrin. Specific examples of such polyethers include, but are not limited to: chain polyethylene glycol and/or chain polyethylene glycol dialkyl ether. Specific examples of such ammonium species include, but are not limited to: at least one of benzyltriethylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium chloride, tetrabutylammonium hydrogen sulfate, trioctylmethylammonium chloride, dodecyltrimethylammonium chloride and tetradecyltrimethylammonium chloride.

And in the second step, the free radical addition reaction mode is that the first intermediate product is dissolved in an organic solvent, a free radical initiator is added, the temperature is raised to 40-100 ℃ under the protection of inert gas, thioacetic acid is slowly added to carry out the free radical addition reaction for 4-12 hours, and then the solvent is removed by reduced pressure distillation to obtain a liquid colorless or light yellow second intermediate product.

The free radical initiator may be any one of the existing substances capable of initiating the free radical addition reaction between the double bond in the first intermediate product and the mercapto group in the thioacetic acid, and may be an azo initiator and/or a peroxy initiator. Specific examples of the azo-based initiator include, but are not limited to: at least one of azobisisobutyronitrile, 2 '-azobis (2-methylbutyronitrile), dimethyl 2,2' -azobis (2-methylpropionate), dimethyl azobisisobutyrate, azobisisobutyramidine hydrochloride, azobisformamide, azobisisopropylimidazoline hydrochloride, azobisisobutyronitrile formamide, azobiscyclohexylcarbonitrile, azobiscyanovaleric acid, azobisisopropylimidazoline, azobisisovaleronitrile, and azobisisoheptonitrile. Specific examples of the peroxy-based initiator include, but are not limited to: at least one of t-hexyl peroxyisopropyl monocarbonate, t-hexyl peroxy-2-ethylhexanoate, 1,3, 3-tetramethylbutyl peroxy-2-ethylhexanoate, t-butyl peroxy pivalate, t-hexyl peroxy pivalate, t-butyl peroxy neodecanoate, t-hexyl peroxy neodecanoate, 1,3, 3-tetramethylbutyl peroxy neodecanoate, 1-bis (t-hexyl peroxy) cyclohexane, benzoyl peroxide, 3,5, 5-trimethyl peroxy hexanoyl, lauroyl peroxide, and t-butyl benzoyl peroxide. From the viewpoint of availability of raw materials, the radical initiator is preferably azobisisobutyronitrile, 2 '-azobis (2-methylbutyronitrile), dimethyl 2,2' -azobis (2-methylpropionate), t-hexylperoxyisopropyl monocarbonate, t-hexylperoxy2-ethylhexanoate, 1,3, 3-tetramethylbutylperoxy 2-ethylhexanoate, t-butylperoxy pivalate, at least one of tert-hexyl peroxypivalate, tert-butyl peroxyneodecanoate, tert-hexyl peroxyneodecanoate, 1,3, 3-tetramethylbutyl peroxyneodecanoate, 1-bis (tert-hexyl peroxy) cyclohexane, benzoyl peroxide, 3,5, 5-trimethylhexanoyl peroxide, and lauroyl peroxide.

In the third step, the hydrolysis reaction is preferably performed by dissolving the second intermediate product in an organic solvent, adding hydrochloric acid or sodium hydroxide, heating to 50-100 ℃ for reaction for 3-12 hours, distilling under reduced pressure to remove the solvent, washing twice with 2-8% sodium bicarbonate solution, extracting with chloroform, collecting the organic phase, and evaporating to dryness to obtain a colorless or light yellow viscous liquid product, i.e., the polythiol compound.

In a preferred embodiment of the present invention, the substitution reaction of the first step is carried out in the presence of an organic solvent I, the radical addition reaction of the second step is carried out in the presence of an organic solvent II, and the hydrolysis reaction of the third step is carried out in the presence of an organic solvent III. The organic solvent I and the organic solvent II are preferably at least one selected from methanol, ethanol, propanol, butanol, isopropanol, ethyl acetate, propyl acetate, butyl acetate, tetrahydrofuran, dioxane, acetonitrile, toluene, xylene, dichloromethane, chloroform, carbon tetrachloride, dimethylformamide, dimethylacetamide and dimethylsulfoxide. The organic solvent III is preferably an alcohol, more preferably a C1-5 monoalcohol, such as at least one of methanol, ethanol, propanol and n-butanol.

The epoxy resin may be an aromatic epoxy resin and/or an aliphatic epoxy resin, and specific examples thereof include, but are not limited to: aliphatic polyglycidyl ether compounds, aromatic polyglycidyl ether compounds, aliphatic polyglycidyl ester compounds, aromatic polyglycidyl ester compounds, alicyclic polyglycidyl ether ester compounds, aliphatic polyglycidyl amine compounds, hydantoin type polyglycidyl compounds, novolak type polyglycidyl ether compounds, epoxidized diene polymers, 3, 4-epoxy-6-methylcyclohexylmethyl-3, 4-epoxy-6-methylcyclohexanedioxane carboxylates, rubber-modified epoxy resins (modified by CTBN, ATBN, or the like), polyalkylene glycol type epoxy resins, ether elastomer-added bisphenol A type epoxy resins, silicone rubber-modified epoxy resins, and acrylic modified epoxy resins. The epoxy resin is preferably a combination of bisphenol A type epoxy resin and bisphenol A epoxy monoacrylate in a weight ratio of 1 (0.3-0.9), such as 1:0.3, 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, which is more advantageous for improving the heat resistance, adhesion, moisture barrier property and resistance to wet heat hydrolysis of the light/heat dual curable resin composition.

The ratio of the thiol functional group equivalents of the polythiol compound to the epoxy functional group equivalents of the epoxy resin is preferably 0.5 to 2.0, such as 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0. The ratio of the thiol functional group equivalent of the polythiol compound to the epoxy functional group equivalent of the epoxy resin is most preferably 0.8 to 1.2, and when the ratio is outside this range, the glass transition temperature, the adhesive property, and the moisture barrier property of the resulting light/heat dual curable resin composition are lowered to some extent.

The present invention is not particularly limited with respect to the specific kind of the acrylate compound, and specific examples thereof include, but are not limited to: at least one of epoxy (meth) acrylate, urethane (meth) acrylate, polyester (meth) acrylate, polyether (meth) acrylate, silane-modified (meth) acrylate, polyol (meth) acrylate, polyolefin (meth) acrylate, melamine (meth) acrylate, and (meth) acrylated acrylic resin. The acrylate compound is preferably a combination of epoxy acrylate and tricyclodecane dimethanol diacrylate in a weight ratio of 1 (0.5-1.5), which is more advantageous in improving heat resistance, adhesion, moisture barrier properties and resistance to wet heat hydrolysis of the light/heat dual curable resin composition.

The present invention is not particularly limited in kind of the curing accelerator, and specific examples thereof include, but are not limited to: at least one of an imidazole-based curing accelerator, a tertiary amine-based curing accelerator, and a phosphorus compound-based curing accelerator. The curing accelerator is preferably a latent curing accelerator. The latent curing accelerator is a compound which is inactive at room temperature and is activated by heating to function as a curing accelerator, and examples thereof include: imidazole compounds which are solid at normal temperature, organic acid dihydrazides; solid dispersion type amine adduct-based latent curing accelerators such as reaction products (amine-epoxy adduct-based) of amine compounds and epoxy compounds; a reaction product of an amine compound with an isocyanate compound or a urea compound (urea-type adduct system), and the like.

The photoinitiator of the present invention is not particularly limited in kind, and may be various existing radical photoinitiators capable of initiating polymerization of carbon-carbon double bonds in unsaturated resins to complete curing, specifically, cleavage type photoinitiators and/or hydrogen abstraction type photoinitiators. Specific examples of the radical type photoinitiator include, but are not limited to: 2-hydroxy-2-methyl-1-phenyl-1-propanone, 1-hydroxycyclohexylphenylketone, 2-hydroxy-4- (2-hydroxyethoxy) -2-methylpropiophenone, 2,4, 6-trimethylbenzoyl-diphenylphosphine oxide, ethyl 2,4, 6-trimethylbenzoylphenylphosphonate, bis (2,4, 6-trimethylbenzoyl) phenylphosphine oxide, 2-methyl-1- [4- (methylthio) phenyl ] -2- (4-morpholinyl) -1-propanone, 2-phenylbenzyl-2-dimethylamine-1- (4-morpholinylbenzyl) butanone, 4-benzoyl-4' -methyl-diphenylsulfide, methyl-2-phenylpropiophenone, methyl-2-propanone, methyl-2-methylbenzyl-1-propanone, methyl-4-methylbenzyl-ether, methyl-1-propanone, methyl-2-methylbenzyl-4-methylbenzyl-1-methyl-phenyl-2-methyl-1-propanone, methyl-2-methylbenzyl-methyl-1-methyl-2-methyl-phenyl-1-propanone, methyl-2-methylbenzyl-methyl-1-phenyl-methyl-1-one, methyl-phenyl-2-methyl-one, methyl-phenyl-2-methyl-one, methyl-2-phenyl-one, methyl-2-methyl-one, and methyl-one, 2- (4-methylbenzyl) -2- (dimethylamino) -1- (4-morpholinophenyl) -1-butanone, 1' - (methylenebis-4, 1-phenylene) bis [ 2-hydroxy-2-methyl-1-propanone ], 2-dimethoxy-2-phenylacetophenone, 2-diethoxy-1-phenylhexanone, bis 2, 6-difluoro-3-pyrrolophenyldicyclopentadienyl titanium, methyl benzoylformate, benzophenone, 4-methylbenzophenone, 4-phenylbenzophenone, 4-chlorobenzophenone, methyl benzoylbenzoate, ethyl 4-dimethylaminobenzoate, isooctyl p-dimethylaminobenzoate, methyl tert-butyl acetate, methyl ethyl p-dimethylaminobenzoate, methyl benzoate, ethyl p-dimethylaminobenzoate, ethyl p-ethyl ester, ethyl p-methyl benzoate, ethyl p-dimethylaminobenzoate, ethyl ester, p-dimethylaminobenzoate, p-ethyl ester, p-methyl benzoate, p-ethyl ester, p-methyl benzoate, p-ethyl ester, p-methyl benzoate, p-ethyl ester, p-methyl benzoate, p-ethyl ester, p-methyl ester, p-ethyl ester, p-methyl ester, p-ethyl ester, p-ethyl ester, p-p, 4,4' -bis (diethylamino) benzophenone, isopropylthioxanthone, 2, 4-diethylthioxanthone, and 2-ethylanthraquinone.

The type of the polymerization inhibitor in the present invention is not particularly limited, and may be conventionally selected in the art, and specific examples thereof include, but are not limited to: at least one of hydroquinone, p-hydroxyanisole, p-benzoquinone, methylhydroquinone, 2-tert-butylhydroquinone, 2, 5-di-tert-butylhydroquinone, 4-hydroxypiperidinol oxyl, phenothiazine and anthraquinone.

The purpose of adding the stabilizer into the photo/thermal dual-curable resin composition is to improve the storage stability and prolong the storage life. The stabilizer may be any of various conventional stabilizers mainly composed of an epoxy resin and an acrylate compound, and is preferably at least one selected from the group consisting of a liquid borate compound, an aluminum chelate compound and barbituric acid in view of improving a storage stability effect. Specific examples of the liquid borate compounds include, but are not limited to: 2,2 '-oxybis (5,5' -dimethyl-1, 3, 2-oxahexaborane), trimethyl borate, triethyl borate, tri-n-propyl borate, triisopropyl borate, tri-n-butyl borate, pentyl borate, triallyl borate, trihexyl borate, tricyclohexyl borate, trioctyl borate, trinonyl borate, tridecyl borate, trihexadecyl borate, trioctadecyl borate, triphenyl borate, tricresyl borate, triethanolamine borate, and the like. The liquid boric acid ester compound is preferable because it is liquid at room temperature (25 ℃) and the viscosity of the complex is suppressed to be low. The aluminum chelate compound may be, for example, aluminum chelate compound A (available from Chuangmo Seiki chemical Co., Ltd.).

The photo/thermal dual curable resin composition preferably further includes a coupling agent to improve the dispersion property of the inorganic substance in the system in the resin matrix. Specific examples of the coupling agent include, but are not limited to: at least one of gamma- (2, 3-epoxypropoxy) propyltrimethoxysilane, beta- (3, 4-epoxycyclohexyl) ethyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 8-epoxypropoxytyltrimethoxysilane, gamma-mercaptopropyltrimethoxysilane, vinyltrimethoxysilane, and vinyltriethoxysilane.

The photo/thermal dual curable resin composition preferably further includes an auxiliary agent. The auxiliary agent may be at least one selected from fillers, antioxidants, flame retardants, adhesion promoters, diluents, pigments, defoamers, leveling agents, and ion traps, and specific selection of the above various auxiliary agents is well known to those skilled in the art and will not be described herein.

The preparation method of the light/heat dual-curing resin composition comprises the step of uniformly mixing epoxy resin, polythiol compound, acrylate compound, curing accelerator, photoinitiator, polymerization inhibitor, stabilizer and optional coupling agent and/or auxiliary agent under the condition of avoiding light to obtain the light/heat dual-curing resin composition.

The invention has no special limitation on the mode of uniformly mixing the components under the condition of keeping out of the sun, as long as the components can be uniformly mixed and the whole mixing process is not influenced by the light. In a preferred embodiment, the uniformly mixing mode comprises stirring the acrylate compound, the photoinitiator and the polymerization inhibitor for 20-40 minutes at the temperature of 20-30 ℃, the vacuum degree of-0.05 MPa to-0.1 MPa and the rotation speed of 40-60 r/min under the condition of keeping out of the sun, adding the epoxy resin, the polythiol compound and the stabilizer for stirring again for 20-40 minutes at the temperature of 20-30 ℃, the vacuum degree of-0.05 MPa to-0.1 MPa and the rotation speed of 40-60 r/min, then adding the curing accelerator and the optional silane coupling agent and the auxiliary agent for stirring for 20-40 minutes at the temperature of 20-30 ℃, the vacuum degree of-0.05 MPa to-0.1 MPa and the rotation speed of 40-60 r/min, and sealing and packaging under the condition of keeping out of the sun. The types and the amounts of the components are described above, and are not described herein.

The present invention also provides the use of the photo/thermal dual curable resin composition as an adhesive or sealant for the bonding or sealing of electronic parts.

The present invention will be further described with reference to the following examples.

In the following preparation examples, the starting material sources used in the preparation of the polythiol compounds 5,5' -bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopropoxy) biphenyl and 5,5' -bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopropoxy) -3,3' -dimethoxybiphenyl were as follows: 5,5' -diallyl-2, 2' -biphenol available from Sahn's chemical technology (Shanghai) Inc. under the designation E100338; the phase transfer catalyst 18-crown-6 is from Shanghai Tantake Technology, Inc. under the designation 30243D; allyl bromide is available from Shanghai Tantake Technique, Inc. under the designation 13125C; azobisisobutyronitrile (abbreviated as "AIBN") available from shanghai mclin biochemistry technology limited under the designation a 800353; the thioacetic acid is from national pharmaceutical group chemical reagent limited, and the brand is 80128126; 5,5 '-diallyl-3, 3' -dimethoxy-2, 2 '-biphenol available from Sahn's chemical technology (Shanghai) Inc. under the designation D050881.

Preparation example 1

This preparation example is used to illustrate the preparation of a polythiol compound (5,5 '-bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopropoxy) biphenyl) by the following specific steps and reaction schemes:

the method comprises the following steps: dissolving 80g of 5,5 '-diallyl-2, 2' -biphenol in 200mL of acetone, adding 103.6g of potassium carbonate and 18-crown-67.9 g of a phase transfer catalyst, heating to 70 ℃ under the protection of inert gas, stirring for 10 minutes, slowly adding 79.8g of allyl bromide, reacting for 8 hours, filtering the reaction solution, distilling the filtrate under reduced pressure to remove the solvent, washing with water for three times, extracting with trichloromethane, collecting the organic phase, and evaporating to dryness to obtain a liquid light yellow first intermediate product;

step two: dissolving the first intermediate product obtained in the second step in 200mL of tetrahydrofuran, adding 5.4g of azodiisobutyronitrile serving as a free radical initiator, heating to 70 ℃ under the protection of inert gas, slowly adding 96.2g of thioacetic acid, reacting for 12 hours, and then carrying out reduced pressure distillation to remove the solvent and excessive thioacetic acid to obtain a liquid light yellow second intermediate product;

step three: and (3) dissolving the second intermediate product obtained in the second step in 300mL of methanol, adding 60mL of hydrochloric acid for hydrolysis, heating to 60 ℃ for hydrolysis reaction for 12 hours, distilling under reduced pressure to remove the solvent, washing twice with a 5% sodium bicarbonate solution, extracting with chloroform, collecting the organic phase, and evaporating to dryness to obtain 124.8g of a final product which is a light yellow viscous liquid, namely 5,5 '-bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopropoxy) biphenyl, wherein the total yield is 86.2%, the mercaptan equivalent weight is 120g/eq, and the molecular weight is 482.8. The 5,5 '-bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopropoxy) biphenyl was substantially free of sulfur odor.

Preparation of the 5,5 '-bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopropoxy) biphenyl¹The H-NMR chart and the IR spectrum are shown in FIGS. 1 and 2, respectively. As can be seen from FIGS. 1 and 2, the 5,5 '-bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopropoxy) biphenyl has the formula (IV).

Preparation example 2

This preparation example is used to illustrate the preparation of a polythiol compound (5,5' -bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopropoxy) -3,3' -dimethoxybiphenyl) by the following specific steps and reaction scheme:

the method comprises the following steps: dissolving 98g of 5,5' -diallyl-3, 3' -dimethoxy-2, 2' -biphenol in 250mL of acetone, adding 103.6g of potassium carbonate and 18-crown-67.9 g of a phase transfer catalyst, heating to 70 ℃ under the protection of inert gas, stirring for 10 minutes, slowly adding 79.8g of allyl bromide, reacting for 8 hours, filtering the reaction solution, distilling the filtrate under reduced pressure to remove the solvent, washing with water for three times, extracting with trichloromethane, collecting the organic phase, and evaporating to dryness to obtain a liquid pale yellow first intermediate product;

step two: dissolving the first intermediate product obtained in the step one in 200mL of tetrahydrofuran, adding 5.4g of azodiisobutyronitrile serving as a free radical initiator, heating to 70 ℃ under the protection of inert gas, slowly adding 96.2g of thioacetic acid, reacting for 12 hours, and then carrying out reduced pressure distillation to remove the solvent and excessive thioacetic acid to obtain a liquid light yellow second intermediate product;

step three: and (3) dissolving the second intermediate product obtained in the second step in 300mL of methanol, adding 60mL of hydrochloric acid for hydrolysis, heating to 70 ℃ for hydrolysis reaction for 12 hours, distilling under reduced pressure to remove the solvent, washing twice with a 5% sodium bicarbonate solution, extracting with chloroform, collecting the organic phase, and evaporating to dryness to obtain 137.7g of a final product which is a light yellow viscous liquid, namely 5,5' -bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopropoxy) -3,3' -dimethoxybiphenyl, wherein the total yield is 84.5%, the mercaptan equivalent is 135g/eq, and the molecular weight is 542.8. The 5,5' -bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopropoxy) -3,3' -dimethoxybiphenyl had substantially no sulfur odor.

Preparation of 5,5' -bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopropoxy) -3,3' -dimethoxybiphenyl¹The H-NMR chart and the IR spectrum are shown in FIGS. 3 and 4, respectively. As can be seen from fig. 3 and 4, the 5,5' -bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopropoxy) -3,3' -dimethoxybiphenyl has the structure shown in formula (v).

Examples 1 to 17

Accurately weighing the raw materials according to the weight parts in the table 1, stirring the acrylate compound, the photoinitiator and the polymerization inhibitor for 30 minutes at the temperature of 25 ℃, the vacuum degree of-0.07 MPa and the rotating speed of 50 revolutions per minute in a dark place, then adding the epoxy resin, the polythiol compound and the stabilizer for stirring for 30 minutes at the temperature of 25 ℃, the vacuum degree of-0.07 MPa and the rotating speed of 50 revolutions per minute, then adding the curing agent, the silane coupling agent and the auxiliary agent for stirring for 30 minutes at the temperature of 25 ℃, the vacuum degree of-0.07 MPa and the rotating speed of 50 revolutions per minute, and sealing and packaging in a dark place to obtain the light/heat dual-curing resin composition.

Comparative examples 1 to 5

Accurately weighing the raw materials according to the weight parts in the table 2, stirring the acrylate compound, the photoinitiator and the polymerization inhibitor for 30 minutes at the temperature of 25 ℃, the vacuum degree of-0.07 MPa and the rotating speed of 50 revolutions per minute in a dark place, then adding the epoxy resin, the polythiol compound and the stabilizer for stirring for 30 minutes at the temperature of 25 ℃, the vacuum degree of-0.07 MPa and the rotating speed of 50 revolutions per minute, then adding the curing agent, the silane coupling agent and the auxiliary agent for stirring for 30 minutes at the temperature of 25 ℃, the vacuum degree of-0.07 MPa and the rotating speed of 50 revolutions per minute, and sealing and packaging in a dark place to obtain the light/heat dual-curing resin composition.

TABLE 1

TABLE 2

In tables 1 and 2, a1 was 5,5' -bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopropoxy) biphenyl (thiol equivalent: 120g/eq), a2 was 5,5' -bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopropoxy) -3,3' -dimethoxybiphenyl (thiol equivalent: 135g/eq), A3 was PEMP (thiol equivalent: 122g/eq), a4 was the bifunctional hybrid thiol compound disclosed in CN112840004A (thiol equivalent: 211g/eq), a5 was 1,3,4, 6-tetrakis (2-mercaptoethyl) glycoluril (thiol equivalent: 95g/eq), a6 was 1,1- (dithiobisethanediyl) -bis [3,4, 6-tris (2-mercaptoethyl) glycoluril ] (thiol equivalent: 127 g/eq); b1 is bisphenol A epoxy resin EPICLON EXA-850CRP (epoxy equivalent: 170-175g/eq), B2 is bisphenol A epoxy monoacrylate EA-1010LC (epoxy equivalent: 412.5 g/eq); c1 is epoxy acrylate CN121, C2 is tricyclodecane dimethanol diacrylate SR 833S; d is a latent curing accelerator NOVACURE HXA9322 HP; e1 is 2-hydroxy-2-methyl-1-phenylpropanone Irgacure 1173, E2 is diphenyl- (2,4, 6-trimethylbenzoyl) oxyphosphorus Omnirad TPO; f is p-hydroxyanisole MEHQ; g is triisopropyl borate W330012; h is a silane coupling agent KBM 503; i is fumed silica AEROSIL R202.

The main raw material sources used in examples 1-17 and comparative examples 1-5 are as follows:

the polythiol compound 5,5 '-bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopropoxy) biphenyl was prepared from preparation example 1, had a thiol equivalent of 120g/eq, a molecular weight of 482.8, and a structural formula shown in formula (IV):

the polythiol compound 5,5' -bis (3-mercaptopropyl) -2,2' -bis (3-mercaptopropoxy) -3,3' -dimethoxybiphenyl was prepared by preparation example 2, had a thiol equivalent of 135g/eq, a molecular weight of 542.8, and a structural formula shown in formula (V):

pentaerythritol tetrakis (3-mercaptopropionate) is PEMP from SC organic Chemicals, Japan, has a mercaptan equivalent of 122g/eq, a molecular weight of 488.6, and a structural formula represented by the formula (VI):

the bifunctional hybrid thiol compound has a structure represented by formula (VII), is liquid at room temperature, has a molecular weight of 389, and has a thiol equivalent of 211 g/eq:

1,3,4, 6-tetrakis (2-mercaptoethyl) glycoluril, derived from the four kingdom chemical industries, as a crystalline solid at room temperature, with a thiol equivalent of 95 g/eq;

the mercaptan equivalent weight of 1,1- (dithio-bis-ethanediyl) -bis [3,4, 6-tris (2-mercaptoethyl) glycoluril ] is 127g/eq, and the preparation method comprises the following steps: adding 3.18g of 1,3,4, 6-tetra (2-hydroxyethyl) glycoluril into a reaction bottle, stirring at room temperature, dropwise adding 11.75g of thionyl chloride, and refluxing for 2 hours after dropwise adding; cooling to 10 ℃, adding 10mL of water and 3.65g of thiourea, and continuously refluxing and stirring for reaction for 12 hours; then cooling to 25 ℃, dropwise adding 4.00g of 48% sodium hydroxide aqueous solution under nitrogen atmosphere, and stirring and reacting for 9 hours at 70 ℃; after cooling to 20 ℃ again, 3.50g of concentrated hydrochloric acid and 10mL of chloroform were added thereto, and the mixture was stirred for 30 minutes, followed by 1 st suction filtration, 10mL of chloroform was added to the resulting cake, and the mixture was stirred for 30 minutes, followed by 2 nd suction filtration. The filtrates from the two suction filtrations were combined to remove the aqueous layer, the organic layer was washed 5 times with 5mL of water, and the organic layer was concentrated under reduced pressure to give 3.1g of a yellow oil (crude product); separating and purifying the crude product by column chromatography (eluent: chloroform) to obtain 2.85g of white crystal (melting point: 75.3-77.8 deg.C), i.e. 1,3,4, 6-tetra (2-mercaptoethyl) glycoluril; in addition, 0.28g of a pale yellow oily substance was obtained, i.e., 1' - (dithiobisethanediyl) -bis [3,4, 6-tris (2-mercaptoethyl) glycoluril ] as a product, and the mercaptan equivalent was 127 g/eq;

the epoxy resin is bisphenol A type epoxy resin selected from EPICLON EXA-850CRP of DIC corporation, the epoxy equivalent is 170-175g/eq, and the structural formula is shown as formula (VIII):

bisphenol A epoxy monoacrylate is selected from EA-1010LC of Japan NK Oligo company, the epoxy equivalent is 412.5g/eq, and the structural formula is shown as formula (IX):

the acrylate compound is selected from epoxy acrylate CN121 and tricyclodecane dimethanol diacrylate SR833S from SARTOMER company;

the curing accelerator is latent curing agent selected from NOVACURE HXA9322HP of asahi chemical company;

the photoinitiator is 2-hydroxy-2-methyl-1-phenyl acetone and diphenyl- (2,4, 6-trimethyl benzoyl) oxyphosphorus, which are respectively selected from Irgacure 1173 from BASF company and Omnirad TPO from IGM company;

the polymerization inhibitor is p-hydroxyanisole selected from MEHQ of Solvay company;

the stabilizer is triisopropyl borate, and is selected from W330012 of Sahn chemical technology (Shanghai) Co., Ltd;

the silane coupling agent is gamma-methyl acrylate propyl trimethoxy silane selected from KBM503 of Japan shin-Etsu corporation;

the filler is fumed silica selected from aerosil r202 from Evonik corporation.

Test example

(1) Crystal precipitation time:

the resin compositions obtained in the above examples and comparative examples were allowed to stand at room temperature for a period of time from completion of the preparation of the resin compositions to confirmation of crystal precipitation. The crystal deposition was confirmed by visual observation, and the maximum time of the test was 240 hours. The results are shown in Table 3.

(2) Measurement of glass transition temperature:

the resin compositions obtained in the above examples and comparative examples were respectively stored for 240 hours at room temperature under sealed conditions, and then the resin compositions were respectively taken out and injected into a tetrafluoroethylene mold, and then were scraped off,using an ultraviolet light source (365nm, light intensity 1000 mW/cm)²) Irradiating and curing for 4 seconds, placing a sample in an oven at 80 ℃ for thermal curing for 60 minutes, preparing the completely cured resin composition into a sheet with the thickness of 42mm multiplied by 8mm multiplied by 0.3mm, testing by using a Q-800 type dynamic thermo-mechanical analysis tester of a American TA instrument, and measuring the change rule of a loss factor (tan delta) along with the temperature in a liquid nitrogen atmosphere and a film stretching mode within the temperature range of-40 to 250 ℃, wherein the temperature rise rate is 10 ℃/min, the testing frequency is 10Hz, and thus the glass transition temperature (DEG C) of the cured resin composition is determined. The results are shown in Table 3.

(3) Hot bonding strength:

respectively sealing, standing and storing the resin compositions obtained in the above examples and comparative examples for 240 hours at room temperature, then taking out the resin compositions, respectively coating the resin compositions on stainless steel sheets, laminating the stainless steel sheets by toughened glass sheets, wherein the area of the adhesive layer is 25.4mm multiplied by 5mm, and ensuring that the thickness of the adhesive layer is 0.1 mm; using an ultraviolet light source (365nm, light intensity 1000 mW/cm)²) Carrying out irradiation curing for 4 seconds, and then carrying out thermocuring on the sample at 80 ℃ for 60 minutes in an oven and a nitrogen atmosphere; pulling the two sheets apart in opposite directions by using a universal tester, testing at the ambient temperature of 85 ℃, and recording the measured force value, namely the thermal bonding strength immediately after sample preparation, as the strength (MPa); and (3) treating the cured sample for 150 hours at 85 ℃/85% RH under heating and humidifying conditions, and testing the shear bonding strength of the sample again under the condition that the environmental temperature is 85 ℃, namely the thermal bonding strength (MPa) after heating and humidifying. The results are shown in Table 3.

(4) Water absorption: preparing a sample of 3mm multiplied by 1.5mm from the completely cured resin composition, weighing and recording the sample, immersing the sample into deionized water at the temperature of 100 ℃, and carrying out constant temperature treatment for 2 hours; taking the sample out of the water, carefully absorbing the water attached to the surface of the sample by using filter paper, weighing the sample again and recording; the weight percentage increase of the sample before and after boiling was calculated as the water absorption (%). The results are shown in Table 3.

TABLE 3

When comparative examples 1 to 17 and/or comparative examples 1 to 5 are analyzed in conjunction with table 3, it can be seen that, first, by analyzing examples 1 to 8, the crystal precipitation time of the photo/thermal dual curable resin composition of the present invention exceeds the maximum test time of 240 hours, since the polythiol compound of the present invention is in a liquid state at room temperature, so that the resin composition is more stable in storage, thereby having a long pot life, and meanwhile, the polythiol compound of the present invention has no ester bond and is less in odor, the resin composition can be rapidly initially cured by UV light irradiation after being stored for 240 hours on standing, and then is continuously thermally cured at a milder temperature of 80 ℃ to achieve a high degree of crosslinking, the glass transition temperature exceeds 124 ℃, and the water absorption rate is within 2.2%, thereby exhibiting high heat resistance and good moisture barrier properties, the hot bonding strength of the cured product measured at the high temperature of 85 ℃ reaches more than 7.1MPa, and about 90 percent of the hot bonding strength can be maintained after a heating and humidifying test, which shows that the light/heat dual-curable resin composition has excellent bonding performance and resistance to wet-heat hydrolysis.

By comparing and analyzing examples 1 and 9 to 11, examples 5 and 12 to 14, the equivalent ratio of the thiol functional group of the polythiol compound to the epoxy functional group of the epoxy resin has no obvious influence on the storage stability and the heat and humidity resistance of the resin composition, the resin composition has no crystal precipitation within 240 hours, the reduction range of the thermal bonding strength of the resin composition before and after being cured by a heating and humidifying experiment is still relatively small, but the equivalent ratio of the thiol functional group to the epoxy functional group has a certain influence on the bonding performance of the resin composition, when the ratio is excessively large or excessively small, the thermal bonding strength of the resin composition after being cured is slightly reduced, but still reaches more than 6.8MPa, the glass transition temperature is also reduced to a certain extent, but still exceeds 118 ℃ on the whole, and the barrier performance of moisture is reduced to a certain extent, the water absorption rate is increased to be within 2.37-2.89%.

By comparing and analyzing example 1 and examples 15 to 16, it can be found that the storage stability of the resin composition is not affected but the glass transition temperature and the thermal bonding strength are both significantly reduced, the thermal bonding strength after the heating and humidifying test is also reduced to a certain extent, and the water absorption rate is increased to more than 2.9% after the replacing of the preferable acrylate compound combination of the present invention with the single acrylate compound, which shows that the preferable acrylate compound combination of the present invention has a significant effect on the heat resistance, the bonding performance, the moisture barrier performance and the wet-heat hydrolysis resistance of the light/heat dual curable resin composition.

By comparing and analyzing the example 1 and the example 17, it can be found that after the preferred epoxy resin combination of the present invention is replaced by the single bisphenol a type epoxy resin, the storage stability of the resin composition is not affected, but the glass transition temperature is lowered to 108 ℃, the thermal bonding strength is lowered to 6.45MPa, the thermal bonding strength after heating and humidifying experiments is also lowered to a certain extent, and the water absorption rate is raised to 2.98%, because the bisphenol a epoxy monoacrylate as another component in the preferred epoxy resin combination of the present invention has both epoxy functional groups and acrylate functional groups, the system compatibility between the UV light curing and the heat curing can be effectively increased, and the compatibility and the curing effect of the resin composition are affected after the bisphenol a epoxy monoacrylate is removed, thereby the overall performance is reduced, which shows that the heat resistance, the heat resistance and the heat curing effect of the light/heat dual curable resin composition of the preferred epoxy resin combination of the present invention, The adhesive property, the moisture barrier property and the resistance to wet heat hydrolysis have obvious influence.

By analyzing example 1, example 5 and comparative example 1 in comparison, it was found that, after the polythiol compound prepared by the present invention was replaced with pentaerythritol tetrakis (3-mercaptopropionate) ester having an ester bond, because pentaerythritol tetrakis (3-mercaptopropionate) ester is liquid at room temperature, the resin composition does not have crystal precipitation, the storage stability and the pot life are not greatly influenced, but the glass transition temperature of the cured product is sharply reduced to 64 ℃, the hot bonding strength is also reduced to 5.06MPa, the heat resistance and the bonding performance are both obviously reduced, meanwhile, the water absorption of a cured product is as high as 7.56 percent, and the hot bonding strength after a heating and humidifying test is almost completely lost, which shows that the polythiol compound without ester bonds has very critical influence on the heat resistance, the bonding performance, the moisture barrier performance and the wet-heat hydrolysis resistance of the photo/thermal dual-curable resin composition after curing;

by comparatively analyzing example 1, example 5 and comparative example 2, it was found that, after the polythiol compound prepared by the present invention was replaced with a bifunctional hybrid thiol compound represented by the formula (VII), since the thiol compound is liquid at room temperature, the resin composition is not crystallized, the storage stability and pot life are not greatly affected, but the glass transition temperature of the cured product is sharply reduced to 26 ℃, the thermal bonding strength is also reduced to 4.75MPa, the heat resistance and the thermal bonding performance are obviously reduced, meanwhile, the water absorption of the cured product is as high as 5.13%, and the hot bonding strength after heating and humidifying tests is obviously reduced, which further shows that the polythiol compound has very critical influence on the heat resistance, the bonding performance, the moisture barrier performance and the wet-heat hydrolysis resistance of the photo/thermal dual-curable resin composition after curing.

By comparing and analyzing the example 1, the example 5 and the comparative example 3, it can be found that after the polythiol compound prepared by the invention is replaced by the 1,3,4, 6-tetra (2-mercaptoethyl) glycoluril, because the pure polythiol compound is solid crystal at room temperature, the crystal precipitation time of the resin composition is greatly shortened to 12.5 hours, the glass transition temperature after curing is reduced to 87 ℃, the thermal bonding strength is reduced to 6.14MPa, and the water absorption rate also reaches 3.82 percent, which shows that the solid polythiol curing agent 1,3,4, 6-tetra (2-mercaptoethyl) glycoluril is easy to precipitate crystal after being stored for a period of time, and incomplete curing is easy to occur to cause the reduction of the comprehensive performance of the light/heat dual-curable resin composition.

By comparing and analyzing examples 1, 5 and 3 to 4, it can be seen that, although the problems of short crystal precipitation time and performance degradation of the solid polythiol compound 1,3,4, 6-tetrakis (2-mercaptoethyl) glycoluril can be improved by adding a partially liquid 1,1- (dithiobisethanediyl) -bis [3,4, 6-tris (2-mercaptoethyl) glycoluril ] in comparative example 4, this solution can significantly increase the cost, and the glass transition temperature, thermal bonding strength and water absorption rate after curing of the resin composition are still inferior to those of the resin compositions of examples 1 and 5 as a whole, which shows that the polythiol compound of the present invention can be used for storage stability of a photo/thermal dual curable resin composition at low cost without crystal precipitation, The heat resistance, adhesion properties, moisture barrier properties and resistance to wet heat hydrolysis have a significant influence.

By comparing and analyzing example 1 and comparative example 5, it can be found that after the preferred epoxy resin composition of the present invention is replaced with the single bisphenol a epoxy monoacrylate, while the acrylate compound is not used, the storage stability of the resin composition is not affected, but the glass transition temperature is further decreased to 102 ℃, the thermal bonding strength is greatly decreased to 5.07MPa, and the water absorption rate is increased to 3.45%, because the other component bisphenol a epoxy resin in the preferred epoxy resin composition of the present invention has a plurality of epoxy functional groups, which can increase the crosslinking degree and the bonding strength, and the substitution with the bisphenol a epoxy monoacrylate completely decreases the number of epoxy functional groups and the bonding strength, which decreases the overall performance, and the photo/thermal dual curing system can compensate the defect of the conventional single curing method, further illustrating the preferred epoxy resin composition of the present invention and the photo/thermal dual curing system to the resin composition The heat resistance, the adhesive property, the moisture barrier property and the resistance to wet heat hydrolysis of the adhesive have a significant influence.

In summary, the polythiol compound, the preferred acrylate compound combination and the preferred epoxy resin combination provided by the invention have obvious influence on the comprehensive performance of the light/heat dual-curable resin composition; the multifunctional group mercaptan compound adopted by the invention is liquid at room temperature, has no ester bond, small smell and low cost, and the corresponding light/heat dual-curing resin composition has no crystal precipitation in the storage process; the light/heat dual-curing resin composition provided by the invention has the advantages of small smell, low cost, good storage stability, capability of being quickly positioned by illumination, low-temperature thermocuring, improved bonding performance and the like, and simultaneously has high crosslinking degree, good moisture barrier performance, excellent heat resistance, bonding performance and humidity and heat hydrolysis resistance after curing, and can meet the application requirements of bonding or sealing in high-precision required fields such as electronic circuits, sensors or cameras.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made in the above embodiments by those of ordinary skill in the art without departing from the principle and spirit of the present invention.

Claims

1. A light/heat dual-curable resin composition is characterized by comprising 20-40 parts by weight of epoxy resin, 10-35 parts by weight of polythiol compound, 20-40 parts by weight of acrylate compound, 1-5 parts by weight of curing accelerator, 0.3-5 parts by weight of photoinitiator, 0.01-3 parts by weight of polymerization inhibitor and 0.1-3 parts by weight of stabilizer; the polythiol compound is represented by the general formula (I):

in the general formula (I), R¹、R²、R³And R⁴Wherein only one is a mercaptoalkoxy group having 2 to 5 carbon atoms, R⁵、R⁶、R⁷And R⁸Wherein only one is a mercaptoalkoxy group having 2 to 5 carbon atoms, R¹、R²、R³、R⁴、R⁵、R⁶、R⁷And R⁸The remaining six of (A) are each independently selected from one of a hydrogen atom, an alkyl group having 1 to 3 carbon atoms and a lower alkoxy group having 1 to 3 carbon atoms.

2. The photo/thermal dual curable resin composition according to claim 1, wherein the compound represented by the general formula (I)In the polythiol compound of (a), R¹、R²And R⁴One of them is a mercaptoalkoxy group having 2 to 5 carbon atoms and the other two are both hydrogen atoms, R³And R⁷Each independently selected from a hydrogen atom or a methoxy group, R⁵、R⁶And R⁸One of them is a mercaptoalkoxy group having 2 to 5 carbon atoms and the other two are both hydrogen atoms.

3. The photo/thermal dual curable resin composition according to claim 1, wherein R in the polythiol compound represented by the general formula (I) is R¹And R⁵Are each a hydrogen atom, R³And R⁷Each independently selected from a hydrogen atom or a methoxy group, R²And R⁴One of them is a mercaptoalkoxy group having 2 to 5 carbon atoms and the other is a hydrogen atom, R⁶And R⁸One of them is a mercaptoalkoxy group having 2 to 5 carbon atoms and the other is a hydrogen atom.

4. The photo/thermal dual curable resin composition according to claim 1, wherein R in the polythiol compound represented by the general formula (I) is R¹And R⁵Are each a hydrogen atom, R³And R⁷Each independently selected from a hydrogen atom or a methoxy group, and when R is²And R⁶When all are mercapto alkoxy groups having 2 to 5 carbon atoms, R⁴And R⁸Are each a hydrogen atom; when R is⁴And R⁸When all are mercapto alkoxy groups having 2 to 5 carbon atoms, R²And R⁶Are each a hydrogen atom; when R is⁴And R⁶When all are mercapto alkoxy groups having 2 to 5 carbon atoms, R²And R⁸Are each a hydrogen atom; when R is²And R⁸When all are mercapto alkoxy groups having 2 to 5 carbon atoms, R⁴And R⁶Are all hydrogen atoms.

5. The photo/thermal dual curable resin composition according to claim 1, wherein the polythiol compound is prepared by a method comprising:

6. The photo/thermal dual curable resin composition according to claim 5, wherein in the first step, the substitution reaction is performed by dissolving the biphenol compound represented by the general formula (II) in an organic solvent, adding alkali to provide alkaline conditions, adding a phase transfer catalyst, heating to 40-100 ℃ under the protection of inert gas, stirring for 10-60 minutes, adding the halogenated compound represented by the general formula (III), reacting for 4-12 hours, filtering the reaction solution, distilling the filtrate under reduced pressure to remove the solvent, washing with water for three times, extracting with chloroform, collecting the organic phase, and evaporating to dryness to obtain a first intermediate product which is colorless or pale yellow in liquid state.

7. The photo/thermal dual curable resin composition according to claim 5, wherein in the second step, the radical addition reaction is carried out by dissolving the first intermediate product in an organic solvent, adding a radical initiator, raising the temperature to 40-100 ℃ under the protection of an inert gas, slowly adding thioacetic acid, carrying out the radical addition reaction for 4-12 hours, and then distilling off the solvent under reduced pressure to obtain a second intermediate product which is liquid and colorless or pale yellow.

8. The photo/thermal dual curable resin composition of claim 5, wherein in the third step, the hydrolysis reaction is performed by dissolving the second intermediate product in an organic solvent, adding hydrochloric acid or sodium hydroxide, heating to 50-100 ℃ for reaction for 3-12 hours, distilling under reduced pressure to remove the solvent, washing twice with 2-8% sodium bicarbonate solution, extracting with chloroform, collecting the organic phase, and evaporating to dryness to obtain a colorless or pale yellow viscous liquid product, i.e., the polythiol compound.

9. The photo/thermal dual curable resin composition according to any one of claims 1 to 8, wherein the epoxy resin is an aromatic epoxy resin and/or an aliphatic epoxy resin.

10. The photo/thermal dual curable resin composition according to any one of claims 1 to 8, wherein the epoxy resin is a combination of a bisphenol A type epoxy resin and a bisphenol A epoxy monoacrylate in a weight ratio of 1 (0.3) to 0.9.

11. The photo/thermal dual curable resin composition according to any one of claims 1 to 8, wherein the ratio of the thiol functional group equivalent of the polythiol compound to the epoxy functional group equivalent of the epoxy resin is 0.5 to 2.0, preferably 0.8 to 1.2.

12. The photo/thermal dual curable resin composition according to any one of claims 1 to 8, wherein the acrylate compound is at least one selected from the group consisting of epoxy (meth) acrylate, urethane (meth) acrylate, polyester (meth) acrylate, polyether (meth) acrylate, silane-modified (meth) acrylate, polyol (meth) acrylate, polyolefin (meth) acrylate, melamine (meth) acrylate, and (meth) acrylated acrylic resin.

13. The light/heat dual curable resin composition according to any one of claims 1 to 8, wherein the acrylate compound is a combination of epoxy acrylate and tricyclodecane dimethanol diacrylate in a weight ratio of 1 (0.5-1.5).

14. The photo/thermal dual curable resin composition according to any one of claims 1 to 8, wherein the curing accelerator is at least one selected from the group consisting of imidazole-based curing accelerators, tertiary amine-based curing accelerators and phosphorus compound-based curing accelerators.

15. The photo/thermal dual curable resin composition according to any one of claims 1 to 8, wherein the photoinitiator is a radical photoinitiator; the free radical photoinitiator is a cracking type photoinitiator and/or a hydrogen abstraction type photoinitiator.

16. The light/heat dual curable resin composition according to any one of claims 1 to 8, wherein the polymerization inhibitor is at least one selected from hydroquinone, p-hydroxyanisole, p-benzoquinone, methylhydroquinone, 2-tert-butylhydroquinone, 2, 5-di-tert-butylhydroquinone, 4-hydroxypiperidinol oxyl, phenothiazine and anthraquinone.

17. The photo/thermal dual curable resin composition according to any one of claims 1 to 8, wherein the stabilizer is at least one selected from the group consisting of a liquid borate compound, an aluminum chelating agent and barbituric acid.

18. The photo/thermal dual curable resin composition according to any one of claims 1 to 8, further comprising a coupling agent and/or an auxiliary agent; the coupling agent is at least one selected from gamma- (2, 3-epoxypropoxy) propyltrimethoxysilane, beta- (3, 4-epoxycyclohexyl) ethyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 8-epoxypropoxytrimethoxysilane, gamma-mercaptopropyltrimethoxysilane, vinyltrimethoxysilane and vinyltriethoxysilane; the auxiliary agent is selected from at least one of filler, antioxidant, flame retardant, adhesion promoter, diluent, pigment, defoaming agent, leveling agent and ion trapping agent; the content of the coupling agent is 0.01-5 parts by weight; the content of the auxiliary agent is 0.01-30 parts by weight.

19. The method for preparing a photo/thermal dual curable resin composition according to any one of claims 1 to 18, wherein the method comprises uniformly mixing an epoxy resin, a polythiol compound, an acrylate compound, a curing accelerator, a photoinitiator, a polymerization inhibitor and a stabilizer, and optionally a coupling agent and/or an auxiliary agent under the condition of keeping out light to obtain the photo/thermal dual curable resin composition.

20. The method of claim 19, wherein the mixing is performed by stirring the acrylate compound, the photoinitiator and the polymerization inhibitor for 20-40 minutes at 20-30 ℃, a vacuum degree of-0.05 MPa to-0.1 MPa and a rotation speed of 40-60 rpm in a dark environment, adding the epoxy resin, the polythiol compound and the stabilizer for 20-40 minutes at 20-30 ℃, a vacuum degree of-0.05 MPa to-0.1 MPa and a rotation speed of 40-60 rpm, adding the curing accelerator and the optional silane coupling agent and the optional auxiliary agent, and further stirring for 20-40 minutes at 20-30 ℃, a vacuum degree of-0.05 MPa to-0.1 MPa and a rotation speed of 40-60 rpm, and (6) sealing and packaging in a dark place.

21. Use of the light/heat dual curable resin composition according to any one of claims 1 to 18 as an adhesive or a sealant for bonding or sealing of electronic parts.

22. Use of the light/heat dual curable resin composition according to any one of claims 1 to 18 as an adhesive or sealant for bonding or sealing of a sensor or a camera.