Epoxy resin adhesive for cutting silicon rod and method for preparing the same

Abstract

The present application provides a kind of epoxy resin adhesive for silicon rod cutting and its preparation method, the epoxy resin adhesive for silicon rod cutting includes A component and B component;The preparation raw materials of the A component include the following components: bisphenol A type epoxy resin, vinyl resin, toughened epoxy resin, filler, active diluent, anti-settling agent, defoaming agent;The preparation raw materials of the B component include the following components: curing agent, silane coupling agent containing unsaturated group, silane coupling agent containing saturated group, alicyclic amine, accelerator, filler, anti-settling agent, defoaming agent;The filler in the A component and B component all includes cutting silicon powder.The epoxy resin adhesive for silicon rod cutting provided by the present application has excellent colloidal bonding strength, water resistance, degumming performance, and suitable curing peak temperature, hardness peak, temperature resistance.

Description

Technical Field

[0001] This invention belongs to the field of epoxy resin adhesive technology, and relates to an epoxy resin adhesive for silicon rod cutting and its preparation method, particularly to a high-adhesion epoxy resin adhesive for silicon rod cutting and its preparation method. Background Technology

[0002] Silicon wafers are not only upstream materials for photovoltaic cells, but also key materials for high-end semiconductor devices. With the soaring price of upstream silicon materials, the thinning of solar cells has become an inevitable trend. Therefore, the technology of cutting silicon rods into silicon wafers needs to be further optimized. In the process of cutting silicon rods, the bonding between silicon rods and silicon wafers is extremely important, as it relates to the rating of silicon wafers after cutting and the manufacturing process of solar cells. The material for bonding silicon rods and substrates is an adhesive with epoxy resin as the main resin. Currently, the adhesives used for cutting silicon rods have problems such as excessive strength and insufficient bonding, and there is a possibility of wafer falling off during the cutting process. The two most intuitive ways to improve the bonding strength of the adhesive are as follows: (1) increase the crosslinking density of the colloidal system; (2) add tackifiers / tackifying resins. While existing technologies can improve strength by introducing modified amines or higher-functionality epoxy resins to increase crosslinking density, excessive hardness after curing can lead to excessive cutting stress when the diamond wire cuts to the bottom of the silicon rod, causing localized edge chipping of the silicon wafer, reducing yield, and affecting wafer rating, i.e., wafer production rate. Furthermore, increasing crosslinking density results in a high density of three-dimensional molecular network structures per unit volume, leading to excessive heat release during curing, excessive internal stress in the cured material, and localized cracking. This reduces the mechanical strength of the adhesive after curing, thus lowering the bond strength. Although current technologies can improve bond strength by increasing the amount of coupling agent (tackifier), the hydrophobic nature of coupling agents compared to thiols slows down debonding, thus reducing the cutting efficiency of the production line.

[0003] CN109880567A discloses a diamond wire silicon wafer adhesive and its preparation method, comprising: Component A: glycidyl ester type epoxy resin, general-purpose bisphenol A epoxy resin, glycidyl ether, filler, defoamer, anti-settling agent, and coupling agent; Component B: modified polythiol, self-made m-phenylenediamine prepolymer, accelerator, filler, defoamer, and anti-settling agent. This invention improves upon existing adhesives by providing a diamond wire silicon wafer adhesive and its preparation method. It achieves degumming without acid by boiling without adding degumming agents, and the degumming temperature is 10°C lower than existing degumming methods. Furthermore, it reduces the conductivity of the solution in the cooling water or degumming water, ensuring the normal operation of the cooling water circulation system, extending the machine's service life, guaranteeing factory production efficiency, and resolving potential safety hazards related to machine malfunctions. However, the bonding strength of the adhesive provided by this invention still needs further improvement.

[0004] Therefore, it is desirable in the art to develop an epoxy resin adhesive for cutting silicon rods that has excellent adhesive strength. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide an epoxy resin adhesive for silicon rod cutting and its preparation method.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides an epoxy resin adhesive for cutting silicon rods, the epoxy resin adhesive for cutting silicon rods comprising component A and component B;

[0008] The raw materials for preparing component A include the following components: bisphenol A type epoxy resin, vinyl resin, toughened epoxy resin, filler, reactive diluent, anti-settling agent, and defoamer;

[0009] The raw materials for preparing component B include the following components: curing agent, silane coupling agent containing unsaturated groups, silane coupling agent containing saturated groups, alicyclic amine, accelerator, filler, anti-settling agent, and defoamer;

[0010] The fillers in both component A and component B include diced silicon powder.

[0011] In this invention, both component A and component B contain silicon powder (i.e., silicon powder generated during the silicon rod cutting process). According to the principle of similar compatibility, the colloid with added silicon powder has excellent compatibility and better wettability with the silicon rod, which greatly improves the adsorption capacity of the adhesive to the silicon rod, thereby improving the adhesion to the silicon rod. At the same time, silicon powder can also reduce the exothermic temperature of the epoxy resin during the curing reaction, thereby eliminating the internal stress of the cured product and preventing it from cracking, achieving two benefits in one step.

[0012] In this invention, component A contains a high crosslinking density vinyl resin with unsaturated groups, and component B contains a silane coupling agent with unsaturated groups. The reaction between the two can increase the crosslinking density of the colloid and the molecular density per unit area between the colloid and the silicon rod, thus ensuring the strength of the colloid and improving the bonding strength of the system.

[0013] In this invention, the addition of toughened epoxy resin is intended to compensate for the problem of colloid cracking caused by excessively high crosslinking density and excessively high local temperature rise during the curing process. During the cutting process, edge chipping of the colloid will also occur, and the silicon wafer will also chip or fall off. This type of toughened resin has a low glass transition temperature. During the diamond wire cutting process, friction generates heat, and the local temperature is too high, causing the colloid to soften locally. The hardness of the system will decrease accordingly, increasing the local mechanical internal stress, which can more effectively ensure the bonding strength between the colloid and the silicon wafer, thereby improving the silicon wafer yield. At the same time, during the acid boiling degumming process, the colloid will also soften more quickly, which can improve the degumming efficiency of the colloid, thereby improving the cutting efficiency of the production line.

[0014] Specifically, this invention, by selecting specific components, enables the prepared epoxy resin adhesive for silicon rod cutting to: ① exhibit a suitable exothermic peak value during curing; ② possess excellent system adhesive strength peak value after complete curing, resulting in stronger adhesion; ③ exhibit a suitable hardness reduction rate and peak value during cutting (greater and faster hardness reduction during cutting, ensuring no edge chipping and high silicon wafer yield), as well as good water resistance; and ④ have a high adhesive debonding rate during debonding, improving the efficiency of the silicon rod cutting process. Furthermore, in the face of rising silicon material prices upstream, this invention can facilitate the reuse of waste materials.

[0015] Preferably, the raw materials for preparing component A, by weight, include the following components:

[0016]

[0017] The raw materials for preparing component B, by weight, include the following components:

[0018]

[0019] Preferably, the amount of bisphenol A epoxy resin used in the preparation of component A can be 35 parts, 40 parts, 45 parts, 50 parts, 55 parts, or 60 parts by weight.

[0020] Preferably, the amount of vinyl resin used in the preparation of component A, by weight, can be 5 parts, 5.5 parts, 6 parts, 6.5 parts, 7 parts, 7.5 parts, 8 parts, 8.5 parts, 9 parts, 9.5 parts, or 10 parts, etc.

[0021] Preferably, the amount of toughened epoxy resin used in the preparation of component A can be 5 parts, 5.5 parts, 6 parts, 6.5 parts, 7 parts, 7.5 parts, 8 parts, 8.5 parts, 9 parts, 9.5 parts, or 10 parts by weight.

[0022] Preferably, the amount of silicon powder used in the preparation of component A, by weight, can be 20 parts, 21 parts, 22 parts, 23 parts, 24 parts, 25 parts, 26 parts, 27 parts, 28 parts, 29 parts, 30 parts, 31 parts, 32 parts, 33 parts, 34 parts, or 35 parts, etc.

[0023] Preferably, the amount of active diluent used in the preparation of component A, by weight, can be 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, or 0.5 parts, etc.

[0024] Preferably, the amount of anti-settling agent used in the preparation of component A, by weight, can be 0.01 parts, 0.03 parts, 0.05 parts, 0.08 parts, 0.1 parts, 0.5 parts, 1 part, 1.5 parts, or 2 parts, etc.

[0025] Preferably, the amount of defoamer used in the preparation of component A, by weight, can be 0.01 parts, 0.03 parts, 0.05 parts, 0.08 parts, 0.1 parts, 0.5 parts, or 1 part, etc.

[0026] Preferably, the amount of curing agent used in the preparation of component B, by weight, can be 40 parts, 45 parts, 50 parts, 55 parts, or 60 parts, etc.

[0027] Preferably, the amount of silane coupling agent containing unsaturated groups used in the preparation of component B, by weight, can be 0.05 parts, 0.08 parts, 0.1 parts, 0.5 parts, 0.8 parts, 1 part, 1.3 parts, 1.5 parts, 1.8 parts, or 2 parts, etc.

[0028] Preferably, the amount of silane coupling agent containing saturated groups used in the preparation of component B, based on parts by weight, can be 0.05 parts, 0.08 parts, 0.1 parts, 0.5 parts, or 1 part, etc.

[0029] Preferably, the amount of alicyclic amine used in the preparation of component B, by weight, can be 0.05 parts, 0.08 parts, 0.1 parts, 0.5 parts, or 1 part, etc.

[0030] Preferably, the amount of accelerator used in the preparation of component B, based on parts by weight, can be 1 part, 2 parts, 3 parts, 4 parts, 5 parts, or 6 parts, etc.

[0031] Preferably, the amount of silicon powder used in the preparation of component B, by weight, can be 20 parts, 21 parts, 22 parts, 23 parts, 24 parts, 25 parts, 26 parts, 27 parts, 28 parts, 29 parts, 30 parts, 31 parts, 32 parts, 33 parts, 34 parts, or 35 parts, etc.

[0032] Preferably, the amount of anti-settling agent used in the preparation of component B, by weight, can be 0.01 parts, 0.03 parts, 0.05 parts, 0.08 parts, 0.1 parts, 0.5 parts, 1 part, or 1.5 parts, etc.

[0033] Preferably, the amount of defoamer used in the preparation of component B, by weight, can be 0.01 parts, 0.03 parts, 0.05 parts, 0.08 parts, 0.1 parts, 0.5 parts, or 1 part, etc.

[0034] In this invention, if there is too much silicon powder in components A and B, the viscosity of the adhesive is too high, making it difficult to mix. After mixing, the adhesive is difficult to apply, which reduces construction efficiency. The adhesive layer is too thick overall after application, which is not conducive to diamond wire cutting. If there is too little silicon powder in components A and B, the viscosity of the adhesive is too low. After mixing and applying the adhesive, the surface tension of the adhesive is low, making it easy to flow. The thickness of the adhesive layer between the bonding plate and the silicon rod is uneven, which cannot completely protect the silicon wafer and reduces the yield of silicon wafers.

[0035] Preferably, the mass ratio of component A to component B is 1:(0.8-1), for example 1:0.8, 1:0.9, 1:1 or the like.

[0036] Preferably, the bisphenol A type epoxy resin includes any one or a combination of at least two of commercially available general liquid types E-20, E-44, E-51, E-54 or E-56, and more preferably any one or a combination of at least two of E-51, E-54 or E-56.

[0037] Preferably, the vinyl resin is a high cross-linking density epoxy vinyl resin synthesized by modification with methacrylic acid and phenolic resin, with an average functionality ≥4, such as 4, 5 or 6.

[0038] Preferably, the vinyl resin includes any one or a combination of at least two of commercially available Hetron 970, Ripoxy 600, Swancor 977, or Dion 9700.

[0039] Preferably, the toughened epoxy resin is butadiene-acrylonitrile (CTBN) modified bisphenol A diglycidyl ether (DGEBA) epoxy resin.

[0040] Preferably, the toughened epoxy resin has an epoxy value ≥190 (e.g., 190, 195, or 200), including any one or a combination of at least two of commercially available RA840, RA95, or RA1340.

[0041] Preferably, the purity of the diced silicon powder in components A and B is ≥99%, such as 99%, 99.1%, 99.2%, 99.3%, 99.5%, 99.8%, or 99.9%.

[0042] Preferably, the dicing silicon powder in component A and component B each independently includes any one or a combination of at least two of the dicing silicon powder with a mesh size of 2000 mesh, 3000 mesh, or 4000 mesh.

[0043] Preferably, the reactive diluent is a reactive diluent containing monofunctional or polyfunctional epoxy groups, including any one or a combination of at least two of 1,4-butanediol diglycidyl ether (622), 1,6-hexanediol diglycidyl ether (632), C1-14-tetradecyl glycidyl ether (AGE), glycerol triglycidyl ether (633), or pentaerythritol tetraglycidyl ether (671), preferably any one or a combination of at least two of 622, 632, or 633.

[0044] Preferably, the curing agent is a commercially available modified polythiol with a conventional active hydrogen equivalent of 150 to 280, including any one or a combination of at least two of GPM830, GPM3800, GPM3380, GPM3385, R-2021 or R-2022, and more preferably any one or a combination of at least two of GPM830, GPM3385 or R-2021.

[0045] Preferably, the silane coupling agent containing unsaturated groups includes γ-methacryloxypropyltrimethoxysilane (KH570) and / or γ-methacryloxypropyltriethoxysilane.

[0046] Preferably, the silane coupling agent containing saturated groups includes γ-(2,3-epoxypropoxy)propyltrimethoxysilane and / or γ-(2,3-epoxypropoxy)propyltriethoxysilane (KH560).

[0047] Preferably, the alicyclic amine has an amine value ≥300mgKOH / g, such as 300mgKOH / g, 310mgKOH / g, 320mgKOH / g, or 350mgKOH / g.

[0048] Preferably, the accelerator comprises any one or a combination of at least two of 2,4,6-tris(dimethylaminomethyl)phenol (DMP-30), pyridine, triethylamine, resorcinol, m-cresol, or phenol, and more preferably any one or a combination of at least two of DMP-30, triethylamine, or resorcinol.

[0049] Preferably, the anti-settling agents in components A and B each independently comprise any one or a combination of at least two of fumed silica, organobentonite, or hydrogenated castor oil.

[0050] Preferably, the defoamers in components A and B independently include silicone-based defoamers.

[0051] Secondly, the present invention provides a method for preparing the epoxy resin adhesive for cutting silicon rods as described in the first aspect, the method comprising the following steps:

[0052] (1) Under vacuum conditions, bisphenol A type epoxy resin, vinyl resin, toughened epoxy resin and anti-settling agent are mixed, then filler is added, then reactive diluent and defoamer are added and mixed to obtain component A;

[0053] (2) Under vacuum conditions, the curing agent and anti-settling agent are mixed, then filler is added, and then silane coupling agent containing unsaturated groups, silane coupling agent containing saturated groups, alicyclic amine, accelerator and defoamer are added and mixed to obtain component B.

[0054] (3) Mix component A and component B to obtain the epoxy resin adhesive for cutting silicon rods.

[0055] As a preferred embodiment of the present invention, the preparation method includes the following steps:

[0056] (1) Under vacuum conditions, bisphenol A type epoxy resin, vinyl resin, toughened epoxy resin and anti-settling agent are added to a planetary mixer in sequence and mixed evenly. Then, filler is added in 3 batches (1 / 3 of the total filler amount each time) and dispersed and mixed until there are no agglomerated particles. Then, reactive diluent and defoamer are added in sequence and mixed evenly to obtain component A.

[0057] (2) Under vacuum conditions, add curing agent and anti-settling agent in sequence and mix evenly. Add filler in 3 batches (1 / 3 of the total filler amount each time) and disperse and mix until there are no agglomerated particles. Then add silane coupling agent containing unsaturated groups, silane coupling agent containing saturated groups, alicyclic amine, accelerator and defoamer in sequence and mix evenly to obtain component B.

[0058] (3) Mix component A and component B evenly to obtain the epoxy resin adhesive for cutting silicon rods.

[0059] Compared with the prior art, the present invention has at least the following beneficial effects:

[0060] (1) In this invention, both component A and component B contain silicon powder (i.e. silicon powder generated during the silicon rod cutting process). According to the principle of similar compatibility, the colloid with silicon powder has good compatibility with silicon rod and better wettability, which greatly improves the adsorption capacity of the adhesive to silicon rod, thereby improving the adhesion to silicon rod. At the same time, silicon powder can also reduce the exothermic temperature of epoxy resin during curing reaction, thereby eliminating the internal stress of the cured material and preventing it from cracking, achieving two benefits in one.

[0061] (2) In this invention, a high cross-linking density vinyl resin containing unsaturated groups is introduced into component A, and a silane coupling agent containing unsaturated groups is introduced into component B. The reaction between the two can increase the cross-linking density of the colloid and increase the molecular density per unit area between the colloid and the silicon rod, thus ensuring the strength of the colloid and improving the bonding strength of the system.

[0062] (3) In this invention, the addition of toughened epoxy resin is intended to compensate for the problem of excessive cross-linking density of the colloid and excessive local temperature rise during the curing process, which leads to cracking of the colloid. During the cutting process, the colloid will also chip at the edge, and the silicon wafer will also chip or fall off. This type of tough resin has a low glass transition temperature. During the diamond wire cutting process, friction generates heat and the local temperature is too high, causing the colloid to soften locally. The hardness of the system will decrease accordingly, increasing the local mechanical internal stress, which can more effectively ensure the bonding strength between the colloid and the silicon wafer, that is, improve the yield of silicon wafers. At the same time, during the acid boiling degumming process, the colloid will also soften faster, which can improve the degumming efficiency of the colloid, that is, improve the cutting efficiency of the production line. Detailed Implementation

[0063] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0064] The following is some information about the raw materials used in the embodiments and comparative examples of this invention:

[0065] Defoamer: Brand name BYK-077;

[0066] Alicyclic amines: brand name HXDA.

[0067] Example 1

[0068] This embodiment provides an epoxy resin adhesive for cutting silicon rods, which includes component A and component B in a mass ratio of 1:1.

[0069] The raw materials for preparing component A, by weight, include the following components:

[0070] 40 parts E-51 epoxy resin, 5 parts Hetron 970 vinyl resin, 5 parts toughened epoxy resin RA840, 25 parts 2000 mesh diced silica powder, 0.2 parts reactive diluent 622, 0.1 parts anti-settling agent fumed silica, and 0.2 parts defoamer;

[0071] The raw materials for preparing component B, by weight, include the following components:

[0072] Curing agent GMP830 45 parts, coupling agent KH-570 0.5 parts, KH-560 0.3 parts, alicyclic amine 0.5 parts, accelerator DMP-30 3 parts, 2000 mesh silicon powder 30 parts, defoamer 0.15 parts, anti-settling agent fumed silica 0.3 parts.

[0073] The preparation method includes the following steps:

[0074] (1) Under vacuum conditions, the bisphenol A type epoxy resin (E-51 epoxy resin), vinyl resin, toughening epoxy resin and anti-settling agent are added to a planetary mixer in sequence and mixed evenly. Then, filler is added in 3 batches (1 / 3 of the total filler amount is added each time) and dispersed and mixed until there are no agglomerated particles. Then, reactive diluent and defoamer are added in sequence and mixed evenly. The product is discharged to obtain component A.

[0075] (2) Under vacuum conditions, add the curing agent and anti-settling agent in the formula amount in sequence, mix evenly, add filler in 3 batches (1 / 3 of the total filler amount each time) and disperse and mix until there are no agglomerated particles. Then add silane coupling agent (KH-570) containing unsaturated groups, silane coupling agent (KH-560) containing saturated groups, alicyclic amine, accelerator and defoamer in sequence, mix evenly, discharge the material to obtain component B;

[0076] (3) Mix component A and component B in a certain proportion to obtain the epoxy resin adhesive for cutting silicon rods.

[0077] Example 2

[0078] This embodiment provides an epoxy resin adhesive for cutting silicon rods, which comprises component A and component B in a mass ratio of 1:0.9.

[0079] The raw materials for preparing component A, by weight, include the following components:

[0080] The mixture contains 50 parts of E-51 and E-54 epoxy resins (in a mass ratio of 2:3), 6 parts of Ripoxy 600 vinyl resin, 5 parts of toughened epoxy resin RA95, 25 parts of 3000-mesh diced silica powder, 0.3 parts of reactive diluent 632, 0.2 parts of hydrogenated castor oil as an anti-settling agent, and 0.05 parts of defoamer.

[0081] The raw materials for preparing component B, by weight, include the following components:

[0082] Curing agent 3385 48 parts, coupling agent KH-570 1 part, KH-560 0.6 parts, alicyclic amine 0.6 parts, accelerator triethylamine 5 parts, 3000 mesh silicon powder 25 parts, defoamer 0.2 parts, anti-settling agent organic bentonite 0.1 parts.

[0083] The preparation method can be referred to in Example 1.

[0084] Example 3

[0085] This embodiment provides an epoxy resin adhesive for cutting silicon rods, which includes component A and component B in a mass ratio of 1:0.8.

[0086] The raw materials for preparing component A, by weight, include the following components:

[0087] The mixture contains 60 parts of E-54 and E-56 epoxy resin (in a mass ratio of 3:2), 10 parts of Swancor 977 vinyl resin, 8 parts of toughened epoxy resin RA1340, 35 parts of 4000-mesh diced silica powder, 0.5 parts of reactive diluents 633 and 622 (in a mass ratio of 1:1), 0.5 parts of fumed silica (an anti-settling agent), and 0.8 parts of defoamer.

[0088] The raw materials for preparing component B, by weight, include the following components:

[0089] The mixture contains 55 parts of curing agent R-2021 and GPM830 (in a mass ratio of 2:1), 1.2 parts of coupling agent KH-570, 1 part of coupling agent KH-560, 0.8 parts of cycloaliphatic amine, 6 parts of accelerator DMP-30, 30 parts of 4000-mesh diced silica powder, 0.5 parts of defoamer, and 0.7 parts of anti-settling agent hydrogenated castor oil.

[0090] The preparation method can be referred to in Example 1.

[0091] Example 4

[0092] This embodiment provides an epoxy resin adhesive for cutting silicon rods, which comprises component A and component B in a mass ratio of 1:0.9.

[0093] The raw materials for preparing component A, by weight, include the following components:

[0094] 35 parts of E-51, E-56 and E-54 epoxy resins in a mass ratio of 2:2:1; 5.5 parts of Hetron 970 and Dion 9700 vinyl resins in a mass ratio of 1:1; 6.5 parts of toughened epoxy resins RA840 and RA95 in a mass ratio of 2:1; 20 parts of 3000 mesh and 4000 mesh diced silica powder in a mass ratio of 1:1; 0.1 parts of reactive diluents 622, 632 and 633 in a mass ratio of 1:1:1; 0.05 parts of anti-settling agent organic bentonite; and 0.03 parts of defoamer.

[0095] The raw materials for preparing component B, by weight, include the following components:

[0096] The mixture contains 40 parts of curing agent 3385 and GPM830 in a 1:1 mass ratio, 0.3 parts of coupling agent KH-570, 0.2 parts of coupling agent KH-560, 0.3 parts of alicyclic amine, 4 parts of accelerator resorcinol and DMP-30 in a 1:2 mass ratio, 25 parts of 3000 mesh and 4000 mesh cutting silicon powder in a 1:1 mass ratio, 0.04 parts of defoamer, and 0.05 parts of anti-settling agent hydrogenated castor oil.

[0097] The preparation method can be referred to in Example 1.

[0098] Example 5

[0099] The only difference between this embodiment and Embodiment 2 is that the 3000-mesh cut silicon powder in the raw materials of both component A and component B is replaced with an equal weight of 2000-mesh cut silicon powder.

[0100] Example 6

[0101] The only difference between this embodiment and Embodiment 2 is that the 3000-mesh cut silicon powder in the raw materials of components A and B is replaced with an equal weight of 4000-mesh cut silicon powder.

[0102] Comparative Example 1

[0103] The only difference between this comparative example and Example 2 is that the raw materials for preparing component A do not include toughened epoxy resin.

[0104] Comparative Example 2

[0105] The only difference between this comparative example and Example 2 is that the raw materials for preparing component A do not include vinyl resin.

[0106] Comparative Example 3

[0107] The only difference between this comparative example and Example 2 is that the raw materials for preparing component A do not include toughened epoxy resin and vinyl resin.

[0108] Comparative Example 4

[0109] The only difference between this comparative example and Example 2 is that the diced silicon powder in the raw materials of components A and B is replaced with an equal amount of silicon micro powder (grade TY600, particle size 5000 mesh).

[0110] Comparative Example 5

[0111] The diamond wire silicon wafer adhesive and preparation method disclosed in Example 2 of CN 109880567A were used for preparation.

[0112] The performance of the epoxy resin adhesive for silicon rod cutting provided in the examples and comparative examples was tested using the following methods:

[0113] (1) Peak curing temperature of colloid

[0114] After mixing components A and B of the colloid in a certain proportion, the center temperature of the colloid is monitored every 30 seconds using an infrared thermometer until the temperature of the colloid no longer rises, which is the peak curing temperature of the colloid.

[0115] (2) Hardness and bond strength test

[0116] Hardness testing was conducted in accordance with GB / T 531.1 standard; adhesive strength testing was conducted in accordance with GB / T 7124 standard. The specific testing method was to prepare a shear sample from the mixed colloid and test the adhesive strength after curing for 3 hours.

[0117] (3) Colloidal water resistance test

[0118] After mixing components A and B of the colloid in a certain proportion, apply it evenly to the bonding substrate. Use a thickness gauge to control the colloid thickness between 0.3mm and 0.5mm. After curing for 3 hours, use a utility knife to evenly cut the cured colloid layer into strips with a width of 0.2mm. Soak the strips in 15% cutting fluid for 2 hours and observe whether the colloid bubbles or delaminates.

[0119] (4) Colloid temperature resistance test

[0120] After mixing components A and B of the colloid in a certain proportion and curing for 3 hours, the colloid was placed in an environment of 65°C. The hardness change of the colloid was monitored with a hardness agent, and the minimum decrease in hardness and the time required for the decrease were recorded.

[0121] (5) Colloid degumming performance test

[0122] After mixing components A and B of the colloid in the specified ratio, the mixture was evenly applied to the bonding substrate. After curing for 3 hours and then resting for 2 hours, the cured colloid layer was evenly divided into 0.2 mm wide strips using a utility knife. The strips were then placed in a 55°C degreasing solution, and the time it took for the colloid to completely detach from the bonding substrate was recorded.

[0123] The performance test results are shown in Table 1.

[0124] Table 1

[0125]

[0126] As can be seen from Table 1, the epoxy resin adhesives for silicon rod cutting provided in Examples 1-6 of this invention all exhibit excellent colloidal bonding strength (26.3-28.4 MPa), water resistance (no bubbling or delamination after immersion in 15% cutting fluid for 2 hours), delamination performance (delamination time: 4.8-6.3 min), and suitable peak curing temperature (53-58℃) and peak hardness (86-91 H). D ), temperature resistance.

[0127] The comparison between Examples 5-6 and Example 2 shows that the mesh size of the cutting powder is positively correlated with the bonding strength (26.3-27.7 MPa) and negatively correlated with the debonding time (5.9-6.3 min). However, the actual test values ​​are not significantly different. Therefore, cutting powder with a mesh size of 2000-4000 is suitable for colloidal formulations.

[0128] As can be seen from the comparison between the examples and Comparative Example 5, the addition of cutting silicon powder can significantly improve the adhesive strength of the colloid and absorb the heat released during the curing of the colloid, thereby reducing the peak curing temperature of the colloid. At the same time, the cutting powder can also reduce the debonding time. After adding toughening epoxy resin, the hardness of the colloid decreases faster, which is more conducive to improving the internal stress of the colloid.

[0129] The comparison between Example 2 and Comparative Example 1 shows that without the addition of toughening epoxy resin, the system hardness decreases slowly, the debonding speed is slow, and the adhesive strength is slightly reduced. The comparison between Example 2 and Comparative Example 2 shows that without the addition of vinyl ester resin, the system hardness peak is low, and the adhesive strength is slightly reduced. The comparison between Example 2 and Comparative Example 3 shows that the above conclusions can also be drawn without the addition of toughening epoxy resin and vinyl ester resin. The comparison between Example 2 and Comparative Example 4 shows that after adding conventional silica powder, the adhesive strength decreases, the curing peak temperature increases significantly, and the debonding speed is slow, fully demonstrating that the cutting powder can improve the adhesive strength and absorb the exothermic effect of adhesive curing.

[0130] The applicant declares that this invention illustrates the epoxy resin adhesive for silicon rod cutting and its preparation method through the above embodiments, but the invention is not limited to the above embodiments, that is, it does not mean that the invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of the raw materials of the product, addition of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of this invention.

Claims

1. An epoxy resin adhesive for cutting a silicon rod, characterized by comprising: a curing agent; a curing accelerator; a silane coupling agent; and a silane coupling agent. The epoxy resin adhesive for cutting silicon rods includes component A and component B; The raw materials for preparing component A, by weight, include the following components: 35-60 parts of bisphenol A type epoxy resin, 5-10 parts of vinyl resin, 5-10 parts of toughened epoxy resin, 20-35 parts of diced silica powder, 0.1-0.5 parts of reactive diluent, 0.01-2 parts of anti-settling agent, and 0.01-1 parts of defoamer; The raw materials for preparing component B, by weight, include the following components: 40-60 parts of curing agent, 0.05-2 parts of silane coupling agent containing unsaturated groups, 0.05-1 parts of silane coupling agent containing saturated groups, 0.05-1 parts of alicyclic amine, 1-6 parts of accelerator, 20-35 parts of diced silicon powder, 0.01-1.5 parts of anti-settling agent, and 0.01-1 parts of defoamer.

2. The epoxy resin adhesive for cutting a silicon rod according to claim 1, characterized by The mass ratio of component A to component B is 1:(0.8-1).

3. The epoxy resin adhesive for cutting a silicon rod according to claim 1, characterized by The bisphenol A type epoxy resin includes any one or a combination of at least two of E-20, E-44, E-51, E-54 or E-56.

4. The epoxy resin adhesive for cutting a silicon rod according to claim 1, characterized by The average functionality of the vinyl resin is ≥4.

5. The epoxy resin bonding agent for cutting a silicon rod according to claim 1, characterized by The vinyl resin includes any one or a combination of at least two of Hetron 970, Ripoxy 600, Swancor 977, or Dion 9700.

6. The epoxy resin bonding agent for cutting a silicon rod according to claim 1, characterized by The toughened epoxy resin is butadiene-acrylonitrile modified bisphenol A diglycidyl ether epoxy resin.

7. The epoxy resin adhesive for silicon rod cutting according to claim 1, characterized in that, The toughened epoxy resin has an epoxy value ≥190, ​​including any one or a combination of at least two of RA840, RA95 or RA1340.

8. The epoxy resin adhesive for silicon rod cutting according to claim 1, characterized in that, The purity of the diced silicon powder in components A and B is ≥99%.

9. The epoxy resin adhesive for silicon rod cutting according to claim 1, characterized in that, The cutting silicon powder in component A and component B each independently includes any one or a combination of at least two of the cutting silicon powders with a mesh size of 2000 mesh, 3000 mesh, or 4000 mesh.

10. The epoxy resin adhesive for silicon rod cutting according to claim 1, characterized in that, The active diluent includes any one or a combination of at least two of the following: 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, C16-tetradecyl glycidyl ether, glycerol triglycidyl ether, or pentaerythritol tetraglycidyl ether.

11. The epoxy resin adhesive for silicon rod cutting according to claim 1, characterized in that, The curing agent includes any one or a combination of at least two of GPM830, GPM3800, GPM3380, GPM3385, R-2021 or R-2022.

12. The epoxy resin adhesive for silicon rod cutting according to claim 1, characterized in that, The silane coupling agents containing unsaturated groups include γ-methacryloxypropyltrimethoxysilane and / or γ-methacryloxypropyltriethoxysilane.

13. The epoxy resin adhesive for silicon rod cutting according to claim 1, characterized in that, The silane coupling agents containing saturated groups include γ-(2,3-epoxypropoxy)propyltrimethoxysilane and / or γ-(2,3-epoxypropoxy)propyltriethoxysilane.

14. The epoxy resin adhesive for silicon rod cutting according to claim 1, characterized in that, The amine value of the alicyclic amine is ≥300 mg KOH / g.

15. The epoxy resin adhesive for silicon rod cutting according to claim 1, characterized in that, The accelerator includes any one or a combination of at least two of 2,4,6-tris(dimethylaminomethyl)phenol, pyridine, triethylamine, resorcinol, m-cresol, or phenol.

16. A method for preparing an epoxy resin adhesive for cutting silicon rods as described in any one of claims 1-15, characterized in that, The preparation method includes the following steps: (1) Under vacuum conditions, bisphenol A type epoxy resin, vinyl resin, toughened epoxy resin and anti-settling agent are mixed, then cut silicon powder is added, then reactive diluent and defoamer are added and mixed to obtain component A; (2) Under vacuum conditions, the curing agent and anti-settling agent are mixed, then the diced silicon powder is added, and then the silane coupling agent containing unsaturated groups, the silane coupling agent containing saturated groups, the alicyclic amine, the accelerator, and the defoamer are added and mixed to obtain component B; (3) Mix component A and component B to obtain the epoxy resin adhesive for cutting silicon rods.

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