High-adhesion polyvinyl chloride adhesive for electronic components and preparation process of high-adhesion polyvinyl chloride adhesive

Abstract

The invention belongs to the technical field of polyvinyl chloride adhesives, and particularly relates to a high-adhesion polyvinyl chloride adhesive for an electronic element and a preparation process of the high-adhesion polyvinyl chloride adhesive. The polyvinyl chloride adhesive is prepared from the following raw material components: 80 to 100 parts of modified polyvinyl chloride, 10 to 20 parts of ethylene-acetic ether copolymer, 5 to 10 parts of plasticizer, 60 to 100 parts of diluent, 5 to 15 parts of filler, 0.5 to 3 parts of antioxidant and 0.5 to 2 parts of ultraviolet screening agent. The polyvinyl chloride adhesive obtained by the invention has excellent bonding strength and high temperature resistance.

Description

Technical Field

[0001] The invention belongs to the technical field of polyvinyl chloride adhesives, and particularly relates to a high-adhesion polyvinyl chloride adhesive for electronic components and a preparation process thereof. Background Art

[0002] PVC (polyvinyl chloride) is a commonly used resin that is non-flammable, high-strength, corrosion-resistant, and geometrically stable. PVC is highly resistant to common oxidants, reducing agents, strong acids and alkalis, and general organic solvents. PVC resin is one of the three most common synthetic resins currently produced and consumed in China, and is also a popular and widely used polymer synthetic material in the world. Based on its application, PVC can be divided into the following categories: general-purpose, cross-linked, and high-polymerization-degree PVC resins. The general-purpose type is prepared by polymerizing vinyl chloride monomer under the action of an initiator; the high-polymerization type is prepared by adding a chain extender to the vinyl chloride monomer polymerization system to obtain a polymer resin; the cross-linked type is prepared by adding a cross-linking agent containing a diene or polyene to the vinyl chloride monomer polymerization system to produce a polymer resin through a cross-linking reaction. PVC is widely used in electronics, automobiles, aerospace, construction, agriculture, and other fields.

[0003] Since the 1950s, adhesives have been used to encapsulate electronic components, replacing metal, glass, and ceramic materials. This not only reduces component manufacturing costs but also reduces weight and size. PVC adhesives are widely used for encapsulating integrated circuits and electronic components due to their high mechanical properties, low cure shrinkage, and excellent bonding properties. However, with the advancement of technology, electronic products are becoming increasingly miniaturized, portable, highly integrated, and multifunctional. This has led to an increase in heat generation and operating temperatures. Operating temperatures of electronic components can reach 130-150°C. Existing standard PVC adhesives exhibit a rapid decline in bonding performance above 110°C, causing cracking at the bonded areas. Therefore, existing PVC adhesives no longer meet the high-temperature resistance requirements of electronic components, making research on the high-temperature resistance of polyvinyl chloride (PVC) crucial. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the present invention aims to provide a high-adhesion polyvinyl chloride adhesive for electronic components with high temperature resistance and a preparation process thereof. To achieve the above object, the present invention adopts the following technical solutions: A high-adhesion polyvinyl chloride adhesive for electronic components, comprising the following raw materials in parts by weight: 80-100 parts of modified polyvinyl chloride; 10-20 parts of ethylene-vinyl acetate copolymer; 5~10 parts of plasticizer; 60~100 parts of diluent; 5~15 parts of filler; 0.5~3 parts of antioxidant; 0.5~2 parts of anti-ultraviolet agent; The preparation method of the modified polyvinyl chloride is: Add 80-100 parts of polyvinyl chloride resin and 150-200 parts of organic solvent into the reactor, then add 5-10 parts of modifier A , 1 to 5 parts of initiator, heat to 80 to 100°C and stir to react to obtain modified polyvinyl chloride.

[0005] In some embodiments, the plasticizer is selected from one or more of dioctyl phthalate, dioctyl terephthalate, or diisononyl phthalate.

[0006] In some embodiments, the diluent is selected from one or more of tetrahydrofuran, dimethyl sulfoxide, dichloromethane, chloroform, cyclohexanone, acetone, toluene, xylene, n-butyl glycidyl ether, diglycidyl ether, and 1,4-butanediol diglycidyl ether.

[0007] In some embodiments, the antioxidant is selected from one or more of triphenyl phosphite, triphenyl phosphate, antioxidant HP-136, antioxidant 1010, antioxidant 168, antioxidant 1076, and antioxidant 1068.

[0008] In some embodiments, the filler is selected from one or more of calcium carbonate, talc, alumina powder, quartz powder, mica powder, and white carbon black.

[0009] In some embodiments, the anti-ultraviolet agent is selected from one or more of silicon dioxide, calcium oxide, antimony pentoxide, cerium dioxide, yttrium oxide, zinc oxide, nickel oxide, chromium oxide, and titanium dioxide.

[0010] In some embodiments, the initiator is selected from one or more of azobisisoheptanenitrile, dibenzoyl peroxide, and peroxydicarbonate.

[0011] In some embodiments, the organic solvent is selected from one or more of tetrahydrofuran, dimethyl sulfoxide, dichloromethane, chloroform, cyclohexanone, acetone, toluene, and xylene.

[0012] In some embodiments, the mass percentage of vinyl acetate structural units in the ethylene-vinyl acetate copolymer is 15% to 30%.

[0013] The present invention also provides a process for preparing the above-mentioned high-adhesion polyvinyl chloride adhesive for electronic components, comprising the following steps: Step 1: Add a diluent, a plasticizer, and an antioxidant to a reaction container in proportion, stir at 40-60° C. and 200-300 rpm to mix them uniformly, to obtain a mixture A; Step 2: Add modified polyvinyl chloride and ethylene-ethyl acetate copolymer to the mixture A obtained in step 1, and stir at 50-80° C. and 100-200 rpm for 30-60 min to obtain a mixture B; Step 3: Add filler and anti-ultraviolet agent to the mixture B obtained in step 2, and stir at a speed of 100-200 rpm for 30-60 min to mix them evenly to obtain high-adhesion polyvinyl chloride adhesive for electronic components.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1) Modifier A screened by the present invention The novel structure contains long carbon chains that can increase the flexibility of the PVC molecular chain, improve the compatibility of the adhesive with the substrate, promote interfacial contact, and form a physical cross-linking network. Therefore, the obtained polyvinyl chloride adhesive has excellent bonding strength. 2) Modifier A screened by the present invention The imidazole groups contained in the PVC resin have a rigid structure and strong thermal stability. The imidazole cation forms a dipole-ionic bond with the Cl atoms on the PVC chain, which can enhance the interaction between the molecular chains and inhibit the movement of high-temperature segments, thus giving the PVC adhesive excellent high-temperature resistance. DETAILED DESCRIPTION

[0015] The following non-limiting examples are provided to enable those skilled in the art to more fully understand the present invention, but are not intended to limit the present invention in any way. The following are merely illustrative of the scope of the present invention, and those skilled in the art may make various changes and modifications to the present invention based on the disclosed content, which should also fall within the scope of the present invention.

[0016] When numerical ranges are given in the examples, it should be understood that, unless otherwise specified herein, both endpoints of each numerical range and any value between the two endpoints may be selected. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the invention belongs.

[0017] The present invention is further described below by way of specific examples. Unless otherwise specified, the various chemical reagents used in the examples of the present invention were obtained through conventional commercial channels.

[0018] Basic Preparation Example 1 Preparation of Modifier A To a reactor, raw material Compound I (1.0 mol), raw material Compound II (2.1 mol), and anhydrous tetrahydrofuran (500 mL) were added sequentially. After stirring, the mixture was heated to 65°C and stirred for 10 hours. After completion of the reaction, the reaction mixture was cooled to 5°C, whereupon a white solid precipitated. The precipitated solid was then dissolved in dichloromethane (100 mL). Finally, cyclohexane (500 mL) was added to precipitate a white solid. The solid was filtered, and the residue was washed with cyclohexane (3 x 300 mL). The residue was then dried under vacuum at 90°C to obtain Modifier A with a yield of 81.7% and an HPLC purity of 99.3%.

[0019] 1 H-NMR (400 MHz, DMSO- d 6): δ(ppm): 9.01 (s,2H), 7.95(d, 2H), 7.76(d,2H), 5.52 (s,2H), 5.21(t, 4H), 2.10-2.03(m, 4H), 1.34-1.29(m, 12H), 0.86-0.83(m, 6H).

[0020] Basic Preparation Example 2 Preparation of Modified Polyvinyl Chloride 100 parts of polyvinyl chloride resin (PVC-SG5, produced by Xinjiang Tianye Group Co., Ltd.) and 200 parts of toluene were added to a reactor. Then, 10 parts of Modifier A obtained in the Preparation Example and 1 part of dibenzoyl peroxide (initiator) were added and mixed thoroughly. The temperature was raised to 90°C and stirred for 5 hours. After the reaction, the reaction solution was distilled under reduced pressure and dried under vacuum to obtain modified polyvinyl chloride.

[0021] Example 1 A high-adhesion polyvinyl chloride adhesive for electronic components, comprising the following raw materials in parts by weight: 100 parts of modified polyvinyl chloride; 10 parts of ethylene-ethyl acetate copolymer (purchased from Jiangsu Sailbon Petrochemical Co., Ltd., brand UE28400, melt index 400 g / 10 min, VA content 28%); Plasticizer dioctyl phthalate 5 parts; 100 parts of diluent acetone; Filler white carbon black 5 parts; 1 part of antioxidant 1010; 0.5 parts of anti-ultraviolet agent titanium dioxide; The preparation method of the high-adhesion polyvinyl chloride adhesive for electronic components comprises the following steps: Step 1: Add a diluent, a plasticizer, and an antioxidant to a reaction container in proportion, stir at 50° C. and 300 rpm to mix them uniformly, to obtain a mixture A; Step 2: Add modified polyvinyl chloride and ethylene-ethyl acetate copolymer to the mixture A obtained in step 1, and stir at 60° C. and 100 rpm for 30 min to obtain a mixture B; Step 3: Add filler and anti-ultraviolet agent to the mixture B obtained in step 2, and stir at a speed of 100 rpm for 30 minutes to mix them evenly to obtain high-adhesion polyvinyl chloride adhesive for electronic components.

[0022] Example 2 A high-adhesion polyvinyl chloride adhesive for electronic components, comprising the following raw materials in parts by weight: 90 parts of modified polyvinyl chloride; 20 parts of ethylene-ethyl acetate copolymer (purchased from Jiangsu Sailbon Petrochemical Co., Ltd., brand UE28400, melt index 400 g / 10 min, VA content 28%); Plasticizer dioctyl terephthalate 10 parts; 100 parts of diluent toluene; Filler mica powder 10 parts; 1 part of antioxidant 1076; 1 part of anti-ultraviolet agent zinc oxide; The preparation method of the high-adhesion polyvinyl chloride adhesive for electronic components comprises the following steps: Step 1: Add a diluent, a plasticizer, and an antioxidant to a reaction container in proportion, stir at 50° C. and 300 rpm to mix them uniformly, to obtain a mixture A; Step 2: Add modified polyvinyl chloride and ethylene-ethyl acetate copolymer to the mixture A obtained in step 1, and stir at 60° C. and 100 rpm for 30 min to obtain a mixture B; Step 3: Add filler and anti-ultraviolet agent to the mixture B obtained in step 2, and stir at a speed of 100 rpm for 30 minutes to mix them evenly to obtain high-adhesion polyvinyl chloride adhesive for electronic components.

[0023] Example 3 A high-adhesion polyvinyl chloride adhesive for electronic components, comprising the following raw materials in parts by weight: 100 parts of modified polyvinyl chloride; 20 parts of ethylene-ethyl acetate copolymer (purchased from Jiangsu Sailbon Petrochemical Co., Ltd., brand UE28400, melt index 400 g / 10 min, VA content 28%); Plasticizer: dioctyl terephthalate 5 parts; 80 parts of diluent cyclohexanone; Filler calcium carbonate 10 parts; 1 part of antioxidant 1010; 0.5 parts of anti-ultraviolet agent zinc oxide; The preparation method of the high-adhesion polyvinyl chloride adhesive for electronic components comprises the following steps: Step 1: Add a diluent, a plasticizer, and an antioxidant to a reaction container in proportion, stir at 50° C. and 300 rpm to mix them uniformly, to obtain a mixture A; Step 2: Add modified polyvinyl chloride and ethylene-ethyl acetate copolymer to the mixture A obtained in step 1, and stir at 60° C. and 100 rpm for 30 min to obtain a mixture B; Step 3: Add filler and anti-ultraviolet agent to the mixture B obtained in step 2, and stir at a speed of 100 rpm for 30 minutes to mix them evenly to obtain high-adhesion polyvinyl chloride adhesive for electronic components.

[0024] Comparative Example 1 On the basis of Example 1, the modified polyvinyl chloride was replaced by unmodified polyvinyl chloride, and the other operations and steps were the same as those in Example 1.

[0025] Comparative Example 2 On the basis of basic preparation example 2, modifier A Replaced with Modifier B , other operations and steps are the same as those in Basic Preparation Example 2 to obtain modified polyvinyl chloride.

[0026] On the basis of Example 1, the modified polyvinyl chloride is replaced by the polyvinyl chloride modified with the above-mentioned modifier B, and the other operations and steps are the same as Example 1.

[0027] Performance Testing The mechanical properties and flame retardant properties of the high-adhesion polyvinyl chloride adhesives for electronic components obtained in Examples 1-3 and Comparative Examples 1-2 were tested using the following test methods: Bond shear strength: PVC adhesive was applied to the bonded test piece to form a uniform film with a thickness of 0.2 mm. After curing, the shear strength was measured at room temperature (23°C) using GB / T 7124-2008. Curing was performed using an IGE XC210 UV lamp (wavelength 365 nm) with a light intensity of 1000 mw / cm 2 , time is 30 seconds; then dried at 80℃ for 2h.

[0028] High temperature resistance: heat treat the cured polyvinyl chloride adhesive in a blast drying oven at 200°C for 30 minutes, and then test the bonding shear strength again after cooling. Calculate the bonding shear strength retention rate in %.

[0029] Double 85 test: Test conditions: 85°C / 85% RH, 500h, test bond shear strength retention rate, unit: %. Results are shown in Table 1.

[0030] Table 1 Performance test results From the data of Example 1 and Comparative Examples 1-2 in Table 1, it can be seen that the use of modifier A The obtained polyvinyl chloride adhesive has better bonding strength and high temperature and high humidity resistance.

[0031] The main reasons for the aforementioned properties of the polyvinyl chloride adhesive of the present invention are: 1) Modifier A, screened and obtained in this application, has a novel structure. Its long carbon chain increases the flexibility of the PVC molecular chain, improves the compatibility of the adhesive with the substrate, promotes interfacial contact, and forms a physical crosslinking network, thereby achieving stronger bond strength; 2) The imidazole groups contained in Modifier A have a rigid structure and possess strong thermal stability. Furthermore, the imidazole cations form dipole-ionic bonds with the Cl atoms on the PVC chain, enhancing the intermolecular chain forces and inhibiting the movement of high-temperature chain segments, thereby endowing the polyvinyl chloride adhesive with excellent high-temperature resistance.

[0032] The above embodiments are preferred implementations of the present invention, but the implementations of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be considered equivalent replacement methods and are included in the scope of protection of the present invention.

Claims

1. A high-adhesion polyvinyl chloride adhesive for electronic components, characterized in that: Calculated by weight, it includes the following raw materials: 80-100 parts of modified polyvinyl chloride; 10-20 parts of ethylene-vinyl acetate copolymer; 5~10 parts of plasticizer; 60~100 parts of diluent; 5~15 parts of filler; 0.5~3 parts of antioxidant; 0.5~2 parts of anti-ultraviolet agent; The preparation method of the modified polyvinyl chloride is: Add 80-100 parts of polyvinyl chloride resin and 150-200 parts of organic solvent into the reactor, then add 5-10 parts of modifier A , 1 to 5 parts of initiator, heat to 80 to 100°C and stir to react to obtain modified polyvinyl chloride.

2. The high-adhesion polyvinyl chloride adhesive for electronic components according to claim 1, characterized in that: The plasticizer is selected from one or more of dioctyl phthalate, dioctyl terephthalate or diisononyl phthalate.

3. The high-adhesion polyvinyl chloride adhesive for electronic components according to claim 1, characterized in that: The diluent is selected from one or more of tetrahydrofuran, dimethyl sulfoxide, dichloromethane, chloroform, cyclohexanone, acetone, toluene, xylene, n-butyl glycidyl ether, diglycidyl ether, and 1,4-butanediol diglycidyl ether.

4. The high-adhesion polyvinyl chloride adhesive for electronic components according to claim 1, characterized in that: The antioxidant is selected from one or more of triphenyl phosphite, triphenyl phosphate, antioxidant HP-136, antioxidant 1010, antioxidant 168, antioxidant 1076, and antioxidant 1068.

5. The high-adhesion polyvinyl chloride adhesive for electronic components according to claim 1, characterized in that: The filler is selected from one or more of calcium carbonate, talc powder, alumina powder, quartz powder, mica powder, and white carbon black.

6. The high-adhesion polyvinyl chloride adhesive for electronic components according to claim 1, characterized in that: The anti-ultraviolet agent is selected from one or more of silicon dioxide, calcium oxide, antimony pentoxide, cerium dioxide, yttrium oxide, zinc oxide, nickel oxide, chromium oxide, and titanium dioxide.

7. The high-adhesion polyvinyl chloride adhesive for electronic components according to claim 1, characterized in that: The initiator is selected from one or more of azobisisoheptanenitrile, dibenzoyl peroxide, and peroxydicarbonate.

8. The high-adhesion polyvinyl chloride adhesive for electronic components according to claim 1, characterized in that: The organic solvent is selected from one or more of tetrahydrofuran, dimethyl sulfoxide, dichloromethane, chloroform, cyclohexanone, acetone, toluene, and xylene.

9. The high-adhesion polyvinyl chloride adhesive for electronic components according to claim 1, characterized in that: The mass percentage of the vinyl acetate structural unit in the ethylene-vinyl acetate copolymer is 15% to 30%.

10. A process for preparing the high-adhesion polyvinyl chloride adhesive for electronic components according to any one of claims 1 to 9, comprising the following steps: Step 1: Add a diluent, a plasticizer, and an antioxidant to a reaction container in proportion, stir at 40-60° C. and 200-300 rpm to mix them uniformly, to obtain a mixture A; Step 2: Add modified polyvinyl chloride and ethylene-ethyl acetate copolymer to the mixture A obtained in step 1, and stir at 50-80° C. and 100-200 rpm for 30-60 min to obtain a mixture B; Step 3: Add filler and anti-ultraviolet agent to the mixture B obtained in step 2, and stir at a speed of 100-200 rpm for 30-60 min to mix them evenly to obtain high-adhesion polyvinyl chloride adhesive for electronic components.

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