Electronic glue containing normal hexane and preparation method thereof

Abstract

The present invention relates to the technical field of electronic glue, and discloses an electronic glue containing n-hexane and a preparation method thereof, wherein n-hexane, sulfur-modified polyurethane, epoxidized benzoxazine, defoamer BYKA555, and dispersant AA-75 are added to a reactor, stirred evenly, vacuum degassing, injection molding, and solidified to obtain an electronic glue containing n-hexane. During stirring, the terminal hydroxyl group in the sulfur-modified polyurethane will undergo a ring-opening reaction with the epoxy group in the epoxidized benzoxazine, and cross-linking will be generated between each other, so that it is more closely connected, and the tensile properties of the electronic glue are improved; and the bismaleimide resin therein itself has a good stretching effect. The sulfur element and nitrogen element in the sulfur-modified polyurethane and the epoxidized benzoxazine have a good flame retardant effect, which improves the flame retardant properties of the electronic glue, and the benzoxazine therein will form a heat-resistant phenolic resin structure at high temperature, so that it has a good flame retardant effect.

Description

Technical Field

[0001] The invention relates to the technical field of electronic glue, in particular to an electronic glue containing n-hexane and a preparation method thereof. Background Art

[0002] Electronic glue is a special adhesive used for bonding, sealing, potting and coating electronic and electrical components. The use of electronic glue can play a role in moisture-proof, dust-proof, and corrosion-proof, but if it encounters a fire during use, its flammability will affect its normal use; it is easy to deform and tear when subjected to external force, which will also affect its normal use; therefore, how to avoid this phenomenon is the key to solving the problem. For example, patent CN110256992A discloses a high-performance electronic glue. The electronic glue of this invention has high temperature resistance and can emit strong fluorescence under ultraviolet light excitation. It has certain anti-counterfeiting properties, but its flame retardant effect has not been improved. Summary of the invention

[0003] 1. Technical issues to be resolved

[0004] In view of the deficiencies in the prior art, the present invention provides an electronic adhesive containing n-hexane and a preparation method thereof, which has good flame retardant and stretching effects.

[0005] (II) Technical solution

[0006] To achieve the above-mentioned purpose, the present invention provides the following technical scheme: an electronic glue containing n-hexane, comprising the following weight components: 0.1-0.3 weight parts of n-hexane, 3-5 weight parts of sulfur-modified polyurethane, 4-7 weight parts of epoxidized benzoxazine, 0.4-0.6 weight parts of defoamer BYKA555, and 1-1.2 weight parts of dispersant AA-75.

[0007] Preferably, the preparation method of the sulfur-modified polyurethane is:

[0008] (1) Add bismaleimide resin and diallyl bisphenol A into a reactor, stir and mix, heat to 110-130° C., stir and react for 12-16 minutes, and then cool to room temperature to obtain intermediate 1;

[0009] (2) adding intermediate 1 to N,N-dimethylformamide solvent, stirring and dispersing, then adding 2-aminoethanethiol and benzoin dimethyl ether photoinitiator, irradiating with 365 nm ultraviolet light at 30-45° C. for 3-5 h, centrifuging, washing and drying to obtain amino-modified maleimide resin;

[0010] (3) adding 4-7 parts by weight of an amino-modified maleimide resin and 2-3 parts by weight of 2,2-bis(bromomethyl)-1,3-propylene glycol to an acetone solvent, stirring to dissolve, and then adding a sodium hydroxide aqueous solution having a molar concentration of 4-6 mol / L to the mixture, reacting at 60-80° C., and after reaction, adding dilute hydrochloric acid dropwise to neutralize the mixture, concentrating to remove the solvent, filtering, washing and drying to obtain a sulfur-containing chain extender;

[0011] (4) After removing water from the polyether diol, mix it evenly with hexamethylene diisocyanate, introduce nitrogen, then add dibutyltin dilaurate as a catalyst dropwise, react at 65-80°C for 2-5 hours to carry out prepolymerization, then add a sulfur-containing chain extender, stir to continue the chain extension reaction, react at 50-70°C for 4-6 hours, and after the reaction is completed, cool and discharge to obtain a sulfur-modified polyurethane.

[0012] Preferably, the mass ratio of bismaleimide resin to diallyl bisphenol A in (1) is 1:1.1-1.3.

[0013] Preferably, the mass ratio of the intermediate 1, 2-aminoethanethiol, and benzoin dimethyl ether photoinitiator in (2) is 0.8-1.2:1:0.02-0.03.

[0014] Preferably, the reaction time in (3) is 7-9 hours.

[0015] Preferably, the mass ratio of the polyether diol, hexamethylene diisocyanate, dibutyltin dilaurate catalyst, and sulfur-containing chain extender in (4) is 1.2-2:1:0.01-0.02:0.6-0.8.

[0016] Preferably, the preparation method of the epoxidized benzoxazine is:

[0017] S1. 8-10 parts by weight of intermediate 1, 14-20 parts by weight of an aqueous solution of formaldehyde, and 12-15 parts by weight of phenol are added to a toluene solvent and fully dissolved, and a cyclization reaction is carried out at 70-90° C. for 10-14 hours. After completion, the reaction is distilled under reduced pressure, washed with deionized water, and the crude product is recrystallized from dichloromethane to obtain an olefinated benzoxazine;

[0018] S2. Add 3-5 parts by weight of olefinated benzoxazine to N,N-dimethylformamide solvent, stir evenly, then add 10-16 parts by weight of aqueous hydrogen peroxide solution, react at 30-40° C. for 3-7 hours, and then distill under reduced pressure, filter and dry to obtain epoxidized benzoxazine.

[0019] Preferably, the preparation method of the electronic glue containing n-hexane is: add n-hexane, sulfur-modified polyurethane, epoxidized benzoxazine, defoamer BYKA555, and dispersant AA-75 into a reactor, stir evenly at a stirring temperature of 115-120°C, stir for 3-5 hours, vacuum degassing, injection molding, and curing to obtain the electronic glue containing n-hexane.

[0020] 3. Beneficial technical effects

[0021] The invention prepares electronic glue containing n-hexane by adding n-hexane, sulfur-modified polyurethane, epoxidized benzoxazine, defoamer BYKA555 and dispersant AA-75 into a reactor, stirring evenly, vacuum degassing, injection molding and curing.

[0022] During the stirring process, the terminal hydroxyl groups in the sulfur-modified polyurethane will undergo a ring-opening reaction with the epoxy groups in the epoxidized benzoxazine, resulting in cross-linking between them, making the connection tighter and improving the tensile properties of the electronic glue; and the bismaleimide resin itself has a good tensile effect. The sulfur and nitrogen elements in the sulfur-modified polyurethane and epoxidized benzoxazine have a good flame retardant effect, which improves the flame retardant properties of the electronic glue. The benzoxazine will form a heat-resistant phenolic resin structure at high temperature, giving it a good flame retardant effect; a small amount of n-hexane can also adjust the viscosity and drying speed of the glue. DETAILED DESCRIPTION Example 1

[0023] (1) adding bismaleimide resin and diallyl bisphenol A into a reactor, wherein the mass ratio of bismaleimide resin to diallyl bisphenol A is 1:1.1, stirring and mixing, heating to 110° C. and stirring for 12 min, and then cooling to room temperature to obtain intermediate 1;

[0024] (2) adding intermediate 1 to N,N-dimethylformamide solvent, stirring and dispersing, and then adding 2-aminoethanethiol and benzoin dimethyl ether photoinitiator, wherein the mass ratio of intermediate 1, 2-aminoethanethiol, and benzoin dimethyl ether photoinitiator is 0.8:1:0.02, irradiating with 365 nm ultraviolet light at 30° C. for 3 h, centrifuging after irradiation, washing and drying to obtain amino-modified maleimide resin;

[0025] (3) Add 4 parts by weight of amino-modified maleimide resin and 2 parts by weight of 2,2-bis(bromomethyl)-1,3-propylene glycol to an acetone solvent, stir to dissolve, then continue to add a 4 mol / L sodium hydroxide aqueous solution, react at 60° C. for 7 h, and then dropwise add dilute hydrochloric acid to neutralize, concentrate to remove the solvent, filter, wash and dry to obtain a sulfur-containing chain extender;

[0026] (4) After removing water from the polyether diol, mix it evenly with hexamethylene diisocyanate, introduce nitrogen, then drop a dibutyltin dilaurate catalyst, react at 65°C for 2 hours, perform prepolymerization, then add a sulfur-containing chain extender, wherein the mass ratio of polyether diol, hexamethylene diisocyanate, dibutyltin dilaurate catalyst, and sulfur-containing chain extender is 1.2:1:0.01:0.6, stir to continue the chain extension reaction, react at 50°C for 4 hours, and after the reaction is completed, cool and discharge to obtain a sulfur-modified polyurethane;

[0027] (5) 8 parts by weight of the intermediate 1, 14 parts by weight of an aqueous solution of formaldehyde, and 12 parts by weight of phenol were added to a toluene solvent and fully dissolved, and a cyclization reaction was carried out at 70° C. for 10 hours. After the reaction, the mixture was distilled under reduced pressure, washed with deionized water, and the crude product was recrystallized from dichloromethane to obtain an olefinated benzoxazine;

[0028] (6) Add 3 parts by weight of olefinated benzoxazine to N,N-dimethylformamide solvent, stir evenly, then add 10 parts by weight of hydrogen peroxide aqueous solution, react at 30° C. for 3 h, and then distill under reduced pressure, filter and dry to obtain epoxidized benzoxazine;

[0029] (7) Add 0.1 parts by weight of n-hexane, 3 parts by weight of sulfur-modified polyurethane, 4 parts by weight of epoxidized benzoxazine, 0.4 parts by weight of defoamer BYKA555, and 1 part by weight of dispersant AA-75 into the reactor, stir evenly at a stirring temperature of 115°C for 3 hours, vacuum degassing, injection molding, and curing to obtain an electronic glue containing n-hexane. Example 2

[0030] (1) adding bismaleimide resin and diallyl bisphenol A into a reactor, wherein the mass ratio of bismaleimide resin to diallyl bisphenol A is 1:1.3, stirring and mixing, heating to 130° C. and stirring for 16 min, and then cooling to room temperature to obtain intermediate 1;

[0031] (2) adding intermediate 1 to N,N-dimethylformamide solvent, stirring and dispersing, and then adding 2-aminoethanethiol and benzoin dimethyl ether photoinitiator, wherein the mass ratio of intermediate 1, 2-aminoethanethiol, and benzoin dimethyl ether photoinitiator is 1.2:1:0.03, irradiating with 365 nm ultraviolet light at 45°C for 5 h, centrifuging after irradiation, washing and drying to obtain amino-modified maleimide resin;

[0032] (3) Add 7 parts by weight of amino-modified maleimide resin and 3 parts by weight of 2,2-bis(bromomethyl)-1,3-propylene glycol to an acetone solvent, stir to dissolve, then continue to add a 6 mol / L sodium hydroxide aqueous solution, react at 80° C. for 9 h, and then dropwise add dilute hydrochloric acid to neutralize, concentrate to remove the solvent, filter, wash and dry to obtain a sulfur-containing chain extender;

[0033] (4) After removing water from the polyether diol, mix it evenly with hexamethylene diisocyanate, introduce nitrogen, then drop a dibutyltin dilaurate catalyst, react at 80°C for 5 hours, perform prepolymerization, then add a sulfur-containing chain extender, wherein the mass ratio of polyether diol, hexamethylene diisocyanate, dibutyltin dilaurate catalyst, and sulfur-containing chain extender is 2:1:0.02:0.8, stir to continue the chain extension reaction, react at 70°C for 6 hours, and after the reaction is completed, cool and discharge to obtain a sulfur-modified polyurethane;

[0034] (5) 10 parts by weight of the intermediate 1, 20 parts by weight of an aqueous solution of formaldehyde, and 15 parts by weight of phenol were added to a toluene solvent and fully dissolved, and a cyclization reaction was carried out at 90° C. for 14 h. After the reaction, the mixture was distilled under reduced pressure, washed with deionized water, and the crude product was recrystallized from dichloromethane to obtain an olefinated benzoxazine;

[0035] (6) Add 5 parts by weight of olefinated benzoxazine to N,N-dimethylformamide solvent, stir evenly, then add 16 parts by weight of hydrogen peroxide aqueous solution, react at 40° C. for 7 hours, and then distill under reduced pressure, filter and dry to obtain epoxidized benzoxazine;

[0036] (7) Add 0.3 parts by weight of n-hexane, 5 parts by weight of sulfur-modified polyurethane, 7 parts by weight of epoxidized benzoxazine, 0.6 parts by weight of defoamer BYKA555, and 1.2 parts by weight of dispersant AA-75 into a reactor, stir evenly at a stirring temperature of 120°C for 5 hours, vacuum degassing, injection molding, and curing to obtain an electronic glue containing n-hexane. Example 3

[0037] (1) adding bismaleimide resin and diallyl bisphenol A into a reactor, wherein the mass ratio of bismaleimide resin to diallyl bisphenol A is 1:1.2, stirring and mixing, heating to 120° C. and stirring for 14 min, and then cooling to room temperature to obtain intermediate 1;

[0038] (2) adding intermediate 1 to N,N-dimethylformamide solvent, stirring and dispersing, and then adding 2-aminoethanethiol and benzoin dimethyl ether photoinitiator, wherein the mass ratio of intermediate 1, 2-aminoethanethiol, and benzoin dimethyl ether photoinitiator is 1.0:1:0.025, irradiating with 365 nm ultraviolet light at 40° C. for 4 h, centrifuging after irradiation, washing and drying to obtain amino-modified maleimide resin;

[0039] (3) Add 5 parts by weight of amino-modified maleimide resin and 2.5 parts by weight of 2,2-bis(bromomethyl)-1,3-propylene glycol to an acetone solvent, stir to dissolve, then continue to add a 5 mol / L sodium hydroxide aqueous solution, react at 70° C. for 8 h, and then dropwise add dilute hydrochloric acid to neutralize, concentrate to remove the solvent, filter, wash and dry to obtain a sulfur-containing chain extender;

[0040] (4) After removing water from the polyether diol, mix it evenly with hexamethylene diisocyanate, introduce nitrogen, then drop dibutyltin dilaurate catalyst, react at 72°C for 3 hours to perform prepolymerization, then add sulfur-containing chain extender, wherein the mass ratio of polyether diol, hexamethylene diisocyanate, dibutyltin dilaurate catalyst, and sulfur-containing chain extender is 1.6:1:0.015:0.7, stir to continue chain extension reaction, react at 60°C for 5 hours, and after the reaction is completed, cool and discharge to obtain sulfur-modified polyurethane;

[0041] (5) 9 parts by weight of the intermediate 1, 17 parts by weight of an aqueous solution of formaldehyde, and 14 parts by weight of phenol were added to a toluene solvent and fully dissolved, and a cyclization reaction was carried out at 80° C. for 12 h. After the reaction, the mixture was distilled under reduced pressure, washed with deionized water, and the crude product was recrystallized from dichloromethane to obtain an olefinated benzoxazine;

[0042] (6) adding 4 parts by weight of olefinated benzoxazine to N,N-dimethylformamide solvent, stirring evenly, adding 13 parts by weight of aqueous hydrogen peroxide solution thereto, reacting at 35° C. for 5 h, and then distilling under reduced pressure, filtering and drying to obtain epoxidized benzoxazine;

[0043] (7) Add 0.2 parts by weight of n-hexane, 4 parts by weight of sulfur-modified polyurethane, 5.5 parts by weight of epoxidized benzoxazine, 0.5 parts by weight of defoamer BYKA555, and 1.1 parts by weight of dispersant AA-75 into the reactor, stir evenly at a stirring temperature of 118°C for 4 hours, vacuum degassing, injection molding, and curing to obtain an electronic glue containing n-hexane.

[0044] Comparative Example 1

[0045] 0.2 parts by weight of n-hexane, 5.5 parts by weight of epoxidized benzoxazine, 0.5 parts by weight of defoamer BYKA555, and 1.1 parts by weight of dispersant AA-75 were added to the reactor and stirred evenly at a stirring temperature of 118°C for 4 hours, vacuum degassing, injection molding, and curing to obtain an electronic glue containing n-hexane.

[0046] Comparative Example 2

[0047] Add 0.2 parts by weight of n-hexane, 4 parts by weight of sulfur-modified polyurethane, 0.5 parts by weight of defoamer BYKA555, and 1.1 parts by weight of dispersant AA-75 into the reactor, stir evenly at a stirring temperature of 118°C for 4 hours, vacuum degassing, injection molding, and curing to obtain electronic glue containing n-hexane.

[0048] Use an oxygen index meter to test the limiting oxygen index of electronic glue; use a horizontal and vertical combustion instrument to test the combustion level of electronic glue.

[0049] Table 1: Flame retardancy tests.

[0050] project Limiting oxygen index (%) Combustion level Example 1 32 V-0 Example 2 33 V-0 Example 3 32 V-0 Comparative Example 1 20 V-1 Comparative Example 2 21 V-1

[0051] It can be seen from Table 1 that the flame retardant effect of Examples 1-3 is better than that of Comparative Examples 1-2, which indicates that the electronic adhesive prepared by the present invention has good flame retardant effect.

[0052] The mechanical properties of the electronic adhesive were tested using a universal electronic testing machine with a tensile rate of 100 mm / min.

[0053] Table 2: Tensile strength test.

[0054] project Tensile strength (MPa) Example 1 27.34 Example 2 28.79 Example 3 27.36 Comparative Example 1 21.46 Comparative Example 2 20.31

[0055] It can be seen from Table 2 that the electronic adhesive prepared by the present invention has good tensile strength.

[0056] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. An electronic glue containing n-hexane, characterized in that: The invention comprises the following components by weight: 0.1-0.3 parts by weight of n-hexane, 3-5 parts by weight of sulfur-modified polyurethane, 4-7 parts by weight of epoxidized benzoxazine, 0.4-0.6 parts by weight of defoamer BYKA555, and 1-1.2 parts by weight of dispersant AA-75; The preparation method of the sulfur-modified polyurethane is: (1) Add bismaleimide resin and diallyl bisphenol A into a reactor, stir and mix, heat to 110-130° C., stir and react for 12-16 minutes, and then cool to room temperature to obtain intermediate 1; (2) adding intermediate 1 to N,N-dimethylformamide solvent, stirring and dispersing, then adding 2-aminoethanethiol and benzoin dimethyl ether photoinitiator, irradiating with 365 nm ultraviolet light at 30-45° C. for 3-5 h, centrifuging, washing and drying to obtain amino-modified maleimide resin; (3) adding 4-7 parts by weight of an amino-modified maleimide resin and 2-3 parts by weight of 2,2-bis(bromomethyl)-1,3-propylene glycol to an acetone solvent, stirring to dissolve, and then adding a sodium hydroxide aqueous solution having a molar concentration of 4-6 mol / L to the mixture, reacting at 60-80° C., and after reaction, adding dilute hydrochloric acid dropwise to neutralize the mixture, concentrating to remove the solvent, filtering, washing and drying to obtain a sulfur-containing chain extender; (4) After removing water from the polyether diol, mix it evenly with hexamethylene diisocyanate, introduce nitrogen, then drop dibutyltin dilaurate as a catalyst, react at 65-80°C for 2-5h to perform prepolymerization, then add a sulfur-containing chain extender, stir to continue the chain extension reaction, react at 50-70°C for 4-6h, and after the reaction is completed, cool and discharge to obtain a sulfur-modified polyurethane; The mass ratio of bismaleimide resin to diallyl bisphenol A in (1) is 1:1.1-1.3; The mass ratio of the intermediate 1, 2-aminoethanethiol and benzoin dimethyl ether photoinitiator in (2) is 0.8-1.2:1:0.02-0.03; The reaction time in (3) is 7-9h; The mass ratio of the polyether diol, hexamethylene diisocyanate, dibutyltin dilaurate catalyst, and sulfur-containing chain extender in (4) is 1.2-2:1:0.01-0.02:0.6-0.8; The preparation method of the epoxidized benzoxazine is: S1. 8-10 parts by weight of intermediate 1, 14-20 parts by weight of an aqueous solution of formaldehyde, and 12-15 parts by weight of phenol are added to a toluene solvent and fully dissolved, and a cyclization reaction is carried out at 70-90° C. for 10-14 hours. After completion, the reaction is distilled under reduced pressure, washed with deionized water, and the crude product is recrystallized from dichloromethane to obtain an olefinated benzoxazine; S2. Add 3-5 parts by weight of olefinated benzoxazine to N,N-dimethylformamide solvent, stir evenly, then add 10-16 parts by weight of aqueous hydrogen peroxide solution, react at 30-40° C. for 3-7 hours, and then distill under reduced pressure, filter and dry to obtain epoxidized benzoxazine.

2. A method for preparing an electronic glue containing n-hexane as claimed in claim 1, characterized in that: The preparation method of the electronic glue containing n-hexane is as follows: n-hexane, sulfur-modified polyurethane, epoxidized benzoxazine, defoamer BYKA555, and dispersant AA-75 are added to a reactor, stirred evenly at a stirring temperature of 115-120° C., stirred for 3-5 hours, vacuum degassing, injection molding, and curing to obtain the electronic glue containing n-hexane.