阅读说明：本技术 一种含硫含芴结构高折射率光学树脂的制备方法 (Preparation method of sulfur-containing fluorene-containing structure high-refractive-index optical resin ) 是由 姚伯龙 倪亚洲 程广鸿 王宇通 陈欢 张晋瑞 王海潮 王利魁 于 2020-12-23 设计创作，主要内容包括：一种含硫含芴结构高折射率光学树脂的制备方法,属于光学材料技术领域。本发明首先将9,9-二[(2,3-环氧丙氧基)苯基]芴和4’4-二巯基二苯硫醚在催化剂的作用下,室温通过环氧硫“点击”反应进行聚合,合成一种高折光率的环氧树脂；然后通过邻二氯苄和硫脲反应制备出拥有高折光率的1,2-苯二甲硫醇,用作环氧树脂的固化剂；最后通过热固化的方法制备出含硫含芴结构的高折射率光学树脂。本发明通过简单高效的反应,制备得到一种含硫含芴结构的高折光光学树脂,该树脂具有很好的光学性能,高折光率,高透光率,有很好的耐热性能,很好的附着力和机械性能。该树脂在发光二极管封装材料、减反射涂层、光学镜片、光学元件粘合剂等有很好的应用前景。(A preparation method of sulfur-containing fluorene-containing high-refractive-index optical resin belongs to the technical field of optical materials. Firstly, polymerizing 9, 9-bis [ (2, 3-epoxypropoxy) phenyl ] fluorene and 4', 4-dimercaptodiphenyl sulfide at room temperature under the action of a catalyst through epoxy sulfur click reaction to synthesize epoxy resin with high refractive index; then 1, 2-benzenedimethylmercaptan with high refractive index is prepared by the reaction of o-dichlorobenzyl and thiourea and is used as a curing agent of epoxy resin; finally, the optical resin with high refractive index containing sulfur and fluorene structure is prepared by a thermal curing method. The high-refractive-index optical resin containing the sulfur and the fluorene structure is prepared through simple and efficient reaction, and has good optical performance, high refractive index, high light transmittance, good heat resistance, good adhesive force and good mechanical property. The resin has good application prospect in LED packaging materials, antireflection coatings, optical lenses, optical element adhesives and the like.)

1. A preparation method of sulfur-containing fluorene-containing high-refractive-index optical resin is characterized by comprising the following steps: firstly, polymerizing 9, 9-bis [ (2, 3-epoxypropoxy) phenyl ] fluorene and 4', 4-dimercaptodiphenyl sulfide at room temperature under the action of a catalyst through epoxy sulfur click reaction to synthesize the epoxy resin with high refractive index; then 1, 2-benzenedimethylmercaptan with high refractive index is prepared by the reaction of o-dichlorobenzyl and thiourea and is used as a curing agent of epoxy resin; finally, the optical resin with high refractive index containing sulfur and fluorene structure is prepared by a thermal curing method.

2. The method for preparing the sulfur-containing fluorene-containing structure high refractive index optical resin according to claim 1, comprising the steps of:

(1) synthesis of epoxy resin: respectively dissolving 9, 9-bis [ (2, 3-epoxypropoxy) phenyl ] fluorene and 4', 4-dimercaptodiphenyl sulfide in a solvent A; firstly, putting dissolved 9, 9-bis [ (2, 3-epoxypropoxy) phenyl ] fluorene into a reaction container, then adding a catalyst, then dropwise adding a 4', 4-dimercaptodiphenyl sulfide solution, continuing to react after the dropwise adding is finished, cooling to room temperature, carrying out reduced pressure distillation to remove impurities, and finally determining the epoxy value of the resin by a hydrochloric acid-acetone method;

(2) and (3) synthesis of a curing agent: dissolving o-dichlorobenzyl and thiourea in a solvent B, placing the solution in a reaction vessel, refluxing, filtering, and washing with a solvent C to obtain a white solid; dissolving the white solid in distilled water, beginning to dropwise add NaOH solution, refluxing, adjusting the pH value by using a neutralizing agent, extracting by using an extracting agent, drying, and finally carrying out reduced pressure distillation to obtain a curing agent 1, 2-benzenedimethylmercaptan;

(3) curing of the epoxy resin: adding the curing agent prepared in the step (2) into the epoxy resin solution prepared in the step (1) to obtain a dispersion liquid; and (3) spin-coating the dispersion liquid, and curing in a drying oven to obtain the sulfur-containing fluorene-containing high-refractive-index optical resin.

3. The method for preparing the sulfur-containing fluorene-containing structure-high refractive index optical resin according to claim 2, wherein: in the step (1), the solvent A is N, N-dimethylacetamide (DMAc); the catalyst is a saturated methanol solution of LiOH.

4. The method for preparing the sulfur-containing fluorene-containing structure-high refractive index optical resin according to claim 2, wherein: in the step (2), the solvent B is ethanol; the solvent C is a mixed solution of ethanol and diethyl ether; the neutralizer is concentrated sulfuric acid; the extractant is dichloromethane or ethyl acetate.

5. The method for preparing the sulfur-containing fluorene-containing structure-high refractive index optical resin according to claim 2, wherein: the impurity in the step (1) is specifically methanol.

6. The method for preparing the sulfur-containing fluorene-containing structure high refractive index optical resin according to claim 2, wherein the step (1) is specifically: dissolving 9.25-13.875g of 9, 9-bis [ (2, 3-epoxypropoxy) phenyl ] fluorene in 20-30mL of solvent A, and dissolving 12.5-18.75g of 4' 4-dimercaptodiphenyl sulfide in 10-15mL of solvent A; firstly, putting a 9, 9-bis [ (2, 3-epoxypropoxy) phenyl ] fluorene solution into a 250mL three-neck flask, then adding 3-4 drops of catalyst, then beginning to dropwise add the prepared 4' 4-dimercaptodiphenyl sulfide solution for 15-25min, and continuing to react for 0.5-1.5h after dropwise adding is finished; and after the reaction is cooled to room temperature, carrying out reduced pressure distillation at-0.1-0 MPa and 40-45 ℃ for 1-1.5h to remove impurities, and finally determining the epoxy value of the resin by a hydrochloric acid-acetone method.

7. The method for preparing the sulfur-containing fluorene-containing structure high refractive index optical resin according to claim 2, wherein the step (2) is specifically: dissolving 9.98-14.97g of o-dichlorobenzyl and 8.68-13.02g of thiourea in 160mL of solvent B, placing the solution in a 250mL three-neck flask, and stirring and refluxing for 30-45 min; filtering, and washing with a solvent C to obtain a white solid; completely dissolving 9-10g of white solid in 100-150mL of distilled water, placing the solution in a 250mL three-neck flask, dropwise adding 42-50g of NaOH solution with the mass concentration of 15% -18%, refluxing for 3h, adjusting the pH value to 7-7.5 by using a neutralizing agent, and extracting by using an extracting agent; drying, and finally carrying out reduced pressure distillation at-0.1-0 MPa and 30-35 ℃ for 1-1.5h to obtain the product, namely the curing agent 1, 2-benzenedimethylmercaptan.

8. The method for preparing the sulfur-containing fluorene-containing structure high refractive index optical resin according to claim 2, wherein the step (3) is specifically: adding the curing agent prepared in the step (2) into the epoxy resin solution prepared in the step (1) to obtain a dispersion liquid; wherein n (epoxy group): n (-SH) is 1: 0.8; spin-coating the dispersion liquid on a glass plate or a silicon wafer for 30-35s at the speed of 1800 plus 2000r/min by using a desktop spin coater, placing the glass plate or the silicon wafer in an oven for curing for 4-6h at the temperature of 100 plus 150 ℃, and finally preparing the fluorine-containing structure-containing optical resin with high refractive index.

9. The method for producing a sulfur-containing fluorene-containing structure-high refractive index optical resin according to claim 8, wherein in the step (3): and respectively dripping the dispersion liquid on a glass slide and a silicon chip, and spin-coating by adopting a self-leveling mode or a desk-top spin coater.

10. The method for producing a sulfur-containing fluorene-containing structure-high refractive index optical resin according to claim 8, wherein in the step (3): and during curing, the material is placed in an oven at 100 ℃ for curing for 1h, then the temperature is raised to 120 ℃ for curing for 2h, and finally the temperature is raised to 150 ℃ for curing for 2h, so that the sulfur-containing fluorene-containing high-refractive-index optical resin is obtained.

Technical Field

The invention relates to a preparation method of sulfur-containing fluorene-containing high-refractive-index optical resin, belonging to the technical field of optical materials.

Background

The high-refractive-index optical resin has the advantages of light weight, adjustable structure and performance, optical transparency, impact resistance, easiness in processing and forming and low cost, and is widely applied to the fields of optical components such as sensors, detectors, light-emitting diodes, micro-lens arrays, optical fibers and the like.

The sulfur atom-containing polymer has the advantages of low relative density of sulfur atoms, small dispersion, high molar refractive index, good environmental stability, no toxicity, excellent electrical property, optical property, good adhesion to base materials, good heat resistance and the like. The fluorene structure has very high molar refractive index, and the introduction of the fluorene structure into the resin can reduce the crosslinking density of the resin after curing, improve the rigidity of the molecular chain and increase the glass transition temperature of the resin. The sulfur element and the fluorene structure are simultaneously introduced into the polymer resin, which is a very effective way for preparing high-performance optical materials.

Disclosure of Invention

The invention aims to overcome the defects and provide the preparation method of the sulfur-containing fluorene-containing high-refractive-index optical resin, which has good optical performance, high refractive index, high light transmittance, good heat resistance, good adhesive force and good mechanical property.

The technical scheme of the invention is that a preparation method of optical resin containing sulfur, fluorine and high refractive index comprises the steps of firstly polymerizing 9, 9-bis [ (2, 3-epoxypropoxy) phenyl ] fluorene and 4', 4-dimercapto diphenyl sulfide at room temperature under the action of a catalyst through epoxy sulfur click reaction to synthesize epoxy resin with high refractive index; then 1, 2-benzenedimethylmercaptan with high refractive index is prepared by the reaction of o-dichlorobenzyl and thiourea and is used as a curing agent of epoxy resin; finally, the optical resin with high refractive index containing sulfur and fluorene structure is prepared by a thermal curing method.

Further, the steps are as follows:

(1) synthesis of epoxy resin: respectively dissolving 9, 9-bis [ (2, 3-epoxypropoxy) phenyl ] fluorene and 4', 4-dimercaptodiphenyl sulfide in a solvent A; firstly, putting dissolved 9, 9-bis [ (2, 3-epoxypropoxy) phenyl ] fluorene into a reaction container, then adding a catalyst, then dropwise adding a 4', 4-dimercaptodiphenyl sulfide solution, continuing to react after the dropwise adding is finished, cooling to room temperature, carrying out reduced pressure distillation to remove impurities, and finally determining the epoxy value of the resin by a hydrochloric acid-acetone method;

(2) and (3) synthesis of a curing agent: dissolving o-dichlorobenzyl and thiourea in a solvent B, placing the solution in a reaction vessel, refluxing, filtering, and washing with a solvent C to obtain a white solid; dissolving the white solid in distilled water, beginning to dropwise add NaOH solution, refluxing, adjusting the pH value by using a neutralizing agent, extracting by using an extracting agent, drying, and finally carrying out reduced pressure distillation to obtain a curing agent 1, 2-benzenedimethylmercaptan;

(3) curing of the epoxy resin: adding the curing agent prepared in the step (2) into the epoxy resin solution prepared in the step (1) to obtain a dispersion liquid; and (3) spin-coating the dispersion liquid, and curing in a drying oven to obtain the sulfur-containing fluorene-containing high-refractive-index optical resin.

Further, the solvent A in the step (1) is N, N-dimethylacetamide (DMAc); the catalyst is a saturated methanol solution of LiOH.

Further, the solvent B in the step (2) is ethanol; the solvent C is a mixed solution of ethanol and diethyl ether; the neutralizer is concentrated sulfuric acid; the extractant is dichloromethane or ethyl acetate.

Further, the impurity in the step (1) is specifically methanol.

Further, the step (1) is specifically as follows: dissolving 9.25-13.875g of 9, 9-bis [ (2, 3-epoxypropoxy) phenyl ] fluorene in 20-30mL of solvent A, and dissolving 12.5-18.75g of 4' 4-dimercaptodiphenyl sulfide in 10-15mL of solvent A; firstly, putting a 9, 9-bis [ (2, 3-epoxypropoxy) phenyl ] fluorene solution into a 250mL three-neck flask, then adding 3-4 drops of catalyst, then beginning to dropwise add the prepared 4' 4-dimercaptodiphenyl sulfide solution for 15-25min, and continuing to react for 0.5-1.5h after dropwise adding is finished; and after the reaction is cooled to room temperature, carrying out reduced pressure distillation at-0.1-0 MPa and 40-45 ℃ for 1-1.5h to remove impurities, and finally determining the epoxy value of the resin by a hydrochloric acid-acetone method.

Further, the step (2) is specifically as follows: dissolving 9.98-14.97g of o-dichlorobenzyl and 8.68-13.02g of thiourea in 160mL of solvent B, placing the solution in a 250mL three-neck flask, and stirring and refluxing for 30-45 min; filtering, and washing with a solvent C to obtain a white solid; completely dissolving 9-10g of white solid in 100-150mL of distilled water, placing the solution in a 250mL three-neck flask, dropwise adding 42-50g of NaOH solution with the mass concentration of 15% -18%, refluxing for 3h, adjusting the pH value to 7-7.5 by using a neutralizing agent, and extracting by using an extracting agent; drying, and finally carrying out reduced pressure distillation at-0.1-0 MPa and 30-35 ℃ for 1-1.5h to obtain the product, namely the curing agent 1, 2-benzenedimethylmercaptan.

Further, the step (3) is specifically: adding the curing agent prepared in the step (2) into the epoxy resin solution prepared in the step (1) to obtain a dispersion liquid; wherein n (epoxy group): n (-SH) is 1: 0.8; spin-coating the dispersion liquid on a glass plate or a silicon wafer for 30-35s at the speed of 1800 plus 2000r/min by using a desktop spin coater, placing the glass plate or the silicon wafer in an oven for curing for 4-6h at the temperature of 100 plus 150 ℃, and finally preparing the fluorine-containing structure-containing optical resin with high refractive index.

Further, in step (3): and respectively dripping the dispersion liquid on a glass slide and a silicon chip, and spin-coating by adopting a self-leveling mode or a desk-top spin coater.

Further, in step (3): and during curing, the material is placed in an oven at 100 ℃ for curing for 1h, then the temperature is raised to 120 ℃ for curing for 2h, and finally the temperature is raised to 150 ℃ for curing for 2h, so that the sulfur-containing fluorene-containing high-refractive-index optical resin is obtained.

The invention has the beneficial effects that: the high-refractive-index optical resin containing the sulfur and the fluorene structure is prepared through simple and efficient reaction, and has good optical performance, high refractive index, high light transmittance, good heat resistance, good adhesive force and good mechanical property. The resin has good application prospect in LED packaging materials, antireflection coatings, optical lenses, optical element adhesives and the like.

Drawings

FIG. 1 is a nuclear magnetic resonance image of a sulfur-containing fluorene-containing high refractive index optical resin prepared in example 1.

FIG. 2 is a thermogravimetric plot of the sulfur-containing fluorene-containing structure-high refractive index optical resin prepared in example 1.

Detailed Description

Example 1

(1) Synthesis of epoxy resin: dissolving 9.25g of 9, 9-bis [ (2, 3-epoxypropoxy) phenyl ] fluorene in 25mL of N, N-dimethylacetamide, adding the solution into a 250mL three-neck flask with a condenser stirrer, dropwise adding 3-4 drops of saturated methanol solution of LiOH, dropwise adding a mixed solution of 12.5g of 4' 4-dimercaptodiphenyl sulfide and 10mL of N, N-dimethylacetamide while stirring at room temperature, after dropping for about 20min, continuing to react for 1h, cooling the exothermic reaction to room temperature, removing methanol by a rotary evaporator at-0.1 MPa and 40-45 ℃, and collecting a product for later use, wherein the product is the mixed solution of a polymer matrix and N, N-dimethylacetamide.

(2) And (3) synthesis of a curing agent: in a 250mL three-necked flask equipped with a condenser, a thermometer and a stirrer, 150mL of ethanol, 9.98g of o-dichlorobenzyl and 8.68g of thiourea were charged, stirred under reflux for 30min, and then filtered, and washed with a mixed solution of ethanol and ether to obtain a white solid. Dissolving the solid in 100mL of distilled water, placing the solution in a 250mL three-neck flask provided with a condenser, a thermometer and a stirrer, dropwise adding 42g of NaOH solution with the mass concentration of 15% while stirring, stirring and refluxing for 3h, and regulating the reactant with concentrated sulfuric acidAfter neutralization, extraction with dichloromethane, anhydrous MgSO₄Drying, and distilling under reduced pressure of-0.1 MPa and 30-35 deg.C to obtain 1, 2-benzenedimethylmercaptan.

(3) Curing of the epoxy resin: adding the curing agent prepared in the step (2) into the epoxy resin solution prepared in the step (1) to obtain a dispersion liquid, wherein n (epoxy group): n (-SH) is 1: 0.8. and then respectively dripping the solution on a glass slide and a silicon chip, spin-coating for 30s at the speed of 2000r/min by using a desktop spin coater, then placing the glass slide and the silicon chip in an oven for curing for 1h at the temperature of 100 ℃, then heating to 120 ℃ for curing for 2h, and finally heating to 150 ℃ for curing for 2h to obtain the optical resin film with the sulfur-containing fluorene-containing structure and high refractive index.

The nuclear magnetic resonance image of the prepared sulfur-containing fluorene-structured high-refractive-index optical resin is shown in fig. 1, wherein δ =2.74ppm is a proton peak of methylene connected with thiol on an epoxy group of the epoxy resin, a proton peak of methine appears at δ =2.88ppm, and a proton peak of methylene directly connected with the epoxy group appears at δ =3.92ppm, which indicates that epoxy groups are reserved at two ends of a molecular chain of a polymer matrix; δ =7.48ppm is the proton peak of hydrogen on the benzene ring, δ =1.59 ppm is the proton peak of methyl group between 2 benzene rings, δ =3.91ppm is the proton peak of methylene group connected to oxygen, δ =5.25ppm is the proton peak of hydroxyl group, δ =4.05ppm is the proton peak of methine group connected to hydroxyl group, δ =2.82 ppm is the proton peak of methylene group on 4' 4-dimercaptodiphenylsulfide, indicating that mercapto group and epoxy group successfully undergo ring-opening reaction and hydroxyl group is generated on the side chain.

The thermal weight loss curve of the prepared sulfur-containing fluorene structure-containing high-refractive-index optical resin is shown in fig. 2, wherein the thermal weight loss temperature of 1wr percent of the high-refractive-index resin is 217.6 ℃, the temperature of 5wt percent of the thermal weight loss object is 386.6 ℃, the thermal weight loss temperature of 10wt percent of the high-refractive-index resin is 411.3 ℃, and the temperature with the fastest weight loss rate is 427.3 ℃.