阅读说明：本技术 一种含硅大分子可见光引发剂 (Silicon-containing macromolecular visible photoinitiator ) 是由 管和平 于 2021-08-12 设计创作，主要内容包括：本发明属于光固化材料领域。本发明涉及一种含硅大分子可见光引发剂,以4-羟甲基-1,3-二氧-2-硫酮、溴代烷基酰氯、7-羟基-2-羧基硫杂蒽酮、烯丙基缩水甘油醚以及含氢硅氧烷作为原料,经过偶联、酯化、环氧开环、硅氢加成等多步骤反应得到了一种含硅大分子可见光引发剂材料。该新型光引发剂不仅有效解决现有技术中双组分光引发剂需要添加助引发剂而导致黄变且迁移致危害等以及可见光引发剂品种单一问题,同时还可具有难迁移析出、应用广泛、环保等优势,该新型材料尤其适用可见光LED等领域。(The invention belongs to the field of light-cured materials. The invention relates to a silicon-containing macromolecular visible light initiator, which is prepared from 4-hydroxymethyl-1, 3-dioxo-2-thioketone, bromoalkyl acyl chloride, 7-hydroxy-2-carboxythianthrone, allyl glycidyl ether and hydrogen-containing siloxane through coupling, esterification, epoxy ring opening, hydrosilylation and other multi-step reactions. The novel photoinitiator not only effectively solves the problems that in the prior art, a dual-component photoinitiator needs to be added with an auxiliary initiator to cause yellowing, migration causes harm and the like, and the variety of the visible photoinitiator is single, but also has the advantages of difficult migration and precipitation, wide application, environmental protection and the like, and the novel material is particularly suitable for the fields of visible light LEDs and the like.)

1. A silicon-containing macromolecular visible light initiator is characterized in that the structural formula is as follows:

wherein, x is 18-26, and m is 48-54.

2. A method for preparing a silicon-containing macromolecular visible light initiator is characterized by comprising the following steps: comprises the following steps:

(1) adding 1mol of hydroxythioxanthone and 1.1-1.5mol of triethylamine into 30mol of dichloromethane, carrying out ice-water bath, stirring, dissolving 1.1-1.5mol of bromoalkyl acyl chloride into 10mol of dichloromethane, slowly dripping into the solution, stirring for 6-12h, and standing at room temperature overnight; washing with 1M dilute hydrochloric acid solution, deionized water, saturated sodium bicarbonate solution and saturated sodium chloride solution for 5 times, separating, drying the organic phase with anhydrous magnesium sulfate, filtering, concentrating, and vacuum drying to obtain intermediate I;

(2) adding 1mol of I, 1.1-1.4mol of 7-hydroxy-2-carboxythioxanthone and 1.1-1.4mol of potassium carbonate into 50mol of DMF, heating to 110-; slowly adding 30mol of water, stirring for 30min, adding 50mol of dichloromethane, stirring for 30min, standing for layering, taking an organic phase, drying with anhydrous sodium sulfate, filtering, and performing rotary evaporation to obtain an intermediate product II;

(3) dissolving 1-1.2mol of II in 30mol of dichloromethane, slowly adding 1mol of allyl glycidyl ether, and stirring at room temperature for 0.5-2h to obtain an intermediate product III;

(4) weighing 1mol of III in a flask, dissolving hydrogen-containing polysiloxane containing 1-2mol of hydrogen in 30mol of anhydrous THF (tetrahydrofuran), protecting with argon, slowly heating to 45 ℃, adding 4-8mg/L of catalyst, stirring, heating in an oil bath to 80-90 ℃, reacting for 5-8h, cooling to room temperature, transferring the reaction solution into the flask, concentrating, sealing, wrapping with tin box paper, and refrigerating to obtain a target product IV.

3. The method for preparing silicon-containing macromolecular visible photoinitiator according to claim 2, wherein the method comprises the following steps: the steps are all operated under a yellow light lamp or in a dark place.

4. The method for preparing silicon-containing macromolecular visible photoinitiator according to claim 2, wherein the method comprises the following steps: the bromoalkyl acyl chloride is 4-bromobutyryl chloride, 2-bromobutyryl chloride, 3-bromopropionyl chloride, 5-bromovaleryl chloride or 11-bromoundecyl acyl chloride.

5. The method for preparing silicon-containing macromolecular visible photoinitiator according to claim 2, wherein the method comprises the following steps: the hydrogen content of the hydrogenpolysiloxane is 0.35-0.5 wt%.

6. The method for preparing silicon-containing macromolecular visible photoinitiator according to claim 2, wherein the method comprises the following steps: the catalyst is chloroplatinic acid, aluminum chloride or carbine.

Technical Field

The invention relates to a silicon-containing macromolecular visible light initiator. The invention belongs to the field of light-cured materials.

Background

The photocuring technology has the following characteristics: the solvent-free curing agent has the advantages of no solvent, high curing speed, energy conservation, environmental protection, good product performance, suitability for high-speed automatic production lines, and wide application in the fields of coating, printing ink, electronic communication, adhesives, dental curing, 3D printing and the like.

The light-cured material mainly comprises functionalized oligomer, monomer, photoinitiator and the like. The photoinitiator is an important component of the photocuring system, and the proportion of the photoinitiator is small but plays a role in determining the photocuring speed. The photoinitiator directly or indirectly absorbs light energy with a certain wavelength, the light energy is transited from a ground state to an excited state, and the generated active species initiate the crosslinking polymerization reaction. The photoinitiator can be divided into an ultraviolet photoinitiator (250-400nm) and a visible photoinitiator (400-700nm) according to different absorption radiant energies. The ultraviolet initiator is mainly sensitive to ultraviolet light, particularly 365nm ultraviolet light source, has almost no response to visible light, and is convenient for production and transportation. However, due to the advantages of special requirements (safety in use, penetration ability, harmlessness to human body, etc.) and the rapid development of visible light LEDs, the visible light and near infrared light photopolymerization technology has received great attention in recent years.

On the other hand, the existing hydrogen abstraction type photoinitiator belongs to a small molecular photoinitiator, and needs to be matched with a co-initiator for use, and the most commonly used co-initiator is tertiary amine, so that the defects of high viscosity, easy yellowing, easy migration, easy volatilization, low initiation efficiency, odor and the like exist. In order to solve the above problems, CN105693888B discloses a polymerizable thioxanthone visible light initiator containing acrylate or methacrylate and a preparation method thereof, which has good compatibility with a photocuring system, does not need to add any solvent or auxiliary agent during use, has the advantages of high initiation efficiency, environmental protection, low energy consumption and the like, but does not solve the yellowing problem by using tertiary amine as a hydrogen donor. Wuqingqing (design, synthesis and performance research of a single-component thioxanthone visible light initiator, 2016,9 of Wuhan university, Wuhan) prepares a thioxanthone-polysiloxane visible light initiator VI-PIs containing silicon-hydrogen bonds through hydrosilylation reaction of TX-A and low hydrogen-containing polysiloxane (H-PSO). The result shows that the VI-PIs are not only a high-efficiency single-component visible light initiator with antioxidant and polymerization inhibition functions, but also can improve the surface performance, the thermal stability and the like of the photocuring material. However, the yellowing problem is likewise not solved.

In view of the above, an environmentally friendly visible light initiator which is free from yellowing, low in migration precipitation and high in initiation efficiency has been developed as a heat generation point.

Disclosure of Invention

The invention aims to provide a silicon-containing macromolecular visible light initiator aiming at the problems that in the prior art, an auxiliary initiator needs to be added to a double-component photoinitiator, so that yellowing and migration damage are caused, and the variety of the visible light initiator is single. The novel material is particularly suitable for the field of visible light curing, and is prepared by taking 4-hydroxymethyl-1, 3-dioxo-2-thioketone, bromoalkyl acyl chloride, 7-hydroxy-2-carboxythianthrone, allyl glycidyl ether and hydrogen-containing siloxane as raw materials and carrying out multi-step reactions such as coupling, esterification, epoxy ring opening, hydrosilylation and the like to obtain the silicon-containing macromolecular visible light initiator material.

The technical scheme adopted by the invention for solving the technical problems is as follows:

a silicon-containing macromolecular visible light initiator has a structural formula as follows:

wherein, x is 18-26, and m is 48-54.

A preparation method of a silicon-containing macromolecular visible photoinitiator comprises the following steps:

(1) adding 1mol of hydroxythioxanthone and 1.1-1.5mol of triethylamine into 30mol of dichloromethane, carrying out ice-water bath, stirring, dissolving 1.1-1.5mol of bromoalkyl acyl chloride into 10mol of dichloromethane, slowly dripping into the solution, stirring for 6-12h, and standing at room temperature overnight; washing with 1M dilute hydrochloric acid solution, deionized water, saturated sodium bicarbonate solution and saturated sodium chloride solution for 5 times, separating, drying the organic phase with anhydrous magnesium sulfate, filtering, concentrating, and vacuum drying to obtain intermediate I;

(2) adding 1mol of I, 1.1-1.4mol of 7-hydroxy-2-carboxythioxanthone and 1.1-1.4mol of potassium carbonate into 50mol of DMF, heating to 110-; slowly adding 30mol of water, stirring for 30min, adding 50mol of dichloromethane, stirring for 30min, standing for layering, taking an organic phase, drying with anhydrous sodium sulfate, filtering, and performing rotary evaporation to obtain an intermediate product II;

(3) dissolving 1-1.2mol of II in 30mol of dichloromethane, slowly adding 1mol of allyl glycidyl ether, and stirring at room temperature for 0.5-2h to obtain an intermediate product III;

(4) weighing 1mol of III in a flask, dissolving hydrogen-containing polysiloxane containing 1-2mol of hydrogen in 30mol of anhydrous THF (tetrahydrofuran), protecting with argon, slowly heating to 45 ℃, adding 4-8mg/L of catalyst, stirring, heating in an oil bath to 80-90 ℃, reacting for 5-8h, cooling to room temperature, transferring the reaction solution into the flask, concentrating, sealing, wrapping with tin box paper, and refrigerating to obtain a target product IV.

Preferably, the steps are all operated under a yellow light lamp or in the absence of light.

Preferably, the bromoalkyl acid chloride is 4-bromobutyryl chloride, 2-bromobutyryl chloride, 3-bromopropionyl chloride, 5-bromovaleryl chloride or 11-bromoundecyl acid chloride.

Preferably, the hydrogen content of the hydrogenpolysiloxane is 0.35 to 0.5 wt%.

Preferably, the catalyst is chloroplatinic acid, aluminum chloride or carbene alkane.

The novel silicon-containing macromolecular visible light initiator provided by the invention has the following preparation process:

the invention has the beneficial effects that:

(1) the invention provides a silicon-containing macromolecular visible light initiator. The molecular chain simultaneously contains the thioxanthone initiator, a hydrogen donor five-membered ring thioketone structure and a silicon hydrogen structure, so that the problem of inverse electron transfer inherent in a conventional double-component system is avoided, the initiation efficiency is high, and the yellowing problem caused by amine serving as a common auxiliary initiator is avoided; in addition, the ultraviolet absorption of the photoinitiator is further red-shifted, and the photoinitiator is particularly suitable for the field of visible light initiation.

(2) According to the silicon-containing macromolecular visible light initiator provided by the invention, the chain structure of macromolecular siloxane forms chain entanglement of a molecular chain with a system, so that the problem of migration of the initiator is solved. The structure contains a large amount of Si elements, the Si elements have low atomic surface energy and can migrate to the surface of a system to form a surface film layer, and the functions of overcoming oxygen inhibition, resisting pollution and resisting heat can be achieved.

(3) The silicon-containing macromolecular visible light initiator provided by the invention has wide applicability in visible light LEDs, and is particularly suitable for the fields of visible light initiation, such as 3C, 3D printing, microelectronics and the like.

The specific implementation mode is as follows:

the present invention will be described in detail with reference to examples. It is to be understood, however, that the following examples are illustrative of embodiments of the present invention and are not to be construed as limiting the scope of the invention.

Example 1

A preparation method of a silicon-containing macromolecular visible light initiator comprises the following steps (all operated under a yellow light lamp):

(1) adding 1mol of hydroxythioxanthone and 1.3mol of triethylamine into 30mol of dichloromethane, carrying out ice-water bath, stirring, dissolving 1.3mol of 4-bromobutyryl chloride into 10mol of dichloromethane, slowly dripping into the solution, stirring for 8h, and standing at room temperature overnight; washing with 1M dilute hydrochloric acid solution, deionized water, saturated sodium bicarbonate solution and saturated sodium chloride solution for 5 times, separating, drying the organic phase with anhydrous magnesium sulfate, filtering, concentrating, and vacuum drying to obtain intermediate I;

the infrared data are as follows: 3501cm^-1: -OH disappearance; 1723cm^-1: -C ═ O is present; 988cm^-1: -C-S-is present; 582cm^-1: -C-Br is present.

(2) Adding 1mol of I, 1.2mol of 7-hydroxy-2-carboxythioxanthone and 1.2mol of potassium carbonate into 50mol of DMF, heating to 130 ℃, stirring strongly for 1h, cooling, standing, concentrating the solution in vacuum, and enriching residual components; slowly adding 30mol of water, stirring for 30min, adding 50mol of dichloromethane, stirring for 30min, standing for layering, taking an organic phase, drying with anhydrous sodium sulfate, filtering, and performing rotary evaporation to obtain an intermediate product II;

the infrared data are as follows: 3512cm^-1: -OH is present; 1562cm^-1、1250cm^-1、762cm^-1: a benzene ring is present; 1723cm^-1、1596cm^-1: -C ═ O is present; 988cm^-1: -C-S-is present; 582cm^-1: disappearance of-C-Br.

(3) Dissolving 1mol of II in 30mol of dichloromethane, slowly adding 1mol of allyl glycidyl ether, and stirring at room temperature for 2 hours to obtain an intermediate product III;

the infrared data are as follows: 3500cm^-1: -OH is present; 1611cm^-1: -C ═ C-is present;1562cm^-1、1250cm^-1、762cm^-1: a benzene ring is present; 1723cm^-1、1596cm^-1: -C ═ O is present; 988cm^-1: -C-S-is present; 910cm^-1: epoxy groups are absent.

(4) Weighing 1mol of III, 1.5mol of hydrogen-containing polysiloxane (x is 20, m is 50, and the hydrogen content is 0.4 wt%) in a flask, dissolving in 30mol of anhydrous THF, argon protecting, slowly heating to 45 ℃, adding 6mg/L of carbene alkane, stirring, heating in an oil bath to 90 ℃ for reaction for 5h, cooling to room temperature, transferring the reaction solution into the flask, concentrating, sealing, packaging with tin case paper, and refrigerating to obtain the target product IV.

The infrared data are as follows: 3500cm^-1: -OH is present; 1611cm^-1: -C ═ C — disappearance; 1562cm^-1、1250cm^-1、762cm^-1: a benzene ring is present; 1723cm^-1、1596cm^-1: -C ═ O is present; 988cm^-1: -C-S-is present; 2150cm^-1: -Si-H is present; 1258cm^-1、798cm^-1: -Si-C-is present; 970-1150cm^-1: -Si-O-Si-is present.

Example 2

A preparation method of a silicon-containing macromolecular visible light initiator comprises the following steps (operation for avoiding light):

(1) adding 1mol of hydroxythioxanthone and 1.1mol of triethylamine into 30mol of dichloromethane, carrying out ice-water bath, stirring, dissolving 1.1mol of 3-bromopropionyl chloride into 10mol of dichloromethane, slowly dripping into the solution, stirring for 12h, and standing at room temperature overnight; washing with 1M dilute hydrochloric acid solution, deionized water, saturated sodium bicarbonate solution and saturated sodium chloride solution for 5 times, separating, drying the organic phase with anhydrous magnesium sulfate, filtering, concentrating, and vacuum drying to obtain intermediate I;

the infrared data are as follows: 3501cm^-1: -OH disappearance; 1720cm^-1: -C ═ O is present; 987cm^-1: -C-S-is present; 588cm^-1: -C-Br is present.

(2) Adding 1mol of I, 1.4mol of 7-hydroxy-2-carboxythioxanthone and 1.4mol of potassium carbonate into 50mol of DMF, heating to 120 ℃, stirring strongly for 1h, cooling, standing, concentrating the solution in vacuum, and enriching residual components; slowly adding 30mol of water, stirring for 30min, adding 50mol of dichloromethane, stirring for 30min, standing for layering, taking an organic phase, drying with anhydrous sodium sulfate, filtering, and performing rotary evaporation to obtain an intermediate product II;

the infrared data are as follows: 3515cm^-1: -OH is present; 1564cm^-1、1254cm^-1、762cm^-1: a benzene ring is present; 1720cm^-1、1596cm^-1: -C ═ O is present; 987cm^-1: -C-S-is present; 588cm^-1: disappearance of-C-Br.

(3) Dissolving 1.2mol of II in 30mol of dichloromethane, slowly adding 1mol of allyl glycidyl ether, and stirring at room temperature for 0.5h to obtain an intermediate product III;

the infrared data are as follows: 3500cm^-1: -OH is present; 1610cm^-1: -C ═ C-is present; 1562cm^-1、1252cm^-1、762cm^-1: a benzene ring is present; 1723cm^-1、1596cm^-1: -C ═ O is present; 988cm^-1: -C-S-is present; 911cm^-1: epoxy groups are absent.

(4) Weighing 1mol of III in a flask, dissolving 1mol of hydrogen-containing polysiloxane (x is 18, m is 54, and the hydrogen content is 0.35 wt%) in 30mol of anhydrous THF, slowly heating to 45 ℃ under the protection of argon, adding 8mg/L of aluminum chloride, stirring, heating in an oil bath to 80 ℃ for reaction for 8h, cooling to room temperature, transferring the reaction solution into the flask, concentrating, sealing, packaging with tin box paper, and refrigerating to obtain the target product IV.

The infrared data are as follows: 3501cm^-1: -OH is present; 1610cm^-1: -C ═ C — disappearance; 1562cm^-1、1252cm^-1、763cm^-1: a benzene ring is present; 1723cm^-1、1596cm^-1: -C ═ O is present; 988cm^-1: -C-S-is present; 1261cm^-1、799cm^-1: -Si-C-is present; 970-1150cm^-1: -Si-O-Si-is present.

Example 3

A preparation method of a silicon-containing macromolecular visible light initiator comprises the following steps (all operated under a yellow light lamp):

(1) adding 1mol of hydroxythioxanthone and 1.5mol of triethylamine into 30mol of dichloromethane, carrying out ice-water bath, stirring, dissolving 1.5mol of 2-bromobutyryl chloride into 10mol of dichloromethane, slowly dripping into the solution, stirring for 6h, and standing at room temperature overnight; washing with 1M dilute hydrochloric acid solution, deionized water, saturated sodium bicarbonate solution and saturated sodium chloride solution for 5 times, separating, drying the organic phase with anhydrous magnesium sulfate, filtering, concentrating, and vacuum drying to obtain intermediate I;

the infrared data are as follows: 3501cm^-1: -OH disappearance; 1719cm^-1: -C ═ O is present; 987cm^-1: -C-S-is present; 590cm^-1: -C-Br is present.

(2) Adding 1mol of I, 1.2mol of 7-hydroxy-2-carboxythioxanthone and 1.2mol of potassium carbonate into 50mol of DMF, heating to 110 ℃, stirring strongly for 3 hours, cooling, standing, concentrating the solution in vacuum, and enriching residual components; slowly adding 30mol of water, stirring for 30min, adding 50mol of dichloromethane, stirring for 30min, standing for layering, taking an organic phase, drying with anhydrous sodium sulfate, filtering, and performing rotary evaporation to obtain an intermediate product II;

the infrared data are as follows: 3515cm^-1: -OH is present; 1564cm^-1、1254cm^-1、762cm^-1: a benzene ring is present; 1720cm^-1、1596cm^-1: -C ═ O is present; 987cm^-1: -C-S-is present; 590cm^-1: disappearance of-C-Br.

(3) Dissolving 1.1mol of II in 30mol of dichloromethane, slowly adding 1mol of allyl glycidyl ether, and stirring at room temperature for 1.5h to obtain an intermediate product III;

the infrared data are as follows: 3500cm^-1: -OH is present; 1610cm^-1: -C ═ C-is present; 1562cm^-1、1252cm^-1、762cm^-1: a benzene ring is present; 1723cm^-1、1597cm^-1: -C ═ O is present; 988cm^-1: -C-S-is present; 910cm^-1: epoxy groups are absent.

(4) Weighing 1mol of III, 2mol of hydrogen-containing polysiloxane (x is 26, m is 48, and the hydrogen content is 0.5 wt%) in a flask, dissolving in 30mol of anhydrous THF, protecting with argon, slowly heating to 45 ℃, adding 4mg/L chloroplatinic acid, stirring, heating in an oil bath to 85 ℃, reacting for 6h, cooling to room temperature, transferring the reaction solution into the flask, concentrating, sealing, packaging with tin box paper, and refrigerating to obtain the target product IV.

The infrared data are as follows: 3501cm^-1: -OH is present; 1610cm^-1: -C ═ C — disappearance; 1562cm^-1、1252cm^-1、763cm^-1: a benzene ring is present; 1723cm^-1、1597cm^-1: -C ═ O is present; 988cm^-1: -C-S-is present; 2150cm^-1: -Si-H is present; 1261cm^-1、799cm^-1: -Si-C-is present; 970-1150cm^-1: -Si-O-Si-is present.

Example 4

A preparation method of a silicon-containing macromolecular visible light initiator comprises the following steps (operation for avoiding light):

(1) adding 1mol of hydroxythioxanthone and 1.2mol of triethylamine into 30mol of dichloromethane, carrying out ice-water bath, stirring, dissolving 1.2mol of 11-bromoundecanoyl chloride into 10mol of dichloromethane, slowly dripping into the solution, stirring for 10h, and standing at room temperature overnight; washing with 1M dilute hydrochloric acid solution, deionized water, saturated sodium bicarbonate solution and saturated sodium chloride solution for 5 times, separating, drying the organic phase with anhydrous magnesium sulfate, filtering, concentrating, and vacuum drying to obtain intermediate I;

the infrared data are as follows: 3501cm^-1: -OH disappearance; 1714cm^-1: -C ═ O is present; 987cm^-1: -C-S-is present; 583cm^-1: -C-Br is present.

(2) Adding 1mol of I, 1.3mol of 7-hydroxy-2-carboxythioxanthone and 1.3mol of potassium carbonate into 50mol of DMF, heating to 120 ℃, stirring strongly for 2h, cooling, standing, concentrating the solution in vacuum, and enriching residual components; slowly adding 30mol of water, stirring for 30min, adding 50mol of dichloromethane, stirring for 30min, standing for layering, taking an organic phase, drying with anhydrous sodium sulfate, filtering, and performing rotary evaporation to obtain an intermediate product II;

the infrared data are as follows: 3515cm^-1: -OH is present; 1564cm^-1、1254cm^-1、762cm^-1: a benzene ring is present; 1715cm^-1、1596cm^-1: -C ═ O is present; 987cm^-1: -C-S-is present; 583cm^-1: disappearance of-C-Br.

(3) Dissolving 1.1mol of II in 30mol of dichloromethane, slowly adding 1mol of allyl glycidyl ether, and stirring at room temperature for 1h to obtain an intermediate product III;

the infrared data are as follows: 3500cm^-1: -OH is present; 1610cm^-1: -C ═ C-is present; 1562cm^-1、1252cm^-1、762cm^-1: a benzene ring is present; 1715cm^-1、1596cm^-1: -C ═ O is present; 988cm^-1: -C-S-is present; 910cm^-1: epoxy groups are absent.

(4) Weighing 1mol of III, 1.2mol of hydrogen-containing polysiloxane (x is 20, m is 50, and the hydrogen content is 0.4 wt%) in a flask, dissolving in 30mol of anhydrous THF, argon protecting, slowly heating to 45 ℃, adding 5mg/L chloroplatinic acid, stirring, heating in an oil bath to 85 ℃, reacting for 7 hours, cooling to room temperature, transferring the reaction solution into the flask, concentrating, sealing, packaging with tin box paper, and refrigerating to obtain the target product IV.

The infrared data are as follows: 3501cm^-1: -OH is present; 1610cm^-1: -C ═ C — disappearance; 1562cm^-1、1252cm^-1、763cm^-1: a benzene ring is present; 1715cm^-1、1596cm^-1: -C ═ O is present; 988cm^-1: -C-S-is present; 2150cm^-1: -Si-H is present; 1261cm^-1、799cm^-1: -Si-C-is present; 970-1150cm^-1: -Si-O-Si-is present.

Example 5

A preparation method of a silicon-containing macromolecular visible light initiator comprises the following steps (all operated under a yellow light lamp):

(1) adding 1mol of hydroxythioxanthone and 1.4mol of triethylamine into 30mol of dichloromethane, carrying out ice-water bath, stirring, dissolving 1.4mol of 5-bromovaleryl chloride into 10mol of dichloromethane, slowly dripping into the solution, stirring for 8h, and standing at room temperature overnight; washing with 1M dilute hydrochloric acid solution, deionized water, saturated sodium bicarbonate solution and saturated sodium chloride solution for 5 times, separating, drying the organic phase with anhydrous magnesium sulfate, filtering, concentrating, and vacuum drying to obtain intermediate I;

the infrared data are as follows: 3501cm^-1: -OH disappearance; 1714cm^-1: -C ═ O is present; 987cm^-1: -C-S-is present; 588cm^-1: -C-Br is present.

(2) Adding 1mol of I, 1.1mol of 7-hydroxy-2-carboxythioxanthone and 1.1mol of potassium carbonate into 50mol of DMF, heating to 130 ℃, stirring strongly for 2h, cooling, standing, concentrating the solution in vacuum, and enriching residual components; slowly adding 30mol of water, stirring for 30min, adding 50mol of dichloromethane, stirring for 30min, standing for layering, taking an organic phase, drying with anhydrous sodium sulfate, filtering, and performing rotary evaporation to obtain an intermediate product II;

the infrared data are as follows: 3515cm^-1: -OH is present; 1564cm^-1、1254cm^-1、762cm^-1: a benzene ring is present; 1715cm^-1、1599cm^-1: -C ═ O is present; 987cm^-1: -C-S-is present; 588cm^-1: disappearance of-C-Br.

(3) Dissolving 1.2mol of II in 30mol of dichloromethane, slowly adding 1mol of allyl glycidyl ether, and stirring at room temperature for 1h to obtain an intermediate product III;

the infrared data are as follows: 3500cm^-1: -OH is present; 1610cm^-1: -C ═ C-is present; 1562cm^-1、1252cm^-1、762cm^-1: a benzene ring is present; 1720cm^-1、1599cm^-1: -C ═ O is present; 988cm^-1: -C-S-is present; 910cm^-1: epoxy groups are absent.

(4) Weighing 1mol of III, 1.4mol of hydrogen-containing polysiloxane (x is 25, m is 54, and the hydrogen content is 0.45 wt%) in a flask, dissolving in 30mol of anhydrous THF, argon protecting, slowly heating to 45 ℃, adding 7mg/L of aluminum chloride, stirring, heating in an oil bath to 80 ℃, reacting for 7h, cooling to room temperature, transferring the reaction solution into the flask, concentrating, sealing, packaging with tin box paper, and refrigerating to obtain the target product IV.

The infrared data are as follows: 3501cm^-1: -OH is present; 1610cm^-1: -C ═ C — disappearance; 1562cm^-1、1252cm^-1、763cm^-1: a benzene ring is present; 1721cm^-1、1599cm^-1: -C ═ O is present; 988cm^-1: -C-S-is present; 2150cm^-1: -Si-H is present; 1261cm^-1、799cm^-1: -Si-C-is present; 970-1150cm^-1: -Si-O-Si-is present.

The photoinitiator obtained in specific example 1 was used as a base material in practical examples and applied to a photocurable coating.

Application example 1

The photocuring coating comprises the following raw materials in parts by weight: UV resin SM 620255 parts, TMPTA 15 parts, TPGDA 15 parts, butyl acrylate 12 parts and target product IV 3 parts.

The preparation method comprises the following steps: mixing the raw materials according to the weight part, coating the mixture on PET containing a base coat, and performing UV (light intensity of 50 mW/cm)²) The coating was irradiated under light for 60s to give a dry film 2 μm thick.

Application example 2

The photocuring coating comprises the following raw materials in parts by weight: UV resin SM 620257 parts, TMPTA 15 parts, TPGDA 15 parts, butyl acrylate 12 parts and target product IV 1 parts.

The preparation method comprises the following steps: mixing the raw materials according to the weight part, coating the mixture on PET containing a base coat, and performing UV (light intensity of 50 mW/cm)²) The coating was irradiated under light for 180s to give a dry film 2 μm thick.

Application example 3

The photocuring coating comprises the following raw materials in parts by weight: UV resin SM 620253 parts, TMPTA 15 parts, TPGDA 15 parts, butyl acrylate 12 parts and target product IV 5 parts.

The preparation method comprises the following steps: mixing the raw materials according to the weight part, coating the mixture on PET containing a base coat, and performing UV (light intensity of 50 mW/cm)²) The coating was irradiated under light for 30 seconds to give a dry film 2 μm thick.

Application example 4

The photocuring coating comprises the following raw materials in parts by weight: UV resin SM 620255 parts, TMPTA 15 parts, TPGDA 15 parts, butyl acrylate 12 parts and target product IV 3 parts.

The preparation method comprises the following steps: mixing the raw materials according to the weight part, coating the mixture on PET containing a base coat, and performing UV (light intensity of 50 mW/cm)²) The coating was irradiated under light for 120s to give a dry film 2 μm thick.

Application examples comparative examples 1-3 application example 1 was used as a control.

Practical example comparative example 1

The photocuring coating comprises the following raw materials in parts by weight: UV resin SM 620255 parts, TMPTA 15 parts, TPGDA 15 parts, butyl acrylate 12 parts and ITX 3 parts.

The preparation method comprises the following steps: mixing the raw materials according to the weight part, coating the mixture on PET containing a base coat, and performing UV (light intensity of 50 mW/cm)²) The coating was irradiated under light for 60s to give a dry film 2 μm thick.

Practical example comparative example 2

The photocuring coating comprises the following raw materials in parts by weight: UV resin SM 620255 parts, TMPTA 15 parts, TPGDA 15 parts, butyl acrylate 12 parts, ITX 3 parts and EDAB 3 parts.

The preparation method comprises the following steps: mixing the raw materials according to the weight part, coating the mixture on PET containing a base coat, and performing UV (light intensity of 50 mW/cm)²) The coating was irradiated under light for 60s to give a dry film 2 μm thick.

Practical example comparative example 3

The photocuring coating comprises the following raw materials in parts by weight: UV resin SM 620255 parts, TMPTA 15 parts, TPGDA 15 parts, butyl acrylate 12 parts, BP 3 parts and EDAB 3 parts.

The preparation method comprises the following steps: mixing the raw materials according to the weight part, coating the mixture on PET containing a base coat, and performing UV (light intensity of 50 mW/cm)²) The coating was irradiated under light for 60s to give a dry film 2 μm thick.

Physical properties including migration, yellowing, initiation efficiency, etc. of the macro photoinitiators prepared in application examples 1 to 4 of the present invention and comparative examples 1 to 3 were measured, respectively, and the results are shown in table 1.

Table 1 physical test properties of the examples

Firstly, as can be seen from table 1, the silicon-containing macromolecular visible photoinitiator of the present invention is compared with the currently commonly used small molecular photoinitiator ITX and two components ITX + EDAB, BP + EDAB; the product of the invention has maximum ultraviolet absorption at more than 400nm and can play an important role in the field of visible light curing.

Secondly, the silicon-containing macromolecular visible light initiator has a large number of siloxane structures in the macromolecular chain structure, has high mobility and can migrate to the surface of the structure. Firstly, the macromolecular chain structure and the system have larger chain entanglement and have no problem of migration and precipitation, so the odor is not generated; secondly, the structure simultaneously contains a thioketone ring structure as an intramolecular hydrogen donor, so that the problem of yellowing caused by the use of tertiary amine is avoided, the same molecular chain is favorable for energy transfer, and the initiation efficiency is higher (the double bond conversion rate is high, and t (R) is higher_p(max)) Lower due to less efficient diffusion of macromolecules). Therefore, the product has the advantages of no odor, no yellowing, no oxygen inhibition, difficult migration and precipitation, more environmental protection and the like;

thirdly, compared with the conventional common micromolecular photoinitiator, the silicon-containing macromolecular visible photoinitiator has a larger water contact angle and hydrophobicity of more than 90 degrees, and simultaneously, the heat resistance is improved due to the high chemical bond energy of silane.

In summary, compared with the existing photoinitiator, the silicon-containing macromolecular visible photoinitiator disclosed by the invention not only overcomes the defects of yellowing and easy migration and precipitation caused by the fact that the traditional double-component micromolecular photoinitiator needs an auxiliary initiator (common tertiary amine), can enrich the types of the visible photoinitiator, but also has the advantages of no oxygen inhibition, high initiation efficiency, hydrophobicity and thermal stability.

The test method comprises the following steps:

(1) odor: the lower the odor, the less migration is indicated, as evaluated by the direct fan-smelling method.

(2) Ultraviolet absorption lambda_max: the corresponding wavelength of the ultraviolet visible spectrometer when testing the maximum molar absorption coefficient of the ultraviolet visible spectrometer under the corresponding photoinitiator。

(3) Mobility: and (3) soaking the sample to be tested in acetonitrile for 24h in a 40 ℃ oven, preparing the same concentration, and testing the molar absorption coefficient of the sample under the corresponding photoinitiator by using an ultraviolet-visible spectrometer. Migration representation method: 5 is optimal and 1 is worst.

(4) Yellowing: the film was evaluated by visual observation, and the darker the color of the film, the more severe the yellowing. Method for expression of yellowing: 5 is colorless, most preferably, 1 is dark, worst.

(5) Oxygen inhibition and initiation efficiency test of double bond:

the test method comprises the following steps: the polymerization kinetics of the photocurable resin was monitored by a series of real-time infrared spectroscopy. Coating a sample containing photoinitiator on a KBr salt sheet, then putting into RTIR, irradiating with an ultraviolet point source for 120s for curing, wherein the light intensity is measured by a UV-A ultraviolet radiometer and is set to 80mW/cm². By monitoring the near infrared region C-H at 776-828 cm-^-1The change in the absorption peak area of (2) intuitively reflects the degree of progress of polymerization. The double bond conversion rate (DC) of the polymerization system can be calculated by combining OMNIC 8.2 infrared software and Excel data processing software with a formula, each sample is tested and repeated for 3 times, and an average value is taken.

Wherein DC represents the conversion rate of carbon-carbon double bonds when the illumination time is t, A₀Represents the initial area of the double bond absorption peak before illumination, A_tRepresents the double bond absorption peak area at the time of illumination t.

(6)t(R_p(max)) S: the time required for reaching the maximum polymerization rate is monitored by series of real-time infrared spectrums in the polymerization kinetic process of the light-cured resin, and a time t-polymerization rate R is obtained by derivation of a time-conversion rate curve_pCurve line.

(7) Contact angle: the test was carried out according to the method described in ASTM D7334-2008 (2013). The larger the water contact angle value, the lower the surface tension, and the more excellent the stain resistance.

(8) Heat resistance: TGA comprehensive thermal analyzer, argon atmosphere, heating rate 10 deg.C/min.

In light of the foregoing description of the preferred embodiment of the present invention, many modifications and variations will be apparent to those skilled in the art without departing from the spirit and scope of the invention. The technical scope of the present invention is not limited to the content of the specification, and must be determined according to the scope of the claims.