阅读说明：本技术 一种高效通用型紫外光引发剂的制备工艺 (Preparation process of efficient universal ultraviolet initiator ) 是由 陈江 王如龙 杜红伟 于 2021-07-22 设计创作，主要内容包括：本发明公开了一种高效通用型紫外光引发剂的制备工艺,属于引发剂领域。一种高效通用型紫外光引发剂的制备工艺,紫外光引发剂包括自由基型光引发剂、阳离子型光引发剂和光敏剂,由基型光引发剂包括：MTB,改性2,2-二甲氧基苯偶酰缩酮,BAPO,2,4,6-三甲基二苯甲酮,甲基二苯甲酮；阳离子型光引发剂包括：异丙基二茂铁六氟憐酸盐,1,3-双(二氰基亚甲基)茚-二苯基碘鎓盐；光敏剂为乙酰丙酮钴；它可以实现扩大可吸收光照的区间范围,将部分可见光和紫外光均可被光引发剂吸收,可使用于更多的应用场景。(The invention discloses a preparation process of an efficient universal ultraviolet light initiator, belonging to the field of initiators. A preparation process of a high-efficiency universal ultraviolet light initiator comprises a free radical type photoinitiator, a cationic photoinitiator and a photosensitizer, wherein the radical type photoinitiator comprises: MTB, modified 2, 2-dimethoxybenzil ketal, BAPO, 2,4, 6-trimethylbenzophenone, methylbenzophenone; the cationic photoinitiator comprises: isopropyl ferrocene hexafluoro acid salt, 1, 3-bis (dicyanomethylene) indene-diphenyliodonium salt; the photosensitizer is cobalt acetylacetonate; the ultraviolet light absorption device can expand the range of the region capable of absorbing the illumination, can absorb part of visible light and ultraviolet light by the photoinitiator, and can be used for more application scenes.)

1. A preparation process of a high-efficiency universal ultraviolet light initiator is characterized by comprising the following steps: the ultraviolet light initiator comprises a free radical type photoinitiator, a cationic photoinitiator and a photosensitizer;

the free radical type photoinitiator comprises the following components in parts by weight:

20-30 parts of sulfur-containing benzoin derivative MTB,

MTB has a structural formula as follows:

15-25 parts of modified 2, 2-dimethoxy benzil ketal,

15-25 parts of BAPO (B-butyl acrylate),

BAPO has the structural formula:

5-10 parts of 2,4, 6-trimethylbenzophenone,

5-10 parts of methylbenzophenone;

the cationic photoinitiator comprises the following components in parts by weight:

5-7 parts of isopropyl ferrocene hexafluoro acid salt,

5-7 parts of 1, 3-bis (dicyanomethylene) indene-diphenyl iodonium salt;

the photosensitizer is 5-8 parts by weight of cobalt acetylacetonate.

2. The process for preparing the high-efficiency universal ultraviolet photoinitiator according to claim 1, wherein the process comprises the following steps: the free radical type photoinitiator comprises the following components in parts by weight: 20 parts of sulfur-containing benzoin derivative MTB, 15 parts of modified 2, 2-dimethoxybenzil ketal, 15 parts of BAPO, 5 parts of 2,4, 6-trimethylbenzophenone and 5 parts of methylbenzophenone;

the cationic photoinitiator comprises the following components in parts by weight: 5 parts of isopropyl ferrocene hexafluoro acid salt; 5 parts of 1, 3-bis (dicyanomethylene) indene-diphenyliodonium salt.

3. The process for preparing the high-efficiency universal ultraviolet photoinitiator according to claim 1, wherein the process comprises the following steps: the free radical type photoinitiator comprises the following components in parts by weight: 30 parts of sulfur-containing benzoin derivative MTB, 25 parts of modified 2, 2-dimethoxybenzil ketal, 25 parts of BAPO, 10 parts of 2,4, 6-trimethylbenzophenone and 510 parts of methylbenzophenone;

the cationic photoinitiator comprises the following components in parts by weight: 7 parts of isopropyl ferrocene hexafluoro acid salt; 7 parts of 1, 3-bis (dicyanomethylene) indene-diphenyliodonium salt.

4. The process for preparing the high-efficiency universal ultraviolet photoinitiator according to claim 1, wherein the process comprises the following steps: the free radical type photoinitiator comprises the following components in parts by weight: 30 parts of sulfur-containing benzoin derivative MTB, 25 parts of modified 2, 2-dimethoxybenzil ketal, 25 parts of BAPO, 10 parts of 2,4, 6-trimethylbenzophenone and 10 parts of methylbenzophenone;

the cationic photoinitiator comprises the following components in parts by weight: 5 parts of isopropyl ferrocene hexafluoro acid salt; 5 parts of 1, 3-bis (dicyanomethylene) indene-diphenyliodonium salt.

5. The process for preparing the high-efficiency universal ultraviolet photoinitiator according to claim 1, wherein the process comprises the following steps: the free radical type photoinitiator comprises the following components in parts by weight: 20 parts of sulfur-containing benzoin derivative MTB, 15 parts of modified 2, 2-dimethoxybenzil ketal, 15 parts of BAPO, 5 parts of 2,4, 6-trimethylbenzophenone and 5 parts of methylbenzophenone;

the cationic photoinitiator comprises the following components in parts by weight: 7 parts of isopropyl ferrocene hexafluoro acid salt; 7 parts of 1, 3-bis (dicyanomethylene) indene-diphenyliodonium salt.

6. The process for preparing the high-efficiency universal ultraviolet photoinitiator according to claim 1, wherein the process comprises the following steps: the photoinitiator is prepared by a preparation method comprising the following steps:

s101, putting MTB, the modified 2, 2-dimethoxybenzil ketal, BAPO, 2,4, 6-trimethylbenzophenone and methylbenzophenone into acetone for dissolving, and putting into a constant-pressure dropping funnel;

s102, dropwise adding the solution in the S101 into a three-neck flask at the temperature of 15-20 ℃, wherein the dropwise adding speed is 1-3S/drop;

s103, stirring the solution in the S102 for 15-20min at the temperature of 15-20 ℃;

s104, placing isopropyl ferrocene hexafluoro acid salt and 1, 3-bis (dicyanomethylene) indene-diphenyliodonium salt in acetone for dissolving, and sequentially adding the dissolved solution into a three-neck flask in a dropwise manner at the temperature of 15-20 ℃, wherein the dropwise adding speed is 1-3S/drop;

s105, adding a photosensitizer into the mixed solution of the S104;

s106, stirring the mixed solution in the S105 for 15-20min at the temperature of 15-20 ℃;

s107, cooling in an ice-water bath, pouring the reaction solution into an ice-water mixture, stirring, performing suction filtration, washing with water, and washing with petroleum ether;

and S108, placing the product of the S107 in a vacuum oven at 50 ℃, and drying for 24h to obtain a final product.

Technical Field

The invention belongs to the field of initiators, and particularly relates to a preparation process of a high-efficiency universal ultraviolet initiator.

Background

Ultraviolet curing is a technique for curing liquid reactive substrates, such as reactive substrates containing reactive groups such as double bonds, epoxy groups, etc., into solid using ultraviolet light as a radiation source. The rapid development of the photocuring technology is promoted by the increasingly important environmental protection and energy conservation, and the internal reason is that the photocuring technology has incomparable advantages compared with the traditional surface treatment, and the advantages can be summarized by the characteristics of '5E': effective, capable of being widely applied, economical, energy saving and environment friendly.

Uv curable systems generally comprise three components: oligomer, reactive diluent or monomer, photoinitiator. The photoinitiator is a key component, directly determines the speed and conditions of ultraviolet curing, and greatly influences the performance of ultraviolet curing products.

The photoinitiator is a substance which can generate active species, such as free radicals, cations, anions and the like, under the irradiation of light to initiate polymerization crosslinking reaction. At present, the application is the most at home and abroad, the technology is the ultraviolet curing, namely, the used photoinitiator is the ultraviolet initiator. The ultraviolet light absorption interval of the ultraviolet light initiators is 250-400 nm.

However, most photoinitiators with single property have poor universality, have narrow corresponding acceptable light absorption intervals, and cannot be applied to more application scenes.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a preparation process of an efficient universal ultraviolet light initiator, which can expand the range of the interval capable of absorbing light, can absorb part of visible light and ultraviolet light by the photoinitiator, and can be used in more application scenes.

The invention relates to a preparation process of a high-efficiency universal ultraviolet photoinitiator.

Free radical photoinitiators include:

the sulfur-containing benzoin derivative MTB,

MTB has a structural formula as follows:the ultraviolet absorption width of MTB is far greater than that of benzoin, so that the MTB can be cracked to generate free radicals, and can generate a plurality of free radicals through intramolecular hydrogen abstraction, and the initiation efficiency is high.

The modified 2, 2-dimethoxy benzil ketal and the 2, 2-dimethoxy benzil ketal modified by the large conjugated group have high photoinitiation activity and no dark polymerization, and compared with the common 2, 2-dimethoxy benzil ketal, the ultraviolet absorbance and the ultraviolet absorption range are both greatly improved, and the modified 2, 2-dimethoxy benzil ketal can be absorbed even in a visible light region. The typical molecular structure after modification with pyrene is as follows:

BAPO，

BAPO has the structural formula:the BAPO has an absorption wavelength of a visible light region of 450nm, high activity after photolysis and multiple free radicals generated per molecule.

2,4, 6-trimethylbenzophenone and 2,4, 6-trimethylbenzophenone are used as initiators.

Methyl benzophenone, methyl benzophenone is a hydrogen donor.

The mixture of the 2,4, 6-trimethylbenzophenone and the methylbenzophenone is colorless liquid, the solubility in a diluent is good, the ultraviolet light utilization rate is high, the methylbenzophenone contains a hydrogen donor in a molecule, the methylbenzophenone is an effective photoinitiator when being used alone, and the initiation efficiency can be improved by 10-12 times when the photoinitiator is compounded with the 2,4, 6-trimethylbenzophenone.

The cationic photoinitiator comprises:

isopropyl ferrocene hexafluoro acid salt. The light absorption range of the isopropyl ferrocene hexafluoro acid salt is within the range of 240-540nm, such as the absorption in the ultraviolet region (240-250nm, 390-400nm), and the absorption in the visible region (530-540nm), which is both an ultraviolet light initiator and a visible light initiator, so that the universality is strong.

The 1, 3-bis (dicyanomethylene) indene-diphenyliodonium salt and the 1, 3-bis (dicyanomethylene) indene-diphenyliodonium salt are free radical cation dual-curing photoinitiators, have wider ultraviolet visible light absorption area compared with common diphenyliodonium hexafluorophosphate and have better initiation performance.

The photosensitizer is cobalt acetylacetonate.

As a further improvement of the invention, the free radical photoinitiator comprises the following components in parts by weight: 20-30 parts of MTB, 15-25 parts of modified 2, 2-dimethoxybenzil ketal, 15-25 parts of BAPO, 5-10 parts of 2,4, 6-trimethylbenzophenone and 5-10 parts of methylbenzophenone.

As a further improvement of the invention, the cationic photoinitiator comprises the following components in parts by weight: 5-7 parts of isopropyl ferrocene hexafluoro acid salt and 5-7 parts of 1, 3-bis (dicyanomethylene) indene-diphenyliodonium salt.

As a further improvement of the invention, the free radical photoinitiator comprises the following components in parts by weight: 20 parts of sulfur-containing benzoin derivative MTB, 15 parts of modified 2, 2-dimethoxybenzil ketal, 15 parts of BAPO, 5 parts of 2,4, 6-trimethylbenzophenone and 5 parts of methylbenzophenone.

The cationic photoinitiator comprises the following components in parts by weight: 5 parts of isopropyl ferrocene hexafluoro acid salt. 5 parts of 1, 3-bis (dicyanomethylene) indene-diphenyliodonium salt.

As a further improvement of the invention, the free radical photoinitiator comprises the following components in parts by weight: 30 parts of sulfur-containing benzoin derivative MTB, 25 parts of modified 2, 2-dimethoxybenzil ketal, 25 parts of BAPO, 10 parts of 2,4, 6-trimethylbenzophenone and 510 parts of methylbenzophenone.

The cationic photoinitiator comprises the following components in parts by weight: 7 parts of isopropyl ferrocene hexafluoro acid salt. 7 parts of 1, 3-bis (dicyanomethylene) indene-diphenyliodonium salt.

As a further improvement of the invention, the free radical photoinitiator comprises the following components in parts by weight: 30 parts of sulfur-containing benzoin derivative MTB, 25 parts of modified 2, 2-dimethoxybenzil ketal, 25 parts of BAPO, 10 parts of 2,4, 6-trimethylbenzophenone and 10 parts of methylbenzophenone.

The cationic photoinitiator comprises the following components in parts by weight: 5 parts of isopropyl ferrocene hexafluoro acid salt. 5 parts of 1, 3-bis (dicyanomethylene) indene-diphenyliodonium salt.

As a further improvement of the invention, the free radical photoinitiator comprises the following components in parts by weight: 20 parts of sulfur-containing benzoin derivative MTB, 15 parts of modified 2, 2-dimethoxybenzil ketal, 15 parts of BAPO, 5 parts of 2,4, 6-trimethylbenzophenone and 5 parts of methylbenzophenone.

The cationic photoinitiator comprises the following components in parts by weight: 7 parts of isopropyl ferrocene hexafluoro acid salt. 7 parts of 1, 3-bis (dicyanomethylene) indene-diphenyliodonium salt.

As a further improvement of the invention, the photoinitiator is prepared by a preparation method comprising the following steps:

s101, dissolving MTB, the modified 2, 2-dimethoxybenzil ketal, BAPO, 2,4, 6-trimethylbenzophenone and methylbenzophenone in acetone, and placing the mixture in a constant-pressure dropping funnel.

And S102, dropwise adding the solution in the S101 into a three-neck flask at the temperature of 15-20 ℃, wherein the dropwise adding speed is 1-3S/drop.

S103, stirring the solution in the S102 for 15-20min at the temperature of 15-20 ℃.

S104, dissolving isopropyl ferrocene hexafluoro acid salt and 1, 3-bis (dicyanomethylene) indene-diphenyliodonium salt in acetone, and sequentially adding the solution into a three-neck flask in a dropwise manner at the temperature of 15-20 ℃ at the dropwise speed of 1-3S/drop.

And S105, adding a photosensitizer into the mixed solution of the S104.

And S106, stirring the mixed solution in the S105 for 15-20min at the temperature of 15-20 ℃.

And S107, cooling in an ice-water bath, pouring the reaction solution into the ice-water mixture, stirring, performing suction filtration, washing with water, and washing with petroleum ether.

And S108, placing the product of the S107 in a vacuum oven at 50 ℃, and drying for 24h to obtain a final product.

Compared with the prior art, the invention has the beneficial effects that:

the photoinitiator composition has the capability of generating active species in an ultraviolet region, and can also cause oligomer to initiate polymerization crosslinking reaction in a part of visible light region; and the advantages of the free radical photoinitiator and the cationic photoinitiator are integrated, and the photocuring rate is obviously improved under the condition of keeping higher photoinitiation activity.

Detailed Description

A preparation process of a high-efficiency universal ultraviolet light initiator comprises a free radical type photoinitiator, a cationic photoinitiator and a photosensitizer.

Free radical photoinitiators include:

the sulfur-containing benzoin derivative MTB has an ultraviolet absorption width far greater than that of benzoin, can be cracked to generate free radicals, can generate a plurality of free radicals through intramolecular hydrogen abstraction, and has high initiation efficiency.

The modified 2, 2-dimethoxybenzil ketal is the 2, 2-dimethoxybenzil ketal modified by pyrene, has high photoinitiation activity, does not have dark polymerization, and has greatly improved ultraviolet absorbance and ultraviolet absorption range and even has absorption in a visible light region compared with the common 2, 2-dimethoxybenzil ketal.

BAPO, the absorption wavelength of BAPO can reach a visible light region of 450nm, the activity is high after photolysis, and the number of free radicals generated in each molecule is large.

2,4, 6-trimethylbenzophenone and 2,4, 6-trimethylbenzophenone are used as initiators.

Methyl benzophenone, methyl benzophenone is a hydrogen donor.

The mixture of the 2,4, 6-trimethylbenzophenone and the methylbenzophenone is colorless liquid, the solubility in a diluent is good, the ultraviolet light utilization rate is high, the methylbenzophenone contains a hydrogen donor in a molecule, the methylbenzophenone is an effective photoinitiator when being used alone, and the initiation efficiency can be improved by 10-12 times when the photoinitiator is compounded with the 2,4, 6-trimethylbenzophenone.

The cationic photoinitiator comprises:

isopropyl ferrocene hexafluoro acid salt. The light absorption range of the isopropyl ferrocene hexafluoro acid salt is within the range of 240-540nm, such as the absorption in the ultraviolet region (240-250nm, 390-400nm), and the absorption in the visible region (530-540nm), which is both an ultraviolet light initiator and a visible light initiator, so that the universality is strong.

The 1, 3-bis (dicyanomethylene) indene-diphenyliodonium salt and the 1, 3-bis (dicyanomethylene) indene-diphenyliodonium salt are free radical cation dual-curing photoinitiators, have wider ultraviolet visible light absorption area compared with common diphenyliodonium hexafluorophosphate and have better initiation performance.

The photosensitizer is cobalt acetylacetonate.

The free radical type photoinitiator comprises the following components in parts by weight: 20-30 parts of MTB, 15-25 parts of modified 2, 2-dimethoxybenzil ketal, 15-25 parts of BAPO, 5-10 parts of 2,4, 6-trimethylbenzophenone and 5-10 parts of methylbenzophenone.

The cationic photoinitiator comprises the following components in parts by weight: 5-7 parts of isopropyl ferrocene hexafluoro acid salt and 5-7 parts of 1, 3-bis (dicyanomethylene) indene-diphenyliodonium salt.

The photoinitiator is prepared by a preparation method comprising the following steps:

s101, dissolving MTB, the modified 2, 2-dimethoxybenzil ketal, BAPO, 2,4, 6-trimethylbenzophenone and methylbenzophenone in acetone, and placing the mixture in a constant-pressure dropping funnel.

And S102, dropwise adding the solution in the S101 into a three-neck flask at the temperature of 15-20 ℃, wherein the dropwise adding speed is 1-3S/drop.

S103, stirring the solution in the S102 for 15-20min at the temperature of 15-20 ℃.

S104, dissolving isopropyl ferrocene hexafluoro acid salt and 1, 3-bis (dicyanomethylene) indene-diphenyliodonium salt in acetone, and sequentially adding the solution into a three-neck flask in a dropwise manner at the temperature of 15-20 ℃ at the dropwise speed of 1-3S/drop.

And S105, adding a photosensitizer into the mixed solution of the S104.

And S106, stirring the mixed solution in the S105 for 15-20min at the temperature of 15-20 ℃.

And S107, cooling in an ice-water bath, pouring the reaction solution into the ice-water mixture, stirring, performing suction filtration, washing with water, and washing with petroleum ether.

And S108, placing the product of the S107 in a vacuum oven at 50 ℃, and drying for 24h to obtain a final product.

The first embodiment is as follows: the photoinitiator of the invention is prepared from the following raw materials in proportion:

example two: the photoinitiator of the invention is prepared from the following raw materials in proportion:

example three: the photoinitiator of the invention is prepared from the following raw materials in proportion:

example four: the photoinitiator of the invention is prepared from the following raw materials in proportion:

example five: the photoinitiator of the invention is prepared from the following raw materials in proportion:

example six: the photoinitiator of the invention is prepared from the following raw materials in proportion:

example seven: the photoinitiator of the invention is prepared from the following raw materials in proportion:

comparative example one: the photoinitiator is prepared from the following raw materials in percentage by weight:

comparative example two: the photoinitiator is prepared from the following raw materials in percentage by weight:

comparative example three: the photoinitiator is prepared from the following raw materials in percentage by weight:

the curing speed detection methods of examples one to seven and comparative examples one to three were as follows:

under the same environment, the curing speed measurement was performed under different illumination intervals for each small portion of the obtained material obtained by equally dividing each of the obtained materials in each of examples and comparative examples into seven portions. The different illumination intervals are as follows: 200-250 nm; 250-300 nm; 300-350 nm; 350-400 nm; 400-450 nm; 450-500 nm; 500-550 nm.

Coating a photoinitiator on glass, starting reaction of an obtained object in each illumination interval, simultaneously timing by using a stopwatch, then forcibly scratching the edge of the cured part by adopting the tail part of a paper clip, inspecting whether a blank part of the edge of the cured part leaves a trace of the photocured substance or not until the cured part is completely cured, and measuring the speed of complete curing.

The following are the detection results:

the first embodiment is as follows:

component group	First portion of	The second part	Third part	Fourth part (C)	Fifth part (C)	Sixth part (C)	Seventh part (1)
								Illumination interval/nm	200-250	250-300	300-350	350-400	400-450	450-500	500-550
Percent curing/%)	100	100	100	100	100	100	100
								Curing time/s	11.3	9.6	9.8	9.2	9.5	10.3	11.1

Example two:

component group	First portion of	The second part	Third part	Fourth part (C)	Fifth part (C)	Sixth part (C)	Seventh part (1)
								Illumination interval/nm	200-250	250-300	300-350	350-400	400-450	450-500	500-550
Percent curing/%)	100	100	100	100	100	100	100
								Curing time/s	11.0	9.3	9.5	9.0	9.4	10.2	11.0

Example three:

component group	First portion of	The second part	Third part	Fourth part (C)	Fifth part (C)	Sixth part (C)	Seventh part (1)
								Illumination interval/nm	200-250	250-300	300-350	350-400	400-450	450-500	500-550
Percent curing/%)	100	100	100	100	100	100	100
								Curing time/s	10.8	9.1	9.2	8.8	9.2	10.1	10.9

Example four:

component group	First portion of	The second part	Third part	Fourth part (C)	Fifth part (C)	Sixth part (C)	Seventh part (1)
								Illumination interval/nm	200-250	250-300	300-350	350-400	400-450	450-500	500-550
Percent curing/%)	100	100	100	100	100	100	100
								Curing time/s	10.8	9.3	9.7	9.1	9.4	10.3	11.1

Example five:

component group	First portion of	The second part	Third part	Fourth part (C)	Fifth part (C)	Sixth part (C)	Seventh part (1)
								Illumination interval/nm	200-250	250-300	300-350	350-400	400-450	450-500	500-550
Percent curing/%)	100	100	100	100	100	100	100
								Curing time/s	10.4	9.1	9.6	9.0	9.4	10.3	11.1

Example six:

component group	First portion of	The second part	Third part	Fourth part (C)	Fifth part (C)	Sixth part (C)	Seventh part (1)
								Illumination interval/nm	200-250	250-300	300-350	350-400	400-450	450-500	500-550
Percent curing/%)	100	100	100	100	100	100	100
								Curing time/s	11.3	9.6	9.8	9.2	9.5	9.9	10.6

Example seven:

component group	First portion of	The second part	Third part	Fourth part (C)	Fifth part (C)	Sixth part (C)	Seventh part (1)
								Illumination interval/nm	200-250	250-300	300-350	350-400	400-450	450-500	500-550
Percent curing/%)	100	100	100	100	100	100	100
								Curing time/s	11.3	9.6	9.8	9.2	9.4	9.4	10.3

Comparative example one:

component group	First portion of	The second part	Third part	Fourth part (C)	Fifth part (C)	Sixth part (C)	Seventh part (1)
								Illumination interval/nm	200-250	250-300	300-350	350-400	400-450	450-500	500-550
Percent curing/%)	100	100	100	100	100	42	28
								Curing time/s	11.8	9.9	10.2	9.6	9.8	-	-

Comparative example two:

component group	First portion of	The second part	Third part	Fourth part (C)	Fifth part (C)	Sixth part (C)	Seventh part (1)
								Illumination interval/nm	200-250	250-300	300-350	350-400	400-450	450-500	500-550
Percent curing/%)	100	100	100	100	100	100	100
								Curing time/s	10.9	10.9	10.5	10.4	10.8	11.7	12.3

Comparative example three:

component group	First portion of	The second part	Third part	Fourth part (C)	Fifth part (C)	Sixth part (C)	Seventh part (1)
								Illumination interval/nm	200-250	250-300	300-350	350-400	400-450	450-500	500-550
Percent curing/%)	100	100	100	100	100	100	100
								Curing time/s	12.6	11.4	11.2	10.8	11.0	11.9	12.5

The result shows that the embodiment has larger acceptable illumination range, fast curing speed, better photoinitiation efficiency and larger application range compared with the comparative example.