阅读说明：本技术 一种荧光功能单体、一种可及时发现涂布缺陷的压敏胶及其制备方法 (Fluorescent functional monomer, pressure-sensitive adhesive capable of timely discovering coating defects and preparation method thereof ) 是由 许显成 陈善勇 李坤 余孝其 程国虎 代申强 刘洋洋 于 2021-09-22 设计创作，主要内容包括：本发明公开了一种荧光功能单体、一种可及时发现涂布缺陷的压敏胶及其制备方法,属于功能涂层技术领域,本发明中的可及时发现涂布缺陷的压敏胶通过丙烯酸类单体与丙烯酸-萘二酰亚胺功能单体在溶剂中共聚而得；因高分子侧链上含有萘二酰亚胺荧光团,涂布后,经紫外-可见光照射,正常涂布区域有明亮的蓝色荧光,而漏涂区域无荧光,可快速观察到是否有漏涂区域,以便及时采取措施挽救,减少质量事故,大大提升产品良率。(The invention discloses a fluorescent functional monomer, a pressure-sensitive adhesive capable of timely finding coating defects and a preparation method thereof, belonging to the technical field of functional coatings, wherein the pressure-sensitive adhesive capable of timely finding coating defects is obtained by copolymerizing an acrylic monomer and an acrylic acid-naphthalimide functional monomer in a solvent; because the side chain of the polymer contains the naphthalimide fluorophore, after coating, the normal coating area has bright blue fluorescence through ultraviolet-visible light irradiation, and the coating omission area has no fluorescence, whether the coating omission area exists can be quickly observed, so that the method can be timely taken to save, reduce quality accidents and greatly improve the product yield.)

1. A fluorescent functional monomer is characterized in that the structural formula is as follows:

wherein n is a natural number of 1 to 8, R is an alkyl group, R is a hydroxyl group₁Is methyl or hydrogen.

2. The method for preparing fluorescent functional monomer according to claim 1, wherein the fluorescent functional monomer is prepared by nucleophilic substitution reaction of acryloyl chloride compound and aminoalkyl naphthalene diimide compound;

wherein, the structural general formula of the acryloyl chloride compound is shown as follows:

R₁is methyl or hydrogen;

the general structural formula of the aminoalkyl naphthalene diimide compound is shown as follows:

n is a natural number of 1 to 8, and R is an alkyl group.

3. The method for preparing the fluorescent functional monomer according to claim 2, which comprises the following steps: adding an aminoalkyl naphthalene diimide compound, alkali and a solvent into a reaction device, stirring and dissolving at the temperature of 0-5 ℃, then adding an acryloyl chloride compound in batches, stirring and reacting at room temperature for 1-3 hours after the materials are added, filtering, collecting filtrate, and removing the solvent to obtain a fluorescent functional monomer; wherein the molar ratio of the acryloyl chloride compound to the aminoalkyl naphthalene diimide compound to the alkali is 1:1: 1-2.

4. A pressure-sensitive adhesive capable of timely detecting coating defects, which comprises the fluorescent functional monomer according to claim 1.

5. The pressure-sensitive adhesive capable of timely finding coating defects as claimed in claim 4, characterized by comprising the following raw materials in parts by mass: 90-110 parts of acrylate monomer and 0.1-10 parts of fluorescent functional monomer.

6. The pressure-sensitive adhesive capable of timely finding coating defects as claimed in claim 4 or 5, characterized by comprising the following raw materials in parts by mass: 100 parts of acrylate monomers and 0.5-5 parts of fluorescent functional monomers.

7. The pressure-sensitive adhesive capable of timely detecting coating defects according to claim 6, wherein the acrylate monomer is at least one of acrylic acid, alkyl acrylate, methacrylic acid, alkyl methacrylate, hydroxyethyl acrylate and hydroxypropyl acrylate.

8. The pressure-sensitive adhesive capable of timely discovering coating defects according to claim 6, wherein the pressure-sensitive adhesive capable of timely discovering coating defects has the following characteristic structural components:

representing an acrylate macromolecular backbone

Wherein n is a natural number of 1 to 8, and R is an alkyl group.

9. The preparation method of the pressure-sensitive adhesive capable of timely discovering coating defects according to any one of claims 4 to 8, which is characterized by comprising the following steps:

step (1): stirring and dissolving an acrylate monomer, a fluorescent functional monomer, a free radical initiator and a solvent, wherein the free radical initiator accounts for 1-2% of the total mass of the acrylate monomer and the fluorescent functional monomer, and the solvent is at room temperature to obtain a polymerized monomer solution;

step (2): adding the polymerized monomer solution obtained in the step (1) of 1/4-1/3 into a polymerization reaction device, heating to 70-85 ℃ under the protection of inert gas, after the polymerization reaction is initiated, dropwise adding the residual polymerized monomer solution into a reaction system within 2-3 hours, continuing to perform heat preservation reaction for 4-5 hours, and cooling to obtain the pressure-sensitive adhesive capable of finding coating defects in time.

10. The method for preparing a pressure-sensitive adhesive capable of timely detecting coating defects according to claim 9, wherein the radical initiator is a peroxide initiator.

Technical Field

The invention relates to the technical field of functional coatings, in particular to a fluorescent functional monomer, a pressure-sensitive adhesive capable of timely finding coating defects and a preparation method thereof.

Background

Pressure-sensitive adhesive is widely applied in the processing and production processes of electronic products, and in order to reduce the use cost or reduce the emission to the environment, the coating amount of the pressure-sensitive adhesive, namely the coating thickness, needs to be reduced to prepare an ultrathin pressure-sensitive adhesive tape. When the pressure-sensitive adhesive is applied thinly, especially in the case of insufficient surface tension of the film, a region of the coating omission is easily generated, thereby causing a problem in product quality. And a method for rapidly detecting whether the pressure-sensitive adhesive is not coated is developed, so that the quality control is facilitated. When the pressure-sensitive adhesive contains fluorescent substances, after the pressure-sensitive adhesive is coated, the pressure-sensitive adhesive is irradiated by a proper light source, bright fluorescence is emitted from a coating area, and no fluorescence is emitted from a coating omission area, so that the pressure-sensitive adhesive can play a role in rapid and large-area detection. The fluorescent pressure-sensitive adhesive prepared by directly adding the fluorescent reagent into the pressure-sensitive adhesive through blending can theoretically play a role in fluorescence detection. However, in practice, after the pressure-sensitive adhesive blended with the fluorescent reagent is coated, the problems of fluorescent molecule migration, agglomeration and fluorescence quenching exist. In addition, the existing fluorescent monomer takes isolated double bonds to participate in copolymerization to obtain a fluorescent copolymer, but on one hand, isolated double bonds and conjugated double bonds have larger polarity difference, so that an ideal copolymer is difficult to form, and an alternating polymer fluorescent monomer is easy to form an alternating substance; meanwhile, due to the close proximity of the fluorescent probe, fluorescence quenching is easy to occur, and the brightness is reduced, and on the other hand, the problem of uneven distribution in a molecular chain also exists. Meanwhile, the stability and quantum efficiency of fluorescent molecules are all the problems that the design of the fluorescent pressure-sensitive adhesive must consider.

Disclosure of Invention

Aiming at the defects, the invention aims to provide a fluorescent functional monomer, a pressure-sensitive adhesive capable of timely finding coating defects and a preparation method thereof, which can effectively solve the problems of fluorescent molecular migration, agglomeration, fluorescent quenching and difficulty in forming an ideal copolymer by the fluorescent monomer in the prior art.

In order to achieve the purpose, the invention adopts the following technical scheme:

the invention provides a fluorescent functional monomer, which has the structural formula as follows:

wherein n is a natural number of 1-8, R is an alkyl group, R is a hydroxyl group₁Is methyl or hydrogen.

Further, R is methyl, ethyl, propyl or isopropyl.

The invention also provides a preparation method of the fluorescent functional monomer, which is prepared by carrying out nucleophilic substitution reaction on an acryloyl chloride compound and an aminoalkyl naphthalene diimide compound;

wherein, the structural general formula of the acryloyl chloride compound is shown as follows:

R₁is methyl or hydrogen;

the general structural formula of the aminoalkyl naphthalene diimide compound is shown as follows:

n is a natural number of 1 to 8, and R is an alkyl group.

Further, the preparation method of the fluorescent functional monomer specifically comprises the following steps:

adding an aminoalkyl naphthalene diimide compound, alkali and a solvent into a reaction device, stirring and dissolving at the temperature of 0-5 ℃, then adding an acryloyl chloride compound in batches, stirring and reacting at room temperature for 1-3 hours after the materials are added, filtering, collecting filtrate, and removing the solvent to obtain a fluorescent functional monomer; wherein the molar ratio of the acryloyl chloride compound to the aminoalkyl naphthalene diimide compound to the alkali is 1:1: 1-2.

Further, the molar ratio of the acryloyl chloride compound, the aminoalkyl naphthalene diimide compound and the alkali is 1:1: 1.2.

Further, the base is a carbonate salt, preferably sodium carbonate.

Further, the solvent is a conventional organic solvent, preferably ethyl acetate.

The invention also provides a pressure-sensitive adhesive capable of timely finding coating defects, which comprises the fluorescent functional monomer.

Further, the pressure-sensitive adhesive capable of timely finding coating defects comprises the following raw materials in parts by mass: 90-110 parts of acrylate monomer and 0.1-10 parts of fluorescent functional monomer.

Further, the pressure-sensitive adhesive capable of timely finding coating defects comprises the following raw materials in parts by mass: 100 parts of acrylate monomers and 0.5-5 parts of fluorescent functional monomers.

Further, the acrylate monomer is at least one of acrylic acid, alkyl acrylate, methacrylic acid, alkyl methacrylate, hydroxyethyl acrylate and hydroxypropyl acrylate.

Further, the alkyl group of the alkyl acrylate has an alkyl carbon chain number of 1 to 18, and the alkyl group may be a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a pentyl group, a hexyl group, a cyclohexyl group, a heptyl group, a 2-ethylhexyl group, an isooctyl group, a nonyl group, a decyl group, an isodecyl group, a dodecyl group, a tridecyl group, a tetradecyl group, a pentadecyl group, a hexadecyl group, a heptadecyl group or an octadecyl group.

Further, the pressure-sensitive adhesive capable of timely finding coating defects has the following characteristic structural components:

wherein n is a natural number from 1 to 8, and R is an alkyl group, preferably a methyl, ethyl, propyl or isopropyl group.

The invention also provides a preparation method of the pressure-sensitive adhesive capable of timely finding coating defects, which comprises the following steps:

step (1): stirring and dissolving an acrylate monomer, a fluorescent functional monomer, a free radical initiator and a solvent, wherein the free radical initiator accounts for 1-2% of the total mass of the acrylate monomer and the fluorescent functional monomer, and the solvent is at room temperature to obtain a polymerized monomer solution;

step (2): adding the polymerized monomer solution obtained in the step (1) of 1/4-1/3 into a polymerization reaction device, heating to 70-85 ℃ under the protection of inert gas, after the polymerization reaction is initiated, dropwise adding the residual polymerized monomer solution into a reaction system within 2-3 hours, continuing to perform heat preservation reaction for 4-5 hours, and cooling to obtain the pressure-sensitive adhesive capable of finding coating defects in time.

Further, the radical initiator is a peroxide initiator, preferably benzoyl peroxide.

Further, the solvent is ethyl acetate.

In summary, the invention has the following advantages:

1. compared with the conventional fluorescent monomer which is characterized by isolated double bonds, the double bonds of the fluorescent functional monomer are conjugated double bonds, and when the fluorescent functional monomer is copolymerized with an acrylate monomer, the polarity difference between the conjugated double bonds and the acrylate monomer is small, so that an ideal copolymer is easily formed, and the problems that an alternative polymer is easily formed and fluorescence quenching is easily generated during copolymerization of the conventional fluorescent monomer are effectively avoided.

2. The invention provides a pressure-sensitive adhesive capable of timely finding coating defects, which is obtained by copolymerizing an acrylic monomer and an acrylic acid-naphthalimide functional monomer in a solvent. Because the side chain of the polymer contains the naphthalimide fluorophore, after coating, the normal coating area has bright blue fluorescence through ultraviolet-visible light irradiation, and the coating omission area has no fluorescence, whether the coating omission area exists can be quickly observed, so that the method can be timely taken to save, reduce quality accidents and greatly improve the product yield.

3. The preparation method of the fluorescent functional monomer and the pressure-sensitive adhesive has the characteristics of simple operation, mild reaction conditions, easily obtained raw materials and the like, and has practical application value.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.

Thus, the following detailed description of the embodiments of the present invention is not intended to limit the scope of the invention as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

Preparation of acrylic acid-naphthalene diimide functional monomer 1 a:

0.256 g (10 mmol) of aminoalkylnaphthalene diimide 2a and 0.127 g (12 mmol) of anhydrous Na₂CO₃Adding the mixture into 200 ml of ethyl acetate, cooling the mixture to 0-5 ℃ in an ice water bath, stirring the mixture, adding 0.090 g (10 mmol) of acryloyl chloride in batches within 1 hour, continuing stirring the mixture at room temperature for reacting for 2 hours, filtering the mixture, collecting filtrate, and evaporating the solvent to obtain 0.3 g of acrylic acid-naphthalimide functional monomer 1 a.

Preparing a pressure-sensitive adhesive: dissolving 5 parts by weight of acrylic acid, 25 parts by weight of butyl acrylate, 70 parts by weight of isooctyl acrylate, 1 part by weight of acrylic acid-naphthalimide functional monomer 1a and 1.1 part by weight of benzoyl peroxide free radical initiator in 100 parts by weight of ethyl acetate to prepare a polymerization monomer solution; one third of the polymerization monomer solution is added into a reaction vessel equipped with a stirring, constant pressure dropping funnel and a nitrogen draft tube at one time, the temperature is raised to 75 ℃, the reaction initiation is waited, and after the reaction is successfully initiated, the residual two thirds of the monomer solution are dropped within 2 hours. And then continuously preserving the heat, stirring for reacting for 4 hours, and cooling to obtain the pressure-sensitive adhesive capable of timely finding coating defects.

After the pressure-sensitive adhesive prepared by the embodiment is coated, the normal coating area has bright blue fluorescence after being irradiated by ultraviolet-visible light, and the missing coating area has no fluorescence, so that whether the missing coating area exists or not can be quickly observed.

Example 2

Preparation of acrylic acid-naphthalene diimide functional monomer 1 b:

0.284 g (10 mmol) of aminoalkylnaphthalene diimide 2b and 0.127 g (12 mmol) of anhydrous Na were added₂CO₃Adding the mixture into 200 ml of ethyl acetate, cooling the mixture to 0-5 ℃ in an ice water bath, stirring the mixture, adding 0.090 g (10 mmol) of acryloyl chloride in batches within 1 hour, continuing stirring the mixture at room temperature for reacting for 2 hours, filtering the mixture, collecting filtrate, and evaporating the solvent to obtain 0.31 g of acrylic acid-naphthalimide functional monomer 1 b.

Preparing a pressure-sensitive adhesive: dissolving 1 part by weight of acrylic acid, 4 parts by weight of hydroxyethyl acrylate, 25 parts by weight of butyl acrylate, 70 parts by weight of isooctyl acrylate, 0.5 part by weight of acrylic acid-naphthalimide functional monomer 1b and 1 part by weight of benzoyl peroxide free radical initiator in 100 parts by weight of ethyl acetate to prepare a polymerization monomer solution; one third of the polymerization monomer solution is added into a reaction vessel equipped with a stirring, constant pressure dropping funnel and a nitrogen draft tube at one time, the temperature is raised to 75 ℃, the reaction initiation is waited, and after the reaction is successfully initiated, the residual two thirds of the monomer solution are dropped within 2 hours. And then continuously preserving the heat, stirring for reacting for 4 hours, and cooling to obtain the pressure-sensitive adhesive capable of timely finding coating defects.

After the pressure-sensitive adhesive prepared by the embodiment is coated, the normal coating area has bright blue fluorescence after being irradiated by ultraviolet-visible light, and the missing coating area has no fluorescence, so that whether the missing coating area exists or not can be quickly observed.

Example 3

Preparation of acrylic acid-naphthalene diimide functional monomer 1 c:

0.284 g (10 mmol) of aminoalkylnaphthalene diimide 2b and 0.127 g (12 mmol) of anhydrous Na were added₂CO₃Adding the mixture into 200 ml of ethyl acetate, cooling the mixture to 0-5 ℃ in an ice water bath, stirring the mixture, adding 0.104 g (10 mmol) of methacrylic chloride in batches within 1 hour, continuing stirring the mixture at room temperature for reacting for 2 hours, filtering the mixture, collecting filtrate, and distilling off the solvent to obtain 0.32 g of acrylic acid-naphthalimide functional monomer 1 c.

Preparing a pressure-sensitive adhesive: dissolving 1 part by weight of acrylic acid, 5 parts by weight of hydroxypropyl acrylate, 24 parts by weight of butyl acrylate, 70 parts by weight of isooctyl acrylate, 2 parts by weight of acrylic acid-naphthalimide functional monomer 1c and 1 part by weight of peroxy-azo-diisobutyl radical initiator in 100 parts by weight of ethyl acetate to prepare a polymerization monomer solution; one third of the polymerization monomer solution is added into a reaction vessel equipped with a stirring, constant pressure dropping funnel and a nitrogen draft tube at one time, the temperature is raised to 75 ℃, the reaction initiation is waited, and after the reaction is successfully initiated, the residual two thirds of the monomer solution are dropped within 2 hours. And then continuously preserving the heat, stirring for reacting for 4 hours, and cooling to obtain the pressure-sensitive adhesive capable of timely finding coating defects.

After the pressure-sensitive adhesive prepared by the embodiment is coated, the normal coating area has bright blue fluorescence after being irradiated by ultraviolet-visible light, and the missing coating area has no fluorescence, so that whether the missing coating area exists or not can be quickly observed.

Example 4

Preparation of acrylic acid-naphthalene diimide functional monomer 1 d:

0.298 g (10 mmol) of aminoalkylnaphthalene diimide 2c and 0.127 g (12 mmol) of anhydrous Na₂CO₃Adding the mixture into 200 ml of ethyl acetate, cooling the mixture to 0-5 ℃ in an ice water bath, stirring the mixture, adding 0.090 g (10 mmol) of acryloyl chloride in batches within 1 hour, continuing stirring the mixture at room temperature for reacting for 2 hours, filtering the mixture, collecting filtrate, and evaporating the solvent to obtain 0.32 g of acrylic acid-naphthalimide functional monomer 1 d.

Preparing a pressure-sensitive adhesive: dissolving 1 part by weight of acrylic acid, 4 parts by weight of hydroxyethyl acrylate, 25 parts by weight of butyl acrylate, 70 parts by weight of isooctyl acrylate, 3 parts by weight of acrylic acid-naphthalimide functional monomer 1d and 1 part by weight of peroxy-azo-diisobutyl radical initiator in 100 parts by weight of ethyl acetate to prepare a polymerization monomer solution; one third of the polymerization monomer solution is added into a reaction vessel equipped with a stirring, constant pressure dropping funnel and a nitrogen draft tube at one time, the temperature is raised to 75 ℃, the reaction initiation is waited, and after the reaction is successfully initiated, the residual two thirds of the monomer solution are dropped within 2 hours. And then continuously preserving the heat, stirring for reacting for 4 hours, and cooling to obtain the pressure-sensitive adhesive capable of timely finding coating defects.

After the pressure-sensitive adhesive prepared by the embodiment is coated, the normal coating area has bright blue fluorescence after being irradiated by ultraviolet-visible light, and the missing coating area has no fluorescence, so that whether the missing coating area exists or not can be quickly observed.

Example 5

This example differs from example 1 only in that: the mass portion of the acrylic acid-naphthalimide functional monomer 1a is adjusted to 0.1 portion, and the rest steps and parameters are the same.

After the pressure-sensitive adhesive prepared by the embodiment is coated, the normal coating area has bright blue fluorescence after being irradiated by ultraviolet-visible light, and the missing coating area has no fluorescence, so that whether the missing coating area exists or not can be quickly observed.

Example 6

This example differs from example 1 only in that: the mass portion of the acrylic acid-naphthalimide functional monomer 1a is adjusted to 10 portions, and the rest steps and parameters are the same.

After the pressure-sensitive adhesive prepared by the embodiment is coated, the normal coating area has bright blue fluorescence after being irradiated by ultraviolet-visible light, and the missing coating area has no fluorescence, so that whether the missing coating area exists or not can be quickly observed.

Comparative example 1

This example provides a fluorescent pressure-sensitive adhesive which differs from the preparation of the pressure-sensitive adhesive of example 1 only in that: replacing the acrylic acid-naphthalimide functional monomer 1a with a fluorescent functional monomer A, wherein the rest steps and parameters are the same; wherein, the structural formula of the fluorescent functional monomer A is shown as follows:

the fluorescent pressure-sensitive adhesive prepared by the embodiment has the advantages that after ultraviolet-visible light irradiation, the color development of a normal coating area is very weak, the color difference with a missing coating area is not obvious, and whether the missing coating area exists or not can not be quickly observed due to the fact that the fluorescent functional monomer A is easy to form an alternative polymer.

Comparative example 2

This example provides a fluorescent pressure-sensitive adhesive which differs from the preparation of the pressure-sensitive adhesive of example 1 only in that: replacing the acrylic acid-naphthalimide functional monomer 1a with a fluorescent functional monomer B, wherein the rest steps and parameters are the same; wherein, the structural formula of the fluorescent functional monomer B is shown as follows:

the fluorescent pressure-sensitive adhesive prepared by the embodiment has extremely weak color development of a normal coating area and unobvious color difference with a missing coating area after ultraviolet-visible light irradiation because the fluorescent functional monomer B is easy to form an alternative polymer, and whether the missing coating area exists cannot be quickly observed.

The foregoing is merely exemplary and illustrative of the present invention and it is within the purview of one skilled in the art to modify or supplement the embodiments described or to substitute similar ones without the exercise of inventive faculty, and still fall within the scope of the claims.