阅读说明：本技术 一种利用长烷酸乙酯提高丙烯酸酯转子相光聚合转化率的方法 (Method for improving photopolymerization conversion rate of acrylate rotor phase by using ethyl alkanoate ) 是由 何勇 毛乔巧 姚淼 聂俊 于 2021-08-23 设计创作，主要内容包括：本发明属于光聚合技术领域,转子相链式光聚合属于特殊的一种固态聚合,它具有液态光聚合所不具有的固化收缩小,对氧气和水汽不敏感等优势,但是也存在缺陷。限制固态光聚合应用的一个最大问题就是聚合转化率较低。本发明采用掺杂长烷酸乙酯来促进长链丙烯酸酯单体的转子相链式光聚合反应,从而提高光聚合转化率,为研究这方面的转子相光聚合提供一定的参考价值。可用于一些对尺寸要求严格的特殊场合,例如在冬季甚至是极寒环境下室外材料的光聚合,精密光刻及图案化等领域。(The invention belongs to the technical field of photopolymerization, and rotor phase chain type photopolymerization belongs to special solid state polymerization, which has the advantages of small curing shrinkage, insensitivity to oxygen and water vapor and the like which are not possessed by liquid photopolymerization, but has defects. One of the biggest problems limiting the application of solid state photopolymerization is the low polymerization conversion. According to the invention, the rotor phase chain type photopolymerization reaction of the long-chain acrylate monomer is promoted by doping the ethyl alkanoate, so that the photopolymerization conversion rate is improved, and a certain reference value is provided for researching the rotor phase photopolymerization in the aspect. The method can be used in special occasions with strict requirements on the size, such as the fields of photopolymerization, precise photoetching, patterning and the like of outdoor materials in winter and even in extremely cold environments.)

1. The method for improving the photopolymerization conversion rate of the acrylate rotor phase by using the long-chain ethyl alkanoate is characterized in that the acrylate is one of tetradecyl acrylate, hexadecyl acrylate and octadecyl acrylate, and the long-chain ethyl alkanoate is one of pentadecanoic acid ethyl ester, hexadecyl acid ethyl ester, heptadecanoic acid ethyl ester, octadecanoic acid ethyl ester and nonadecanoic acid ethyl ester.

2. The method according to claim 1, wherein the photoinitiator is one of 2,4, 6-trimethylbenzoyl-diphenylphosphine oxide (TPO), ethyl 2,4, 6-trimethylbenzoylphosphonate (TPO-L), 2-hydroxy-methylphenylpropane-1-one (1173), 1-hydroxy-cyclohexyl-phenyl ketone (184), and benzil dimethyl ether (651).

3. The method according to claim 1, wherein the molar ratio of the acrylate to the ethyl alkanoate is 9:1-2:8, and the amount of the photoinitiator is 1% -6% of the mass sum of the long-chain acrylate and the long-chain alcohol.

Technical Field

The invention relates to the field of photocuring, in particular to photopolymerization of a long-chain organic alkene micromolecule and ethyl alkanoate mixed monomer system and influence of the mixed system on solid-state photopolymerization kinetics.

Background

Photopolymerization refers to the process of polymerizing monomers or liquid oligomers under the action of light (ultraviolet or visible light) to form polymers. The photopolymerization reaction has the advantages of high speed, mild conditions, less energy consumption and unique time and space controllability. When the illumination is started, the polymerization reaction occurs immediately, and after the illumination is stopped, the reaction is terminated immediately, so that the time can be controlled; when the covering mask is used for illumination, the part exposed to the light is polymerized, and the shielded part does not react, so that the space is controllable.

Because the traditional liquid photopolymerization has serious curing shrinkage and is easy to be inhibited by oxygen and water vapor, the application of the photopolymerization technology is restricted. Therefore, solving these problems is an important prerequisite for the development of photopolymerization technology. And because of the immature knowledge, the solid state polymerization cannot be realized, so that the photopolymerization reaction only focuses on the liquid state polymerization, and the solid state photopolymerization reaction is neglected.

The rotor phase is a special solid state in a special state of aggregation between fully ordered crystals and isotropic liquid. Recent research proves that rotor phase photopolymerization can occur in partial long-chain compounds, and the rotor phase photopolymerization has the advantages of small curing shrinkage, insensitivity to water vapor and the like which are not possessed by liquid photopolymerization, so that the application of solid photopolymerization is greatly expanded.

Previously, the literature reported tetradecyl acrylate and hexadecyl acrylate have a rotor phase, but the rotor phase is unstable and is susceptible to transformation into a crystalline phase. Although the reaction can occur at the polymerization temperature, the polymerization conversion rate is low, which greatly limits the application of the monomer in photopolymerization. In the patent, the long-chain ethyl alkanoate is introduced, so that the stability of a long-chain acrylate rotor phase is improved, the photopolymerization conversion rate is improved, and the application of solid photopolymerization, such as precision photoetching, patterning and the like, is widened.

Disclosure of Invention

The invention aims to research the photopolymerization kinetics of a blending system of acrylate and ethyl alkanoate so that the photopolymerization can be used in special occasions with strict requirements on the size, such as precision photoetching, patterning and the like.

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

the invention carries out rotor phase chain photopolymerization on acrylic ester, and the ethyl alkanoate monomer improves the property of a rotor phase and plays a role in improving the polymerization performance of the rotor phase. The photoinitiator is adopted as follows: 2,4, 6-trimethylbenzoyl-diphenylphosphine oxide (TPO), ethyl 2,4, 6-trimethylbenzoylphosphonate (TPO-L), 2-hydroxy-methylphenylpropane-1-one (1173), 1-hydroxy-cyclohexyl-phenyl ketone (184), benzil bismethyl ether (651).

The light source adopted by the invention is an LED lamp with main emission wavelength of 385 nm.

The experimental process of the invention is that the molar ratio of acrylate to ethyl alkanoate is 9:1-2:8, the dosage of the photoinitiator is 1% -6% of the mass sum of long-chain acrylate and long-chain alcohol, firstly, the mixture of two long-chain monomers is uniformly mixed, and the phase state transformation process of the blending system are researched by Differential Scanning Calorimetry (DSC). Then, uniformly mixing the binary mixture with 1-6% of photoinitiator by mass. And (3) placing the sample in a DSC sample chamber, and cooling by using a refrigerator. And after the temperature is constant, carrying out illumination polymerization by adopting an LED lamp light source.

The invention uses differential scanning calorimetry (Photo-DSC) to measure the photopolymerization conversion rate of the system in real time.

Drawings

FIG. 1: DSC images of different long-chain ethyl alkanoate and long-chain acrylate mixed systems.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Example 1

The octadecyl acrylate and 1 percent of photoinitiator TPO-L by mass are mixed evenly and loaded into a sample tray. The polymerization process was monitored by differential scanning calorimetry. Experimental conditions for the measurement of polymerization kinetics by differential scanning calorimetry: cooling to 10 deg.C at a rate of 2 deg.C/min, maintaining the temperature for 5min, and adopting a light intensity with a wavelength of 385nmIs 6mW/cm²Polymerization time of the LED lamp (1) is 15 min. The result of the differential scanning calorimetry shows that the photopolymerization conversion rate reaches 18 percent.

Example 2

Octadecyl acrylate and ethyl nonadecanoate were mixed in a molar ratio of 5:5, and the ternary mixture was uniformly mixed with 1% by mass of a photoinitiator TPO-L and loaded into a sample pan. The polymerization process was monitored by differential scanning calorimetry. Experimental conditions for the measurement of polymerization kinetics by differential scanning calorimetry: cooling to 10 deg.C at a rate of 2 deg.C/min, maintaining the temperature for 5min, and adopting a wavelength of 385nm and a light intensity of 6mW/cm²Polymerization time of the LED lamp (1) is 15 min. The result of the differential scanning calorimetry shows that the conversion rate of photopolymerization reaches 50 percent and is improved by 32 percent compared with the conversion rate of a simple octadecyl acrylate system.

Example 3

Octadecyl acrylate and ethyl nonadecanoate were mixed in a molar ratio of 3:7, and the ternary mixture was uniformly mixed with 1% by mass of a photoinitiator TPO-L and loaded into a sample pan. The polymerization process was monitored by differential scanning calorimetry. Experimental conditions for the measurement of polymerization kinetics by differential scanning calorimetry: cooling to 10 deg.C at a rate of 2 deg.C/min, maintaining the temperature for 5min, and adopting a wavelength of 385nm and a light intensity of 6mW/cm²Polymerization time of the LED lamp (1) is 15 min. The result of the differential scanning calorimetry shows that the conversion rate of photopolymerization reaches 53 percent and is improved by 35 percent compared with the conversion rate of a simple octadecyl acrylate system.

Example 4

Mixing octadecyl acrylate and ethyl heptadecanoate in a molar ratio of 5:5, uniformly mixing the ternary mixture with 1% by mass of photoinitiator TPO-L, and filling the mixture into a sample tray. The polymerization process was monitored by differential scanning calorimetry. Experimental conditions for the measurement of polymerization kinetics by differential scanning calorimetry: cooling to 10 deg.C at a rate of 2 deg.C/min, maintaining the temperature for 5min, and adopting a wavelength of 385nm and a light intensity of 6mW/cm²Polymerization time of the LED lamp (1) is 15 min. The result of the differential scanning calorimetry shows that the conversion rate of photopolymerization reaches 62 percent and is improved by 44 percent compared with the conversion rate of a simple octadecyl acrylate system.

Example 5

Cetyl acrylate and ethyl heptadecanoate were mixed in a molar ratio of 5:5, and the ternary mixture was then mixed uniformly with 1% by mass of photoinitiator TPO-L and loaded into a sample pan. The polymerization process was monitored by differential scanning calorimetry. Experimental conditions for the measurement of polymerization kinetics by differential scanning calorimetry: cooling to 0 deg.C at a rate of 2 deg.C/min, maintaining the temperature for 5min, and adopting a wavelength of 385nm and a light intensity of 6mW/cm²Polymerization time of the LED lamp (1) is 15 min. The result of the differential scanning calorimetry shows that the conversion rate of photopolymerization reaches 58 percent and is improved by 43 percent compared with the conversion rate of a simple system of cetyl acrylate.

Example 6

And mixing cetyl acrylate with 1 mass percent of photoinitiator TPO-L uniformly and then loading the mixture into a sample tray. The polymerization process was monitored by differential scanning calorimetry. Experimental conditions for the measurement of polymerization kinetics by differential scanning calorimetry: cooling to 0 deg.C at a rate of 2 deg.C/min, maintaining the temperature for 5min, and adopting a wavelength of 385nm and a light intensity of 6mW/cm²Polymerization time of the LED lamp (1) is 15 min. The result of the differential scanning calorimetry shows that the photopolymerization conversion rate reaches 15%.

Example 7

Cetyl acrylate and ethyl heptadecanoate were mixed in a molar ratio of 5:5, and the ternary mixture was then mixed uniformly with 3% by mass of photoinitiator TPO-L and loaded into a sample pan. The polymerization process was monitored by differential scanning calorimetry. Experimental conditions for the measurement of polymerization kinetics by differential scanning calorimetry: cooling to 0 deg.C at a rate of 2 deg.C/min, maintaining the temperature for 5min, and adopting a wavelength of 385nm and a light intensity of 6mW/cm²Polymerization time of the LED lamp (1) is 15 min. The result of the differential scanning calorimetry shows that the conversion rate of photopolymerization reaches 62 percent and is improved by 47 percent compared with the conversion rate of a simple system of cetyl acrylate.

Example 8

Tetradecyl acrylate and 1% of photoinitiator TPO-L by mass are uniformly mixed and loaded into a sample tray. The polymerization process was monitored by differential scanning calorimetry. Experimental conditions for the measurement of polymerization kinetics by differential scanning calorimetry: cooling to 0 deg.C at a rate of 2 deg.C/min, maintaining the temperature for 5min, and adopting a wavelength of 385nm and a light intensity of 6mW/cm²LED lampPolymerization time 15 min. The result of the differential scanning calorimetry shows that the photopolymerization conversion rate reaches 16%.

Example 9

Tetradecyl acrylate and ethyl heptadecanoate are mixed in a molar ratio of 5:5, and then the ternary mixture is uniformly mixed with 1% by mass of photoinitiator TPO-L and loaded into a sample tray. The polymerization process was monitored by differential scanning calorimetry. Experimental conditions for the measurement of polymerization kinetics by differential scanning calorimetry: cooling to 0 deg.C at a rate of 2 deg.C/min, maintaining the temperature for 5min, and adopting a wavelength of 385nm and a light intensity of 6mW/cm²Polymerization time of the LED lamp (1) is 15 min. The result of the differential scanning calorimetry shows that the conversion rate of photopolymerization reaches 63 percent and is improved by 47 percent compared with the conversion rate of a simple system of tetradecyl acrylate.