JPS60199003A - Photosensitive high polymer and preparation thereof - Google Patents

Abstract

PURPOSE:To obtain a novel substance useful as a photosensitizer in a system for converting solar light energy into chemical energy for storage utilizing photoisomerization reaction of a photochemical thermal energy storage material, by graft copolymerizing chloromethylstyrene with a porous or fibrous high polymer, and condensing the graft copolymer with a keto-carboxylic acid, etc. CONSTITUTION:An insoluble high polymer, obtained by graft copolymerizing chloromethylstyrene with a porous or fibrous high polymer, e.g. polyethylene, activated carbon, vinyl fibers or asbestos treated to give a large surface, and condensing the resultant copolymer with a keto-carboxylic acid, e.g. acetylbenzoic acid, or a keto-alcohol, e.g. acetone alcohol or benzoylacetone, and having the keto-carboxylic acid residue or keto-alcohol residue linked through methylene bonds to the benzene skeleton of the styrene based polymer.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a novel photosensitizing polymeric substance and a method for producing the same. More specifically, the present invention utilizes a photoisomerization reaction of a so-called photochemical heat storage material to convert sunlight energy into chemical energy. The present invention relates to an insoluble photosensitizing polymer substance that can be effectively used as a photosensitizer in a storage system, and a method for producing the same.

In recent years, with the depletion of petroleum resources, research on the use of solar energy as an alternative energy source has been actively conducted. A system that converts energy into a high-energy isomer, stores it, and returns it to the original substance when necessary through a dark reaction using a catalyst, while at the same time dissipating the accumulated energy as heat and using it for heating, etc. , which is attracting attention at home and abroad as an economically promising system for utilizing solar energy.

An outline of the system is shown in the attached drawing. The figure is a schematic diagram of a solar energy conversion system using a photochemical heat storage material, and 1 in the figure shows a photoisomerization reaction by irradiating the photochemical heat storage material with sunlight. 2 and 2' are circulation pumps, 3 is a storage tank for storing high-energy isomers converted by photoisomerization reaction, and 3' is a storage tank for storing high-energy isomers converted to original substances by dark reaction. The storage tank 4 is an exothermic reaction tank for dissipating the energy of the high-energy isomer as heat and returning the isomer to its original substance.

Examples of the photochemical heat storage material used in this system include norbornadiene and stilbene. However, many of these photochemical heat storage materials are colorless and transparent substances that do not absorb in the ultraviolet and visible wavelength ranges of sunlight, so they usually do not cause isomerization reactions due to sunlight as they are. First, only side reactions such as polymerization reactions proceed. Therefore, in order to cause a photochemical heat storage material to undergo a photoisomerization reaction and convert it into a high-energy isomer, it is necessary to have the ability to absorb light and transfer that energy to the photochemical heat storage material instead of the photochemical heat storage material. It is necessary to add a photosensitizer.

Regarding this photosensitizer, it is desirable not to mix it into the storage tank or exothermic reaction tank in order to avoid deactivation due to contamination of the catalyst used in the dark reaction, and also from the point of view of economic efficiency in repeated operation of the system. A material that is insoluble and can be fixed in the light irradiation chamber is required.

However, conventional photosensitizers have not always been able to satisfy these demands.

In order to meet the above-mentioned demands, the present inventors have conducted extensive research into photosensitizers used in systems that convert and store solar energy into chemical energy by utilizing the photoisomerization reaction of photochemical heat storage materials. As a result of repeated efforts, it was discovered that an insoluble photosensitizing polymer substance having a specific structure is suitable for the purpose, and based on this knowledge, the present invention was completed.

That is, the present invention provides a method in which a ketocarboxylic acid residue or a ketoalcohol residue is bonded to the benzene skeleton of a styrenic polymer obtained by graft polymerization to a porous or fibrous organic or inorganic polymer substance through a methylene bond. Insoluble photosensitizing polymeric substances and porous or fibrous organic or inorganic polymeric substances are graft-polymerized with chloromethylstyrene, and then ketocarboxylic acids or ketoalcohols are condensed thereto. A method for producing a photosensitizing polymeric substance is provided.

Regarding the porous or fibrous organic or inorganic polymer material used in the present invention, first, as the porous organic polymer material, for example, commercially available adsorption polystyrene-based, polyacrylic acid ester-based MR resin with a large surface area, polyethylene Examples include general-purpose resins such as polypropylene treated to increase surface area. Examples of porous inorganic polymer substances include activated carbon, silica gel, zeolite, alumina, coarse particles such as various calcium silicates and aluminum silicates, and fired products such as glass and bricks. Furthermore, examples of the fibrous organic polymer material include organic fibers such as cellulose fibers, vinyl fibers, and acrylic fibers, and examples of the fibrous inorganic polymer material include asbestos and carbon fiber.

In the present invention, the chloromethylstyrene to be graft-polymerized to the above-mentioned polymeric substance may be a commercially available m-1p-mixture, and in the liquid phase grafting method, it can be used as it is or as a benzene solution of an appropriate concentration. Furthermore, in the gas phase grafting method, it is usually used in an undiluted state. The graft polymerization reaction may be carried out using a peroxide catalyst, a cerium salt, or the like, or by irradiation with active light such as gamma rays, electron beams, and ultraviolet rays. In the case of this irradiation method, a simultaneous irradiation method or a pre-irradiation method may be used.

In the liquid phase grafting method, the polymerization reaction proceeds in air, in an inert atmosphere, or under reduced pressure, but in the gas phase grafting method, it is desirable to irradiate the active light under reduced pressure. The grafting ratio is generally higher in the liquid phase grafting method, but in the gas phase grafting method, the degree of decrease in surface area after the reaction is low, a uniform grafted product can be obtained, and there is also less by-product homopolymer. High monomer usage efficiency. Note that when graft polymerizing an inorganic polymer substance, it is desirable to add an appropriate unsaturated silane camping agent or the like.

In the present invention, a ketocarboxylic acid or a ketoalcohol is used to introduce a carbonyl functional group exhibiting photosensitivity. Ketocarboxylic acids include, for example, aliphatic carbonyl-substituted carboxylic acids such as acetylbenzoic acid;
Any aromatic carbonyl-substituted carboxylic acid such as benzoylbenzoic acid can be used. Examples of keto alcohols include acetone alcohol, diacetone alcohol, and acetylacetone and benzoylacetone, which can be converted into alcohol forms due to tautomerism.

The condensation reaction in the present invention is carried out by adding the grafted polymer, a ketocarboxylic acid or ketoalcohol in excess of the theoretical amount, an acetonate salt, etc. to a solvent insoluble to the grafted polymer, such as dimethylformamide or benzene. , by heating while stirring. The reaction temperature is usually in the range of room temperature to ZooC, and the reaction time is about 1 to 24 hours. In this condensation reaction, it is desirable to add a small amount of low molecular weight amine in order to facilitate dehydrochlorination.

Furthermore, when using a keto alcohol, it may be advantageous to use its sodium salt or sodium alcoholade. After the condensation reaction is completed, the desired photosensitized polymer substance is obtained by washing with an inert solvent such as dimethylformamide, benzene, chloroform, methanol, etc. and drying.

The photosensitizing polymer material obtained in this way is attached to the benzene skeleton of a styrenic polymer obtained by graft polymerization to a porous or fibrous organic or inorganic polymer material through a methylene bond. It is an insoluble material into which sensitive ketocarboxylic acid residues or ketoalcohol residues have been introduced, and a small amount of it is mixed into a photochemical heat storage material such as all-norbornadiene and irradiated with light while stirring or irradiated with light while immersed. By carrying out this process, the photochemical heat storage material can be photoisomerized into a high-energy substance such as quadruple crane, and the purpose of heat storage by chemical conversion of light energy can be achieved.

The insoluble photosensitizing polymeric substance of the present invention can be used, for example, in a light irradiation room as a photosensitizer in a system that replaces and stores sunlight energy with chemical energy by utilizing the photoisomerization reaction of a photochemical heat storage material. It can be used in a fixed manner and has extremely high practical value.

Next, the present invention will be explained in more detail with reference to Examples.

Example 1 High density polyethylene pellets 25ri xylene 500-
The mixture was heated for 2 hours with stirring to dissolve the mixture, and after cooling, the resulting gel was separated by a suitable filtration method. This product was immersed in flt methanol to be dispersed, filtered twice, dried in air at 40°C, and crushed to obtain coarse granular porous polyethylene. The surface area of this thing is 11.2rr? /f.

Next, the coarse-grained porous polyethylene 10.066 F obtained in this way was placed in a test tube with a ground lid having a diameter of 491 m1, and purified by distillation. Styrene mixture) 10
- and 50 mef of benzene were added, and while evacuated using liquid nitrogen, the product was deoxidized by repeated cooling, solidification, and melting and degassing.The test tube was attached to the top of the lid and irradiated with gamma rays at room temperature for 117 hours to remove the product. After suction filtration, it was washed repeatedly with benzene, air-dried in the air, and then dried under reduced pressure. Yield i is 11.
At 932 f, the graft ratio (polyethylene weight with weight increase of 7 yuan) was 0.185. In this product, the presence of significant at was confirmed by qualitative tests, and grafting was confirmed by infrared absorption spectrum.

To this kraft polyethylene 0.9939, 0.917 V of 4-acetylbenzoic acid, 75 m of triethylamine Q, and 50 m of dinotylformamide, which corresponds to 5 times the theoretical amount of grafted chloromethylstyrene groups]
Add 1 and heat for 2 hours while stirring on a boiling water bath.
I installed it at night. Next, the entire product was filtered off, washed with warm dimethylformamide, water, and chloroform, and then dried under reduced pressure. Yield showed 8.07% weight gain at 1.073F. It was confirmed by infrared absorption spectrum that 4-acetylbenzoic acid was bound to this product. The substitution rate of chloromethylstyrene was 61.7%.

Example 2 To the coarse chloromethylstyrene kraft polyethylene particles prepared in Example 1, 1.505 F of O-benzoylbenzoic acid, which is equivalent to about 5 theoretical times the chlorine content, was added, triethylamine 0.75+d, and dimethylformamide 50 F.
+d and heated at 95° C. for 2 hours with stirring, and then left overnight.

The product was then filtered, washed with hot dimethylformamide and chloroform, and dried under reduced pressure. The yield was 10.7% weight gain at 124f. The substitution rate of chloromethylstyrene was 54.8%.

Example 3 252 grams of acetylacetone was poured into a mixed solution of 112 grams of sodium hydroxide, 15 grams of water, and 50 grams of methanol, and after cooling, the mixture was separated, washed with a small amount of methanol, and dried to obtain sodium acetylacetonate.

Next, the aforementioned sodium acetylacetonate 0.634? (approximately 5 times the theoretical amount of chlorine content) was added, and the mixture was heated with dimethyl sulfoxide 40°C in a water bath at 55°C for approximately 27 hours with stirring. After cooling, the product was filtered, thoroughly washed with methanol, dried by heating in an air bath, and further dried under reduced pressure. It was confirmed from the absorption spectrum that it was acetylacetonated.

Example 4 Chloromethylstyrene kraft polyethylene coarse particles prepared in Example 1 0.30 (0,5 liters of acetylacetone)
ml, triethylamine 0.3 ml, and dimethylformamide 20-ml were added thereto, and the mixture was heated on a boiling water bath for 2 hours with stirring to react. After cooling, the mixture was washed with dimethylformamide and chloroform to obtain a white powdery polymer. It was confirmed from the infrared absorption spectrum of the product that acetylacetone was bound.

Examples 5 to 1O Dichloromethylstyrene was graft-polymerized to various forms of organic and inorganic polymeric substances by gamma ray irradiation in the same manner as in Example 1. The results are shown in the table below.

All of these graft compositions were able to be made into photosensitized polymeric substances by a method similar to Examples 1 to 4.

Application Example J: A norbornadiene-cyclohexane solution with a concentration of mol/3.0 was placed in a 1 m square, 5 m high light irradiation tube made of transparent quartz, and the 4-acetylbenzoic acid obtained in Example 1 was bound to this. Add 10.3μ of chloromethylstyrene kraft polyethylene powder, stir the inside of the tube with a small magnetic stirrer, and add 340n of spectroscopic
The product was irradiated with m light (intensity 1.OX 1105er/5ecd) at room temperature for 1.5 to 15 hours, and the production rate of quadricyclene was determined by gas chromatography. As a result, it reached 4.6% after 15 hours of irradiation.

In addition, the chloromethylstyrene grafted polyethylene bonded with 0-benzoylbenzoic acid prepared in Example 2 was
When used in the same manner as above, the quadricyclene conversion rate was 5.9%.

[Brief explanation of drawings]

The figure is a schematic diagram of a solar energy conversion system using photochemical heat storage materials.
is a circulation pump, 3.3' is a storage tank, and 4 is an exothermic reaction tank.

Claims (1)

[Claims] ■ A ketocarboxylic acid residue or ketoalcohol residue is bonded to the benzene skeleton of a styrenic polymer obtained by graft polymerization to a porous or fibrous organic or inorganic polymer substance via a methylene bond. An insoluble photosensitizing polymer substance. 2. A method for producing an insoluble photosensitizing polymeric material, which comprises graft polymerizing chloromethylstyrene onto a porous or fibrous organic or inorganic polymeric material, and then condensing the same with a ketocarboxylic acid or ketoalcohol. .