JPS61118402A - Covering of solid substance with polymer - Google Patents

Abstract

PURPOSE:A liquid monomer, a polymerization initiator, and a solvent are allowed to adsorb on the surfaces of a solid substance, then the polymerization is carried out in a nondispersing agent to effect the uniform and firm covering of a solid substance in high efficiency. CONSTITUTION:A liquid monomer such as (meth)acrylic acid, acrylonitrile, or vinyl acetate, a polymerization initiator such as benzoyl peroxide, azobisisobutyronitrole and a solvent such as a hydrocarbon or alcohol areallowed to adsorb on the surfaces of a powdery, granular or fibrous solid substance such as silica gel, molecular sieves, activated carbon or alumina, then, the polymerization is effected on the surface in a non-dispersing agent, preferably for 1-5hr. USE:The products are used as a carrier for functional materials, forming materials or fillers.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of coating the surface of a solid material with a polymer. More specifically, the present invention relates to a method for uniformly, efficiently, and firmly coating the surface of a powdered, granular, or fibrous solid material with a polymer.

In recent years, composite materials of solid substances and polymers have been widely used in many fields as building materials and various materials, and have been gaining importance because they can be used as carriers for functional materials.

Generally, when manufacturing a composite material of a solid material and a polymer, the surface of the solid material undergoes a compositing process to form an interface between the matrix polymer and the solid material. The importance of this interface has been studied from various angles, and methods of modifying the physical and chemical structure of the surface of solid substances have already been attempted in order to obtain a desirable interface. For example, as a method for coating the surface of a solid substance with a polymer, solid particles are dispersed in a polymer solution, and a portion of the polymer is deposited on the particles by changing the polarity of the solution, and the monomer is dissolved. However, methods are known in which monomers and solid particles are dispersed in an organic solvent in which the polymer does not dissolve, and polymerization is carried out.

However, these methods have drawbacks such as low efficiency and easy peeling of the polymer due to collisions between solids or external forces, and have not yet reached a stage where they can be implemented industrially. In addition, the methods of bonding polymers to the solid surface through mechanochemical treatment or radiation treatment of the surface of the solid material have low efficiency, and their practical application to industry is technically and economically difficult. .

The present inventors have conducted extensive research to develop a method for uniformly and efficiently coating the surface of any solid substance with a polymer. The inventors discovered that by adsorbing polymers, polymerization initiators, and solvents, and then performing polymerization in a non-dispersing agent, the scales can be coated uniformly, efficiently, and firmly with polymers.Based on this knowledge, the present invention was completed. It's arrived.

That is, according to the present invention, a liquid monomer,
By adsorbing a polymerization initiator and a solvent, and then polymerizing directly on the surface of a solid substance without using a dispersant,
Polymer-coated solid materials can be easily obtained.

In order to suitably carry out the present invention, a liquid monomer, a polymerization initiator, and a solvent are adsorbed onto the surface of a solid substance, and then the liquid monomer, polymerization initiator, and solvent are placed in a sealable container, sealed, and adsorbed onto the solid substance at a predetermined temperature and for a predetermined time. The resulting monomers may be polymerized.

The solid substance used in the method of the present invention is preferably an inorganic or organic solid substance with a large surface area, such as silica gel, synthetic zeolite, natural zeolite, molecular sieves, alumina, carbon black, activated carbon, cellulose. Examples include. These may be used alone or in combination of two or more.

On the other hand, the monomer used in the method of the present invention is a liquid vinyl monomer that can undergo radical polymerization or radical copolymerization, such as acrylic acid, methacrylic acid, acrylic ester, and methacrylic acid. Examples include acid esters such as acrylonitrile, vinyl acetate, styrene, and divinylbenzene. These may be used in combination of two or more types.

Further, as the polymerization initiator used in the present invention, commonly known radical polymerization initiators can be advantageously used, and typical examples include benzylic peroxide, azobisisobutyronitrile, and potassium persulfate. can. The amount of initiator used is 0.1 relative to the amount of monomer used.
Approximately 10% by weight is appropriate.

Examples of the solvent used in the present invention include hydrocarbon water tJ
Examples include Ef, alcohols, ketones, ethers, and water. The type and amount of these solvents are selected and used depending on the monomer, polymerization initiator, and solid substance.

In the method of the present invention, these monomers, polymerization initiators, and solvents are adsorbed onto the surface of a solid substance by filtration. The amount of adsorption is controlled by the monomer concentration, type of solvent, etc.

The solid substance adsorbing the monomer, polymerization initiator, and solvent in this manner is left as it is, or is replaced with an inert gas such as nitrogen gas, the container is sealed, and the monomer is polymerized. Polymerization is carried out by standing still, but shaking may be performed if necessary. According to the present invention, most of the adsorbed monomer is polymerized in a polymerization time of about 1 to 5 hours, and the solid substance is uniformly and efficiently produced by the polymer, and most of the produced polymer is not extracted by the solvent. The more tightly the coating is applied.

The polymer-coated solid material obtained by the method of the present invention is
It can be used as a carrier for functional materials, and can be molded as it is, so it can be suitably used as a molding material, filling material, or filling material.

Furthermore, this method can be used as a surface treatment technique for pigments, etc., and is an extremely useful method industrially.

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

Example 1 Azobisisobutyronitrile (hereinafter abbreviated as AIBN) 0
．． Methyl methac VtV acid (hereinafter MMA
) 15gt1 Add 20 pieces of silica gel (made by Gyudon Kagaku, 10-40 mesh) to a mixed solution of 15ml of benzene.
g was immersed. Next, this was suction-filtered, placed in a pressure-resistant reaction tube, sealed, and left standing in a constant temperature bath at 80°C for 5 hours. After the reaction, the product was washed with ethyl ether 7 and
Polymer-coated silicage) v23.
I got 51. When this was observed with a scanning electron microscope,
It was found that the produced polymer uniformly and efficiently coated the surface of the silica gel particles.

As a result of subjecting the obtained polymer-coated silica gel to differential thermal analysis (hereinafter abbreviated as DTA-TGA), a weight loss of 14.9% and an accompanying exothermic peak of 373°C were observed. Also, this is 2. Of was weighed and immersed in 50ml of 40% hydrofluoric acid solution. As a result, 0.29f (14.5%
) polymethacrylic acid methacrylate/I/ (hereinafter abbreviated as PMMA) remained in the solution without being decomposed, indicating that the weight loss of TGA was due to the polymer component.

Example 2 In Example 1, various substances shown in Table 1 were used as the solid substance, monomer, and solvent, and the same operations as in Example 1 were performed. The state of polymer coating of the obtained polymer-coated solid materials was good.

The results are shown in Table 1.

Example 3 MMA39m in which 0.451 benzoyl peroxide was dissolved
20 f of synthetic zeolite (manufactured by Toyo Soda, type F9, 100 mesh or less) was immersed in a mixed solution of 10 ml of benzene. Next, this was filtered, then placed in a pressure-resistant reaction tube, sealed, and allowed to stand at 95° C. for 5 hours. After the reaction, the product was treated in the same manner as in Example 1 to obtain PM with good polymer coating.
MA-coated synthetic zeolite 2z9 was obtained.

As a result of subjecting this to DTA-TGA, a weight loss of 28.3% and accompanying exothermic peaks of 273°C and 353°C were observed.

The resulting PMMA-coated synthetic zeolite can be easily molded. Pressure 200 kg/cd, mold temperature 180°C
The bending strength of the molded product obtained by compression molding is 520 kg.
/cd, the compressive strength was 1.450 to 9/d.

Example 4 MM A 15 yx in which AIBNo, 6F was dissolved
l, divini lebenzene 0,5. /, benzene 15m
Silikage/v20f was immersed in a mixed solution of /. Next, after filtering this, put it in a pressure-resistant reaction tube and seal it.
It was left standing at 0°C for 5 hours. After the reaction, the reaction product was treated in the same manner as in Example 1 to obtain PMMA with good polymer coating.
A coated silica gel/L/22.4 g was obtained. As a result of subjecting this to TGA, a weight reduction of 14.1% was observed.

The resulting PMMA-coated silica gel 10f was added to 50ml of triethylenetetramine and reacted at 175°C for 5 hours to obtain product 10.59. When this product 1y was added to 500 ml of a solution with a hexavalent chromium concentration of 10 q/l, more than 99.9% of hexavalent chromium could be removed at pH 4 to 7.

Example 5 Polymer-coated solid material 1 obtained in Examples 1-2
When we weighed out 0 g and extracted it for a long time with a Soxhlet extraction device using benzene as a solvent, most of the polymer was not extracted, indicating that the polymer was integrated with the solid substance and tightly coated the surface. Ta. The results are shown in Table 1.

Comparative Example The solid substance used in Examples 1 and 2 was added to a solution of PMMAof dissolved in 100 t of benzene,
After stirring with a stirrer to uniformly disperse the mixture, a polymer-coated solid material was obtained by removing benzene while heating and degassing. When 1 of this was weighed and extracted with benzene according to Example 5, most of the polymer was easily extracted. The results are shown in Table 2.

Claims (1)

[Claims] When coating the surface of an inorganic or organic powdered, granular, or fibrous solid material with a polymer, a liquid monomer, a polymerization initiator, and a solvent are adsorbed onto the surface of the solid material, and then,
A method characterized by carrying out polymerization directly on the surface of a solid substance without using a dispersant.