JPS61106603A - Production of gel - Google Patents

Abstract

PURPOSE:To obtain a hydrated polymer gel which is elastic and resistant to deformation, by polymerizing an aqueous polymerizable monomer solution comprising a water-soluble vinyl compound and a hydrophilic medium in a synthetic resin vessel. CONSTITUTION:An aqueous polymerizable monomer solution comprising a water-soluble vinyl compound and a hydrophilic medium as essential components and about 20wt% or below other copolymerizable vinyl compounds is polymerized in a synthetic resin vessel. Examples of the polymerizable water-soluble monomers include acrylic acid, methacrylic acid, alkali metal acrylates and alkali metal methacrylates. When the water-soluble monomer is used at a concentration of about 3-30wt%, the effect is stable. When the vinyl compound is used in an amount of, usually, about 0.1-20wt%, based on the water-soluble monomer, a good result can be obtained.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention involves charging a monomer mixture with a predetermined composition into a container that has been shaped into a desired shape, polymerizing it there, and subjecting it to some external pressure. The present invention relates to a method for producing a gel body that can continue to exhibit elasticity without breaking even when exposed to strong winds.

[Prior art] - Mixing poly(meth)acrylic acid, CMCs polyvinyl alcohol, hydroxyethyl cellulose, gelatin, polyvinylpyrrolidone, starch, grafted starch, etc. with drugs, fragrances, humectants, etc. and using it as a water-retentive gel. is well done.

Specific uses include, for example, base materials for ointments and patches, toothpastes, and base materials for certain types of cosmetics.

Separately, polymerizable monomers are polymerized to create polymers that are partially crosslinked using crosslinkable monomers, and water-retentive properties are added to make them into sip materials for electric law and facial packs. A wide variety of applications are being considered, including as wood and fragrance preservation material.

[Problem that the invention seeks to solve]

However, the polymers used for these purposes deform even when subjected to relatively small stress, and this deformation does not reverse even when the stress is removed, resulting in so-called permanent deformation. It could not be used in situations where it would be more convenient to use it while maintaining its shape. □"・1 Avoid such inconveniences Even if you try to store it in a narrow tube or a container with a complicated shape, it is difficult to mechanically fill it because of its high viscosity or because it is a gel. It was difficult to do so.

[Means for solving problems]

The present invention consists of a gel body that can absorb stress and maintain its shape with appropriate elasticity without breaking even when subjected to some external pressure, and a gel body that is shaped into an object with a more complex shape. We have arrived at this after conducting various studies to provide a similar function to the material, which contains a water-soluble vinyl compound and a hydrophilic medium as essential components, and contains approximately 20% by weight or less of other copolymerizable vinyl compounds. The present invention relates to a method for producing a gel body of a water-containing polymer that exhibits elasticity and is resistant to deformation by polymerizing the aqueous solution of the polymerizable monomer in a synthetic resin container.

[Effect]

The polymerizable water-soluble monomers used in the present invention include acrylic acid, methacrylic acid, alkali metal salts of acrylic acid,
One or more selected from the group of alkali metal salts of methacrylic acid are used.

In addition, as a vinyl compound that can be copolymerized with the above-mentioned water-soluble monomer and within a range that does not impair the function of the resulting gel body, for example, a vinyl compound selected from the following group may be used.

That is, polyvalent metal salts of acrylic acid and methacrylic acid (salt-forming cations include calcium, magnesium, aluminum, iron, manganese, zinc, barium, etc.)
, divinylbenzene, ethylene glycol diacrylate, polyethylene glycol diacrylate, polyvalent allyl sugar ale, NUN'-methylene bis(meth)
Acrylamide, 1,3-di(acrylamidomethyl)
-2-imidazolitone, 1,3-di(methacrylamidomethyl)-2-imidazolitone, diacrylamide methylethylene urea, diacrylamide dimethyl ether, and the like.

Other (meth)acrylic acid esters, (meth)acrylic acid alkoxyalkyl esters, (meth)acrylic acid hydroxyalkyl esters, vinyl acetate, styrene, acrylonitrile, acrylamide, vinyl carbazole, maleic anhydride, or their homologs or derivatives are also available. One or more of the above-mentioned materials can be used as necessary.

Although the water-soluble monomer cannot be uniformly determined depending on the degree of polymerization of the desired polymer, stable effects can be expected when used at a concentration of approximately 3 to 30% by weight. If a concentration smaller than this range is used, the resulting gel body cannot be expected to have the desired mechanical strength, while if it is too large, the hardness tends to be excessively high.

The vinyl compound has a ratio of about 0.0% to the water-soluble monomer.
An amount equivalent to 1 to 20 weights is used. Although this range is not necessarily uniform depending on the degree of polymerization of the finally obtained polymer, it exhibits the desired effect for normal uses.

The polymerization uses polymerization initiators such as cumene hydroperoxide (CHP), potassium persulfate (KPS), ammonium persulfate (APS), hydrogen peroxide, etc. in a conventional aqueous medium, but also 2.2'- It goes without saying that a water-soluble azo initiator such as (amidinopropane) hydrochloride, an ionic initiator, or a dox initiator can be used.

In the present invention, a gel body is formed by polymerizing the above-mentioned polymer components, and one feature lies in the place where the polymerization is performed. That is, the monomer formulation prepared for the above-mentioned polymerization is prepared in advance by using a polymerization vessel that has been shaped so as to directly form the final product form, and when separated from the polymerization vessel, the it product is The point is to use it as a.

The polymerization vessels used for this purpose are most commonly made of polyethylene, polypropylene or polyvinyl chloride, but may also be made of films such as polyamide, polyester, Surlyn A or cellophane, or of these materials. A film provided with another synthetic resin layer may also be used. In addition, thick-walled pipes, tubes, etc. that do not fit into the concept of film may be modified.
It is also possible to carry out *Running A1 sufficiently.

〔Example〕

The present invention will be specifically explained below by way of Examples.

Example 1 Sodium methacrylate 24.0 parts by weight Calcium acrylate 12.0 #Divinylbenzene
2. OI Acrylonitrile 2. OI Ethylenone Recall 5. OI Water 50.0 Place the blend in 1 into a polyethylene cylindrical bag with a diameter of 10 cIn and a length of 30 cm, 2 parts of water with APS O, 0.06 parts by weight and 3 parts of water with nitrilotrispropionamide 0
．． 014 parts by weight were quickly added and mixed, and after performing N2 substitution, the opening was tightened.
It was maintained at 30°C. After about 9 minutes, an increase in internal temperature was observed,
The maximum temperature was reached after about 1 hour.

The obtained polymer has moderate hardness and does not undergo flow deformation.
7″ stable, 1 also 0″’C 1・1
Example 2 Sodium methacrylate 25.0 Magnesium acrylate 5.0 Polyethylene glycol diacrylate 1.02 and Droxyethyl acrylate 10.0 Ethylene glycol 30
．． 0 water 2
2.2'-(2-amidinopropane) in the c10 formulation
After mixing 0.01 part by weight of hydrochloride and quickly homogenizing it, the air in the cavity was collected into a soft vinyl chloride tube (one end is closed) with an inner diameter of 10 mm and an outer diameter of 14 m. After substitution, polymerization was carried out. The polymerization behavior followed the same process as in Example 1. In this way, the Tokuten Gel Taijin Stew was cut into 20-length pieces, connected in the shape of a blind, and then used as the underlay of a household juicer mixer. When I was there, Mitsuhide was able to absorb the vibrations.

Example 3 Sodium acrylate 12.0 Magnesium acrylate 1.2 Ethylene glycol
12.0 Polyethylene glycol diacrylate 0.3 Water
74.5 APS
α04 Sodium sulfite
15X28X4cI mixture according to α02 formulation
Put it in an IL polyvinyl chloride resin film bag and say N! After substitution, polymerization was started at 55° C., and after about 5 hours, the pillow was removed, and a pillow with good elastic ridges, high restoring force, and high heat capacity could be obtained.

Example 4 Ammonium acrylate 15.0 Calcium acrylate 1.5 Ethylene glycol 1 α0 Polyethylene glycol diacrylate 0.3 Water
752KPS
α04 Sodium sulfite
When 20 kg of the mixture according to the formulation α02 was placed in a 100 x 200 x 1 (filtered) nylon-polypropylene laminate bag and replaced with N, polymerization was carried out at 20°C for 14 hours, and a cooling sheet with high elasticity and resilience was obtained. .

Example 5 Potassium acrylate 20.0 Potassium acrylate 2.0 Ethylene glycol
10.0 Polyethylene glycol diacrylate 0.2 Water
6 7.8 APS
Q. 03 Sodium sulfite
Example 3 using a mixture according to the formulation of α015
The procedure was repeated.

The physical properties of the obtained pillow-like material were almost the same as in Example 3.

〔Effect of the invention〕

When a gel body is manufactured according to the present invention, even if it is deformed by applying a somewhat strong external pressure because its exterior is restricted by a container, it has the ability to restore its original shape when the stress is removed. Therefore, it exhibits very good properties as a substrate for cooling mufflers, water beds, cushioning materials, aromatic materials, poultice materials, and the like.

Claims (5)

[Claims] (1) Contain a polymerizable monomer aqueous solution containing one or more water-soluble vinyl compounds and a hydrophilic medium as essential components and approximately 20% by weight or less of other copolymerizable vinyl compounds in a synthetic resin container. A method for producing a gel body of a water-containing polymer that exhibits elasticity and is resistant to deformation by being polymerized inside. (2) One type selected from the group of acrylic acid, methacrylic acid, alkali metal salts of acrylic acid, alkali metal salts of methacrylic acid, acrylamide, N-substituted acrylamide, alkoxyalkyl-substituted esters of (meth)acrylic acid, etc. Alternatively, the method for producing a gel body according to claim 1, wherein two or more kinds of compounds are used as the water-soluble vinyl compound. (3) The method for producing a gel body according to claim 1, wherein the monomer concentration of the water-soluble vinyl compound is about 3 to 30% by weight. (4) The method for producing a gel body according to claim 1, which uses a hydrophilic medium consisting of water or water containing ethylene glycol, propylene glycol, glycerin, etc. (5) The method for producing a gel body according to claim 1, wherein a monomer that is water-soluble and capable of performing a crosslinking reaction is used as the water-soluble vinyl compound.