JPS6198737A - Water-soluble composition - Google Patents

Abstract

PURPOSE:To prepare a composition giving an aqueous solution free from undissolved powder lump in an extremely short time when thrown into gently stirred water, by mixing the powder of a water-soluble polymeric compound with a water-soluble compound which cannot dissolve the powder under heating above the melting point, and cooling the mixture. CONSTITUTION:The powder of a water-soluble polymeric compound and a water-soluble compound which does not dissolve the water-soluble polymeric compound are mixed together by heating above the melting point of said water- soluble compound, and the mixture is cooled. The water-soluble compound is preferably solid at normal temperature and has a melting point of <=100 deg.C. The amount of the compound is 10-100 wt%, preferably 20-70 wt% based on the powder.

Description

Detailed Description of the Invention +11 Object of the Invention [Industrial Field of Application] The present invention relates to an aqueous polymer flocculant solution used in wastewater treatment by coagulation-sedimentation method, an aqueous glue solution used in the textile industry, and a polymer aqueous solution used in civil engineering work. This invention relates to water-soluble compositions used in industrial fields with wide pupil circumference, such as molecular drilling stabilizing fluids.

[Conventional technology]

Powder of a water-soluble polymer compound is poured into water.

When dissolving by stirring, dissolution often occurs in a short time due to the formation of dissolvable lumps (mamako).

In order to avoid this phenomenon, several proposals have been made. For example, it is common practice to make the particles larger so that they do not form a lump, but this has the disadvantage that it takes a long time to dissolve. .

There has also been a proposal to mix a water-soluble inorganic salt into the powder of a water-soluble polymer compound, but it is difficult to avoid the "mamako" phenomenon and is not practical.

A proposal was made to wet the powder of a water-soluble polymer compound with alcohol or mix it with oil (for example, Japanese Patent Publication No. 48-35
708) is an effective method, but when moistening with alcohol, the powder of the water-soluble polymer compound becomes paste-like, and alcohol is a flammable liquid, so it is extremely dangerous to handle. There are drawbacks. Contamination with oils occurs because oils are insoluble in water, so oil droplets float in an aqueous solution.
Not the preferred method.

Furthermore, in the past, in order to prepare an aqueous solution of a water-soluble polymer compound, a large dissolution tank was provided and a dissolution time of several hours to one day was required.

As described above, at present, there is no water-soluble composition that dissolves in water in a short time and has sufficient performance and does not produce maternity.

[Problem that the invention seeks to solve]

Powder of a water-soluble polymer compound that has been ground into fine particles is mixed with water.
The aim is to provide a water-bathable composition that dissolves in a short time and does not cause "mamako" in water. The object of the present invention is to provide a water-soluble composition that leaves no residue.

(2) Structure of the invention [Means for solving the problem] When dissolving the powder of a water-bathable polymer compound, the present inventors
A water-soluble polymer compound that is solid at room temperature is used as a processing agent that suppresses the formation of "mako" in the powder and does not cause the powder to change into a wet, caking, or pasty state that is inconvenient to handle. The present invention was completed based on the discovery that a method of heating a water-soluble compound that does not substantially dissolve together with a powder of a water-bathable polymer compound to a temperature above the melting point, thoroughly mixing the compound, and then cooling the compound to a temperature below the melting point is extremely effective. That is, the present invention provides a water-soluble composition obtained by heating and mixing a water-soluble polymer compound powder and a water-soluble compound that does not dissolve the water-soluble polymer compound powder to a temperature above the melting point of the water-based compound, and then cooling the mixture. It is.

[Water-soluble compound]

Although there are many water-soluble compounds that do not dissolve the water-soluble polymer compound powder that can be used in the present invention, it is preferable to use compounds that are relatively inexpensive and not dangerous in handling. When the water-soluble compound dissolves the water-bathable polymer compound powder.

The powder of the water-soluble polymer compound will swell and the whole will become a lump, which will have the opposite effect on dissolving it in water, so the water-soluble compound used will not dissolve the powder of the water-soluble polymer compound. The water-soluble compound used in the present invention is preferably solid at room temperature and has a melting point of 100° C. or lower. If it is not solid at room temperature, the resulting water-soluble composition will become paste-like or wet (especially during summer).

Examples of water-soluble compounds that tend to block powder particles and cause mako formation when dissolved in water, and which tend to make it difficult to prepare a water-soluble composition when the temperature exceeds 100°C, include, for example, ethylene carbonate, ε -Aminocaprolactam, 1.5-hexanediol, sorbitol, acrylamide, glycol, malic acid, maleic anhydride, and tri-megolpropane are preferred, and these water-fR compounds may be used alone or in combination of two or more- (Moyoi-C7kfi'4 polymer compound powder) There are many powders of water-bathable 1 (6-molecular compound) used in the present invention, such as (meth)acrylic acid, alkali (meth)acrylate, acrylamide, ethylene oxide, Examples include homopolymers and copolymers such as vinyl alcohol, carboxymethylcellulose (CMC), methylcellulose, partially saponified polyacrylic esters, and natural polymer compounds such as alginic soda, gum arabic, gum tragacanth, and xantangano.

[Preparation of water-soluble composition]

The amount of the water-soluble compound added to the powder of the water-soluble polymer compound is 10 to 100% by weight, preferably 20 to 70% by weight.

If the amount used is less than 10% by weight, the effect of preventing "mamako" will be insufficient, and if it exceeds 100% by weight, the original function of the water-soluble polymer compound will be impaired or there will be an economic disadvantage, which is not preferable. The temperature at which the water-soluble polymer compound powder and the water-soluble compound are heated and mixed needs to be higher than the melting point of the water-soluble compound, but it is important that the water-soluble polymer compound powder or the water-soluble compound is not altered in quality. You can choose freely within the range.

Any type of mixing device can be used, but a jacketed kneader is preferred, and the mixing time is usually within 50 minutes.

After heating and mixing in this way, a water-soluble composition is obtained by cooling to below the melting point of the water-soluble compound, but if a large amount of the water-soluble compound is used, the powder may aggregate and form large particles. Therefore, adjust the particle size to an appropriate size by crushing or sieving as necessary.

[Effect]

The water-soluble composition of the present invention is composed of a water-soluble polymer compound powder and a specific water-soluble compound, and its form is thought to be that the water-soluble polymer compound powder is coated with a water-soluble compound. Since it is difficult to produce "mamako", it is possible to prepare an aqueous solution of the desired polymer compound in a very short time by adding it to gently stirred water.

[Examples and comparative examples]

The weight average molecular weights of the water bathing polymer compounds in the following six examples were measured by the intrinsic viscosity method.

Example 1 14 of polyacrylamide with a weight average molecular weight of about 9 million
Ethylene carbonate 5 to 100g of powder of 9μm or less
0g was added and heated to 45-50°C to melt ethylene carbonate (melting point 36°C), thoroughly mixed and cooled to room temperature.

Some of the particles are agglomerated, so loosen the coarse particles 42
A water-soluble composition was obtained by passing the entire mixture through a 011m sieve.

When 15 g of the above water-soluble composition was poured into water 102 at 25° C. which was being gently stirred, a uniform aqueous solution was obtained in 5 to 6 minutes.

Comparative Example 1 An attempt was made to dissolve polyacrylamide in water in the same manner as in Example 1 using polyacrylamide that did not use ethylene carbonate. It took.

Examples 2 to 6 and Comparative Examples 2 and 3 Water-soluble compositions were produced according to Example 1, except that the water-soluble polymer compound with a weight average molecular weight of 9 million to 11 million and the type of water-soluble compound were changed, and dissolved. I conducted a test.

The results are shown in Table 1.

Comparative Examples 4 to 6 14 of polyacrylamide with a weight average molecular weight of about 9 million
A water-soluble composition was prepared by adding conventionally used kerosene, ethyl alcohol, or ethylene glycol to a powder of 9 μm or less, and a dissolution test in 1 water was conducted in the same manner as in Example 1. Table 2 (3) Effects of the Invention The water-soluble composition of the present invention itself is a powder with sufficient fluidity at room temperature, and can be dissolved in water in a short time using an extremely small device. It does not form lumps in water, does not produce insoluble matter, and has great economic effects.

Claims (1)

[Claims] 1. A water-soluble composition obtained by heating and mixing a water-soluble polymer compound powder and a water-soluble compound that does not dissolve the water-soluble polymer compound powder to a temperature above the melting point of the water-soluble compound, and then cooling the mixture.