JPS6210164A - Production of aqueous dispersion - Google Patents

Abstract

PURPOSE:To obtain an aq. dispersion which can be easily dispersed in water and gives a coating film having excellent adhesion and resistance to water, oils and chemicals, by continuing melt-kneading by adding small quantities of a basic material and water to a melt-kneaded material. CONSTITUTION:100pts.wt. thermoplastic resin (A) (e.g. PE or PP) which has an MFR of 1g/10min or above and is water-insoluble and water-non-swellable, 1-60pts.wt. thermoplastic polymer (B) whose solubility parameter differs from that of component A by 2 (cal/cm<3>)<0.5> or below and which can be neutralized and/or saponified and contains carboxyl, its anhydride or ester groups attached to the polymer chain at a concn. of at least one mmol equivalent (in terms of the group of the formula) per g of the polymer, and 1-40pts.wt. anionic surfactant (C) are melt-kneaded. A predetermined quantity of a basic material such as an alkali metal or alkaline earth metal oxide or hydroxide and 3-25wt% (based on the total quantity) water are added thereto, and melt- kneading is continued to form 0.1-5mmol equivalent (in terms of the group of the formula) of a carboxylate salt group per g of the polymer in component A, thus causing the phase inversion of a resin solid into aq. dispersion.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for producing an aqueous dispersion capable of forming a film having excellent water resistance, oil resistance, chemical resistance, and adhesion to hydrophobic materials.

Prior Art and Technical Problems of the Invention Aqueous dispersions of various polymers have been known. For example, a fluid aqueous dispersion with a water content of about 30% by weight or more (hereinafter referred to as an aqueous dispersion) is applied to the surface of paper, fibers, plastic molded products, wood, metal, etc. It is dried to form a resin film, which imparts water resistance, oil resistance, and chemical resistance to the base material, and is used as a heat sealing agent.Such aqueous dispersions use water as a dispersion medium. Therefore, they are very advantageous compared to solvent-based ones in terms of flammability, work environment problems, and ease of handling, and are used in a wide range of fields.

In addition to the above-mentioned aqueous dispersions, aqueous dispersions (hereinafter referred to as aqueous dispersions) that have no fluidity and appear to be solids are also known.

In other words, it is a powder-like product known as a powder emulsion, which is redispersed by adding water to form an aqueous dispersion, and its composition contains no water at all, or even if it does, it contains at most 2 to 30% of water. 3% by weight, so there is no need to worry about freezing even at low temperatures, and the advantage is that it is easy to package and transport, and requires less space for storage.

Furthermore, it is possible to directly mix powders and granules that do not want to come into contact with water, such as cement, mortar, and plaster, which is difficult to do with aqueous dispersions, making it possible to manufacture highly processed formulations. are doing.

By the way, in the conventionally known method for producing an aqueous dispersion,
The production of the aqueous dispersions and aqueous dispersions described above could not be carried out in the same manner. That is, in order to produce an aqueous dispersion, an aqueous dispersion with a high water content is first produced by various known methods, and then this aqueous dispersion is sprayed into hot air in a furnace using a sprayer (2. However, if this method uses an aqueous dispersion of a low softening temperature polymer as a raw material, the polymer particles may agglomerate during spraying, or the resulting powder emulsion may be exposed to heat or pressure. Such powder emulsions tend to agglomerate into lumps under the influence of water.When redispersed by adding water, some powder emulsions may not be dispersed, or even if they can be dispersed, the viscosity may become high or the physical properties of the coating may deteriorate. For this reason, various additives such as anti-caking agents and protective colloids are usually added to the aqueous dispersion before spraying or the powder before drying (-
However, if the amount added is not large, there is a problem that there is no texture, resulting in deterioration of the physical properties of the coating film.Furthermore, since a large amount of water is evaporated, energy loss is large and it is not economical. Therefore, it is desired to develop a technique for producing an aqueous dispersion such as a powder emulsion using a method that does not add additives as much as possible and has little energy loss.

Improvements are also desired in the method for producing aqueous dispersions.

That is, conventionally known manufacturing methods can be broadly divided into two methods: a method in which emulsion polymerization is carried out in an aqueous medium in the presence of an emulsifier, and a method in which a molten resin and an aqueous medium are stirred and mixed in the presence of shear force.The former is The latter method is limited in the types of resins that can be polymerized, and has problems such as the complexity of controlling the polymerization reaction and the complexity of the equipment.On the other hand, the latter method has problems such as the complexity of the polymerization reaction control and the complexity of the equipment.On the other hand, the latter method does not know which resins can be applied to this method, and also requires equipment and operating technology. It has the advantage of being relatively simple.

Many proposals have been made regarding the latter method; for example, Japanese Patent Application Laid-open No. 12835/1983 discloses a method in which a kneaded material consisting of a thermoplastic resin and a water-soluble polymer is dispersed in water. However, the film obtained using the aqueous dispersion produced by this method has problems such as low mechanical strength and poor water resistance because it contains a water-soluble polymer. Japanese Patent Publication No. 57-23703 discloses a method of dispersing in water a mixture consisting of polypropylene and a dispersant selected from surfactants and water-soluble or water-swellable polymers. However, this method has the problem that the diameter of the dispersed particles is relatively large and that petroleum resin must be used in combination to reduce the particle diameter, resulting in a sticky film. Also, JP-A-56-21
No. 49 discloses a method for obtaining an aqueous dispersion by kneading an olefin resin and an aqueous solution of partially saponified polyvinyl alcohol, but this method deteriorates the physical properties of the film because it contains a water-soluble resin. Furthermore, the aqueous dispersion obtained by this method has a water content of 30% by weight or more. Yet another method is the technique disclosed in Japanese Patent Publication No. 58-42207, in which a polyolefin and a carboxyl group-containing polyolefin are melt-kneaded, then fed into hot water containing a basic substance, and a shearing force is applied to form a dispersion. Although this method is suitable because it does not contain water-soluble or water-swellable polymers and does not use petroleum resins, on the other hand, the type of raw resin is limited in order to produce particles with small dispersed particle sizes. There is a problem that Furthermore, since the dispersion process is carried out at high temperature and high pressure, there is a problem in that the container used during dispersion must have pressure resistance.

Therefore, in the production of aqueous dispersions, for which various methods have been proposed, water-soluble or water-swellable polymers,
It is desired to develop a method for obtaining an aqueous dispersion of fine particles that can be applied to any resin without using petroleum resin or the like.

Furthermore, there is also a desire for the development of a method for freely and extremely easily producing aqueous dispersions and aqueous dispersions without involving any special steps.

The present inventors previously proposed ([) in an unpublished patent application.
thermoplastic resin, and (ii) neutralizable and/or saponifiable carboxylic acid, anhydride or ester groups attached to the polymer chain, expressed as -C-O- groups per gram of polymer. 0.1 S! A step of melt-kneading a thermoplastic polymer contained at a concentration of 0 or more per mole and (ii1) an organic compound that reacts with a basic substance to become an anionic surfactant;
A basic substance and 6 to 25% by weight of water based on the total amount of water are added to this melt-kneaded product and melt-kneaded, and the organic compound (
ii1) into an anionic surfactant 1-1 and in the thermoplastic polymer (1), 0.1 to 5 mIJ mol per gram of polymer, calculated as 10-0-group, 0 carboxylic acid. It has been proposed that an excellent aqueous dispersion can be obtained by forming salt groups and inverting the phase of the resin solids into an aqueous dispersion.

Outline and Purpose of the Invention The present inventors have developed an anionic surface active composition x+i together with the thermoplastic resin (1) and the functional thermoplastic resin (ii).
When D is melt-kneaded in advance, by simply adding a basic substance and a limited amount of water to this kneaded composition and melt-kneading, phase inversion occurs, that is, water becomes the dispersion medium phase and the solid content becomes extremely fine. Conversion to a dispersed particle phase results in an apparently solid aqueous dispersion, and once such phase inversion occurs, it can be supplemented with additional amounts of water, either in-system or externally. It has been found that fine particle size aqueous dispersions with a wide range of water contents can be obtained.

That is, the object of the present invention is to have a resin solid that has an ultrafine particle size and is an oil-in-water dispersion, even though the water content is extremely low. It is an object of the present invention to provide a method for producing an aqueous dispersion having the property of uniformly dispersing ultrafine particles in an aqueous dispersion.

Another object of the present invention is to provide a method for producing an aqueous dispersion in which the dispersed particle size is controlled within an extremely fine range despite not containing any water-soluble or water-swellable components.

Still another object of the present invention is to provide a method for producing an aqueous dispersion of a thermoplastic resin in which phase inversion occurs with a small amount of water.

Still another object of the present invention is to provide a method for producing an aqueous dispersion of a thermoplastic resin without requiring large-scale equipment and with low thermal energy costs.

Structure of the Invention According to the present invention, (1) a thermoplastic resin, (ii) a neutralizable and/or saponifiable carboxylic acid group, an anhydride thereof, or an ester thereof bonded to a polymer chain is A step of melt-kneading a thermoplastic polymer containing a concentration of 0.1 mmol equivalent or more in terms of 10-0- groups per 1 gram and an (i++) anionic surfactant, and adding a basicity to the molten mixture. By adding 3 to 25% by weight of water based on the substance and the total amount and performing melt mixing, 0.1 to 5 mmol in terms of -C-O- group per gram of the polymer is added to the thermoplastic polymer (1). An aqueous dispersion comprising the steps of generating the carboxylate groups and inverting the phase of the resin solids into an aqueous dispersion, and optionally adding an additional amount of water to the aqueous dispersion. A method of manufacturing a product is provided.

Preferred embodiments of the invention The present invention will be explained in detail below.

Contained and Compounded Components The thermoplastic resin (1), which is one of the components constituting the aqueous dispersion of the present invention, is not only water-insoluble and water-swellable, but also has excellent dispersibility in water. It is a thermoplastic resin that lacks, such as low-density polyethylene, high-density polyethylene, polypropylene, poly-1-butene, poly-4-methyl-1-pentene or ethylene, propylene,
':' Polyolefins such as random block copolymers of α-olefins such as tene and 4-methyl-1-pentene, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol T14 combination, ethylene-vinyl chloride Ethylene/vinyl compound copolymers such as copolymers, polystyrene, acrylonitrile/styrene copolymers, AB
S, styrenic resins such as α-methylstyrene/styrene copolymer, polyvinyl chloride, polyvinylidene chloride, vinyl chloride/vinylidene chloride copolymer, polyvinyl compounds such as polymethyl acrylate, polymethyl methacrylate, nylon 6 , polyamides such as nylon 6-6, nylon 6-10, nylon 11, and nylon 12, thermoplastic polyesters such as polyethylene terephthalate and polybutylene terephthalate, polycarbonate, polyphenylene oxide, etc., or mixtures thereof.

Among these thermoplastic resins, olefin resins are particularly preferred, such as polyethylene, polypropylene,
Poly-1-butene, poly-3-methyl-1-butene, poly-4-methyl-1-pentene, poly-6-methyl-1
- Ethylene, propylene, 1-butene, 6, represented by pentene, ethylene/propylene copolymer, ethylene/1-butene copolymer, propylene/1-butene copolymer
-Methyl-1-butene, 4-methyl-1-pentene, 3
- Homo or copolymers of α-olefins such as methyl-1-pentene, 1-heptene, 1-hexene, 1-decene, 1-dodecene, ethylene-butadiene copolymers, ethylene-ethyritenenorbornene copolymers copolymers of α-olefins and conjugated dienes or non-conjugated dienes, ethylene-propylene-butadiene ternary copolymers, ethylene-propylene-dicyclopentadiene hexa-copolymers, ethylene-propylene-ethylidene α represented by norbornene terpolymer, ethylene-propylene-1,5-hexadiene terpolymer, etc.
- Copolymers of two or more olefins and a conjugated diene and a non-conjugated diene can be mentioned. Among these, α-olefin homopolymers or copolymers are preferable for several seconds.

Melt flow rate of thermoplastic resin (+) (ASTMD
1268, MFR) is 1? /10M or more, preferably 5
It is better to have f/10m or more. If the MFR is less than 15'/10, the melt viscosity becomes too high and it becomes difficult to melt and knead, making it difficult to obtain a suitable aqueous dispersion.

The functional thermoplastic polymer (ii), which is another component constituting the aqueous dispersion of the present invention, is neutralized by the above-mentioned thermoplastic resin or the monomer constituting it, or is not neutralized. A monomer having a carboxylic acid group or a monomer having a saponified or non-saponified carboxylic acid ester group is introduced by graft copolymerization, block copolymerization, random copolymerization, etc. The total amount of carboxylic acid salts produced in the polymer by neutralization or saponification with a basic substance is 0.1''-5 in terms of 010-0-group per gram of the polymer. It is adjusted to contain a millimolar amount, particularly 0.2 to 4 millimolar equivalents.At this time, the polymer contains carboxylic acid groups or carboxylic acid ester groups that have not been neutralized or saponified. It may be a partially neutralized product or a partially saponified product.

The thermoplastic polymer (ii) must also not be water-soluble or water-swellable.

If the total amount of neutralized carboxylic acid groups and/or saponified carboxylic ester groups is outside the above range,
It does not work to assist in the dispersion of the thermoplastic resin (1) and cannot form a good dispersion.

Moreover, if it is water-soluble or water-swellable, the physical properties of the coating film will deteriorate.

A thermoplastic polymer containing the above carboxylate group (ii
) is obtained by post-neutralization or post-saponification, the raw material polymer is, for example, a monomer common to the monomers constituting the above-mentioned thermoplastic resin (1), especially α-olefin and ethylenic non-monomer. Copolymerized with saturated carboxylic acid or its ester, unsaturated carboxylic acids such as (meth)acrylic acid, maleic acid, fumaric acid, tetrahydrophthalic acid, itaconic acid, citraconic acid, crotonic acid, incrotonic acid, nadic acid o (endocys-bicyclo[2.2
．． 1] Hept-5-ene-2,6-dicarboxylic acid), maleic anhydride, citraconic anhydride, etc., monoesters, diesters, etc. of methyl, ethyl, propyl, etc. of the above unsaturated carboxylic acids as unsaturated carboxylic acid esters can be exemplified. Of course, instead of copolymerizing a plurality of monomer components, a monomer such as an ethylenically unsaturated carboxylic acid, its anhydride, or its ester may be graft-polymerized to the thermoplastic resin (1), for example, an olefinic resin. It will be obvious to those skilled in the art that this provides thermoplastic polymers for post-neutralization or post-saponification.

Of course, the amount of monomers of these ethylenically unsaturated carboxylic acids, their anhydrides, or their esters introduced must be sufficient to provide the concentration of the carboxylic acid salt specified in the claim. -0-0- group, and the concentration of the polymer must be at least 0.1 mmol/t/1, preferably 0.1 to 5 mmol/t/12 polymer. is within the range of

Basic substances used for neutralization and saponification include substances that act as bases in water such as alkali metals, alkaline earth metals, ammonia and amines, oxides, hydroxides, weak acid salts, and hydrides of alkali metals. , substances that act as bases in water such as oxides, hydroxides, weak acid salts, and hydrides of alkaline earth metals, and alkoxides of these metals. Examples of such substances are shown below.

(1) As alkali metals, for example, sodium, potassium, alkaline earth metals and j-, for example,
Calcium, strontium, barium, (2) Amines include inorganic amines such as hydroxylamine and hydrazine, methylamine, ethylamine, ethanolamine, cyclohexylamine, (3) oxides of alkali metals and alkaline earth metals,
Examples of hydroxides and hydrides include sodium oxide, sodium peroxide, potassium oxide, potassium peroxide,
Calcium oxide, strontium oxide, barium oxide,
Sodium hydroxide, potassium hydroxide, hydroxide, calcium chloride, strontium hydroxide, barium hydroxide, sodium hydride, potassium hydride, calcium hydride, (4)
Weak acid salts of alkali metals and alkaline earth metals include sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, calcium bicarbonate, sodium acetate, potassium acetate, calcium acetate, (5) Compounds of ammonia and amines. Examples include ammonium hydroxide, quaternary ammonium compounds such as tetramethylammonium hydroxide, hydrazine hydrate, and the like.

As the carboxylic acid group or carboxylic acid ester group neutralized or saponified with a basic substance, alkali metal carboxylates such as sodium carboxylate and potassium carboxylate, ammonium carboxylate are suitable, and potassium carboxylate is especially preferred. Preferably 1-.

The functional thermoplastic polymer (ii) is preferably selected to have good compatibility with the target thermoplastic resin (1).

That is, when the purpose is an aqueous dispersion of an olefin resin, a polymer containing an olefin monomer in the polymer chain should be selected. For example, when using polyethylene, polyolefin, ethylene/vinyl acetate copolymer, etc., these maleic acid grafted products, ethylene/(meth)acrylic acid copolymer, ethylene/(meth)acrylic acid copolymer, etc.
It is preferable to use a neutralized or saponified product such as a methyl acrylate copolymer. One guideline for selecting a suitable thermoplastic polymer is the solubility parameter (Sp
value). That is, the difference in solubility parameters between the raw material polymer (II) and the thermoplastic resin (1) before being neutralized or saponified is within 2 (ml/ctd) 2, particularly within 1 (ai/i)T. It is preferable.

As used herein, the solubility parameter (Sp value) has the usual meaning, that is, a value defined as the cube of the cohesive energy density. This solubility parameter defines the contribution Vi of the group to the molar volume and the cohesive energy En of the group as D, F, Va nKltutltn"pr
polymers” (Elte
Vitr, 1972) can be calculated from the formula.

Examples of anionic surfactants (to) include first-class higher fatty acid salts, second-class higher fatty acid salts, first-class high flucol sulfate salts, second-class higher alcohol sulfate salts, and first-class higher alkyl sulfonates. , second category higher alkyl sulfonates, higher alkyl disulfonates, sulfonated higher fatty acid salts, higher fatty acid sulfate ester salts, higher fatty acid ester sulfonates, higher alcohol ether sulfate ester salts, higher alcohol ether sulfonates Any anionic surfactant may be used, such as alkylolated sulfate ester salts of higher fatty acid amides, alkylbenzenesulfone R salts, furkylphenol sulfonates, alkylnaphthalene sulfonates, and alkylbenzimidazole sulfonates. More specific compound names of these surfactants can be found, for example, in Hiroshi Horiguchi's "
Synthetic Surfactants” (1968 Sankyo Publishing) [7].

In the aqueous dispersion according to the present invention, each of the above-mentioned components is present in a certain range of quantitative ratios. That is, thermoplastic resin (1
) 1 to 60 parts by weight of thermoplastic polymer (ii) per 100 parts, in particular 2 to 50 parts by weight, and 1 to 40 parts by weight of anionic surfactant < m ), in particular 2 to 30 parts by weight.
It is preferable that each component (ii) be present in the proportion of parts by weight.When component (ii) is below the proportion of keratin, the dispersion of the thermoplastic resin is insufficient, and when it exceeds this proportion, the desired heat The resulting dispersion has different properties from the original plastic resin. When component (ii+) is below this ratio, it becomes difficult to make the dispersed particles ultra-fine as intended in the present invention, and when it exceeds this ratio, the physical properties of the coating film etc. tend to deteriorate.

The aqueous dispersion according to the present invention further contains water in addition to the above structure, and in a dispersion that can be handled as a solid, the water content is 3 to 25% by weight in the aqueous dispersion. If the water content is less than 3% by weight, an aqueous dispersion cannot be obtained, and if it exceeds 25% by weight, a fluid aqueous dispersion will be obtained. In other words, by having a weight tS in the range of 6 to 25 times, it appears solid and also exhibits the properties described below.

Of course, according to the present invention, a dispersion in the form of a fluid aqueous dispersion can also be prepared, in which case the water content may be 65% by weight or more.

Manufacturing method of aqueous dispersion The first step of the manufacturing method of the present invention is to prepare a thermoplastic resin (i), a thermoplastic polymer (ii), and an anionic surfactant < *i
i) is melt-kneaded. At this time, it should be noted that it is important to simultaneously melt and knead the three components (i), (ii), and (tii) above in order to perform phase inversion; The method of sequentially adding an aqueous solution of an anionic surfactant to a mixed wire resin does not cause phase inversion, and an aqueous dispersion cannot be obtained.

The blending ratios of the thermoplastic resin (1), thermoplastic polymer (ii), and anionic surfactant (tii) are as described above.

The temperature for melt-kneading is at least higher than the higher melting point of the thermoplastic resin or the thermoplastic polymer.

In addition, if the melting point is not clear, the melt viscosity is at least i
The temperature is set at 0"poize or below.

The second step of the production method of the present invention is a step of neutralizing or saponifying a predetermined amount of thermoplastic polymer (ii) by adding a basic substance and water, and at the same time inverting the phase of the resin solid content into an aqueous dispersion. . As for the basic substance, those mentioned above are used, but two or more of these may be used. The basic substance is usually added in the form of an aqueous solution.

In this process, a basic substance reacts with the thermoplastic polymer that was evenly mixed in the first step, causing a neutralization or saponification reaction, which causes phase inversion even in the presence of a small amount of water that is added at the same time. A dispersion with ultrafine particle size is obtained.

Due to the basic substance added in this step, the carboxylic acid salt produced by neutralization and/or saponification in the thermoplastic polymer (ii) is present in 1 gram of the polymer. An amount necessary for neutralization or saponification is added so that the amount becomes 0.1 to 5 mmol equivalent in terms of base. Depending on the amount of water added, at least 5% of the total amount of aqueous dispersion obtained
It should be at least % by weight. If it is less than 6% by weight, no phase inversion will occur and therefore no aqueous dispersion will be obtained. The upper limit of the amount of water added is not particularly limited, but it is preferably at most 90 fk for the purpose of the aqueous dispersion.

In this melt-kneading step of the present invention, 3 to 25% by weight
In the presence of limited moisture, the thermoplastic resin (+) and the thermoplastic polymer (ii) are melt-kneaded, and phase inversion of the resin solid content into an O/IF' type dispersion is performed. It is characterized by being exposed to Water may be added to the melt-kneading system in an amount of more than 25% by weight up to 90% by weight, but even in this case, the phase inversion itself is performed by adding 3 to 25% by weight of water.
This is done in the following stages.

Of course, if the final amount of water added is in the range from 6 to 25% by weight, a solid aqueous dispersion will be obtained; if it exceeds 25% by weight, especially if it is 35% or more, a fluid liquid aqueous dispersion will be obtained. A dispersion is obtained.

The aqueous dispersion produced by melt-kneading by sequential addition of water 1- is then cooled naturally or artificially to room temperature.

At this time, the dispersed particles solidify and become a stable dispersion.

The melt mixing means that can be used in the production method of the present invention may be any known method, but suitable examples include a kneader, a Banbury mixer, a multi-screw extruder, and a Banbury mixer.

In this way, the production method of the present invention allows liquid and solid aqueous dispersions to be obtained extremely easily by simply changing the amount of water added, and the average dispersed particle size of the resulting dispersion is also 5.
In most cases, the Fi is in the range of less than 2μ, and in the case of a solid aqueous dispersion, it has the characteristic that by adding water, it becomes a dispersion in which the solid content is dispersed in the aqueous phase very easily.

In addition, in the preparation of the aqueous dispersion and aqueous dispersion of the present invention, various auxiliary materials that can be normally used in the aqueous dispersion, such as dispersants, emulsifiers, stabilizers, wetting agents, thickeners, foaming agents, Defoamers, coagulants, gelling agents, anti-aging agents,
It goes without saying that softeners, plasticizers, fillers, colorants, numbering agents, anti-blocking agents, mold release agents, and the like may be used in combination.

Structure and properties of aqueous dispersion Important features of the present invention are that the above-mentioned thermoplastic resin (1) and carboxylate type thermoplastic polymer (ii)
) The molten mixture with anionic surfactant is 6 to 2
Based on the discovery that a phase inversion phenomenon occurs in the presence of an extremely small amount of water of 5% by weight, stably fixing the dispersion form of type 07IV, where water becomes a dispersed state and resin solids become a finely dispersed particle phase. It is something. Of course, an additional amount of water can be added to the aqueous dispersion of the present invention, either directly during the manufacturing process or at the aqueous site of the manufacturing process, to obtain a liquid dispersion. However, even in these cases, it is necessary to pay attention to the fact that the phase inversion phenomenon itself takes place in the presence of a small amount of water ranging from 3 to 25%.

The results of observing the particle structure using an electron microscope revealed that the secondary particles of the solid aqueous dispersion of the present invention had a structure in which slightly deformed fine primary particles aggregated quite densely. However, the fact that these missing particles are in the form of oil-in-water (0/F)W dispersion is proven from the following various facts.

Another property of the aqueous dispersion is that its electrical resistance value is 1060.
Most of them are 10'Ω·m or less.

The reason for such a low electrical resistance value is presumed to be that the continuous phase of the dispersion is water and the discontinuous phase is resin. In other words, if the continuous phase is a resin or if the resin powder simply contains less than 25% water by weight, the electrical resistance value will be the value that the resin originally has (generally 107% by weight or less).
~10'80·m, often 1010Ω·m or more).

Another characteristic is that when water is added to an aqueous dispersion, solid components are uniformly dispersed in the aqueous phase. This also suggests that it is a dispersion in which the continuous phase is water.

To measure the electrical resistance value, 1 ctrl electrodes were pasted on the inside of the opposite sides of a 1 crn cubic insulator container, and after the dispersion was press-fitted, the resistance value between the electrodes was measured using an AC resistance measuring device at 60 Hz. Depends on the method used and measured.

To measure the state of dispersion by adding water, the dispersion is poured into cold water, stirred with a regular stirrer equipped with a turbine blade, and then passed through a wire mesh at approximately 1001 NFF and RH, and the particles in the dispersion are observed using a microscope, etc. This can be confirmed by observing.

The dispersed particles of the dispersion of the present invention are substantially spherical particles,
The average particle diameter is in the range of 5μ or less, and in most cases d2μ or less. This particle size can be measured using a Coulter counter.

When the solid aqueous dispersion was redispersed in water and then the water was dried to reduce the solid content only, an electron micrograph was observed, and it was found that the solid particles were substantially spherical fine particles.

The aqueous dispersion according to the present invention has a low water content and is apparently solid, and can be easily turned into an aqueous dispersion by adding water, so there is no risk of freezing, saving space in storage areas, and facilitating transportation. It has characteristics such as ease of packaging. Furthermore, the diameter can be mixed into powders and granules that do not want to come into contact with water, such as cement, mortar, and plaster, and can be used to form water-resistant, oil-resistant, and chemical-resistant films on various materials by re-water dispersion. It can also be used as a heat sealing material. Further, as another mode of utilization of the aqueous dispersion of the present invention, it is also possible to apply an extremely small shearing force or dry it under extremely mild temperature conditions to make it a fine powder and reduce its water content. It can also be used as a binder for new ceramics and as a polymer modifier.

Effects of the Invention According to the present invention, as detailed above, thermoplastic resin (1
), neutralizable and/or saponifiable thermoplastic polymers (ii
) and anionic surfactant, then add a basic substance and a small amount of water, and continue melt-kneading. Phase inversion, in which the resin solid content becomes a fine dispersed particle phase, is easily achieved. Moreover, the aqueous dispersions formed can be handled as solids with low water content, are easily dispersed in water, and have excellent water, oil, and chemical resistance and adhesion to hydrophobic materials. It has the advantage of being able to form a film with excellent properties.

EXAMPLES Preferred examples of the present invention are shown below, but the present invention is not limited to these examples unless otherwise specified.

Example 1 Ethylene-vinyl acetate copolymer resin (
Vinyl acetate content = 19wt, MFR = 15C1/10
min, density = 0.97? /csf, sp value=8.06 (
ad! /ci)') 100 parts by weight, maleic anhydride-grafted polyethylene as a thermoplastic polymer (containing maleic anhydride 11 = 3.3 wt%, 0.67 mmol of OC-0- groups &/1, Mw=270
0, density = 0.94 f /cril, Sp value =
8.06 (cavcr/l) 2) 10 parts by weight and 5 parts by weight of potassium oleate as an anionic surfactant are placed in a pressure kneader and melt-kneaded at 140C for 60 minutes.

Next, 20 parts by weight of alkaline water in which 0.38 parts by weight (1.0 chemical equivalents) of potassium hydroxide, which is necessary to neutralize all the carboxylic acids in the thermoplastic polymer, was dissolved was added to a pump connected to the kneader. Press it in for 5 minutes. The pressure inside the kneader became 3 Kg/(yjG).After that, kneading was continued for 0 minutes, the kneader was cooled to 60C, and the contents were taken out.The contents were a white solid.

This white solid was filled into a 1 crn cubic container, and its electrical resistance was measured to be 2 x 103 Ω・m.In addition, 8 parts by weight of the white solid was poured into 10 parts by weight of water and stirred with a turbine blade stirrer. After that, the dispersion was heated to 100 mes
No residue was observed even though it was passed through a wire mesh.

The dispersion has a solid content concentration of 6 wt% and a viscosity of 110 Cpjp.
H9.9, and the size of the dispersed particles was measured with a Coulter counter, and the average particle size was 0.6 μm. or,
When the carboxylic acid salt produced in the thermoplastic polymer was quantified using an infrared spectrophotometer, it was 0.5Q in terms of 10-0-group.
It was mmol equivalent/2.

Examples 2 to 12° The composition ratios shown in Table 1 were the same as in Example 1.

The results are shown in Table 1.

Example 13゜Co-rotating intermeshing type twin screw extruder (manufactured by Ikegai Iron Works,
100% of the ethylene-vinyl acetate copolymer resin, maleic anhydride grafted polyethylene, and potassium oleate used in Example 1 from the hopper of PCM-30L/D=20).
/1015 at a rate of 115 parts by weight/hour]-1 A 6.6% aqueous solution of potassium hydroxide was continuously fed at a rate of 6 parts by weight/hour from the feed port provided in the pent part of the same extruder. It was continuously extruded at a heating temperature of 90C.

The product was a white solid whose properties are shown in Table 1.

Example 14゜In Example 1, after 20 parts by weight of alkaline water in which 0.38 parts by weight of potassium hydroxide was dissolved was pumped in, an additional 9 parts by weight of alkaline water was added.
0 parts by weight of water was continuously injected and melt-kneaded. Thereafter, the kneader was cooled and the contents were taken out. The contents are a white liquid with resin evenly dispersed, and the solid content is 49 w.
t%, viscosity 1250Cpr, pH 10.0, and average size of dispersed particles was 0.6μ.

Further, when the produced carboxylate salt in the thermoplastic polymer was quantified, it was found to be 51 mmoL equivalent/l in terms of O-C-0- group.

Example 15 The maleic anhydride grafted polyethylene used in Example 1 was made into a neutralized product by the method shown in the following reference example.

10 parts by weight of the neutralized product, 100 parts by weight of the ethylene-vinyl acetate copolymer resin shown in Example 1, and 5 parts by weight of potassium oleate were placed in a pressure kneader and melt-kneaded at 140C for 60 minutes. Next, using a pump connected to the kneader,
20 parts by weight of water is forced in for 5 minutes. The pressure inside the kneader became 3K9/-G. After that, mixing was continued for 30 minutes, and then the kneader was cooled and the contents were taken out. The contents were a white solid. When this white solid was evaluated in the same manner as in Example 1, the water content was 14 cm, and the electrical resistance was 6 x 10
'Omega-image, good dispersibility, and average particle size of 0.8μ.

Reference Example 100 parts by weight of maleic anhydride grafted polyethylene was placed in a normal pressure kneader and melt-kneaded at 140C. Next, 19 parts by weight of alkaline water in which 6.8 parts by weight of potassium hydroxide (1.0 chemical equivalent to the -C-O- group) was dissolved was gradually dropped, and after the water had evaporated, the pages were mixed for 60 minutes. and cool it down. When the produced carboxylic acid salt was quantified, it was found to be 0.66 mmol equivalent/2 in terms of O-C-0- group.

-C-O- group = 0.67 mtnol f/f10-
〇-group = 2. l 4 mmtrl equivalent/fsu-C-0- group = 2.65 mmol f/V10-0
- group = 2.8 [1 mmol equivalent / 2 umbrellas 8 Neutralization per gram of thermoplastic polymer is saponified O 10-0- group equivalent value

Claims (1)

[Claims] (1) (i) thermoplastic resin; (ii) neutralizable and/or saponifiable carboxylic acid, anhydride or ester group bonded to the polymer chain per gram of polymer; There are chemical formulas, tables, etc. ▼ A process of melt-kneading a thermoplastic polymer containing a concentration of 0.1 mmol equivalent or more in terms of base, and (iii) an anionic surfactant, and adding a basic substance and the whole to this melt-kneaded product. 3 to 25% by weight of water is added and melt-kneaded, and the thermoplastic polymer (i) contains ▲numerical formula, chemical formula, table, etc. per gram of polymer▼0.1 to 0.1 to 25% by weight per gram of polymer. 5 mmol equivalents of carboxylate groups and phase inversion of the resin solids into an aqueous dispersion, optionally adding an additional amount of water to the aqueous dispersion. Dispersion manufacturing method.