JPH03281602A - Polymer emulsion and polymer - Google Patents

Abstract

PURPOSE:To obtain an easily coagulable polymer emulsion by emulsion- polymerizing a polymerizable monomer in the presence of a specified surfactant which can be easily decomposed under acidic conditions. CONSTITUTION:A polymer emulsion obtained by emulsion-polymerizing a polymerizable monomer in an aqueous medium in the presence of a surfactant having a 1,3-dioxolane ring in the molecule, a polymerization initiator, a mol.wt. modifier, etc. Because the surfactant used is decomposed under acidic conditions, the pH of the polymerization system needs to be maintained at 4 or above. Therefore, when the emulsion polymerization is performed with a persulfate such as ammonium persulfate or potassium persulfate which is a general polymerization initiator for emulsion polymerization, it is necessary that a definite amount of a pH buffer be added. When the emulsion polymerization is performed in the presence of the so-called redox polymerization initiator, the pH does not change and can be easily controlled, so that this initiator is desirable as the initiator used in this polymerization.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a polymer emulsion and a polymer obtained by emulsion polymerization using a surfactant having a specific structure that has the ability to decompose under acidic conditions.

[Conventional technology]

Polymers used in the electronics field are
It is required that the metal content be as low as possible.

On the other hand, the so-called emulsion polymerization method is a polymerization method that is easy to perform polymerization operations and has a wide range of applications, but requires a relatively large amount of surfactant for polymerization.

For this reason, even if the resulting polymer is thoroughly washed with water, it has a high metal content and is often unsuitable for the electronics field.

Conventionally, for this purpose, attempts have been made to polymerize using nonionic surfactants as surfactants that do not contain metal ions, but in many cases there have been problems with polymerization stability.

Further, although improvements have been made to methods for coagulating and washing the resulting polymer, these methods are insufficient for use in the electronics field using emulsion polymerization polymers.

On the other hand, in some fields of application of polymer emulsions, it is desirable to have polymer emulsions that have good dispersion stability up to a certain process step and have the ability to quickly become unstable when certain operations are applied to them. was.

Conventionally, it has been known to add polyvalent metal ion salts such as calcium, magnesium, and aluminum to polymer emulsions for this purpose, but these additives have the problem of reducing the physical properties of the resulting latex product. there were.

[Problem to be solved by the invention]

The present invention was made against the background of the above-mentioned conventional technical problems, and provides a polymer emulsion that can be easily coagulated by emulsion polymerization using a specific surfactant that easily decomposes under acidic conditions, and a polymer emulsion that has a low metal content. The aim is to obtain less polymer.

[Means to solve the problem]

The present invention provides a polymer emulsion produced by emulsion polymerization in the presence of a surfactant having a 1,3-dioxolane ring in its molecule.

The polymer emulsion of the present invention has 1,3
- Obtained by emulsion polymerization of polymerizable monomers using a surfactant having a dioxolane ring in the molecule, a polymerization initiator, a molecule regulating side, etc.

The surfactant used in the present invention has a 1,3-dioxolane ring in its molecule, and its structural formula is represented by the following formula (I).

[In the formula, R1 and R2 are the same or different, and are a hydrogen atom or an alkyl group or alkenyl group having 1 to 20 carbon atoms (however, R' and R2 are not both hydrogen atoms), R3 and R4 are hydrogen atoms, Alternatively, it represents an alkyl group or alkyl ether group having 1 to 10 carbon atoms and having any one of a sulfonate, a sulfate ester salt, a carboxylate, a quaternary ammonium salt, an aminocarboxylate, and an aminosulfonate. ] In the above formula (1), R1 and R2 have 1 to 2 carbon atoms;
Examples of the alkyl group 0 include methyl group, ethyl group, propyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group,
Tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, icosyl group, etc., and alkenyl groups include hexadecenyl group, octadecenyl group, octadecajenyl group, ophtadetrienyl group, etc. Can be mentioned.

R1 and R2 preferably have a hydrogen atom or a carbon number of 1
~18 alkyl or alkenyl groups.

In addition, in formula (I) above, the alkyl group having 1 to 10 carbon atoms in R3-R4 includes a methyl group, an ethyl group, a propyl group, a pentyl group, a hexyl group, a heptyl group,
Examples of the octyl group, nonyl group, and decyl group, and examples of the alkyl ether group include propyloxymethyl group and butyloxymethyl group.

The number of carbon atoms in the alkyl group or alkyl ether group in R3-R4 is preferably 1 to 8, more preferably 1.
~6.

Specific examples of this surfactant include: CH.

/ \ COONa.

\ CH2 C4 8 03 Na.

R3 / \ COONa.

\ CH.

C4 8 So.

Na.

Examples include.

Moreover, the following methods can be mentioned as methods for producing these surfactants.

That is, by reacting aldehydes or ketones with epoxy compounds such as ethyl 2゜3-epoxybutyrate, epichlorohydrin, and ebibromohydrin, or glycerin in the presence of an acid catalyst, long-chain alkyl groups can be formed. 1°3-dioxolane ester having 4
-Chloromethyl 1゜3-dioxolane, 4-bromomethyl-1,3-dioxolane, 4-hydroxymethyl-1
, 3-dioxolane and then saponification, quaternary ammonium formation, or sulfonation to produce the desired surfactant.

The polymer emulsion of the present invention can be obtained by carrying out a conventional emulsion polymerization operation using the above-mentioned surfactant.

However, since the surfactant used in the present invention decomposes in acidic conditions, it is necessary to maintain the pH of the polymerization system at 4 or higher. For this reason, when carrying out emulsion polymerization using persulfates such as ammonium persulfate and potassium persulfate, which are polymerization initiators for emulsion polymerization, it is necessary to add a certain amount of pH buffer.

Here, when emulsion polymerization is carried out using a so-called redox polymerization initiator, it is preferable as the polymerization initiator of the present invention because there is no change in pH and the pH can be easily controlled.

This redox polymerization initiator is a combination of an organic or inorganic oxidizing agent and an organic or inorganic reducing agent.

Specific examples of the oxidizing agent include cumene hydroperoxide, diisopropylbenzene hydroperoxide, paramenthane hydroperoxide, and hydrogen peroxide.

Specific examples of the reducing agent include sugar-containing sodium pyrophosphate, sodium formaldehyde sulfoxide, ferrous sulfate, and sodium ascorbate.

The polymerization monomer used in the present invention is not particularly limited as long as it can be emulsion polymerized, but examples include aromatic vinyl compounds such as styrene, vinyltoluene, and divinylbenzene; vinyl cyanide compounds such as acrylonitrile and methacrylate; methyl Acrylic acid esters such as acrylate, ethyl acrylate, n-butyl acrylate, and 2-ethylhexyl acrylate; Methacrylic acid esters such as methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, ethylene glycol dimethacrylate, and 2-ethylhexyl methacrylate: Vinyl acetate Vinyl organic acids such as; vinyl ethers such as vinyl methyl ether and vinyl phenyl ether; butadiene, isoprene, 1-chloro-1,3-
Aliphatic conjugated diene compounds such as butadiene; halogenated unsaturated compounds such as vinyl chloride, vinylidene chloride, vinylidene bromide, and vinyl bromide; acrylic acid, methacrylic acid,
Examples include mono- or dicarboxylic acids such as maleic acid, fumaric acid, and itaconic acid, and acid anhydrides of dicarboxylic acids.

In addition, epoxy compounds such as glycidyl acrylate and glycidyl methacrylate; amino compounds such as dimethylaminoethyl acrylate; and sulfonic acid compounds such as sodium styrene sulfonic acid can also be used as required.

Examples of molecular weight regulators include halogenated hydrocarbons such as chloroform, bromoform, carbon tetrachloride, and carbon tetrabromide; n-hexyl mercaptan, n-octyl mercaptan, t-octyl mercaptan, n-dodecyl mercaptan, and t-dodecyl. All those usable in ordinary emulsion polymerization can be used, such as mercaptans such as mercaptan and n-stearyl mercaptan; xanthogens such as dimethylxanthogen disulfide and diisobrobyl xanthogen disulfide.

There is no particular restriction on the amount of the surfactant having a 1,3-dioxolane ring in the molecule when producing the polymer emulsion of the present invention by emulsion polymerization, but in order to obtain the substantial effects of the present invention, The amount is about 0.05 to 10 parts by weight, preferably about 0.1 to 7 parts by weight, based on 100 parts by weight of the polymerization monomer.

In addition, in the emulsion polymerization applicable to the present invention, in addition to the above-mentioned specific surfactants, it is also possible to use ordinary anionic surfactants, cationic surfactants, nonionic surfactants, etc. .

Emulsion polymerization is carried out, for example, by charging the polymerization monomers all at once. However, a method may also be used in which a part of the polymerizable monomer is polymerized and then the remaining part is added intermittently or continuously as the polymerization progresses.

Alternatively, a method can be adopted in which all of the polymerization monomers are added continuously from the beginning of the polymerization.

The polymerization temperature is usually 3 to 95°C. The polymerization time is usually
1 to 40 hours.

The polymer emulsion obtained in the present invention is obtained as a sufficiently stable dispersion.

When the pH of this polymer emulsion is lowered using an organic or inorganic acid, the dioxolane compound is cleaved into water-soluble glycol and carbonyl compounds in a short time, and the emulsion is separated into water and polymer.

Thus, the polymer emulsion of the present invention is useful as a polymer emulsion whose colloidal state can be easily broken at a desired point.

In addition, the polymer obtained by destroying the colloidal state can easily remove components derived from the surfactant by washing with water, and is particularly effective in removing metal ion components.

Therefore, although the polymer obtained in the present invention is obtained by emulsion polymerization, the metal content is 200 p.
Since the content is as low as Pm or less, preferably 1100 ppm or less, and more preferably 50 ppm or less, it can be particularly usefully used in the electronics field.

Note that the metal content herein refers to the total metal analysis value obtained by atomic absorption analysis of the ash content obtained by incinerating the sample. For ordinary samples, the analytical values for sodium and potassium can be substituted.

〔Example〕

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

Note that parts and percentages in the examples are based on weight unless otherwise specified.

Examples 1-5, Comparative Examples 1-3 Five dishes hematopoiesis five ■ rise Surfactants A-C were synthesized as follows.

Surfactant A; 2-tridecanone 100.0g, glycerin 56.0g
, 200M benzene in 1.0g paratoluenesulfonic acid
1 was added and a dehydration condensation reaction was carried out under reflux for 24 hours, followed by washing with 50 d of 5% aqueous potassium carbonate solution and 50 d of water.
By distilling under reduced pressure (140°C, 10.3 mmHg), 118.2 g of 2-methyl-2-undecyl-4-hydroxymethyl-1,3 dioxolane was obtained.

To this 4-hydroxymethyl-1,3-dioxolane compound, 18.8 g of sodium hydroxide and 200 d of benzene were added.
was added and heated to 50°C.

There, 64.0 g of 1,4-butanesultone was dropped,
After the dropwise addition was completed, the reaction temperature was maintained at 75°C and the reaction was continued for 6 hours. After the reaction was completed, the temperature was lowered to 50"C, 500 d of ethanol was added, the precipitated salt was removed by filtration, and the temperature was further lowered to crystallize. This was purified by recrystallization in ethanol. 162.0 g of a sodium sulfonic acid salt type 1,3-dioxolane compound was obtained as a product.

The results of 'H-NMR (D, O20) analysis of this compound are 0.88 (t, 3H, CH3, J=6Hz), 1
．． 00-2.00 (m, 27H1 (m, 2H, cHt
soi), 3゜4. 50 (m, 7 H, 0
It was CHCHHzCH,OCH.

Surfactant B; 40- 0+ CH.

/ Dissolve 19.8 g of 2-tridecanone and 1.5 g of boron trifluoride ether complex salt in 30 d of carbon tetrachloride, and add 2-tridecanone to this solution.
, 13.0 g of ethyl 3-epoxy acetate was added dropwise over 30 minutes.

After further stirring at 50°C for 4 hours, 40d of water and 1501d of diethyl ether were added to extract the product into an ether layer, which was distilled under reduced pressure (160°C/4 m
2-methyl-2 purified by
-undecyl-4-ethoxycarbonyl-5-methyl-
8.8 g of 1,3-dioxolane was obtained. Add about an equivalent amount of sodium hydroxide to this, and add 4 equivalents of sodium hydroxide in ethyl alcohol.
The mixture was refluxed for a period of time to saponify it. Although the saponification was carried out in a quantitative manner, diethyl ether was added after the reaction to remove unreacted ester, and the desired carboxylic acid sodium salt type 1,3 was obtained.
- A dioxolane derivative was obtained.

As a result of elemental analysis, carbon atoms = 69.76%, hydrogen atoms =
11.03%, calculated values as C,,H,,O,Na, carbon atoms = 69.47%, hydrogen atoms = 11.
It was almost the same as 0.05%.

In addition, the result of 'H-NMR (D!O1δ) analysis of this derivative is 0.90 (t, 3H, CH,, J=6H
z), 1.10-1.70 (m, 26H1CH, +C
00CCH, +CH, C-Coo), 4.25 ((
i, 2H, C00CH,, J=7Hz), 4.57 (
m, 2H, 0CHCHO).

Surfactant C: Dissolve 19.8 g of 2-tridecanone and 1.5 g of boron trifufluoride ether complex salt in 30 d of carbon tetrachloride, and add 16.4 g of shrimp bromohydrin to this solution until the liquid temperature does not exceed 60°C. The mixture was added dropwise and further stirred at 50°C for 6 hours.

40 d of water and 150 d of diethyl ether to the reaction mixture.
1d to extract the product into an ether layer, which was distilled under reduced pressure (115 °C/3 m Hg).
23.7 g of purified 2-methyl-2-undecyl-4-bromomethyl-1,3-dioxolane (yield = 84%)
) was obtained.

This 2-methyl-2-undecyl-4-bromomethyl-
5.0 g of 1,3-dioxolane and 3.3 g of diethylamine
5.2 g of a 4-diethylaminomethyl derivative was obtained by dissolving the 4-diethylaminomethyl derivative in benzene, reacting in a sealed tube at 140°C for 12 hours, and further distilling under reduced pressure (150°C/4 degrees Hg).

Furthermore, methyl iodide was added and reacted in a sealed tube at 80°C for 12 hours to obtain the desired 1,3
- A dioxolane compound was obtained.

As a result of elemental analysis, carbon atoms = 54.57%, hydrogen atoms =
9.62%, nitrogen atoms = 2.80%, C, 2H
,, carbon atom calculated as NI = 54.65%
, hydrogen atoms = 9.59%, and nitrogen atoms = 2.90%.

Moreover, the result of 'H-NMR (CDCf3, δ) analysis of this derivative is 0.88 (t, 3H, CH.

J=6Hz), 1.10-1.85 (m, 32H1C
H, CN" CHz CN", J=7Hz), 4. 00-4.
80 (m, 3H, 0CHCHzO).

A polymerization recipe having the composition shown in Table 1 was charged into an autoclave equipped with a stirrer and having a volume of 1 ON, and emulsion polymerization was carried out at the temperature shown in Table 1.

Sampling was performed during the polymerization, and when the polymerization conversion rate reached 80%, N,N-diethylhydroxylamine was added as a polymerization inhibitor to stop the polymerization.

The results are also shown in Table 1.

In Examples 1 to 5, the polymerization stability was good, and the colloidal stability of the obtained polymer emulsions was also excellent.

When 1% hydrochloric acid was added to these polymer emulsions to lower the pH of the system to 1.5, the emulsions were immediately destroyed and the polymers precipitated.

Each of these polymers was thoroughly washed with water and heated to 100°C.
Drying was performed for 5 hours to obtain a dry polymer. The ash content (%) when this dry polymer was incinerated in a crucible in an electric furnace at 580°C and the content of sodium and potassium metal components in the polymer sample when this ash content was subjected to atomic projection analysis were determined. It is shown in Table 1. In Table 1, the polymerization rate is expressed as the time until the polymerization conversion rate reaches 80%.

In Examples 1 to 5, the destruction of the polymer emulsion was rapid, and due to the effect of using the specific surfactant, the effect of removing metal components by water washing was high, and the amount of metal in the obtained polymer was small.

On the other hand, in Comparative Examples 1 to 3, emulsion polymerization was carried out using a polymerization recipe using a conventional surfactant as an emulsifier.

The polymer emulsions of Comparative Examples 1-2 were those of Examples 1-5.
Colloids could not be destroyed under the same conditions. For this reason, calcium chloride was added to destroy the colloid. For this reason, only polymers with high metal content could be obtained. In addition, colloid destruction was performed on the polymer emulsion of Comparative Example 3 under the same conditions as Examples 1 to 5, but the speed was slow. Moreover, the efficiency of removing the surfactant from the polymer by washing with water was low, and the metal content in the obtained polymer was high.

〔Effect of the invention〕

The polymer emulzidine of the present invention is characterized by being more acidic and capable of destroying colloids in a shorter time than those produced by conventional emulsion polymerization. For this reason, it is used in systems such as in-line coatings, which dry quickly by separating water by coating with good fluidity and then destroying colloids under low pH conditions. It can be used as a functional polymer emulsion.

In addition, the polymer obtained by the present invention has a low metal content that cannot be obtained by conventional emulsion polymerization because the 1,3-dioxolane ring is cleaved by destroying the colloid with acidity and is easily removed by washing with water. A polymer is obtained. Therefore, the polymer of the present invention can be used in adhesives, fillers, sealants, coating materials, insulation materials, blend modifiers, packaging materials, etc. in the electronics field.

Claims (2)

[Claims] (1) A polymer emulsion produced by emulsion polymerization in the presence of a surfactant having a 1,3-dioxolane ring in its molecule. (2) A polymer having a metal content of 200 ppm or less, produced by emulsion polymerization in the presence of a surfactant having a 1,3-dioxolane ring in the molecule.