JPS5938207A - Surfactant for use in emulsion polymerization - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an unsaturated monomer surfactant for emulsion polymerization. More specifically, the present invention is suitable for use in emulsion polymerization of ethylenically unsaturated - tl salmon suspensions, conjugated diene unsaturated salmon bodies, or mixtures of these monomers [7, with extremely low foaming and surface tension. The present invention relates to a surfactant for emulsion polymerization that can provide an emulsion with high oxidation and good mechanical stability.

Emulsions, which are so-called emulsions of various polymeric substances, use water as a solvent, so they are safer for the environment and the human body than so-called solvent-based products, and are used in paints, textile processing agents, and adhesives. It is now widely used as a paper processing agent.

In the production of emulsions, it is necessary to strengthen the polymerization field,
For the stabilization of emulsions produced, generally chlorgyl benzene sulfonate.

Anionic surfactants such as alkyl-61 acid varnish/allic salts, J-class fatty acid salts, and nonionic surfactants such as polyoxyethylene-17 alkyl phenyl ether, alone or as a mixture, have a concentration of 0.5% based on the raw material monomer. ~5fold In,
However, emulsions produced using these surfactant F1 agents have high foaming properties and low surface tension, making them difficult to manufacture or use.
7, several problems have arisen, including: That is, (1) the foamability is greatly rounded, the amount of time required to prepare the emulsion during emulsion production is large, and the observation of the reaction state is insufficient. ■When painting with emulsion, bubbles may cause pinholes. 0 If the surface tension is low, the adhesive strength tends to be weak when the emulsion is used as an adhesive, and when it is used as a fiber processing agent, the emulsion's permeability to the textile fabric is too high, causing the fibers to absorb the fibers themselves. It becomes difficult to take advantage of sexuality. ■ Furthermore, since the surfactant is nonvolatile,
It remains in the film prepared from the emulsion and provides water resistance and adhesion of the film.

It has also been pointed out that it causes a decrease in tensile strength, heat resistance, weather resistance, etc.

The present inventors are aware of the current situation, and the following:1. Based on the assumption that these problems can theoretically be solved by eliminating the presence of low-molecular-weight surfactants in the emulsion, we have conducted intensive research on emulsions containing carboxyl groups or sulfonic acid groups. 1 or more unsaturated monomers, and an ester monomer of an aliphatic alcohol having 8 to 20 carbon atoms and acrylic acid or/and methacrylic acid as essential copolymerization components, are polymerized in a specific ratio. The salt of the copolymer was mixed with a surfactant for emulsion polymerization.
The present inventors have discovered that when used, an emulsion with extremely low foaming properties, high surface tension, and excellent polymerization stability and mechanical stability can be prepared, and the present invention has been completed.

ff1J 1-4th invention) 2 Component (1) (Jl)
(1) One or more monomers selected from the group consisting of unsaturated monomers containing a carboxyl group or a sulfonic acid group, (11) an aliphatic alcohol having 8 to 20 carbon atoms, and acrylic acid or/and Contains more than 60 methacrylic acid and Nisdel monomer as essential components2,
When the sum of component (1,) and component (u) is 1+10 and [7, component (1) is ff5~99 times, component (H11
~15 M, unfortunately copolymerized 2nd - [Made of the salt of the obtained copolymer, extremely low foaming, high surface tension, and good polymerization stability and mechanical stability. The purpose of the present invention is to provide a surfactant for emulsion polymerization that provides a suitable emulsion.

The emulsified JR combined surfactant of the present invention is a polymer type surfactant that has both a hydrophobic part and a hydrophilic part in its molecule, and these parts are appropriately balanced. Surfactants belonging to this category and 1. Conventionally, copolymers of higher alkyl mercaptans and monomers having a carboxyl group or a sulfonic acid group (Japanese Patent Publication No. 47-54832, Japanese Patent Application Laid-Open No. 54-21
41115) and a combination of an unsaturated carboxylic acid ester of a higher alcohol and a monomer having a carboxyl group or a sulfonic acid group (Japanese Unexamined Patent Publication No. 55-18490).

However, since the former uses a large number of mercaptans with very large chain transfer constants to introduce hydrophobic groups, the polymerization reaction proceeds smoothly when the surfactant is used in emulsion polymerization due to the remaining unreacted mercaptans. There is a tendency that more polymerization initiators are required than those normally used, or that the degree of polymerization of the produced polymer decreases.

The latter has a sufficient balance between hydrophilic groups and hydrophobic groups, and cannot be said to have a sufficiently satisfactory performance as a surfactant for emulsion polymerization.

However, the surfactant for emulsion polymerization of the present invention does not have these drawbacks and has excellent performance.

The carboxyl group-containing unsaturated monomer used in the present invention includes acrylic acid and methacrylic acid.

Itaconic acid, etc. include JL, sulfonic acid group-containing monomers and L-C, 2-acrylamido-2-methylpropanesulfonic acid, and styrenesulfonic acid.

Examples include allyl sulfone ω, methallyl sulfonic acid, vinyl sulfonic acid, and the like.

Ester monomers of aliphatic alcohol having 8 to 20 carbon atoms and acrylic acid, methacrylic acid J: include decyl acrylate-1, decyl methacrylate, lauryl acrylate, lauryl methacrylate, and sudearyl acrylate.

Surfactant for emulsion polymerization of the present invention: the copolymerization ratio of the above-mentioned component (11) and component (■ is very critical, i.e. the sum of component (Tl and component (Ill) is at least 60 tlL in the copolymer.
- it is necessary to contain more than - and component (I)
When the sum of component (II) and component (II) is taken as 100, component (I
It is 85 to 99 weights, ingredients (ITI is 1 to 15 weights)
- must be That is, in the emulsion of the present invention (which does not affect the Pj゛ability of the table surfactant), other nonionic unsaturated monomers may be copolymerized; No system;!
j7HiJ of the Japanese monomer: 40 heavy J+] must be less than or equal to 40.

Such nonionic unsaturated monomers (1) ester monomers of aliphatic alcohols having 1 to 6 carbon atoms and acrylic acid or methacrylic acid, acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, 2
-hydroyacidyl acrylate, 2-hydroxyethyl meccrylate, styrene, etc. can be mentioned.

In the surfactant for emulsion polymerization of the present invention, 1: the molecular group of the agent (number average molecule - 111, hereinafter molecular group +', J, all number average molecules 1
(meaning 11-) 1 is preferably +000 to +50,000, more preferably 3,000 to +5,000. When a copolymer salt having a molecule J4 of less than 1000 is subjected to emulsion polymerization, the foamability of the resulting emulsion increases and its surface tension also decreases. Sweet molecular string is 5ooo
In the case of a copolymer salt exceeding 0, the viscosity of the resulting emulsion is too high to be Oshu-like.

The copolymer used in the present invention can be synthesized by any method such as solution polymerization or bulk polymerization. However, it is preferable to synthesize it by a solution polymerization method in a lower alcohol or a mixed solvent of lower alcohol and water. Regarding the method of adding each monomer to the polymerization reaction system, there are two methods: batch addition, nine-part addition, and continuous addition.

After the copolymerization reaction is completed, add an appropriate amount of water and then add a basic substance to adjust l-1) 1 to 6 to OK. After that, an aqueous solution of the copolymer salt can be obtained by removing the alcohol content from the topping or the like. basic substances and j
, 7 θ5, °r alkali metal hydroxyl or carbonate,
Examples include organic amines such as ammonia and 2-amino-2-methyl-1-propanol. The surfactant of the present invention comprising the copolymer salt is conveniently prepared in an aqueous solution having a concentration of 10 to 50% and subjected to the emulsion polymerization reaction.

The emulsion polymerization reaction using the surfactant for emulsion polymerization of the present invention can be carried out by a known method. for example,
1ooJrr; 80 to 200 parts of water per part of It, 0.5 to 10i of the surfactant for emulsion polymerization of the present invention: A
Add part t, a suitable polymerization initiator, an inorganic salt, a chain regulator, etc. as necessary, and carry out the polymerization reaction by setting an appropriate temperature in a nitrogen atmosphere. Examples of monomers that can be used are aromatic vinyl monomers such as styrene, α-methylstyrene, and methyl acrylate.

Conjugated dienes exclusively for acrylic acid or Nisder methacrylate such as Pudyl acrylate and Medyl methacrylate, Vinyl chloride, Vinyl halides such as vinylidene chloride or Vinylidene fA, Vinyl Nisder such as vinyl acetate, Butadiene, and Isoprene. be able to. These single 11
It may be used alone or in combination with a mixture of two or more of them.

Next, the present invention will be explained in more detail with reference to Examples, but the present invention is limited to these Examples. It's not something you can do.

In addition, all the parts in the example] "are standard.

Synthesis of copolymer salt> Synthesis Examples 1 to 5 and Synthesis Comparison fFIJ1 to 5 Synthesis of copolymers with the monomer composition shown in Table 1 1 to 1 Hydroxylation of them] By neutralizing with lium, An aqueous solution of the copolymer salt was obtained. The molecular weight of the copolymer is also listed in Table 1. Molecule 11:ij: Borisdylene of known molecular weight was used as a standard substance, and flRG-40 manufactured by Shimabara Seisakusho was added to the unneutralized copolymer.
, 15, and 10 were obtained in application 1- of gel permeation chromatography using three wooden columns. In addition, for the copolymerization reaction t, 500 parts of isopropyl alcohol and 0.4 parts of °rzobisisoputyronitrile are mixed and dissolved for 100 parts of the monomer mixture, and the mixture is stirred at 75°C for 8 hours under a nitrogen gas atmosphere. This was done by Regardless of the jt, the polymerization rate was 1%.

After the completion of the copolymerization reaction, 600 parts of ion-exchanged water was added, and then an aqueous solution of sodium hydroxide was added until the pH became 6 to 8. Isopropyl alcohol and water were removed with topping, and the copolymer was - Salt concentration is 20% by weight
It was made to mix with an aqueous solution of.

7, Te 1 T, M A Nilauryl methacrylate MAA Ni methacrylic acid A Niacrylic acid s As Ni r lysilylphonic acid AMI'8: 2-acrylamido'-2-methylpropanesulfonic acid AN: Acrylonitrile 2-MW: 2 -Mercaptoeta Example Synthesis Example 6 Hydroxylation of the copolymer in Synthesis Example 1) VC [- Copolymer dμ
71 (obtain a solution).

81. of emulsion. ]Made Part 1>Synthesis 51! Examples 1 to 61 Synthesis Comparative Examples 1 to 5 and commercially available polymer surfactant po17WetKX-4 (manufactured by Uniroyal Co., Ltd. of Yoneba) and commercially available anionic surfactant dodecylbenzenesulfone, sodium acid, An emulsion was prepared according to the following recipe using sodium lauryl sulfate, sodium polyoxyethylene (4) nonylphenyl ether sulfate, and sodium polyoxyethylene (18) nonylphenyl needle fit acid as surfactants for emulsion polymerization. .

140 parts of distilled water, 1.3 parts of a surfactant for emulsion polymerization, and 1.5 parts of methacrylic acid were placed in a four-way adjustable flask equipped with a reflux condenser, a stirrer, 9 dropping funnels, and an inlet tube, and ammonia was added. After adjusting the TIH to 4 to 4.5 with water,
To raise the temperature to 80℃ under nitrogen atmosphere. A suitable amount of a monomer mixture of 15 parts of styrene, 50 parts of butyl acrylate, and 35 parts of methyl methacrylate was added dropwise from the dropping funnel [2, then stirred and pressed to form an aqueous solution containing 0.5 part of ammonium persulfate.
Add part to start the UN reaction. In the evening, 5 minutes after the start of the reaction, the monomer mixture was added dropwise over a period of 2 hours;
-1 An emulsion was obtained by further aging at 80°C for 1 hour. 1) Ht of emulsion with ammonia water
The surface tension and foaming property of the emulsion were adjusted to e and o.
Polymerization Stability 1 Mechanical stability, M unit ratio, and particle size were measured and the results are shown in Table 2.

Pa 2
(tl main) Commercial product A: p
olyWet, KX-4/IB:)'Decylbenzenesulfone 1t-j-) +) Uno,〃0 Nilauryl sulfate sodium Uno D: Polyoxyethylene (4) Nonylphenyl di-
Sodium sulfate u w: Bo + 4 Oxyburene (18) Nonylphenyl Needle 2 The method for measuring each item is as follows: Measurements were made with a Wilhelmy at 23°C.

500 mg of emulsion 100 diluted to a foaming concentration of 5
into a graduated cylinder i1. , Agitation 11 (Japan S
ervo Co., Ltd. , model IM'r 8
8 15) Stir for 5 minutes at a maximum rotational speed of 1350 rpm for 5 minutes at A seconds, measure the overall appearance of the sample including bubbles, and calculate the magnification to the original sample volume. did.

The α-stable emulsion for O was filtered through a 100-mesh wire mesh, and the nail Ji1. blood.

0 Mechanical Stability Emulsion 501 F'i Stable by Marlon method [ Stirred for 5 minutes at a rotational speed of 1000 rpm using a test machine under a load of C I U kg/an2, and all of the amount that did not pass through the 100 mesh wire mesh was stirred for 5 minutes. %fi O Polymerization rate relative to the polymer The total solids in the emulsion versus the theoretical solids weight.

0 grain diameter It was measured using a simple turbidity method.

of emulsion. ! Made by I'IJ Part 2> As a surfactant for emulsion polymerization, using the product of the present invention synthesized in Synthesis Example 1 and commercially available polyoxyethylene (41 sodium nonyl phenyl ether sulfate), styrene/medium 7 IJ rate, styrene/ethyl acrylate,
Then, a copolymerization reaction of medyl methacrylate/edyl 1 acrylate was carried out in the same manner as described above to obtain an emulsion. The surface tension, foaming properties, etc. of the emulsion were measured using the methods described above. The results are shown in Table 3.

Tables 2, 3, L: As is clear, synthetic comparative examples and t
Among the commercially available products, there are some that exhibit performance equivalent to or better than the products of the present invention in terms of mechanical stability, brightness, foaming, etc. of the prepared emulsions. However, they have surface tension, foaming property, polymerization stability, 1j14,
It is not possible to satisfy all mechanical stability requirements. Stiffness, versus 1. The product of the present invention can provide an emulsion that satisfies all of these requirements and has excellent physical properties.

Applicant's agent Kaoru Furutani

Claims (1)

[Claims] 1. The following two components (11 and (II)) (1) One or more V selected from the group consisting of unsaturated monomers containing a carboxyl group or a sulfonic acid group. Monomer and (b) Nisdel monomer of acrylic acid or -1/and methacrylic acid on aliphatic algol having 8 to 20 carbon atoms are combined (containing 60 or more dihydric acids as an essential component, component (I) and component αI) is 1[10, component (Il is 85 to 99 times Li, :CH, component CI+
1. A surfactant for emulsion polymerization, comprising a salt of a copolymer obtained by copolymerizing 1 to 15 layers. 2. The number average molecular end of the copolymer is j000 to 5000
Claim 1: 57, surfactant for emulsion polymerization of il+-, which is 0. 3. Ingredients (11 is acrylic acid, meccrylic acid, itaconic acid, 2-acrylamido-2-methylpropanesulfonic acid, methyl 1/allylsulfonate f!'&
The surfactant for emulsion polymerization according to claim 1 or 2, which is a monomer selected from the group consisting of , mecrylsulfonic acid, and vinylsulfonic acid.