JPS62179505A - Production of fine polymer particle - Google Patents

Abstract

PURPOSE:To produce fine monodisperse polymer particles having a large particle diameter and a narrow particle diameter distribution, by polymerizing a vinyl monomer in an aqueous medium in the presence of a polymerization initiator, a specified succinate derivative and a metal sulfate. CONSTITUTION:100pts.wt. vinyl monomer (e.g., styrene) is mixed with 0.01-100 pts.wt. succinate derivative of formula I or II [wherein R1-4 are each a 2-20C alkyl which may contain a polymerizable double bond, an (un)saturated phenyl or an (unsubstituted) cyclohexyl], a water-soluble polymerization initiator (e.g., K2S2O8) in an amount to provide a concentration in an aqueous medium >=4X10<-3>mol/1, 10<-4>-10<-1>mol, per mol of the polymerization initiator, of a metal sulfate (e.g., CuSO4 and 150-2,000pts.wt. aqueous medium. The mixture is polymerized at 40-80 deg.C to obtain fine polymer particles of a particle diameter of 1.0-10.0mu.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for producing fine emulsion polymer particles, and more particularly to a method for producing fine emulsion polymer particles having a relatively large particle size.

BACKGROUND ART Conventionally, methods for increasing the particle size of polymer fine particles obtained in emulsion polymerization include (1) reducing the amount of emulsifier, (2) reducing the amount of polymerization initiator, and (3) It is known to add an inorganic electrolyte. These methods reduce emulsion polymerization stability;
Further, even if polymer fine particles with a large particle size can be obtained, they have drawbacks such as polydispersity in particle size. As a means to improve these drawbacks, for example, Japanese Patent Application Laid-Open No. 59-2
As described in 2904@publication, the method for controlling the concentration of inorganic electrolyte or the Polymer Science Society of Japan Proceedings Volume 1
．． As described in No. 34, a method for obtaining a latex of a styrene-acrylamide copolymer using a solvent in combination with water has been proposed.

Problems to be Solved by the Invention However, in the method of controlling the concentration of the inorganic electrolyte described above, particles with a particle size of 1 μm or more cannot be obtained. In addition, the method of obtaining latex of styrene-acrylamide copolymer using a solvent in combination with water can obtain particles with a particle size of 1μ or more, but there is a limit to the monomer used for polymerization, and it is not suitable for a wide variety of applications. It was something I couldn't handle.

In view of the above J: eel situation, the present inventors have determined that particle size 1
As a result of intensive research into a method for producing polymer particles with a particle size larger than μ and an extremely narrow particle size distribution.

The present invention has now been completed.

Therefore, an object of the present invention is to provide a method for producing monodisperse polymer fine particles having a large particle size and an extremely narrow particle size distribution.

Another object of the present invention is to provide a method for producing fine polymer particles without major restrictions on the type of monomer used as a raw material.

Means and Effects for Solving the Problems These objects of the present invention are to prepare a vinyl monomer in an aqueous medium with a polymerization initiator, a succinate ester derivative represented by the following general formula (I), and a metal. This is achieved by a method for producing fine polymer particles characterized by polymerization in the presence of sulfate.

Na5O3-CH-COOR1 1 (■) NaSO3CH-COOR2 (R1, R2, R3 and R4 each have 2 to 2 carbon atoms
0 alkyl group, substituted or unsubstituted phenyl group, substituted or unsubstituted cyclohexyl group, which may contain a polymerizable double bond, and R1, R2, R3 and R
4 may be the same or different. ) Conventionally, in emulsion polymerization, when a dispersant having a relatively low interfacial tension with respect to a monomer having a long-chain hydrophobic group is used, the polymer fine particles obtained by emulsion polymerization are
Only fine polymer particles with a small particle size of approximately 0.1 to 0.5μ can be obtained, and conversely, when a dispersant having a relatively high interfacial tension with respect to the monomer is used, it is difficult to obtain fine particles. The particle size of the polymer fine particles obtained is approximately 0.7 to 4μ, which is large, but the monodispersity becomes poor and it is difficult to obtain 1 q of polymer fine particles with a uniform particle size. .

However, in the present invention, by using the succinic acid derivative ester represented by the general formula (I), which is a dispersant having a relatively high interfacial tension, together with a metal sulfate during polymerization, the interfacial tension is approximately 1.0 to 10. It was possible to obtain monodisperse polymer fine particles having a large particle size of 0μ and an extremely narrow particle size distribution.

Amber r! is a must for dispersants with relatively high interfacial tension! li
By using a derivative ester and a metal sulfate during polymerization, it is possible to obtain large particle size and
Although it is not clear whether monodisperse polymer fine particles are affected by the electrolyte, it is probably due to the electrolyte properties of the metal sulfate, that is, the property of maintaining the stability of the surface charge of the monomer in the vicinity of the monomer surface. In addition, the properties of the metal FIIt salt as a polymerization accelerator and the succinate ester derivative as a dispersant have a synergistic effect in some way, resulting in a large particle size and monodisperse polymer. It is assumed that fine particles are generated. In any case, in the emulsion polymerization method of the present invention, fine polymer particles with a particle size of 1.0 to 10.0μ and a narrow particle size distribution can be obtained through a simple process without going through a complicated polymerization process. It's amazing what happens.

The succinic acid derivative ester represented by the general formula (I>) used in the present invention plays a role as a dispersion stabilizer for succinic acid, and the amount added depends on the vinyl monomer used. 0.01 per 100 mass
It is used in a range of 100 parts by weight, preferably 0.1 to 4 parts by weight. If the amount added is more than 10 parts by weight, the particle size of 1q polymer particles becomes too small, and if it is less than 0.011 parts by weight, the particle size distribution of the fine polymer particles becomes wide, resulting in monodispersity. becomes worse.

In the present invention, in addition to the above-mentioned succinic acid ester derivative, other known dispersion stabilizers may be used as necessary, such as
Polycarboxylic acids and naphthalenesulfonic acid formalin condensates may also be used.

The gold sulfur M salt used in the present invention is an electrolyte and exhibits properties as a polymerization accelerator, and specifically, CuSO4, CU2S041. FeSO4,
Fe2(SO4>3, NaH) can also be used. However, it is particularly preferred to use copper sulfate, ferric sulfate.

The above metal @acid salt is 10-4 per mole of polymerization initiator.
It is preferable to use it in a range of mol to 10-1 mol. 10-4
If the amount is less than 1 mole, the polymerization becomes unstable and aggregates are likely to occur.On the other hand, if the amount is more than 10-1 mole, the decomposition rate of the polymerization initiator becomes too fast, which is dangerous. At the same time, the monodispersity of the resulting polymer particles deteriorates.

The polymerization initiator in the present invention is not particularly limited as long as it is water-soluble, but persulfates such as potassium persulfate and ammonium persulfate are mainly used. These polymerization initiators are preferably used at a concentration of 1×10 −3 mol/l or more, more preferably 48.103 mol/l or more in terms of concentration in the aqueous medium used during polymerization. If the concentration is low at the @ end, phenomena such as decreased particle size and non-uniform particle size of the obtained polymer particles may occur.

Vinyl AAAs that can be used in the present invention include:
There are no particular limitations, but examples include vinyl aromatic compounds such as styrene, methylstyrene, and helosyrene, methyl methacrylate, n-butyl methacrylate, and 2-acrylic acid.
Acrylic monomers such as ethylhexyl, glycidyl methacrylate, acrylamide, fluorinated acrylic monomers such as perfluoroacrylate, nitrile monomers such as acrylonitrile and methacrylate, ethylenically unsaturated monoolefins such as ethylene propylene, etc. can give. Further, polyfunctional monomers such as divinylbenzene and diethylene glycol methacrylate can also be used if necessary.

Water is mainly used as the aqueous medium, and the amount used is 150 to 2,000 parts by weight, preferably 200 to 1,000 parts by weight, per 100 parts by weight of 7-mer. Although the polymerization temperature can be set arbitrarily, it is usually preferably in the range of 40 to 80°C.

Effects of the Invention According to the method for producing fine polymer particles of the present invention, emulsion polymerization produces polymer particles with extremely large particle diameters of about 1.0 μm to 10.0 μm and narrow particle size distribution (monodisperse). can be easily obtained without the need for complicated processes.

According to the present invention, there are no major restrictions on the monomer species used during polymerization, and it is also possible to obtain core-shell structured polymer particles. It can be applied to enzyme carriers, immunoserological diagnostic agent carriers, pharmaceutical administration carriers, ion exchange resins, crystal display spacers, column packing materials, electrophotographic developers, paints, etc.

Embodiments All the embodiments of the present invention are equipped with a 5,1! It was carried out in a glass-lined autoclave.

Example 1 Distilled water 3.2.1! was placed in a reactor and the atmosphere was replaced with nitrogen gas. Afterwards, the temperature was raised to 50°C. To this was added an aqueous solution in which 5.6 g of the following compound was dissolved in 0.241 g of water, and then 28.89 g of ammonium persulfate was dissolved in 0.2.1 g of water. of water was added. Additionally, 200m of styrene and 0.2g of copper sulfate
was added and polymerized for 4 hours while maintaining the polymerization temperature at 50°C. Next, a mixed solution of 160 rIdl of styrene and 20d of perfluoromethacrylate was put into the dropping funnel, and about 2
It dripped in time. The polymerization was further continued and completed in a total of 26 hours. When the particle size of the obtained polymer fine particles was observed using a scanning electron microscope, it was found to be 2.0.
It was found that the particles were composed of almost monodisperse particle aggregates of μ.

The latex was exfoliated and lyophilized. Thereafter, it was ground with a pin mill and tested as an external additive for electrophotographic developers, and it was confirmed that it was effective as a charging aid and a cleaning aid.

Example 2 After 200 m of styrene was mixed for 4 hours in the same manner as in Example 1, 140 m of styrene and 60 m of glycidyl methacrylate were added dropwise to complete the polymerization.

However, 4.89% of the following compound was used as a dispersion stabilizer.

When the obtained polymer fine particles were examined using a scanning electron microscope, it was found that the particle size was 4 μm and almost monodisperse.

When this latex was subjected to immunological tests as a protein trade immobilization carrier, it showed good properties as a carrier.

Comparative Example 1 Polymerization was carried out in the same manner as in Example 1 except that the dispersant was changed to polycarboxylic acid (Demol-P manufactured by Naeto).

The obtained polymer fine particles had a polydisperse particle size of 0.3 to 3.8μ, and the recovery rate was low.

Comparative Example 2 When polymerization was carried out in Example 1 by changing the dispersing agent to sodium dodecyl Wt acid, the obtained polymer fine particles were monodisperse, but the particle size was as small as 0.35μ.

Patent Applicant Fuji Xerox Co., Ltd. Agent Patent Attorney Tsuyoshi Horabe Procedural Amendment (Voluntary) March 7, 1985 Commissioner of the Japan Patent Office Ubuya Michibu Membrane Office 3-3-5 Akasaka, Minato-ku, Tokyo Name (
549) Yota Kobayashi, Representative of Fuji Pilots Co., Ltd. Column 7 of ``Comprehensive Explanation of I Defense'' Contents of Amendment (1) The scope of the claims is amended as shown in the attached sheet.

(2) "General formula (■>)" in the second line of page 5 of the specification is corrected to 1 general formula (I> or (■)).

(3) Insert the following chemical structural formula below the chemical structural formula on page 5, line 6.

(4) Delete "having a long-chain hydrophobic group" from lines 4 to 3 from the bottom of page 5.

(5) On page 6, line 20, "monomer" is corrected to "emulsion particles."

(6) 10.01 to 100 parts by weight on page 7, line 14.”
io, 01 to 10 parts by weight".

(7) On page 8, line 3, ``use of formalin condensate'' is corrected to ``combined with formalin condensate, etc.''.

(8) The chemical structural formula on page 11, line 8 is corrected as follows.

(9) The chemical structural formula on page 12, line 12 is corrected as follows.

(Attachment) 2. Claims (1) Vinyl monomers are treated in an aqueous medium with a polymerization initiator,
A method for producing fine polymer particles, which comprises polymerizing in the presence of a succinate ester derivative represented by the following general formula (I) or (II) and metal 6j [salt].

NaSO3CHGOORl l (■) NaSO3CHC00R2 NaSO3CHC00R3 1 (■) CH-COOR4 (RRR and R4 are each an alkyl group having 2 to 20 carbon atoms, a substituted or unsubstituted phenyl group, a substituted or unsubstituted cyclohegycyl group and may contain a polymerizable double bond, and R1, R2, R3,
R4 may be the same or different. ) (2) The concentration of the polymerization initiator in the aqueous medium is 4×'! 0
1. A method for producing polymer fine particles according to claim 1, wherein the polymer particles have a mol/N or more.

Claims (2)

[Claims] (1) A vinyl monomer is added to a polymerization initiator in an aqueous medium,
A method for producing fine polymer particles, which comprises polymerizing in the presence of a succinate ester derivative represented by the following general formula (I) and a metal sulfate. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (I) (R_1, R_2, R_3 and R_4 are each an alkyl group having 2 to 20 carbon atoms, a substituted or unsubstituted phenyl group,
Substituted or unsubstituted cyclohexyl group, polymerizable 2
May contain a double bond, and R_1, R_2,
R_3 and R_4 may be the same or different. ) (2) The concentration of the polymerization initiator in the aqueous medium is 4 x 10^-
^3 mol/l or more, the method for producing polymer fine particles according to claim 1.