JPS6183201A - Fine resin particle having function of improving quality - Google Patents

Abstract

PURPOSE:The title fine resin particles which can give a film excellent in heat resistance, softening resistance, blocking resistance, weather resistance, etc., having a specified weight change in differential thermogravimetry and a specified particle diameter. CONSTITUTION:An ethylenically unsaturated monomer [e.g., methyl (meth) acrylate] is suspension-copolymerized or emulsion-copolymerized with a mono mer having at least two radical-polymerizable ethylenically unsaturated bonds in the molecule (e.g., ethylene glycol diacrylate) and/or two ethylenically- unsaturated monomers each having a group reactive with each other (e.g., glycidyl acrylate and acrylic acid) to obtain fine resin particles comprising a (co)polymer of a polymerizable ethylenically unsaturated group-containing monomer, having a maximum peak temperature of a weight change obtained when a sample is heated at a constant rate of temperature rise in differential thermogravimetry >=380 deg.C and a particle diameter of 0.01-6mu.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to minute resin particles having a quality improving function. The fine resin particles of the present invention can improve performance such as heat resistance, softening resistance, blocking resistance, weather resistance, etc. by adding them to paints and plastic products.

Background Techniques, Techniques and 4 Problems - As a method to improve the softening resistance and heat resistance of paints, plastic films, etc. without changing the resin composition, extender pigments and inorganic fillers are used. There are ways to add . However, when a large amount of these inorganic powders is added, problems such as a decrease in mechanical strength, a decrease in gloss, and a decrease in weather resistance occur. It is conceivable to change the composition of the resin itself and use it in paints, etc., but this would be impractical as it would reduce solubility and workability.

゛ The present invention provides fine resin particles that have the function of improving the heat resistance, softening resistance, blocking resistance, and weather resistance of the entire coating film by, for example, adding it to conventional paint components. With the goal.

Solution method The present invention provides micro resin particles with a particle size of o, 01 to 6μ, which are made of a polymer or copolymer of a monomer having a polymerizable ethylenically unsaturated group, and the sample is kept constant in differential thermogravimetry. To provide micro resin particles having a quality improvement function, characterized in that the maximum peak temperature of weight change when heated at a temperature increase rate of 380°C or higher.

When the fine resin particles of the present invention are added to paints, plastic films, etc., they improve their properties such as heat resistance, softening resistance, blocking resistance, and weather resistance. However, unlike inorganic substances, it is strongly bonded to the surrounding matrix resin in the coating film, etc., without reducing the overall mechanical strength, and without impairing the appearance such as gloss and transparency. Furthermore, since they are fine particles, they mix uniformly with the matrix resin, which actually improves workability, such as paint sagging performance.

The fine resin particles of the present invention are measured by differential thermogravimetry (hereinafter referred to as r D T ) as one of the thermochemical parameters.
When a sample is heated at a constant rate of temperature increase, e.g. 20°C per minute, at a temperature of (hereinafter referred to as rDpJ) is 380°C or higher. CJ, thermogravimetry (TG), differential thermogravimetry (r)T are methods for measuring the thermochemical behavior of substances.
O), differential thermal analysis (+)TA), etc., but the evaluation of the thermochemical performance improvement function of the fine particles of the present invention is based on the above-mentioned D.
This is possible by using p as a parameter. D.I.
) is measured using a commercially available simultaneous differential thermogravimetric measuring device, such as Model 5SC1560GI+ manufactured by Dai-ni Okosha Co., Ltd.
Sample 10 was taken and heated from 30°C to 550°C at a rate of 20°C per minute, and from the DTG graph l)
p can be easily determined.

If Dp is large, there will be less loss of M due to depolymerization of the resin particles, and the resin particles will be heat resistant, and even if the resin particles are exposed to high temperatures, they will not be easily damaged by heat such as softening, deterioration, decomposition, and evaporation.

Therefore, when such resin particles are added to paints, plastic films, etc., the overall thermochemical performance is improved.

Booklet - Applications Various methods have been proposed to produce microscopic fat particles, one of which involves mixing an ethylenically unsaturated monomer with a crosslinkable comonomer in an aqueous medium. A dispersion of fine resin particles is created by suspension polymerization or emulsion polymerization, and water is removed by solvent substitution, azeotropy, centrifugation, drying, etc. to obtain fine resin particles. Copolymerize an ethylenically unsaturated monomer with a crosslinkable comonomer in a non-aqueous organic solvent that dissolves monomers such as hydrocarbons but does not dissolve the polymer, and disperse the resulting fine resin particle copolymer. This is a method called the NAD method.

The fine resin particles of the present invention may be produced by any of the above methods. The method for producing microparticles using a water-soluble resin having an amphoteric group described in JP-A-58-129066 by the present inventors may also be used. From the viewpoint of reactivity and storage stability, it is necessary that the thickness be 0.01 to 6μ.

Examples of ethylenically unsaturated monomers include methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate. Alkyl esters of acrylic acid or methacrylic acid and other monomers having ethylenically unsaturated bonds that can be copolymerized with them, such as styrene, α-methylstyrene, vinyltoluene, t-
Examples include butylstyrene, ethylene, propylone, hinyl acetate, vinyl propionate, acrylonitrile, methacrylonitrile, and dimethylaminoethyl (meth)acrylate. Two or more types of these intermediates may be used.

Crosslinkable copolymer bodies are monomers and/or monomers having two or more radically polymerizable ethylenically unsaturated bonds in the molecule.
Alternatively, it contains two types of ethylenically unsaturated group-containing monomers each carrying groups that can react with each other.

Examples of monomers having two or more radically polymerizable ethylenically unsaturated groups in the molecule include polymerizable unsaturated monocarboxylic acid esters of polyhydric alcohols and polymerizable unsaturated alcohol esters of polybasic acids. , and aromatic compounds substituted with two or more vinyl groups, examples of which include the following compounds.

Ethylene glycol diacrylate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate l/-
1,3-butylene glycol dimethacrylate, trimethylolpropane 1-reacrylate, trimethylolpropane trimethacrylate, 1,4-butanediol diacrylate, neopentyl glycol diacrylate, 1,6-hexanediol diacrylate, penta Erythritol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, pentaerythritol dimethacrylate,
Pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, glycerol dimethacrylate, glycerol diacrylate, glycerol allyloxy dimethacrylate, 1,1.1-trishydroxymethylethane diacrylate, 1,1.1
-trishydroxymethylethane triacrylate, 1
, 1.1-1-lishydroxymethylethane dimethacrylate, LLI-1-lishydroxymethylethane trimethacrylate, 1. ．． 1.1-Trishydroxymethylpropane diacrylate, 1,1.1-) Lishydroxymethylpropane [reacrylate, 1. L
l-1-lishydroxymethylpropane dimethacrylate, 1,L'l-1-lishydroxymethylpropane trimethacrylate, triallyl cyanurate], triallyl isocyanurate, triallyl trimellitate,
Diallyl terephthalate, diallyl phthalate and divinylhenzene.

In addition, examples of monomers having two types of ethylenically unsaturated groups each carrying mutually reactive groups include epoxy group-containing ethylenically unsaturated monomers such as glycidyl acrylate and glycidyl methacrylate, and acrylic acid and methacrylic acid. The most typical examples are carboxyl group-containing ethylenically unsaturated polymers such as acid and crotonic acid, but mutually reactive groups are not limited to these.
For example, various compounds have been proposed, such as amine and carbonyl, epoxide and carboxylic acid anhydride, amine and carboxylic acid chloride, alkyleneimine and carbonyl, organoalkoxysilane and carboxyl, hydroxyl and isocyanate, etc., and the present invention broadly encompasses these. It is something to do.

・Minute resin particles produced in an aqueous medium or a non-aqueous organic medium can be used as is, but they can be isolated by a method such as filtration, spray drying, or freeze drying, and then used as is or by milling, etc. It can also be used by pulverizing it to an appropriate particle size using a method, or it can be used by replacing the medium with a synthesized dispersion liquid by solvent replacement.

In order to control the Dp of the fine resin particles obtained in this way, it is sufficient to cause the fine resin particles to have a three-dimensional structure due to internal crosslinking. Methods for producing a three-dimensional structure include the use of crosslinkable comonomers during the synthesis of resin particles as described above, and the use of two or more monomers carrying groups capable of crosslinking with each other. There are two methods: a method of synthesizing fine resin particles using powder, self-crosslinking by heat treatment after powdering, and a method of using these in combination. The amount of crosslinkable copolymerizable monomers or monomers that can crosslink with each other varies depending on the type of specific monomer used, the polymerization method, etc., but is generally 3% or more of the weight of the fine resin particles. should account for

The fine resin particles of the present invention may have a homogeneous structure or may have a multilayer structure such as a core/shell structure. In the case of a multilayer structure, the op of the resin constituting at least one layer must be 380° C. or higher.

Heretofore, there has been no known satisfactory method of enhancing the thermochemical performance of a paint without substantially affecting its other properties with additives. The fine resin particles of the present invention can achieve this purpose, and can be used not only in the paint field, but also in plastic films, adhesives, sealants, etc., and have excellent softening resistance, blocking resistance, and Scratch resistance etc. can be improved.

The present invention will be explained in more detail with reference to Examples below. "1 part" and "%" in the examples are based on weight.

Reference example 1 Bishydroxyethyl taurine 13
4 parts, 130 parts of neopentyl glycol, 236 parts of azelaic acid, 186 parts of phthalic anhydride and 27 parts of xylene were charged, and the temperature was raised. Water produced by the reaction is azeotroped with xylene and removed.

The temperature was raised to 190°C over about 2 hours from the start of refluxing, stirring and dehydration were continued until the acid value equivalent to carboxylic acid reached 145, and then the mixture was cooled to 140°C.

Next, the temperature was maintained at 140°C, and "Cardura E10"
314 parts of persatic acid glycidyl ester (manufactured by Shell) were added dropwise over 30 minutes, and stirring was continued for 2 hours to complete the reaction. The resulting I polyester resin has an acid value of 59. Hydroxyl value 90,
It was M stone 1054.

Reference Example 2 Preparation of a J-suspension emulsifying agent with 1 base per side on both sides Using the same apparatus as in Reference Example 1, sodium salt of taurine 73.
Add 5 parts of ethylene glycol, 400 parts of ethylene glycol, and 200 seconds of ethylene glycol monomethyl ether, and heat while stirring to bring the temperature to 120°C. After the contents reached a uniform state of dissolution, Epicor) 1001 (manufactured by Shell Chemical Company, diglycidyl ether type epoxy resin of bisphenol A) was added.

A solution consisting of 470 parts of epoxy equivalent (470 parts) and 400 parts of ethylene glycol monomethyl ether was added dropwise over 2 hours. After dropping, stirring and heating were continued for 20 hours to complete the reaction. The reaction product is purified and dried in the same manner as in Reference Example 1 to obtain 518 parts of a modified epoxy resin.

The acid value c of this resin by KOH titration was 149.4,
The sulfur content by fluorescent X-ray analysis was 2.8%.

Example 1 17! equipped with a stirrer, cooler, and temperature control device! In a reaction vessel, 380 parts of deionized water, 50 parts of the emulsifier having amphoteric ionic group obtained in Reference Example 1, and 7 parts of dimethylethanolamine were charged, and dissolved while stirring at a temperature of 80°C.
Add 2.5 parts of azobiscyanovaleric acid to this and 50 parts of deionized water.
1 part and a solution dissolved in 1.6 parts of dimethylethanolamine,
A mixed solution consisting of 118 parts of styrene, 118 parts of ethylene glycol dimethacrylate, and 14 parts of 2-hydroxyethyl acrylate was added dropwise over 90 minutes.
After that, stirring was continued for another 90 minutes, and the non-volatile content was 43%.
An aqueous dispersion of fine resin particles having an average particle diameter of 45 mμ was obtained. By freeze-drying a portion of this fine resin dispersion, fine resin particle powder could be obtained.

The minute resin powder was measured using a differential thermogravimetric simultaneous measuring device (5S).
Thermal analysis was carried out using C1560G)I @Daini Seikokin Co., Ltd.). Figure 1 shows the chart obtained, but DT
The temperature Dp at which G reaches its maximum is 396'C and 441°C.
Two values were shown.

Comparative Example 1 Polymerization was carried out in the same manner as in Example 1 except that 118 parts of methyl methacrylate was used instead of 118 parts of ethylene glycol dimethacrylate, and the non-volatile content was 43% and the average particle size was A fine resin particle dispersion liquid of 48 mμ was obtained. Similarly, fine resin particle powder was obtained by freeze-trying the fine resin dispersion. The results of measurement of this fine resin powder using a simultaneous differential thermogravimetric measurement device are shown in FIG. The Dp of the minute resin particles is 3
The temperature was 56°C.

Example 2 370 parts of deionized water, 40 parts of the emulsifier having a zwitterionic group obtained in Reference Example 2, and 3 parts of dimethylethanolamine were charged into 11 reaction vessels equipped with a stirrer, a cooler, and a temperature control device, and the mixture was stirred. The solution is dissolved while maintaining the lower temperature at 80° C., and a solution prepared by dissolving 4.5 parts of azobiscyanovaleric acid in 45 parts of deionized water and 4.3 parts of dimethylethanolamine is added thereto.

Next, 60 parts of styrene, 60 parts of methyl methacrylate,
A liquid mixture consisting of 90 parts of n-butyl acrylate, 5 parts of 2-hydroxyethyl acrylate, and 25 parts of ethylene glycol dimethacrylate was added dropwise over 60 minutes. After the dropwise addition, a solution of 1.5 parts of azobiscyanovaleric acid dissolved in 15 parts of deionized water and 1.4 parts of dimethylethanolamine was added, and stirring was continued at 80°C for 60 minutes until the non-volatile content was 39% and the particle size was 50 mμ. An aqueous dispersion of minute resin particles was obtained. A fine resin powder could be obtained by spray drying a portion of this resin.

The Dp of such fine resin particles was 385°C.

Example 3 After charging 1000 parts of deionized water, 20 parts of polyvinyl alcohol with an average molecular weight of -1500, and 10 parts of sodium dodecylhenzenesulfonate into a 1ρ reaction vessel equipped with a stirrer, a cooler, and a temperature control device, ]000 rpm. 10 parts of styrene and 1 to 30 parts of methyl methacrylate were heated to 60°C while stirring and thoroughly parsed with N2 gas.
10 parts of ethylene glycol dimethacrylate and 1 part of 2.2''-azobis-(2,4-dimethylvaleronitrile) (trade name V-65. 2 polymerization initiator manufactured by Wako Pure Chemical Industries EL) were stirred. The resulting mixture was added dropwise over 1 hour. After the completion of the addition, the temperature inside the reaction vessel was raised by 70° C., and the reaction was continued for an additional 5 hours to obtain fine resin particle powder with an average particle size of 5.5 meters.

The Dp of this fine resin particle powder was 390°C.

Example 4 800 parts of deionized water was added to a 1P reaction vessel equipped with a stirrer, a cooler, and a temperature control device, and the temperature was raised and maintained at 80°C while stirring and thoroughly purging with N2 gas. 1/2 of an aqueous solution in which 2 parts of ammonium persulfate was dissolved in 100 parts of deionized water, 88.6 parts of methyl methacrylate, 1-7.1 parts of glycidyl methacrylate, and 4.3 parts of methacrylic acid. 1150 of the monomer mixture consisting of the following was added dropwise, and after the apparatus was left for 10 minutes, the remaining ammonium persulfate aqueous solution 1/20 and the monomer mixture 49150 were simultaneously added dropwise over 1 hour. After the dropwise addition was completed, stirring was continued for 1 hour, and the average particle size was 0.6μ and the non-volatile content was 9.9%.
A fine resin particle dispersion was obtained. The resin dispersion was separated into a supernatant and fine resin particles by centrifugation. By repeating the process of dispersing the resin particles in deionized water and then centrifuging them three times, the resulting fine resin particle slurry was air-dried and then heat-treated at 150°C for 10 hours to achieve internal three-dimensional crosslinking. We were able to obtain fine resin particles. The Dp of the tiny resin particles is 40
There were 2 cities.

Example 5 11.6 parts of the fine resin particle dispersion obtained in Example 1 were added with 181 parts of Brimar AC-1533 (acrylic emulsion resin manufactured by Rohm and Haas) and Cymer 303 (methylated melamine manufactured by Nippon Cyanamid Co., Ltd.). resin)
A clear resin composition was obtained by mixing 15 parts. A film was obtained by applying this composition to a chemical conversion treated board using a buff coater to a film thickness of 20 μm and baking it at 170° C. for 20 minutes. The hardness of this film at 80° C. was F. The gloss retention rate after being left at a high temperature of 200°C for 20 hours was 58%.

Comparative Example 2 The resin composition of Example 5, which did not contain minute resin particles, was tested in exactly the same manner as in Example 5, and the hardness of the film at 80'c was 2B. The gloss retention rate after being left at a high temperature of 200° C. for 20 hours was 34%.

[Brief explanation of the drawing]

FIG. 1 is a thermal analysis chart of the fine resin particles obtained in Example 1 using a differential thermogravimetric simultaneous measuring device, and FIG. 2 is a thermal analysis chart of the fine resin particles of Comparative Example 1. Figure 1 Figure 2

Claims (2)

[Claims] (1) Micro resin particles with a particle size of 0.01 to 6μ made of a polymer or copolymer of a monomer having a polymerizable ethylenically unsaturated group, in which a sample is heated at a constant temperature in differential thermogravimetry. 1. Micro resin particles having a quality improvement function, characterized in that the maximum peak temperature of weight change when heated at a high speed is 380° C. or higher. (2) At least some of the monomers having a polymerizable ethylenically unsaturated group can crosslink with monomers having two or more radically polymerizable ethylenically unsaturated bonds in the molecule and/or with each other. 1. The fine resin particles of item 1, which contain two or more ethylenically unsaturated monomers carrying groups.