JPS6220504A - Polymerizable composition of ambient temperature-curability - Google Patents

Abstract

PURPOSE:To provide a composition of outstanding ambient temperature- curability, capable of giving cured product free from discoloration with good appearance, comprising a vinyl monomer and redox polymerization initiator consisting of sulfoxyl acid salt compound and maleic acid hemiperester. CONSTITUTION:The objective composition comprising (A) a vinyl monomer (e.g., styrene, acrylonitrile, vinyl acetate) and (B) a redox polymerization initiator consisting of (i) sulfoxyl acid salt compound of, pref. formula I (M is alkali metal, or monovalent transistor metal; n is 0-5) or formula II (M is alkaline earth metal or divalent transition metal) (e.g., sodium formaldehyde sulfoxylate) and (ii) maleic acid hemiperester of, pref. formula III (R is saturated tertiary alkyl) (e.g., tertiary butylperoxy maleic acid).

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a cold-curable polymerizable composition of a vinyl compound containing a sulfoxylate compound and maleic acid hemiperester as a redox polymerization initiator.

Activation energy for decomposition is 25-40 Kcat/mo
The peroxide t is used alone as a radical polymerization initiator, but the peroxide f'Lv! - Generation of radicals becomes easier when used with a reducing agent.

A combination of such an oxidizing agent and a reducing agent is called a redox polymerization initiator, and is used for polymerization at low temperatures, and is used industrially for emulsion polymerization.

Redox polymerization is also used in the dental field, for example, cold-curable substances are used in the production of tooth filling materials (such as composite resins), tooth sealants and dental adhesives, caries prevention filling materials, dental crowns and dentures. It is used for manufacturing etc.

[Prior Art] Conventionally, the room-temperature-curing monopolymer composition utilized as described above includes a redox polymerization initiator using a combination of an organic peroxide and a tertiary amine, such as benzoyl peroxide and dimethyl p-toluidine. Compositions consisting of a redox polymerization initiator and a polymerizable ethylenically unsaturated substance are known, but materials using these redox polymerization initiators cure rapidly at room temperature, but the cured product is significantly colored. (Most of them are yellow) and have the disadvantage that they can only be obtained in large quantities and in water with a large change in color over time.

[Problem that the invention seeks to solve]

An object of the present invention is to solve the problems of the prior art described above, and to provide a room-temperature-curable polymerizable composition that immediately improves coloring and appearance properties and provides a cured product with no change in color tone over time.

[Friendly means of solving problems]

The room temperature curable polymerizable Mi bottom of the present invention is a room temperature curable polymerizable composition comprising a vinyl monomer and a redox 1 polymerization initiator, in which the redox polymerization initiator is composed of a sulfoxylate compound and a maleic acid hemiperester. It is characterized by being a combination.

The vinyl monomer forming the composition of the present invention may be a functional vinyl compound or a functional vinyl compound.

Examples of monofunctional vinyl compounds include styrene, acrylonitrile, vinyl acetate, methyl acrylate and methacrylate, ethyl acrylate and methacrylate, butyl acrylate and methacrylate, hydroxyethyl acrylate and methacrylate, methoxyethyl acrylate and methacrylate, glycidyl acrylate and methacrylate, Examples include methacryloxyethyl trimellitic acid and its acid anhydride. Examples of polyfunctional vinyl compounds include ethylene glycol represented by the following general formula (where RI is a hydrogen atom, RI is a methyl group, and p is an integer from 1 to 20). Diacrylates and methacrylates, diethylene glycol diacrylates and methacrylates, triethylene glycol diacrylates and methacrylates, polyethylene glycol diacrylates and methacrylates, 1,4-butanediol diacrylates and methacrylates, 1,3-butanediol diacrylates and methacrylates, 1 .6-hexanediol diacrylate and methacrylate, glycerin diacrylate and methacrylate, and bisphenol represented by the following general formula (wherein, Rf represents a hydrogen atom or a methyl group, and p is an integer from 1 to 20). A
Examples include diglycidyl acrylate and methacrylates, urethane diacrylate and methacrylates, trimethylolpropane triacrylate and methacrylate, pentaerythritol tetraacrylate and methacrylate, bisphenol A diacrylate and methacrylate, and the like. Even if one type of these acrylates and methacrylates is used, two
You may use combinations of more than one species.

The sulfoxylate compound used as the redox polymerization initiator of the present invention preferably has the following general formula % (where M is an alkali metal atom and n is a monovalent transition metal atom, and n is a monovalent transition metal atom). A formaldehyde derivative of a sulfoxylate represented by n, a natural number r from 0 to 5. represents a natural number from 0 to 5), and particularly preferred are sodium formaldehyde sulfoxylate, zinc formaldehyde sulfoxylate, and the like.

All maleic acid hemiperesters can be applied, but
Particularly preferred is tertiary butyl peroxymaleic acid. These redox polymerization initiators are
104 for the vinyl monomer mentioned above! ii%~30
% by weight, preferably 10-” li (% by weight ~ 2Of
It is added in an amount of I, particularly preferably in an amount of 10-1 to 10% by weight.The amount of maleic acid hemiperester to be added is IAQ~1 in weight ratio to the sulfoxylate compound.
It is in the range of 0/1. This formulation 1i is suitable for obtaining a composition with no coloration or change in color tone over time of the polymerized cured product and furthermore having high mechanical strength.

In the composition of the present invention, fillers may be added to the above-mentioned components if necessary. Such filler components include those listed in Periodic Law No. 1. n, III.

Oxides and hydroxides of group ■, group ■, transition metals, and seven groups,
Examples include chlorides, sulfates, sulfites, carbonates, phosphates, silicates, and mixtures and complex salts of these, among which silica dioxide, quartz powder, aluminum oxide, and sulfuric acid. Preferred are barium, titanium oxide, talc, glass powder, glass peas, glass fiber, barium salt, glass filler containing lead salt, silica gel, colloidal silica, carbon fiber, zirconium oxide, tin oxide, and other ceramic powders. .

The above-mentioned filler may be any of untreated filler, surface-treated filler using a silane coupling agent, etc., and organic composite filler composited with a polymer and pulverized. The blending amount of these fillers can be changed as appropriate depending on the purpose of use of the room-temperature polymerized cured product, but for example, when used as an optical filler for dental materials, 1 to 10% of the above vinyl monomer is used. 103% by weight, preferably 10~? ,
5 x 10 Tomiju 1 inch, particularly preferably 20~? ,
Composition 1 of the present invention can be used as a paste composition by blending in an amount of 0x1G"3i, and when storage stability of the blended paste is required: It can be used by dividing it into two parts, blending the sulfoxylate compound into one half, and blending maleic acid hemiperester into the other.

Furthermore, the composition of the present invention may optionally contain a colorant, a polymerization inhibitor (e.g., hydroquinone, methoxybenzophenone, methylphenol, hydroquinone 7-methyl ether, etc.), an oxidation stabilizer, and an ultraviolet absorber (e.g., benzophenone, etc.). , pigments (e.g. iron oxide, titanium oxide, etc.)
, dyes, etc. can also be blended.

〔Example〕

Next, the present invention will be explained in more detail with reference to examples, but the present invention is not limited to these examples.

Examples 1-2. A monomer mixture consisting of Comparative Examples 1 to 2 and the following monomer mixture (3%, monomer) were quickly blended at room temperature (20°C), and then the mixture was sealed on the bottom side. Teflon cylinder (inner diameter 4
Pour the mixture into a tube (height: 20 mm) until the upper liquid level matches the top surface of the Teflon tube, and leave it in that state for 10 minutes to perform room temperature polymerization. After that, remove the reactant from the Teflon tube.
It is clear from Table 1 that the composition according to the present invention has excellent room-temperature curing performance of A or L compared to the composition of the comparative example, and can be cured to form a polymer without coloration. I understand.

Examples 3-4. Comparative Examples 3 to 4 A monomer/filler mixture (paste) and the following monomer/filler mixture and gold were quickly blended at room temperature (20°C), and then the mixture paste (H lower surface sealed n72: Teflon tube) (Circle diameter: 4 mm, height: 20 mm) until the upper paste side is flush with the top surface of the Teflon tube, and leave it in that state for 10 minutes to carry out the complete polymerization at room temperature.Then, remove the reactant from the Teflon tube. The appearance, etc. of the obtained n-9 polymerized cured product was evaluated.

Table 2 shows the type and amount of the sulfoxylate compound and the above-mentioned cured appearance evaluation results.

Table 2> As is clear from Table 2, even when a filler is added, the composition according to the present invention has excellent room temperature curing performance compared to the composition of the comparative example, and the cured product has no coloration. It turns out that

Example 5. Comparative Example 5 Color tone change of the cured products according to Examples 5 to 4 and the cured products according to Comparative Example 3 after a one-week exposure test with sunlight, and 60 ° C.
The color change 'k fill' after a one-week immersion test in water was determined and shown in Table 3.

Table 3 As is clear from Table 3, it can be seen that the composition according to the present invention has extremely high color stability compared to the composition of Comparative Example 3. For those who use a redox polymerization initiator consisting of a sulfoxylate compound and maleic acid hemiperester, the composition can be used in place of a conventional polymerization initiator consisting of M peroxide and tertiary amine. In comparison, it is possible to obtain a cured product that has excellent curing performance at room temperature and also has excellent appearance performance with no coloring.

Claims (1)

[Claims] 1. A cold-curing polymerizable composition comprising a vinyl monomer and a redox polymerization initiator, characterized in that the redox polymerization initiator is a combination of a sulfoxylate compound and a maleic acid hemivar ester. A room temperature curing polymerizable composition. 2. In addition to the vinyl monomer and redox polymerization initiator,
The room temperature curable polymerizable composition according to claim 1, further comprising a filler. 3. The sulfoxylate compound is a sulfoxylic acid represented by the general formula MHSO_2・CH_2O・nH_2O (wherein M represents an alkali metal atom or a monovalent transition metal atom, and n represents a natural number from 0 to 5). Formaldehyde derivatives of salts or sulfoxylates represented by the general formula MSO_2・CH_2O・nH_2O (wherein M represents an alkaline earth metal atom or a divalent transition metal atom, and n represents a natural number from 0 to 5) The room temperature curable polymerizable composition according to claim 1 or 2, which is a formaldehyde derivative of. 4. Claim 1, wherein the maleic acid hemiperester is represented by the general formula ▲ Numerical formula, chemical formula, table, etc. ▼ (In the formula, R represents a saturated tertiary alkyl group); or 2. Room-temperature curing polymerizable composition according to item 2. 5. The cold-curing polymerizable composition according to claim 1, 2 or 3, wherein the sulfoxylate compound is sodium formaldehyde sulfoxylate or zinc formaldehyde sulfoxylate. 6. The room temperature curable polymerizable composition according to claim 1, 2 or 4, wherein the maleic acid hemiperester is tertiary butyl peroxymaleic acid.