JPS638126B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention provides a novel crosslinked polymer and a method for producing the same. For details, see the general formula, (However, R is H or CH ₃ ) A crosslinked polymer having an epoxysuccinic acid ester polymer unit having a refractive index of 1.50 to 1.57 and no melting point. Such polymers usually have the general formula: (However, R is H or _CH3 ) or a homopolymer of the epoxysuccinic unsaturated ester with another monomer copolymerizable with the ethylenically double bond portion of the epoxysuccinic unsaturated ester; or It is a copolymer. The present invention also provides a method for producing a crosslinked polymer by polymerizing the unsaturated epoxysuccinic ester or another monomer copolymerizable with the unsaturated epoxysuccinic ester in the presence of a radical polymerization initiator. Furthermore, the present invention also provides an optical glass containing the above-mentioned crosslinked polymer as a main component. Conventionally, various studies have been conducted and proposals have been made regarding synthetic resins to replace inorganic glass. For example, there have been proposals to polymerize monomers or monomer mixtures such as diethylene glycol bis(allyl carbonate) and methyl methacrylate as a substitute for inorganic glass. These polymers have advantages such as being lightweight and having good impact resistance compared to inorganic glass, but they have disadvantages such as poor abrasion resistance and a slightly low refractive index, so they are not necessarily suitable for use. It's not completely satisfying. As a result of many years of intensive research into polymers that compensate for the above-mentioned drawbacks, the present inventors have discovered that crosslinked polymers of unsaturated epoxysuccinic esters have extremely excellent properties, and have completed the present invention. . That is, the present invention provides at least the general formula, (However, R is H or _CH3 ) A crosslinked polymer having a refractive index of 1.50 to 1.57 and no melting point. Also, the general formula of the present invention Optical glass whose main component is an epoxysuccinic unsaturated ester represented by (R is H or _CH3 ) or a crosslinked polymer of the epoxysuccinic unsaturated ester and another monomer copolymerizable with the epoxysuccinic unsaturated ester. This is what we provide. The polymer of the present invention is a crosslinked polymer based on the above-mentioned unsaturated bonds. This point is also clear from the fact that the crosslinked polymer does not dissolve in various organic solvents or aqueous solvents. Further, the above-mentioned crosslinked polymer has a property of decomposing without melting when heated, and therefore does not have a melting point. Since the crosslinked polymer of the present invention does not dissolve in organic solvents or aqueous solvents, its molecular weight cannot be measured. Moreover, when the above-mentioned crosslinked polymer is heated, it does not melt but decomposes. The decomposition temperature varies depending on the type of raw material, especially the type of ester; for example, in the case of a crosslinked polymer of epoxysuccinic acid allyl ester, it is about 340°C,
In the case of a crosslinked polymer of epoxysuccinic acid metaallyl ester, the temperature is about 330°C. These decomposition temperatures can be confirmed by measuring with a thermobalance. Further, the crosslinked polymer of the present invention can be confirmed to be amorphous by X-ray diffraction. Furthermore, the crosslinked polymer of the present invention has a refractive index of 1.50 to 1.57. Generally, polymers such as methyl methacrylate and diethylene glycol bis(allyl carbonate) are used as optical glasses, but their refractive index is about 1.49, which is smaller than that of inorganic glasses, which is 1.52. On the other hand, the crosslinked polymer of the present invention has a refractive index approximately corresponding to that of inorganic glass. Further, the crosslinked polymer of the present invention has extremely good transparency (light transmittance), and generally has a transparency of 91%/2 mm or more. Usually, the transparency is most often in the range of 91-93%/2mm thickness. Furthermore, the crosslinked polymer of the present invention has an extremely excellent ultraviolet blocking effect, for example, 2
The ultraviolet transmittance of crosslinked polymers with a thickness of mm is 0% up to 280 mm and about 10% up to 300 mm. As is clear from the above description, the crosslinked polymer of the present invention has excellent dimensional stability and extremely good chemical resistance due to its crosslinked structure. Further, as will be described later, the crosslinked polymer of the present invention can be polymerized into various thicknesses. Therefore, the crosslinked polymer of the present invention can be used for almost the same purposes as inorganic glass, especially for microscopes,
Suitable for use in lenses or prisms of cameras, glasses, etc., dustproof glasses, windshield glasses, etc. The method for producing the unsaturated ester of epoxysuccinic acid used in the present invention is not particularly limited, but generally cis- or trans-epoxysuccinic acid is esterified with an unsaturated alcohol in the presence of a mineral acid or organic sulfonic acid catalyst. Obtained by conducting a reaction. These esterification reaction conditions may be selected from known esterification reaction conditions between an acid and an alcohol as they are or with some modification. R of the epoxysuccinic acid unsaturated ester represented by the above general formula is H or
CH ₃ is preferred, and if R is higher than ethyl, it is not preferred because it not only becomes expensive but also tends to have poor polymerizability. Therefore, epoxysuccinic acid diallyl ester, epoxysuccinic acid dimethallyl ester, etc. are most preferably used from the viewpoint of low cost production or good polymerizability. Other monomers that can be copolymerized with the epoxysuccinic unsaturated ester used in the present invention are not particularly limited, and generally, unsaturated compounds that are compatible with the epoxysuccinic unsaturated ester can be used. For the purpose of improving the polymerization rate, operability, etc. of epoxysuccinic acid unsaturated esters, or for the purpose of improving the physical properties of crosslinked polymers of epoxysuccinic acid unsaturated esters,
Generally, carboxylic acid monomers such as unsaturated carboxylic acids, unsaturated carboxylic esters, and unsaturated carboxylic esters are most commonly used. Typical examples of these are as follows. Unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic anhydride, itaconic acid, crotonic acid; methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, phenyl acrylate, methyl methacrylate, methacrylate Unsaturated dicarboxylic acid esters such as ethyl acid, n-butyl methacrylate, isobutyl methacrylate, glycidyl methacrylate, phenyl methacrylate, dimethyl maleate, diethyl maleate, dimethyl fumarate, diethyl fumarate; allyl propionate, α- Allyl chloropropionate, vinyl benzoate, allyl benzoate, vinyl acetate, allyl acetate, allyl chloroacetate, allyl dichloroacetate, methyl cinnamate, vinyl stearate, methallyl acetate, diallyl phthalate, isoallyl phthalate, stearyl phthalate , diallyl tartrate, diallyl malate, diallyl succinate, diallyl malonate, diallyl oxalate, diallyl glutarate,
Carboxylic acid unsaturated esters such as diallyl adipate, diallyl suberate, diallyl sebacate, ethyl vinyl oxalate, ethyl allyl oxalate, etc.; methyl allyl maleate, methyl allyl fumarate, diallyl maleate, diallyl fumarate,
Unsaturated esters of unsaturated carboxylic acids such as allyl acrylate, allyl methacrylate, allyl crotonate; ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene dimethacrylate, tetraethylene dimethacrylate, hydroquinone dimethacrylate, bisphenol A dimethacrylate, 2,2 screws (4
-Methacryloxyethoxyphenyl)propane,
Dialcohol unsaturated carboxylic acids such as neopentyl glycol dimethacrylate, propylene glycol dimethacrylate, butylene glycol dimethacrylate, diethylene glycol bis(allyl carbonate), ethylene glycol maleate, butylene glycol maleate, ethylene glycol fumarate, butylene glycol maleate etc. Other monomers copolymerizable with the unsaturated epoxysuccinic ester can be used in an amount of 10 to 900 parts by weight, but generally 20 to 800 parts by weight. It is most often used within a range. An unsaturated bond moiety is polymerized to the unsaturated epoxysuccinic ester to form the polymerized unit derived from the unsaturated epoxysuccinic ester, and at the same time, another monomer copolymerizable with the unsaturated epoxysuccinic ester. When used, a crosslinked polymer is obtained in which polymerized units derived from the other copolymerizable monomer are randomly bonded. The method for producing the crosslinked polymer of the present invention is obtained by polymerizing the unsaturated epoxysuccinic ester or another monomer copolymerizable with the unsaturated epoxysuccinic ester in the presence of a radical polymerization initiator. The above-mentioned radical polymerization initiator is not particularly limited, and known ones can be used. Typical radical polymerization initiators that are generally suitably used include, for example, benzoyl peroxide, diisopropyl peroxycarbonate, di-n-propyl peroxydicarbonate, di-sec-butyl peroxydicarbonate, di-2-ethylhexyl peroxydicarbonate, Carbonates, peroxides such as acetyl peroxide and diethyl peroxide, or azo compounds such as azobisisobutyronitrile are preferably used. The amount of the radical polymerization initiator to be used varies depending on the polymerization type, polymerization conditions, type of epoxysuccinic acid unsaturated ester, etc., and cannot be absolutely limited, but it is generally 0.1 to 10% (per epoxysuccinic acid unsaturated ester). It is most preferable to use a range of % by weight. The method for polymerizing the unsaturated epoxysuccinic ester in the present invention is not particularly limited, and any known polymerization method can be employed. An example of a typical polymerization method is a cast polymerization method. For example, an epoxysuccinic acid unsaturated ester containing a radical polymerization initiator or another monomer copolymerizable with the epoxysuccinic acid unsaturated ester is injected between a mold held by an elastomer gasket, and then cured in an air oven. It is best to take it out after washing. Among polymerization conditions, temperature in particular affects the properties of the crosslinked polymer obtained. Generally, it is preferable to carry out so-called two-stage polymerization in which polymerization is started slowly at a relatively low temperature and then cured at a high temperature when curing is completed. For example, it is preferable to start the polymerization at room temperature to about 50°C and terminate the polymerization at a high temperature of about 70 to 120°C. In particular, when the objective is to obtain a thick crosslinked polymer, it is preferable to lengthen the polymerization time at a low temperature. However, if the polymerization time is too long, especially at a high temperature, the crosslinked polymer may become colored, for example, yellow or yellowish brown, so it is not preferable to select a polymerization time longer than necessary. Generally, conditions are preferably selected so that the polymerization is completed in about 5 to 30 hours, preferably 10 to 25 hours. Since the polymerization time varies depending on various conditions, it is preferable to determine the optimum time according to these conditions in advance. Of course, during the polymerization, additives such as a mold release agent, ultraviolet absorber, various stabilizers, and anti-coloring agents can be selected and used as necessary. EXAMPLES In order to explain the present invention more specifically, the present invention will be described below with reference to Examples, but the present invention is not limited to these Examples. In addition, various physical properties of the crosslinked polymers obtained in the examples were measured by the following test methods. (1) Density Measured at a temperature of 20°C according to JIS Z8807. (2) Refractive index The refractive index at a temperature of 20°C was measured using an Abb refractometer. Monobromnaphthalene was used as a contact liquid. (3) Light transmittance Measured on a 2 mm thick test piece using a haze meter (Toyo Seiki Seisakusho). (4) Ultraviolet transmittance at 2 mm thickness using a spectrophotometer (Hitachi)
The test piece was measured at a wavelength of 210 to 360 mμ. (5) Hardness Using a Rockwell hardness tester, the value was determined using a 1/4-inch steel ball with a large load of 60 kg. (6) Impact resistance test Izoft impact resistance tester (Toyo Seiki Seisakusho)
It was measured according to the method of ASTM D256. (7) Abrasion test Using a Taber rotary abrasion tester (Toyo Seiki Seisakusho), a load of 750 kg was applied to 1000
The weight loss after rotation was measured and this value was expressed as a ratio to that of a commercially available methyl methacrylate polymer board. Furthermore, the abbreviations used in the examples are as follows. BAC: Diethylene glycol bis(allyl carbonate) MMA: Methyl methacrylate MA: Methyl acrylate VAc: Vinyl acetate AAc: Allyl acetate L-TA: L-Diallyl tartrate DAP: Diallyl phthalate EDMA: Ethylene dimethacrylate EGM: Ethylene glycol maleate MAN: Maleic anhydride DAM: Diallyl maleate Example 1 Purified diallyl epoxysuccinate ester
To 100 parts by weight, diisopropyl peroxycarbonate in the amount shown in Table 1 as a radical polymerization initiator and 300 ppm of di-n-butyl phosphate (containing 45% by weight of monobutyl phosphate) as a mold release agent were added and mixed well. This mixed solution was poured into a mold in which two glass plates were fixed with a gasket, and polymerized by casting. Polymerization was initially started at 30°C using an air oven.
The temperature was gradually raised until it reached 75°C in 16 hours. Furthermore, before the polymerization was completed, the temperature was raised to 90°C for post-curing. After the polymerization was completed, the mold was taken out of the air oven, allowed to cool, and then the polymer was peeled off from the glass of the mold. The ultraviolet transmittance of the crosslinked polymer of epoxysuccinic acid diallyl ester obtained in this way is 0% up to 280 mm, and about 10% at 300 mm, and the decomposition temperature is about 340°C as measured with a thermobalance. Ta. In addition, when comparing the monomer and the polymer of this example by infrared absorption spectrum, the C of 1646 cm ^-1 in the spectrum of the monomer shown in Figure 1.
The peak attributable to the =C bond almost disappears in the spectrum of the polymer shown in Figure 2, indicating that crosslinking polymerization has been substantially completely performed and the peak at 3030cm ^- attributable to the epoxy ring in Figure 2. The peak of ¹ and the peak of 1732 cm ^-1 caused by the ester group remain, indicating that the polymer of the present invention

It was confirmed that it has a group [Formula]. Furthermore, it was confirmed by X-ray diffraction that it was an amorphous substance. Furthermore, various physical properties of this crosslinked polymer were measured and summarized in Table 1.

[Table] Example 2 100 parts by weight of epoxysuccinic acid dimethallyl ester, 3 parts by weight of benzoyl peroxide as a radical polymerization initiator, and phosphoric acid di-n as a mold release agent.
-Butyl (contains 45% by weight of mono-n-butyl phosphate)
The mixed solution to which 300 ppm was added was injected into a mold and cast polymerization was performed. Polymerization was carried out using an air oven, starting at a temperature of 50°C and gradually increasing the temperature until it reached 90°C in 10 hours, and after reaching 90°C, heating was continued at that temperature for 3 hours. Example 1 after completion of polymerization
I performed the same operation. The decomposition temperature of the colorless and transparent crosslinked polymer of epoxysuccinic acid dimethallyl ester thus obtained is approximately 330°C, and the refractive index n _D
²⁵ is 1.51, light transmittance is 92%, hardness is 108, impact resistance test is 1.2Kg-cm/cm, abrasion resistance test is 8 times that of MMA board, specific gravity is 1.33, ultraviolet transmittance is 280mm
It was 0% up to 300mm, and about 10% at 300mm. Example 3 Except that epoxysuccinic acid diallyl ester used in Example 1 was replaced with epoxysuccinic acid diallyl ester, other copolymerizable monomers shown in Table 2, and a radical polymerization initiator (concentration: 1.6 parts by weight). was carried out in the same manner as in Example 1. The results were as shown in Table 2.

【table】

[Table] Example 4 In place of dimethylallyl epoxysuccinate used in Example 2, dimethallyl ester of epoxysuccinate and other copolymerizable monomers shown in Table 3 and diisopropyl peroxy as a radical polymerization initiator were used. The same procedure as in Example 1 was carried out except that 1.6 parts by weight of carbonate was used. The results were as shown in Table 3.

【table】 [Brief explanation of the drawing]

FIG. 1 is a chart of an infrared absorption spectrum of epoxysuccinic acid diallyl ester, and FIG. 2 is a chart of an infrared absorption spectrum of a polymer of epoxysuccinic acid diallyl ester. These infrared absorption spectra are based on JEOL Ltd.'s TIR-
100 and was measured on a silicon plate.

Claims (1)

[Claims] 1. As a constituent component, at least the general formula, (However, R is H or _CH3 ) A crosslinked polymer having a refractive index of 1.50 to 1.57 and having no melting point. 2 The polymer has the general formula, (However, R is H or _CH3 .) The crosslinked polymer according to claim 1, which is composed solely of an epoxysuccinate polymer unit represented by the formula: (R is H or CH3). 3 The polymer has the general formula, (However, R is H or _CH3 ) A patent claim consisting of an epoxy succinate polymer unit represented by the formula epoxy succinate polymer unit and a polymer unit derived from another monomer copolymerizable with the epoxy succinate polymer unit. The crosslinked polymer according to item 1. 4 Polymer is epoxy succinate polymerized unit
4. The crosslinked polymer according to claim 3, wherein the polymerized units derived from other copolymerizable monomers are comprised in the range of 10 to 900 parts by weight per 100 parts by weight. 5 At least a general formula as a constituent component, (However, R is H or _CH3 ) A polymer having an epoxysuccinic acid ester polymer unit, which has a refractive index of 1.50 to 1.57 and has no melting point as a main component. optical glass.