JPH07118263A - Reactive oligomer - Google Patents

Abstract

PURPOSE:To obtain a reactive oligomer derived from 2,5-dimercaptomethyl-1,4- dithian, providing a polymer having a high refractive index and Abbe's number and excellent heat resistance, useful as a raw material for lens, prism, optical fiber, etc. CONSTITUTION:2,5-Dimercaptomethyl-1,4-dithian of formula I is reacted with methyl sulfoxide as an oxidizing agent under stirring at 80 deg.C for two hours. Then the reaction mixture is cooled, mixed with the same amount of water as that of methyl sulfoxide and extracted with chloroform. The extracted solution is washed with water, dried with magnesium sulfate and chloroform is distilled away under reduced pressure to give the reactive oligomer of formula II ((n) is 2-20 integer). This oligomer provides a polymer having high refractive index and Abbe's number and excellent heat resistance, suitable for optical materials such as optical lens, prism, filter, optical fiber, optical disc substrate, etc.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reactive oligomer and a reactive composition containing two or more reactive oligomers, which are useful as a raw material for an optical plastic material. The polymer (optical material) obtained by using the reactive oligomer of the present invention has a high refractive index and low dispersion, and is excellent in optical characteristics. Therefore, it is preferably used for camera lenses, spectacle lenses, contact lenses, optical lenses such as intraocular lenses, prisms, filters, optical fibers, and optical disk substrates.

[0002]

2. Description of the Related Art Plastic is lighter in weight, harder to break, and easier to dye than glass, and thus has been used in optical parts such as various lenses in recent years. As a practically used plastic material, poly (diethylene glycol bisallyl carbonate) (C
R-39), polymethylmethacrylate, and polycarbonate. Further, recently, a polyurethane obtained from pentaerythritol tetrakis (mercaptopropionate) and a diisocyanate compound, a polyurethane obtained from 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane and a diisocyanate compound, 2, Polymers obtained using 5-dimercaptomethyl-1,4-dithiane have been developed. These polymers are disclosed in JP-A-63-46213, JP-A-2-270859, and JP-A-3-236386.
Each of these publications discloses the same.

[0003]

In general, transparent glasses and polymers have a lower Abbe number (in other words, a higher dispersion) as the refractive index increases, and vice versa (Hans U. Simlock et al. Ange Hante Chemie, International Edition, Advanced Materials, 28
Vol., August / September issue, 1122 pages, 1989). Therefore,
Generally, it is considered extremely difficult to synthesize a polymer in which the refractive index and the Abbe number are simultaneously increased. On the other hand, research and development have been carried out to synthesize a polymer in which the refractive index and the Abbe's number are simultaneously increased.
Polymers described in JP-A-6213 and JP-A-2-270859 were obtained. However, the refractive index and Abbe number of these polymers are still not high enough to be applied to various optical designs.

Further, 2,5-dimercaptomethyl-1,4-dithiane (hereinafter sometimes abbreviated as DMMD) which is a polythiol compound described in JP-A-3-236386 has a refractive index of Abbe number at the same time,
And it is a material that is higher than the conventional one. The refractive index is 1.646 and the Abbe number is 35.2. Indeed, this compound has higher refractive index and Abbe number than the conventional polythiol compound. However, in particular,
In the field of spectacle lenses, it is desired to provide a material having a higher refractive index, and at that time, the Abbe number is required to be about the same as the conventional one.

Therefore, an object of the present invention is to provide a raw material compound of a polymer which has a higher refractive index and can maintain the Abbe number at least as high as that of conventional products, which is useful for optical materials and the like. is there.

[0006]

SUMMARY OF THE INVENTION The present invention is based on Formula 1 (wherein
n is an integer of 2 to 20).

[0007]

[Chemical 3]

Further, the present invention relates to a reactive composition containing two or more reactive oligomers represented by the formula 1 (wherein n is an integer of 2 to 20).

[0009]

[Chemical 4]

The present invention will be described in detail below. In the reactive oligomer of the present invention, the degree of polymerization n is 20 or less. This is because the oligomer tends to become cloudy as the degree of polymerization increases. The reactive oligomer having a degree of polymerization n of 20 or less is colorless and transparent. Further, the reactive composition of the present invention is a mixture in which two or more kinds of the above reactive oligomers are mixed.

The reactive oligomer of the present invention is essentially the above-mentioned 2,5-dimercaptomethyl-
It is an oxidation product obtained by oxidizing 1,4-dithiane (DMMD). However, in general, the oxidation product obtained by oxidizing DMMD contains reactive oligomers of different types having different degrees of polymerization n. Therefore, the reactive oligomer of the present invention is obtained by separating each oxidation product from the above oxidation products. A conventional method, for example, a method such as chromatography or molecular distillation, can be used to separate each oxidation product from the oxidation product. On the other hand, the reactive composition of the present invention contains reactive oligomers of different types having different polymerization degrees n, and may be the oxidation product itself. Alternatively, the reactive composition of the present invention is
A single or a plurality of reactive oligomers may be appropriately mixed with the oxidation product. The reactive composition of the present invention can also contain DMMD.

The reactive oligomer of the present invention can be produced by oxidizing DMMD as shown in the following scheme. When DMMD is oxidized, only the mercapto group of DMMD is oxidized, and a disulfide bond is generated between the molecules, which is sequentially condensed and oligomerized. However,
This oxidation produces disulfide bonds, but DMMD
Sulfur of 1,4-dithiane ring in the inside is oxidized under the condition that sulfone and sulfoxide are not generated (see the following formula).

[0013]

[Chemical 5]

Examples of the oxidizing agent used for the above oxidation include air (oxygen), hydrogen peroxide, halogens, hypohalous acid, methyl sulfoxide, manganese oxide (I
V) Iron (III) chloride, potassium hexacyanoferrate (III), nitric oxide, sulfuryl chloride, pyridine-N-
Oxide, N-nitroso-N-methyltoluene-p-
Examples include sulfonamide, flavin, and sulfur with butylamine as a catalyst. When air (oxygen) is used as the oxidant, the reaction solution is made alkaline or Cu (I
It is preferable to use I), Fe (III), or a cobalt complex as a catalyst because the oxidation reaction rate tends to increase. By using these oxidizing agents, it is possible to carry out an oxidation reaction in which only disulfide bonds are generated.

When DMMD is oxidized, the degree of polymerization increases as the reaction proceeds, and the oxidation product is not an oligomer having a single degree of polymerization but a mixture of oligomers having different degrees of polymerization. When the oxidation reaction proceeds to some extent, a polymer having a high degree of polymerization is precipitated, and the obtained oxidation product becomes cloudy. When the cloudy oxidation product is subjected to a polyaddition reaction with isocyanate, the obtained polyurethane also becomes cloudy. A cloudy polyurethane is not suitable as an optical material. Therefore, in the present invention, the value of the degree of polymerization n should not exceed 20 from the viewpoint of a colorless and transparent reactive oligomer suitable as an optical material. Regarding the oxidation reaction conditions for controlling the degree of polymerization n of the reactive oligomer to 20 or less, the reaction temperature and time may be appropriately adjusted according to the oxidizing agent used. For example, when oxidizing with air (oxygen) under Fe (III) catalyst, the reaction temperature is set to room temperature and the reaction time is set to 20 hours or less to obtain a reactive oligomer having a degree of polymerization n of 20 or less. In the case of oxidation with methyl sulfoxide, the reaction temperature is set to 80 ° C. and the reaction time is set to 8 hours or less to obtain a colorless and transparent reactive oligomer having a polymerization degree n of 20 or less.

In the reactive oligomer of the present invention, the higher the degree of polymerization n, the higher the refractive index and the lower the Abbe number.
Therefore, reactive oligomers having different degrees of polymerization n can be appropriately used depending on the refractive index and Abbe number required for the optical material obtained by using the reactive oligomer. Similarly, also in the reactive composition of the present invention, depending on the refractive index and Abbe number required for the optical material obtained by using the reactive composition, the kind of the reactive oligomer in the composition is appropriately selected. The (degree of polymerization) and the content rate can be selected. Further, as described above, in order to obtain a reactive oligomer having a desired refractive index and Abbe number, the oxidizing agent, the oxidation reaction temperature and the time may be appropriately adjusted.

The above-mentioned reactive oligomer and reactive composition of the present invention are useful as a monomer of a polymer (optical material). The degree of polymerization n of the reactive oligomer of the present invention may be 20 or less depending on the purpose of use of the reactive oligomer. For example, when used as a raw material of an optical material, n is 2 or less.
It is suitable that it is in the range of -10, preferably 2-5. The polymer obtained by using the reactive oligomer and the reactive composition of the present invention will be described below. The mercapto group at both ends of the reactive oligomer of the present invention can undergo an addition reaction with an iso (thio) cyanate group or a vinyl group. Therefore, the component A containing the reactive oligomer of the present invention, a compound having two or more vinyl groups in one molecule, a compound having two or more iso (thio) isocyanate groups in one molecule, and a compound in one molecule. Of the compounds having one or more vinyl groups and one or more iso (thio) cyanate groups,
Various polyaddition products can be obtained by subjecting the B component containing at least one kind to the polyaddition reaction.

The component A has a mercapto group and / or a hydroxy group in one molecule in addition to the reactive oligomer of the present invention in order to appropriately improve the physical properties of the polyaddition product,
And the total number of mercapto groups and hydroxy groups in one molecule is 2
The above compounds may be included. Specific examples of these compounds include trimethylolpropane, 1,2-ethanedithiol, 1,3-propanedithiol, tetrakis (mercaptomethyl) methane, pentaerythritol tetrakis (mercaptopropionate), pentaerythritol tetrakis (mercaptoacetate). , 2-mercaptoethanol, 2,3-dimercaptopropanol, 1,2-dihydroxy-3-mercaptopropane,
4-mercaptophenol, 1, n-benzenedithiol (n = 2,3,4), 1,3,5-benzenetrithiol, 1, n-bis (mercaptomethyl) benzene (n
= 2,3,4), 1,3,5-tris (mercaptomethyl) benzene, toluene-3,4-dithiol, bis (4-hydroxyphenyl) sulfide and the like.

On the other hand, the vinyl group-containing compound used as the component B is specifically divinylbenzene, ethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, and at least two or more in one molecule. And urethane-modified (meth) acrylates containing (meth) acryloxy groups, epoxy-modified (meth) acrylates, polyester-modified (meth) acrylates, and the like. The (meth) acrylate means both an acrylate and a methacrylate, and the (meth) acryloxy group means both an acryloxy group and a methacryloxy group.

The isothiocyanate group-containing compound used as the component B is specifically xylylene diiso (thio) cyanate, 3,3'-dichlorodiphenyl-4,4'-diiso (thio) cyanate, 4,4 '. -Diphenylmethane diiso (thio) cyanate, isophorone diiso (thio) cyanate, 2,2 ', 5,5'-tetrachlorodiphenyl 4,4'-diiso (thio) cyanate, tolylene diiso (thio) cyanate, etc. To be

Specific examples of the vinyl group- and iso (thio) cyanate group-containing compound used as the component B include 2
-(Meth) acryloxyethyliso (thio) cyanate, (meth) acryloyliso (thio) cyanate and the like can be mentioned.

The components A and B are (vinyl group + iso (thio) cyanate group) / (mercapto group + hydroxy group)
It is suitable to uniformly mix them so that the value of is within the range of 0.5 to 3.0 to obtain a polymerization raw material mixture. However,
When the component B contains a vinyl group, it is preferable that all the polymerization functional groups of the component A are mercapto groups.
A catalyst can also be used for this polyaddition reaction.
Therefore, the catalyst can be appropriately added to the polymerization raw material mixture. Examples of the catalyst include organic peroxides, azo compounds, and basic compounds in the reaction of a mercapto group and a vinyl group. Further, in the reaction of a mercapto group or a hydroxy group with an isothiocyanate group, an organic tin compound or an amine compound can be given as an example of the catalyst. Further, in order to improve the light resistance of the obtained polymer, an ultraviolet absorber, an antioxidant, a coloring preventing agent and the like may be appropriately added to the polymerization raw material mixture.

A polymer is obtained by pouring the mixture of the polymerization raw materials containing the components A, B, additives and catalysts obtained above into a container of an appropriate shape and heating. The container may be subjected to a mold release treatment so that the polymer can be easily taken out from the container, or a mold release agent may be mixed in the polymerization raw material mixture in advance. The polymerization temperature is preferably in the range of -20 to 150 ° C, and the polymerization time is suitably in the range of 0.5 to 72 hours.
The polymer thus obtained is particularly preferably used for, for example, plastic lenses.

[0024]

EXAMPLES The present invention will be further described below with reference to examples.
The various physical properties in the examples were measured by the following methods. [Measurement of visible light transmittance (T%)] Using a spectrometer UV-330 manufactured by Hitachi, Ltd., the transmittance of a sample having a thickness of 1 mm and having both surfaces polished was measured in the range of 450 to 900 mm. [Measurement of Refractive Index (n _D ) and Abbe's Number (ν _D )] It was measured at 20 ° C. using an Abbe refractometer 3T manufactured by Atago. Diiodomethane was used as the contact liquid between the sample and the prism. [Heat resistance] The temperature was raised by 10 ° C./min while applying a load of 10 gf with a 0.5 mmφ pin using a TMA apparatus manufactured by Rigaku Corporation, and the thermal deformation start temperature was read from the obtained chart for evaluation.

Example 1 (Synthesis 1 of Reactive Oligomer 1 (when oxidizing with methyl sulfoxide)) 31.17 g (0.147 mol) of DMMD was added with 45.86 g (0.587 mol) of methyl sulfoxide. In addition, it stirred at 80 degreeC for 2 hours.
After cooling the reaction mixture, the same amount of water as methyl sulfoxide was added, and the mixture was extracted with chloroform. Wash the extract with water,
It was dried over magnesium sulfate and chloroform was removed under reduced pressure to obtain a mixture of the reactive oligomer of the present invention (yield about 90%). n _D / ν _D = 1.680 / 34.3; ¹ H-NMR (C
DC1 ₃ ) δ 1.59-1.65 (m, 100H), δ
2.80-3.20 (m, 10.2H); IR (liquid film method) 2901, 2543, 1406, 1311, 125
9, 1228, 1210, 1181, 907, 694c
m ^-1 ; Raman 500, 540, 630, 720, 79
From the ratio of the areas of the charts obtained by the 0,1400,2550,2900 cm ^-1 GPC analysis, the obtained mixture of reactive oligomers was 6.54% of DMM.
D, 29.9% dimer, 26.4% trimer, 17.
It contained 7% of tetramer and 19.5% of an oligomer mixture having a degree of polymerization of 5 or more.

Example 2 (Synthesis of Reactive Oligomer 2 (Fe (III) Catalyzed,
When oxidizing with air) 97.54 g (0.46 mol)
460 ml of methanol was added to DMDM of
A solution of 124.11 g (0.46 mol) of ferric chloride hexahydrate in methanol (320 ml) was quickly added,
Stir at room temperature. After stirring for 4 hours, the precipitate was taken out by decantation, dissolved in chloroform, the solution was washed with water and dried over magnesium sulfate. Chloroform was removed under reduced pressure to obtain a mixture of reactive oligomers of the present invention (yield about 90%). n _D / ν _D = 1.665 / 35.0 From the area ratio of the chart obtained by GPC analysis, the reactive oligomer mixture obtained was 3.64% DMM.
D, 58.5% dimer, 26.5% trimer, 8.5
It contained 2% of tetramer and 2.84% of an oligomer mixture having a degree of polymerization of 5 or higher.

Comparative Example 1 The refractive index of DMMD described in JP-A-3-236386 was 1.646, and the Abbe number was 35.2.

Application Example 1 (Synthesis of Polymer) Mixture of reactive oligomers obtained in Example 1 (NMR
3.74 g (10)
^-2 mol), 1,3-bis (isocyanatomethyl) cyclohexane 1.94 g (10 ^-2 mol) and dibutyltin dichloride 3.0 mg (10 ^-5 mol) were uniformly mixed. Then, this mixture was degassed in vacuum and then poured into a glass container, which was heated at 50 ° C for 10 hours and then at 60 ° C for 5 hours.
A polymer was obtained by heating at 120 ° C. for an hour.
The obtained polymer is rigid and has a visible light transmittance (45
0-900 nm) is 87-92%, refractive index (n _D ) is 1.645, Abbe number (ν _D ) is 37.0, and heat resistance is 1
It was 14 ° C. ¹ H-NMR (in DMSO-d ₆ ) δ 0.4-1.8
(M, 1.00H), δ2.75-3.40 (m, 2.
33H); IR (KBr) 3307, 2914, 1653, 150
0,1404,1191 cm ^-1 ; Weight average molecular weight (polystyrene conversion) 15400

Application Examples 2 to 10 Using the raw materials shown in Table 1, the same operation as in Application Example 1 was carried out to obtain a polymer. Table 1 shows the physical properties of these polymers. From Table 1, the polymers of Application Examples 2 to 10 are colorless and transparent because of their high visible light transmittance, and have a refractive index (n _D ) of 1.
630 to 1.677, Abbe number (ν _D ) is 34.2 to 4
The heat resistance was 1.0 to 109 to 129 ° C.

Application Comparative Example 1 Pentaerythritol tetrakis (mercaptopropionate) 4.88 g (10 ^-2 mol), m-xylylene diisocyanate 3.76 g (2 x 10 ^-2 ) and dibutyltin dichloride 6.1 mg (2) The mixture of × 10 ⁻⁵ ) was stirred uniformly. The obtained mixture was vacuum degassed, poured into a glass container, and heated at 50 ° C. for 10 hours, 60 ° C. for 5 hours, and 120 ° C. for 3 hours to obtain a polymer. Table 1 shows the physical properties of the obtained polymer. From Table 1, the polymer obtained in this application comparative example was colorless and transparent, but had a refractive index (n _D ) of 1.59 and a heat resistance of 86 ° C. It was inferior to any of the obtained polymers.

Application Comparative Examples 2 and 3 Using the raw material compositions shown in Table 1, the same operation as in Application Comparative Example 1 was carried out to obtain a polymer. Table 1 shows the physical properties of these polymers. From Table 1, the polymer of Application Comparative Example 2 has a relatively high refractive index (n _D ) of 1.670 but is yellow,
The Abbe number (ν _D ) was 28 and the heat resistance was 94 ° C., and the latter three properties were inferior to any of the polymers obtained in the above application examples. The polymer obtained in Application Comparative Example 3 was colorless and transparent, had an Abbe number (ν _D ) of 52 and a heat resistance of 101.
Although it was relatively high (° C.), the refractive index (n _D ) was 1.530, which was lower than any of the polymers obtained in the above application examples.

[0032]

[Table 1]

RO-1: Reactive oligomer mixture obtained in Example 1 RO-2: Reactive oligomer mixture obtained in Example 2 HXDI: 1,3-bis (isocyanate) Methyl) cyclohexane XDI: m-xylylene diisocyanate DIH: 1,6-diisocyanatohexane 4-MP: 4-mercaptophenol PETMA: pentaerythritol tetrakis (mercaptoacetate) IPDI: isophorone diisocyanate TDI: toluene diisocyanate EDT: ethanedithiol EDMA: Ethylene glycol dimethacrylate MEI: 2-methacryloxyisocyanate DBTDC: Dibutyltin dichloride DBTDL: Dibutyltin dilaurate ADVN: Azobisdimethylvaleronitri

In FIG. 1, the relationship between the refractive index and the Abbe number of the polymer obtained in the above application example is shown by a black circle (●). For comparison, the relationship between the refractive index and Abbe number of the lens polymer described in JP-A-63-46213 is shown by a square (□), and the refractive index of the lens polymer described in JP-A-2-270859. And the Abbe number are indicated by white circles (○).
The relationship between the refractive index and the Abbe number of the lens polymer described in Japanese Patent No. 36386 is shown by a triangle (Δ). As is clear from FIG. 1, the polymer (optical material) using the reactive oligomer of the present invention has higher refractive index and lower dispersion (higher Abbe number) than conventional polymers.

[0035]

The reactive oligomer of the present invention has a higher refractive index than conventional thiol compounds and has the same Abbe number. Therefore, the polymer (optical material) using the reactive oligomer of the present invention as a raw material has a high refractive index and an Abbe number and is excellent in heat resistance. Therefore, camera lenses, eyeglass lenses, contact lenses, optical lenses such as intraocular lenses, prisms, filters, optical fibers,
It is preferably used for optical products such as optical disc substrates.

[Brief description of drawings]

FIG. 1 shows the relationship between the refractive index and Abbe number of various polymers.

Claims (2)

[Claims] 1. A reactive oligomer represented by Formula 1 (wherein n is an integer of 2 to 20). [Chemical 1] 2. A reactive composition comprising two or more reactive oligomers represented by formula 1 (wherein n is an integer from 2 to 20). [Chemical 2]