JPH011705A - new optical material - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an optical material, and more particularly to an optical material having excellent light transmittance, heat resistance, and moisture resistance.

(Prior art) Glass or polymeric substances are generally used as materials for optical recording media used in compact discs, video discs, computer discs, etc., but when mass-producing them, it is difficult to form them easily. A plastic material is preferable. In this case, the properties required of the plastic material are +1) good optical properties such as transparency, high light transmittance, and stable refractive index and low birefringence; (2) (3) It has chemical properties such as good adhesion with light reflective layers such as aluminum and silver, and strong protection against corrosion; (3) It has the strength necessary as a substrate and has sufficient heat deformation resistance. (4) having good moldability, etc.

Currently, polycarbonate, polymethyl methacrylate, etc. are used as plastic materials that can relatively meet these requirements, but polycarbonate has a high glass transition temperature (Tg) and has good heat resistance, but has poor moisture absorption. It is somewhat high, tends to cause birefringence, and has hydrolyzability due to its molecular structure. On the other hand, polymethyl methacrylate is transparent and has excellent optical properties such as a low birefringence, but it is highly hygroscopic and may cause corrosion of the light reflective layer and warping of the disk surface due to changes in size and shape. Occurs.

(Problems to be Solved by the Invention) As a result of intensive research to solve the above-mentioned drawbacks, the present inventors found that 8
It has been discovered that a cyclized product of a conjugated diene polymer or a hydrogenated product thereof having a cyclization rate of 0% or more has properties suitable for optical materials such as light transmittance, mechanical strength, heat resistance and moisture resistance, Based on this knowledge, we have completed the present invention.

(Means for Solving the Problems) According to the present invention, there is provided an optical material comprising a cyclized product of a conjugated diene polymer or a hydrogenated product thereof having a cyclization rate of 80% or more. be done.

The cyclized conjugated diene polymer used as the optical material of the present invention can be obtained by cyclizing a conjugated diene polymer as a raw material by a conventionally known method.

The conjugated diene polymer used as the raw material is a conjugated diene polymer or copolymer having a unit represented by the following formula in the polymer chain.

I R, -C-R.

In the formula, R1-R6 are hydrogen atoms, alkyl groups, or -
is a group.

Specific examples of the above units include 1,4-polybutadiene unit, 1.4-polyisoprene unit, 1.4-polypentadiene unit, 1,2-polybutadiene unit, ■, 2-polyisoprene unit, 3,4 - polyisoprene units, l.

4-poly(2-phenylbutadiene) ii'i position,
1.2-polypentadiene unit, etc. can be mentioned.

Examples of unsaturated monomers that can be copolymerized with these conjugated diene units include vinyl aromatic compounds such as styrene and α-methylstyrene; ethylenically unsaturated nitrile compounds such as acrylonitrile and methacrylonitrile;
Examples include unsaturated carboxylic acid esters such as methyl methacrylate and ethyl acrylate. The ratio of the conjugated diene units and the above-mentioned unsaturated monomer units in the conjugated diene polymer is 10,010 to 10/90, preferably 10,010 to 40/60.

The molecular weight of these conjugated diene polymers is usually from 50,000 to
2 million, preferably 100,000 to 1 million. When the molecular weight is small, the physical properties of the cyclized product obtained from it are poor, and when it is too large, the viscosity when dissolved in a solvent is high, making the cyclization reaction difficult and uneconomical. Here, the molecular weight is measured by high performance liquid chromatography using polystyrene as a reference and tetrahydrofuran as a carrier (MW).

The cyclized product of the conjugated diene polymer in the present invention can be obtained by dissolving the conjugated diene polymer in an inert solvent and then contacting it with a cyclization catalyst according to a conventionally known method.

The cyclization catalyst is not particularly limited, and for example, p-
Toluenesulfonic acid, methanesulfonic acid.

Examples include sulfonic acids such as trifluoromethanesulfonic acid, Friedel-Craft catalysts such as tin tetrachloride, ferric chloride, and boron trifluoride ether complexes.

The amount of the cyclization catalyst used is usually 100% of the conjugated diene polymer.
It is 0.1 to 15 parts per part.

The inert solvent may be any solvent as long as it does not react with the cyclization catalyst and the cations generated during the cyclization reaction, examples of which include:
Examples include hydrocarbons such as benzene, toluene, xylene, hexane and heptane, and halogenated hydrocarbons such as methylene chloride and chlorobenzene.

The concentration of the conjugated diene polymer in the cyclization reaction solution varies depending on the type of conjugated diene polymer used and the cyclization conditions, but is usually about 0.5 to 20 parts.

The pressure and temperature of the cyclization reaction are not particularly limited, but usually
It is carried out at a temperature of 0 to 120°C under normal pressure.

After reaching a predetermined cyclization rate in the cyclization reaction, the reaction is stopped with water or an aqueous acid solution such as hydrochloric acid or sulfuric acid, or an alkaline aqueous solution such as sodium carbonate or sodium hydroxide, and the reaction system is washed to remove the cyclization catalyst. By removing the residue, a solution of the cyclide is obtained. Further, by centrifuging this solution, trace amounts of water and the like contained in the solution may be removed.

Next, the cyclized product is recovered as a solid by a known method such as pouring this solution into a non-solvent of the conjugated diene polymer cyclized product.

In addition, to the cyclized conjugated diene copolymer of the present invention, a conventional anti-aging agent such as a phenol-based, sulfide-based, phosphite-based, or amine-based antiaging agent can be added to prevent gelation.

In the present invention, the cyclization rate of the conjugated diene copolymer cyclized product needs to be 80% or more. Cyclization rate is 8
If it is less than 0%, the heat resistance of the cyclized product obtained is low;
It cannot be put to practical use.

Here, the cyclization rate is, in the case of mypolyisoprene polymer,
According to the method of R.K. Agnihotri et al. described in Photographic Science and Engineering Vol. 16, No. 6, p. 443-448, and in the case of polybutadiene polymers, Journal of Polymer Science, Polymer Chemistry Edition, Vol. 17, p. 3027. It is measured by proton NMR spectrum according to the method of Tanaka et al. described in .

In addition, the molecular weight of the conjugated diene copolymer cyclized product is 10,000 to 100,000 to 100,000 as the value (MW) obtained by the above-mentioned molecular weight measuring method.
The number is preferably 50,000 to 800,000, preferably 50,000 to 800,000.

Next, the hydrogenated product of the cyclized conjugated diene polymer used as the optical material in the present invention can be obtained by hydrogenating the cyclized product of the conjugated diene polymer obtained as described above. The hydrogenation rate is theoretically 0-100%, assuming that all double bonds of the conjugated diene polymer cyclized product are saturated by hydrogenation as 100%.
There is a range of
Higher is preferable.

This hydrogenation reaction of the conjugated diene polymer cyclized product is usually carried out by a known method. As the hydrogenation catalyst, any catalyst that is commonly used in the hydrogenation of olefin compounds can be used, and is not particularly limited. For example, the following catalysts may be used. Examples of the heterogeneous catalyst include solid catalysts such as nickel/silica, in which nickel, palladium, platinum, or these metals are supported on a carrier such as carbon, silica, diatomaceous earth, alumina, titanium oxide, or the like.

Nickel/diatomaceous earth, palladium/carbon.

Palladium/silica, palladium/diatomaceous earth.

Examples include palladium/alumina. Homogeneous catalysts include those based on metals from Group 8 of the periodic table, such as nickel naphthenate/triethylaluminum, cobalt octate/n-butyllithium, nickel acetylacetonate/triethylaluminum, etc. , a Co compound and an organometallic compound of a metal of Groups 1 to 3 of the periodic table, or a Rh compound.

The hydrogenation reaction is carried out in a homogeneous or heterogeneous system depending on the type of catalyst, under a hydrogen pressure of 1 to 150 atmospheres, and at a temperature of 0 to 200°C, preferably 20 to 150°C.

In order to further improve the oxidative deterioration resistance, a stabilizer such as an ultraviolet absorber can be added to the hydrogenated product thus obtained, as long as the transparency does not deteriorate. It is also possible to mix and use other polymers that are compatible with this.

Examples of methods for molding the conjugated diene polymer cyclized product or its hydrogenated product of the present invention as optical materials include conventional molding methods such as casting, compression molding, injection molding, and spin cording.

The resulting molded products can be used as optical recording materials such as compact discs, video discs, and computer discs, as well as optical fibers and other materials that take advantage of their transparency, moisture resistance, and heat resistance.
fiber optic connector.

It can also be used in the fields of optical communications such as prisms and plastic lenses, lenses, protective films for photoresists, carrier films, and the like.

The present invention will be explained in more detail with reference to Examples below. Note that parts and percentages in Examples, Comparative Examples, and Reference Examples are based on weight unless otherwise specified.

■1 [Contents: In a M121 separable flask, add isoprene polymer (44.8% of cis-1,4-structural units, trans-1
, 4-structural unit 19.6%, 3.4-structural unit 35.6%
, Mw=235,000), and after purging with nitrogen, 390 g of dehydrated toluene was added under a nitrogen stream and stirred to form a uniform solution. The temperature of the reaction system was maintained at 20°C, and 0.1 g of trifluoromethanesulfone M was added and stirred for 60 minutes. Then, while stirring, add 5% aqueous solution of sodium carbonate.
j2 was added to stop the reaction. BHT (2,6-di-t-butylphenol)0 to prevent gelation of the product.
．． After adding 1 g of the product, the product was precipitated and recovered with a large excess of methanol, further washed with methanol, and then dried. The recovered cyclized product had a Mw of 180,000, a cyclization rate of 96%, and a Tg of 10.
It was 0°C.

Example 1L - 5% cyclohexane solution 4 of the polymer obtained in Reference Example 1
00g was charged into a No. 11 autoclave along with 2g of a catalyst consisting of 5% palladium on carbon. After purging the reactor with hydrogen, the temperature was raised to 120° C. with stirring. When the temperature of the reactor became constant, the hydrogen pressure was increased to 70 atm. After reacting for 8 hours while replenishing the hydrogen consumed by the reaction, the catalyst in the reaction product was filtered, precipitated in a large amount of acetone-isopropyl alcohol (1/1) mixed solvent, and filtered and dried. The hydrogenation rate of the obtained hydrogenated product was 95%.

``1 case'' Polyisoprene (98% cis-1,4-structural units.

The cyclization rate was 95% in the same manner as in Reference Example 1, except that trans-1,4-structural units (2%, MW = 700,000) were used.

A cyclized polyisoprene having Mw=250,000 was obtained.

1 by 1 example Polyisoprene (86% cis-1,4-structural units.

27! After the system was purged with nitrogen, 2.5 g of p-toluenesulfonic acid was added at 85° C. with stirring. After stirring for 5 hours, 25
The reaction was stopped by adding 0 g of water. After standing still, the oil layer was separated and washed five times with 250 g of water. This was poured into a large excess of 1% BIT methanol solution to recover the polymer, which was then dried under reduced pressure. The MW of this cyclized polyisoprene was 160,000, and the cyclization rate was 85%. A polymer with a hydrogenation rate of 95% was obtained according to the method of Reference Example 2.

Butadiene polymer (Mw=
210,000, 1,2- structural unit 96%, trans-1,4-
M
w=15,500, cyclization rate 97%.

A cyclized product with a Tg of 98°C was obtained.

1 Reason 1 M was prepared in the same manner as Reference Example 4 except that the reaction time was 180 minutes.
A cyclized polyisoprene with w=165,000 and a cyclization rate of 72% was obtained.

The polymers and polymethyl methacrylate obtained in Reference Examples 1 to 6 were made into a 2% toluene solution and cast onto a glass plate to obtain a thin film with a thickness of 10 μm.

Further, the cyclized polyisoprene obtained in Reference Example 2 was pressure-molded in a mold at 200° C. and 100 kg/cn to obtain a molded product having a thickness of las.

Table 1 shows the properties of these thin films and molded products.

(Effects of the Invention) As explained above, by using a conjugated diene polymer cyclized product having a cyclization rate of 80% or more or its hydrogenated product as a constituent material according to the present invention, light transmission is improved compared to the conventional technology. It is possible to obtain an optical material with excellent properties, heat resistance, and moisture resistance.

Patent applicant: Zeon Corporation

Claims (1)

[Claims] An optical material comprising a cyclized conjugated diene polymer having a cyclization rate of 80% or more or a hydrogenated product thereof.