JPH03118523A - Nonlinear high-polymer 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 a nonlinear polymer material that can be used as an element material for optical signal processing devices and the like.

[Conventional technology]

In recent years, with the development of high-energy-density laser light sources, research on nonlinear optical phenomena, which is the interaction between materials and strong electromagnetic waves, has been actively conducted.

Nonlinear optical phenomena are generally phenomena in which changes in the permittivity of a material due to the incidence of electromagnetic waves on the material are no longer proportional to the electric field amplitude, and are known as higher-order radio frequency generation, mixed wave generation, parametric effects, etc. There is. This phenomenon is used in devices such as laser media, optical bistable devices, optical switches, and optical memories.

Various materials such as inorganic or organic compounds and semiconductors are used as materials for optical elements exhibiting the above phenomenon. Among these, organic materials include L i Nb O3 and K H! P.O.
It has the advantage of having a larger nonlinear optical constant than inorganic materials such as ferroelectric crystals such as Ga 4, and faster response speed than semiconductor materials such as Ga 8.

For this reason, including paratoluenesulfonate derivatives of polydiacetylene (abbreviated as PTS-PDΔ),
Research is actively progressing on π-electron conjugated polymer materials such as polyacetylene, and organic low-molecular compounds with asymmetrically substituted aminonitrostilbene donors and acceptors.

Devices include coupler-type optical switches in which the outer periphery of the cladding of a silica-based optical fiber coupler is filled with a nonlinear material, optical switches in which an organic nonlinear material is used as the cladding material of a waveguide or plastic clad fiber (PCF), or wavelength Devices such as conversion elements are attracting attention in terms of both productivity and characteristics.

[Problem to be solved by the invention]

According to the operating principle of these devices such as optical switches,
The refractive index of the applied organic nonlinear material must be the same as or lower than that of the core material and cladding material. In particular, when the core material and cladding material are silica glass, the refractive index of the glass is approximately 1. Must be lower than 45.

On the other hand, ordinary organic nonlinear materials (low-molecular compounds) are
Since it contains a conjugated moiety such as a phenyl group in its molecular skeleton, its refractive index is considerably higher than that of glass, making it unsuitable for the purpose of the present invention.

The simplest solution to this problem is to adjust the refractive index by dispersing the organic nonlinear material in a polymer compound whose refractive index is lower than that of glass. As such low refractive index polymer compounds, silicone resins with main skeletons of polydimethylsiloxane and polyorganosilsesquioxane are considered to be promising in terms of cost, transparency, stability, etc. It is being

However, conventionally, in systems using such silicone resin as a host material (solvent or dispersion medium), it is not possible to mix a large amount of organic nonlinear material due to poor compatibility between organic nonlinear material and silicone resin. Therefore, there was a problem that high nonlinear characteristics could not be obtained.

In view of the above-mentioned current situation, the object of the present invention is to provide a nonlinear polymeric material of a type in which an organic nonlinear material having a refractive index higher than that of glass is dispersed and compatible with a polymeric compound having a refractive index lower than that of glass. The object of the present invention is to provide a novel nonlinear polymer material that can incorporate a large amount of organic nonlinear material and exhibit high nonlinear characteristics.

[Means to solve the problem]

As a result of extensive studies and research to solve the above problems, the present inventors have found that if a silicone resin containing a carboxyl group in the side chain or terminal part is used as a solvent or dispersion medium, the amount of organic nonlinear material added can be reduced. The inventors have discovered that it is possible to increase the refractive index of the cladding, thereby exhibiting a large nonlinear optical effect, and to make the refractive index almost the same as that of the cladding, leading to the present invention.

That is, the present invention is a nonlinear polymeric material made by dispersing or dissolving a compound having a nonlinear optical effect in a silicone resin that has optical transparency and contains a carboxyl group in a side chain or terminal portion.

Furthermore, the present invention provides a nonlinear polymer in which a compound having a nonlinear optical effect is dispersed or dissolved in a silicone resin that is transparent and has a carboxyl group in a side chain or a terminal portion, and the silicone resin is further crosslinked. Provide materials.

The crosslinked nonlinear polymeric material of the present invention has an improved nonlinear optical effect, a decrease in the nonlinear effect over time, and a refractive index that is almost unchanged from that before crosslinking (uncured).

[Effect]

The present inventors investigated the introduction of polar functional groups into silicone resin as a means of lowering the refractive index of the entire material without lowering the compatibility between the organic nonlinear material and the resin. As a result, they found that by incorporating carboxyl groups into the resin, the solubility of nonlinear materials can be dramatically increased without causing a large change in the refractive index.

In the present invention, examples of the carboxyl group-containing silicone resin include those represented by repeating units represented by the following general formulas (11 and (2)).

General formula (1) [However, in formula (11, R+ and I% are each -""(Cl-
1! +V- or →CH* θic--- 0
→CH! (A, m.

n is an integer from 0 to 10), Rs, R
6 each represents an alkyl group or an aryl group, and a is 1
General formula (2) representing an integer from 0 to 10,000 [However, R'4+R; in formula (2) each represents an alkyl group or an aryl group, and R7 is →CHt 5 or →CH*tO→CH curve - (L m and n each represent an integer of 0 to 1O, and b and C each do not represent an integer of 10 to 1ooo]) From the repeating unit represented by the above general formula (1) or (2) The silicone resin according to the present invention has a side chain Rs,
R;, R4, R'4. By selecting an alkyl group such as a methyl group or an ethyl group for Rs and g, a refractive index of about 1.40 can be obtained, and by selecting an aryl group such as a phenyl group for the side chain, a refractive index of about 1.52 can be obtained. It is possible to obtain a refractive index of approximately Furthermore, by changing the ratio of alkyl groups to aryl groups, the refractive index can be set within the range of 1.40 to 1.52.

The amount of carboxyl group introduced into the resin is usually 0.3 to 1.
It is preferably in the range of 0% by weight.

If the amount introduced is less than 0.3% by weight, no improvement in compatibility can be expected, and if it exceeds 10% by weight, not only will the effect of increasing compatibility be no longer expected, but also the refractive index will decrease due to the addition of carboxyl groups. This is not desirable because the increase cannot be ignored.

As described above, the silicone resin represented by the repeating unit of general formula +11 or (2) of the present invention has a refractive index of 1.4.
Since it can be arbitrarily adjusted within the range of 0 to 52 mm, if a compound having a nonlinear optical effect is dispersed and compatible with this as a solvent or dispersion medium, the refractive index can be adjusted to the desired refractive index, and it is also more nonlinear than conventional ones of this type. A nonlinear optical material to which a larger amount of a compound having an optical effect can be added can be obtained. A specific means for obtaining the nonlinear polymer material of the present invention is to add the organic nonlinear low molecular compound to the silicone resin according to the present invention, and disperse or dissolve the organic nonlinear low molecular compound by stirring or the like.

It is desirable that the refractive index of the resin composition in which the nonlinear optical material is dissolved or dispersed is slightly smaller than the refractive index of the core and cladding of the nonlinear fiber, and when the core and cladding are quartz, the refractive index of the resin composition is A suitable value is n=1.40 to 1.45.

Furthermore, some or all of the carboxyl groups of the silicone resin represented by the above general formula (2), or the general formula (
By modifying the carboxyl group at one end or both ends of the silicone resin shown in 1) with a reactive vinyl mercapto group, etc., and adding a platinum catalyst, hydrogen polysiloxane, photoinitiator, etc., ultraviolet rays or heat resistant It is also possible to crosslink with energy. This crosslinking is performed after dispersing or dissolving a compound having a nonlinear optical effect in the silicone resin. With crosslinking, the nonlinear optical effect is further increased and decreases less over time.

The silicone resin containing a carboxyl group in the side chain or terminal part according to the present invention is a commercially available product, such as Tomu Silicone BYI6-750 (trade name, terminal) 5F8
418 (trade name, side chain), Shin-Etsu Chemical X-22-162
C (terminal) Toshiba Silicone X22-3401E (side chain), Toshiba Silicone XF42-A0383 (side chain), Toshiba Silicone XF42
-508 (terminal) etc. can also be used.

Examples of the organic compound having a nonlinear optical effect according to the present invention include the following.

The symbols in parentheses are abbreviations. For example, 2-methyl-4 nitroaniline (MNA), meta-nitroaniline (m
NA), rose-nitroaniline (pNΔ), 4-diethylamino-4'-nitrostilbene (DEANS)
, 4-dimethylamino-4'nitrostilbene (DAN
S), 2-C ethyl (4-C(4-nitrophenyl)
Azo]phenyl]amino]ethanol (redl), 4
-dipropylamino-4'-nitrostilbene, 4-dibentylamino-4'-nitrostilbene, 4-dihexylamino-4'-nitrostilbene, 2-[methyl(4-C(4-nitrophenyl)azo) [phenyl]amino]ethanol, 2-(4-((4-nitrophenyl)azo]phenyl]amino)ethanol, 2-[propyl[4-[(4-nitrophenyl)azo]phenyl]amine]ethanol, 2 -[ButylC4-CC4-nitrophenyl]azo]phenyl]amino]ethanol, 2-
[pentyl[4-((4-nitrophenyl)aso]phenyl]amino]ethanol, 2-[hexyl (4-1:
(4-nitrophenyl)aso]phenyl]amino]ethanol, 2-[ethyl(4-[(4nitrophenyl)azo]phenyl]amine]methanol, 2-[ethyl[4
, -[(4-nitrophenyl)azo]phenyl]amino]propatol, 2-[ethylC4-CC4-nitrophenyl)azo]phenyl]amino]butanol, 2-[
Ethyl (4-[(4-nitrophenyl)aso]phenyl]amino]pentanol, 2-[ethyl[4[(4-nitrophenyl)azo]phenyl]amino]hexanol, 3-methyl 4-nitropyridine-1 -Oxide, 3
-Methyl-(2,4-dinitrophenyl)-aminopropanate, N-4 nitrophenylpropanate, 2-C
(4[(4-nitrophenyl)azo]phenyl)amine]methanol, 2-[(4-[(4-nitrophenyl)azo]phenyl)aminocopropatol, 2-((
4-1: (4-nitrophenyl)azo]phenyl)aminocobutanol, 2-[:(4-[(4-nitrophenyl)azo]phenyl)aminocopentanol, 2-
[(4-C(4-nitrophenyl)azo]phenyl)aminocohexanol, 2-[methyl[4-[(4-nitrophenyl)azo]phenyl]amino]methanol, 2
-[MethylC4-C(4-nitrophenyl)aso]phenyl]amino]propatur, 2-[methyl[4[(4
-nitrophenyl)azo]phenyl]amino]butanol, 2-[methyl[4-[(4-nitrophenyl)azo]phenyl]amino]pentanol, 2-[methyl[4
-[(4-nitrophenyl)azo]puenyl]amino]
Hexanol, 2-[propylC4-CC4-nitrophenyl]azo]phenyl]amino]methanol, 2-[
Propyl[4-((4-nitrophenyl)azo]phenyl]amino]propatur, 2-[propyl(4-CC
4-nitrophenyl)aso]phenyl]amino]butanol, 2-[propyl[4-[(4-nitrophenyl)
Azo]phenyl]amino]penknol, 2-[propylC4-CC4-nitrophenyl]azo]phenyl]amino]hexanol, 2-[butyl[1-[(4-nitrophenyl)azo]phenyl]amino]methanol ,2
[Butyl[4-[(4-nitrophenyl)azo]phenyl]amino]propertool, 2-[butyl[4-((4
-nitrophenyl)aso]phenyl]amino]butanol, 2-[butyl(4-[(4nitrophenyl)azo])
phenyl]amine]pentanol, 2-[butyl(4-
[(4-nitrophenyl)azo]phenyl]amino]hexanol, 2-[pentyl[4-I(4-nitrophenyl)azo]phenyl]amino]methanol, 2-[pentyl[4-[(4-nitrophenyl) ) azo]phenyl]amino]propatur, 2-[pentyl C4-CC4
-nitrophenyl)azo]phenyl]amino]butanol, 2-[pentyl[4[(4-nitrophenyl)azo]phenyl]amino]pentanol, 2-[pentyl[
4-[,(4-nitrophenyl)azo]phenyl]amino]hexanol, 2-[hexyl[4-[(4-nitrophenyl)azo]phenyl]amino]methanol, 2-
[Hexyl l: 4-((4-nitrophenyl)azo]phenyl]amino]propertool, 2-[hexyl(4-
C(4-nitrophenyl)azo]phenyl]amino]butanol, 2-[hexyl[4-((4-nitrophenyl)azo]phenyl]amino]pentanol, 2-[hexyl[4-((4-nitrophenyl)azo]phenyl]amino]pentanol, phenyl)aso]phenyl]amino]hexanol, etc. The method for preparing the nonlinear polymeric material of the present invention and other details will be described in the following Examples.
I will explain.

〔Example〕

Examples 1 to 9, Comparative Examples 1 to 4 Various organic nonlinear materials shown in Table 1 below were dissolved in a silicone resin containing 0 to 9.5% by weight of carboxyl groups, and in a dissolved state (uncured). The saturated solubility at room temperature was investigated. The results are also shown in Table 1.

All of the materials obtained in Examples 1 to 9 above were optically transparent, and when their refractive indexes were measured, they were all between 1.41 and 1.44 at a wavelength of 1.30 microns, indicating that they were We were able to obtain a refractive index low enough to be used for.

On the other hand, in the materials obtained in Comparative Examples 1 to 4, only about 1 to 2% of the nonlinear optical material was dissolved, so that sufficient nonlinear characteristics could not be obtained.

Furthermore, when these materials were applied to a coupler type optical switch shown in FIG. 1 as an example of a device, it showed excellent response characteristics. In FIG. 1, l represents a fiber, 2 represents a coupler storage case, 3 represents an optical coupling section, 4 represents a nonlinear polymer material of the present invention, 5 represents an electrode, and 6 represents a conducting wire. FIG. 2 is a sectional view taken along the line AA in FIG. 1.

Table 1 Example IO The material of Example 9 in which the resin side chain was modified with a vinyl group or mercapto group was crosslinked to obtain a crosslinked nonlinear polymer material, and the coupler type optical switch shown in Fig. 1 was fabricated. , this one also showed excellent response characteristics.

Although organic nonlinear materials were used in the above embodiments, inorganic compounds other than organic compounds and semiconductors may be used as the compound having the nonlinear optical effect of the present invention.

〔Effect of the invention〕

As explained above, the present invention uses a carboxyl group-containing silicone resin as a light-transmitting polymer compound to improve compatibility with a compound having a nonlinear optical effect and to have a low refractive index (approximately the same as that of a cladding). Equivalent) materials can be realized. Furthermore, the crosslinked nonlinear polymeric material of the present invention is an excellent material that not only improves the nonlinear effect but also provides stable effects over time.

Furthermore, it has been found that the nonlinear polymeric material of the present invention exhibits excellent electro-optical properties and is fully applicable to a coupler-type optical switch, for example, which was attempted to be made into a device.

[Brief explanation of drawings]

FIG. 1 is a plan view of a coupler type nonlinear switch using the nonlinear polymer material of the present invention, and FIG.
It is an A sectional view. In the figure, 1 is a fiber, 2 is a coupler storage case, 3 is an optical coupling part, 4 is a nonlinear polymer material of the present invention, 5 is an electrode, 6
represents a conductor.

Claims (2)

[Claims] (1) A nonlinear polymeric material made by dispersing or dissolving a compound having a nonlinear optical effect in a silicone resin that is optically transparent and contains a carboxyl group in a side chain or end. (2) A nonlinear polymeric material obtained by dispersing or dissolving a compound having a nonlinear optical effect in a silicone resin that is optically transparent and containing a carboxyl group in a side chain or end, and further crosslinking the silicone resin.