DE3613993A1 - ANISOTROPE POLYMER MATERIALS - Google Patents

Abstract

Anisotropic polymer materials are obtained by polymerisation of mixtures of polymerisable compounds and of compounds producing non aqueous, lyotropic phases.

Description

The invention relates to anisotropic polymer materials as well a process for their manufacture.

Anistropic polymer materials are suitable, for example as optical media in electronics.

It is a series of processes for making anisotropic Polymer known. For example, through polymerization thermotropic liquid crystals, as in Barrall II, Johnson, J. Macromol. Sci., Rev. Macrom. Chem. 17 (1979) 137, polymers with anisotropic optical, maintain electrical and magnetic properties.

Orientation effects at liquid-liquid interfaces can such as B. Millich, Carracher, Jr., ed .: Interfacial Synthesis, Marcel Dekker, New York-Basel, 1977, be used for the production of anisotropic polymers.

Aqueous micellars (e.g. Sudhölter et al., Recueil 99 (1980) 73) and vesicular (see Tendler: Membrane Mimetic Chemistry, John Wiley and Sons, New York, 1982) allow arrangements also the synthesis of anisotropic polymers.

The previously known methods have a number of disadvantages on. The polymerization of thermotropic liquid crystalline Substances often require the use of expensive ones difficult to access compounds, the monomer material  largely consist of anisotropic building blocks got to. The anistropic order of the monomers is also common lost in the polymerization.

Interface polymerizations and the use of micellar and vesicular systems require the use of aqueous or water-like, polar solvent, whereby a Variety of common monomers and oligomers from use is excluded. Solvents will be present often stubbornly held on by the cured polymers; Attempts to remove them are capable of anisotropic Destroy order.

There is therefore a need for a method for Production of anisotropic polymer materials, the described Disadvantages not or only to a lesser extent having.

This object is achieved by the method according to the invention for the production of anisotropic polymer materials.

The invention therefore relates to a method for the production anisotropic polymer materials by conventional polymerization polymerizable compounds, characterized in that the polymerization in the presence at least a non-ionic, lyotropic phase-producing compound is carried out.

Suitable polymerizable compounds are both a capable of free radical initiation polymerization mono- or polyfunctionally ethylenically unsaturated monomers, Oligomers or prepolymers or their mixtures as also accessible to polycondensation or polyaddition or polyfunctional monomers, oligomers or prepolymers or their mixtures. The prior art offers this a wide range of suitable connections.  

Suitable as ethylenically unsaturated compounds for example ethylene, propylene, butene, isobutylene, Butadiene, isoprene, vinyl chloride, vinylidene chloride, acrylonitrile, Methacrylonitrile, acrylamide, methacrylamide, methyl, Ethyl, n- or tert. Butyl, cyclohexyl, 2-ethylhexyl, Benzyl, phenoxyethyl, hydroxyethyl, hydroxypropyl, lower alkoxyethyl, tetrahydrofurfurylacrylate or methacrylate, vinyl acetate, propionate, acrylate, succinate, N-vinylpyrrolidone, N-vinylcarbazole, styrene, divinylbenzene, substituted styrenes, as well as the mixtures of such unsaturated compounds. Also polyunsaturated Compounds such as ethylene diacrylate, 1,6-hexanediol diacrylate, propoxylated bisphenol A diacrylate and dimethacrylate can in the inventive method be used. Ethylenically unsaturated compounds can be radical, ionic or by means of Polymerize metal complexes.

The radicals required to initiate the polymerization can arise in different ways, e.g. B. by Irradiation of the monomers with UV light, X-rays or radioactive sources.

Sunlight or artificial can be used as radiation sources Spotlights can be used. Z are advantageous. B. high pressure mercury vapor, Medium pressure or low pressure lamps, Xenon and tungsten lamps; Laser light sources and Electron tubes can also be used.

There is also a chain start of the polymerization reaction possible by the decomposition of material initiators Heating or radiation. Suitable initiators are for example dibenzoyl peroxide, azo-bis-isobutyronitrile, Potassium persulfate, dibenzoyl peroxide, cumene hydroperoxide or Di-tert-butyl peroxide.  

To dissolve an ionically initiated polymerization For example, organic alkali metal compounds are suitable such as phenyllithium, naphthalene sodium or Sodium methylate or Lewis acids such as boron trifluoride, Aluminum chloride or tin tetrachloride.

Finally, ethylenically unsaturated compounds can also be polymerized using metal complexes. Therefor suitable complexes are, for example, those of Aluminum or titanium (Ziegler-Natta catalysts).

Difunctional monomers capable of polycondensation are, for example, acids such as adipic acid, terephthalic acid, amines such as hexamethylenediamine, phenylenediamines, alcohols such as ethylene glycol, butanediol, halogens such as phosgene or dimethyldichlorosilane or heterofunctional compounds such as ω- aminoundecanoic acid.

The polycondensation is preferably in the form of a melt condensation carried out, the monomers without addition of a diluent heated to approx. 200 to 300 ° C will. In addition, the polycondensation can also be used as a or interfacial polycondensation.

Suitable monomers for polyaddition can be, for example, anhydrides such as maleic anhydride, phthalic anhydride, isocyanates such as tolylene diisocyanate, epoxides such as epichlorohydrin or lactams such as ω- caprolactam. Processes suitable for carrying out polyadditions are based on the procedures mentioned above for polycondensation.

The term "polymerization" is to be understood in the broadest sense. This includes z. B. the further polymerization or cross-linking polymeric materials, e.g. B. of prepolymers, the homo-, co- and terpolymerization of simple  Monomers and also the combination of the above Types of reactions.

As lyotropic phase-producing compounds are, for. B. that are capable of forming such phases in solutions, for example, in Gan-zuo et al., Mol. Cryst. Liq. Cryst. Letters 72 (1982) 183 or in Campbell et al., Mol. Cryst. Liq. Cryst. 95 (1983) 45 described compounds, without being limited to it.

It is not necessary that the in the invention Process already used compounds with the polymerizable Compounds form lyotropic phases. Much more may also have the ability to form lyotropic phases only in a "quasi-lyotropic" order of the polymer phase express.

A preferred group of lyotropic phase generating compounds is represented by formula I

Nap-NH-CO-NH-Phe-COOR (I)

wherein

Napunsubstituted or by one capable of polymerization Radical substituted naphth-1 or naphth-2-yl, Phe1,2-, 1,3- or 1,4-phenylene and Straight-chain or branched alkyl with up to 30 carbon atoms

means.

The polymerizable groups substituting the naphthalene residue for example -CH = CH-, -OH, -SH, -NH-, -COOH or -CH = CH-. By one of these functional groups substituted compounds of the formula I can according to the methods of polymerization mentioned above, Polymerized polycondensation or polyaddition into the anisotropic polymers will.  

Compounds of the formula I in which Nap is unsubstituted naphth-1-yl, Phe 1,4-phenylene and R C₅-C₂₅-alkyl are preferred. Such Compounds of the formula I are known and can be prepared according to known ones Methods as described for example in DE 20 09 600 getting produced.

Another preferred group of lyotropic phase generating compounds is represented by Formula II

wherein

X¹ to X⁶ each independently of one another H or an alkyl group with up to 30 carbon atoms, including one or two non-adjacent CH₂ groups by a group from the group -O-, -S-, -O-CO-O-, -CH = CH-, -NR-CO-, -CO-NR-, -O-CO-NR-, -CO-, -CO-O-, -O-CO-, -CO-S-, -S-CO-, -SO-, -SO₂- and 1,4-phenylene can be replaced, and Represent RH or C₁-C₆-alkyl,

wherein at least two of the substituents X¹ to X⁶ of H are different.

Such compounds of formula II are known and can by known methods, such as in DE 33 32 955 and Billard, Sadashiva, Pramana 13 (1979) 309, getting produced. The use of connections of the Formula I and / or II for the production of anisotropic polymer materials thus represents a preferred embodiment of the present invention.  

Compounds of formula II in which X¹ to X⁶ are each independent from each other mean NRR¹, where R is the above has the meaning given and R¹ is an alkyl group with bis to 30 carbon atoms means one or two not neighboring CH₂ groups by -O-, -S-, -SO-, -SO₂-, -O-CO-, -CO-O-, -NH-, -N (C₁-C₄-alkyl), -CO-, -CO-S-, -S-CO- or -CH = CH- can be replaced, find particularly preferred in the process according to the invention for producing anisotropic Polymer materials use. Such connections are known, e.g. B. from Backer, from Baan, Rec. 56 (1937) 1175 or can be made by known methods.

If the lyotropic phase producing compounds at least a -CH = CH-, -OH, -SH, -NH-, -CO-OH, -CO-SH or contain other groups capable of polymerization, so can make these compounds anisotropic in the making Polymer materials are polymerized into this. A chemically or physically induced migration of the lyotropic Phase-producing compounds from the hardened anisotropic This effectively prevents polymer materials. The use for the production of anisotropic polymer materials of compounds producing lyotropic phases, which contain polymerizable groups another object of the present invention.

Designed to carry out the method according to the invention yourself. Obtained by simply dissolving or stirring Mixtures of polymerizable compounds and lyotropic Phasing compounds are described in the above specified way z. B. by heating, irradiation or polymerized by adding an initiator. You can do that Polymerization even in the presence of a non-polymerizing Carry out solvent. Suitable as a solvent all indifferent solvents, such as. B. ether like Diethyl ether, tetrahydrofuran or dioxane or hydrocarbons such as benzene, toluene or xylene. The polymerization in the non-aqueous phase represents another object of the invention.  

The photopolymerizable compounds or systems can be stabilized in the usual amounts by adding known thermal inhibitors and antioxidants, such as hydroquinone or hydroquinone derivatives, pyrogallol, thiophenols, nitro compounds, β- naphthylamines or β- naphthols, without the anistropia of the polymer materials according to the invention being appreciable is affected. Such additives are primarily intended to prevent premature polymerization during the production of the systems by mixing the components.

Furthermore, light stabilizers, such as Benzophenone derivatives, benzotriazole derivatives, tetraalkylpiperidines or phenylsalicyclate.

Depending on the intended use, fillers such as talc, Gypsum or silica, fibers, organic additives, such as thixotropic agents, leveling agents, binders, lubricants, Matting agents, plasticizers, wetting agents, silicones to improve the surface quality, anti-floating agent or small amounts of solvents be added.

The ratio of polymerizable compounds to the Compounds producing lyotropic phases are widely used Limits can be varied. Usually about 0.1 to 80%, preferably 0.5 to 50%, especially 1 to 15%, lyotropic Phased compounds added.

The present invention furthermore relates to anisotropic obtained by the process according to the invention Polymer materials. They are characterized by advantageous Optical, magnetic and / or electrical values Anisotropy and advantageous mechanical, for example elastic or plastic, and / or thermal properties.  

Because of their typical polymer properties, such as ability for layer, film and fiber formation as well as light Deformability opens up for the invention anisotropic polymer materials have a wide range of applications.

These properties can be achieved in a manner known per se Copolymerization or mixing with other components, by varying the molecular weights, by adding the various inorganic or organic additives and metals and many more, the polymer expert common treatments are modified.

The polymer materials according to the invention can be used as Starting material for the production of organic glasses with anisotropic properties that can be modified over a wide range use.

Such applications arise, for example the sector of light and solar collectors or at organic phototropic glasses. An important field of application also opens up in the field of optical storage.

Further applications open up on the Field of magnetic storage. Particularly suitable the compositions of the invention also as Matrix for substances with non-linear optical properties for the production of "non linear" optical Components.

The following examples serve to explain the invention:  

Example 1

A mixture of 4 g (38.4 mmol) of styrene, 0.4 g of hexakis (hexadecanylamino) benzene and 0.16 g (1 mmol) of azo-bis-isobutyronitrile is gassed with nitrogen for 20 h heated to 70 ° C. A brittle polymer is obtained, which has strong birefringence under the polarizing microscope shows.

Example 2

A mixture of 5.6 g (100 mmol) of isobutylene, 0.3 g of hexakis (heptadecanylamino) benzene and 0.1 g one of boron trifluoride and traces of water obtained catalyst is left for 24 h heated to 50 ° C. The polymer obtained shows strong birefringent properties.

Example 3

A mixture of 5 g (50 mmol) of methyl methacrylate, 0.25 g dibenzoyl peroxide and 0.5 g hexakis (dodec-11-enoyl-amino) benzene is heated to 65 ° C for 18 h. The received Polymer is highly birefringent.

Example 4

A solution of 0.4 g of N- (1-naphthyl) -N ′ - [4- (2-octyl-dodecyloxycarbonyl) phenyl] urea, 0.33 g azo-bis-isobutyronitrile and 4 g of dodecyl methacrylate is heated to 70 ° C. for 16 h. The polymer shows strong birefringent properties.

Claims (6)

1. A process for the preparation of anisotropic polymer materials by conventional polymerization of polymerizable compounds, characterized in that the polymerization is carried out in the presence of at least one nonionic, lyotropic phase-producing compound. 2. The method according to claim 1, characterized in that the lyotropic phase-producing compounds polymerizable Groups included. 3. The method according to claim 1, characterized in that the polymerization was carried out in the non-aqueous phase becomes. 4. Anisotropic polymer materials according to claim 1, available by customary polymerization of polymerizable compounds in the presence of at least one non-ionic, lyotropic phase producing compound. 5. Anisotropic polymer materials according to claim 4, characterized characterized in that the polymerization in non-aqueous Phase is carried out. 6. Use of anisotropic polymer materials according to claim 4 as optical media in electronics or as organic Substrates in fiber and film technology.