ES2324806B1 - SILOLATED COPOLYMERS WITH SILSESQUIOXAN GROUPS, ITS PREPARATION AND USE AS A HIGH PHOTOSTABILITY LASER MATRICES. - Google Patents

Abstract

Silylated copolymers with silsesquioxane groups, its preparation and use as high laser matrices photostability

The incorporation of silsesquioxane groups into copolymer is carried out from monomers with a number polymerizable double bonds variable per molecule of silsesquioxane, from one to twelve. The copolymers obtained, linear and crosslinked, they have excellent properties optical and high photostabilities, properties that make them especially applicable as solid matrices for manufacturing of laser light emitters when they are incorporated during the polymerization process a soluble laser dye in the reaction medium and in the final copolymer obtained. The laser emitters thus obtained have higher efficiencies to those obtained with commercial dyes, both in solution liquid, as in other solid matrices, the high being notable photostability presented by these silylated matrices, even under extreme working conditions.

Description

Silylated copolymers with silsesquioxane groups, its preparation and use as high laser matrices photostability

Technical sector

One of the most significant application and consumption sectors of synthetic polymers is that of Optics. Thus, its most common applications range from the manufacture of conventional optical components, such as lenses, diffraction nets, filters, polarizers, ..., and its commissioning in glasses, sunglasses and correctors, contact lenses, rigid, soft, oxygen permeable, permanent and disposable, even intraocular lenses, which by its biocompatibility represents a clear example that its importance goes beyond that of being a simple material, for the function they fulfill. Complementary examples of other more specific developments and applications are found within Optoelectronics, as well as within the field of Optics, many of them based on the non-linear optical behavior of certain polymers. Although initially the use of synthetic polymers in various applications within the field of Optics was driven, mainly, by the low price of these materials compared to traditional inorganic glasses, however, subsequently, their use and consumption was expanded in many other applications due, in addition, to a whole series of advantages over inorganic glasses; advantages based on the intrinsic properties of these materials, such as their low weight, easy machining and polishing, greater resistance to breakage, low transformation temperature, etc,
etc.

However, compared to glasses Conventional inorganic, its main disadvantages lie, for certain applications, in its low scratch resistance and Its low thermal resistance. Trying to improve these two properties of synthetic polymers, as well as other properties related, considerable effort has been made researcher aimed at structurally modifying those synthetic polymers that have adequate properties optics, mainly: by copolymerization of different monomers; by crosslinking those polymers and copolymers of proven interest in their optical properties, as well as per surface coating or surface treatment by ultraviolet radiation or electron beams. Also, new hybrid polymers have been developed organic-inorganic, following a process sol-gel, trying to combine the same material properties of organic polymers and inorganic glasses. All these advances and developments have allowed us to improve and expand considerably the number of applications of polymers synthetics within the field of optics. However, certain applications impose even greater demands, mainly on regarding its thermal properties; properties that polymers are still far from being able to reach those of other materials conventional, as they are, in addition to metals and ceramics, and specifically in optical applications, that of glasses inorganic

A characteristic of synthetic polymers, related to its thermal properties, is its behavior as insulator, both thermal, electrical and acoustic, characteristics which in turn are fundamental in a whole series of applications of these materials It is precisely this insulating character that determines the margins of use of synthetic polymers in those optical applications where the incident light on they are partially absorbed, either directly, by some chromophore present in the polymer structure, or indirectly, through some additive incorporated into it. In both cases, the part of the absorbed energy that is released at medium in the form of heat presents the inconvenience of its poor dissipation, as a consequence of the insulating nature of these materials, which can cause thermal degradation, and / or the additives incorporated therein, as a consequence of the high temperatures reached locally in areas where the light hits. This inconvenience turns out to be a factor limiting when using synthetic polymers such as solid matrices in certain optical components, such as optical filters, waveguides and dye lasers in state solid, among others. It is in this last application of polymers as a solid state dye laser generating matrix, where thermal stability is the determining factor of the possible use of these materials on an industrial scale and commercial.

Focusing on this last application and with the objective of improving the low thermal conductivity of polymers synthetic in general, and more specifically that of those polymers potentially usable in optical applications, we have developed a series of new polymers through the incorporation into its silica structure following different strategies. The choice of silica has been based on its excellent optical properties, high thermal stability and, fundamentally, in its high thermal conductivity.

State of the art

Dye lasers are used today in many different fields, both industrial and medical. As an example, in the field of Medicine, these types of lasers are increasingly used in different treatments and therapies, including their recent application for the selective destruction of cancerous tissues, in the so-called photodynamic therapy, as well as in the detection and tumor diagnosis. However, the use of these dye lasers implies the use of a dye in liquid solution, which entails a series of drawbacks and limitations, such as: the need to have to use large volumes of organic solvents, some of which are toxic, volatile and flammable; having to maintain a constant and uniform flow of these solutions within the laser cavity; having to periodically renew this solution of the dye, when it degrades during its continued use, or replace it when the emission wavelength needs to be changed, as well as another series of tedious operations that occur when cleaning the cavity and eliminate said solutions, without forgetting the complexity of the design and the auxiliary instrumentation required by the pumping of said solutions to the laser cavity. All these inconveniences entail serious limitations to their intensive use, as well as their extension to other applications. Therefore, it is of great technical interest to be able to have solid-state dye lasers, since such inconveniences will be avoided because of the advantages that such solid lasers entail over liquid lasers, since, in addition to being more compact, smaller , lighter, and therefore more manageable, allow to work in total absence of solvents, which is of particular importance in their clinical use, while requiring minimal maintenance, and can also change the laser emission interval quickly and simple. Other additional advantages derived from the use of a dye laser in the solid state, although no less important, are the freedom of design of the laser cavity and its low
price.

On the basis of this evident interest, a considerable research effort has been carried out, at international level, directed both to the study of the photophysical and photochemical processes put into play when the laser dyes are in a solid medium, as to the synthesis of new dyes and laser materials more efficient and, thermally and photochemically, more stable. Although a variety of materials such as matrices of laser dyes have been studied, ranging from solidified solvents at low temperature, jellies, molecular organic crystals, inorganic glasses ..., it has been the polymers (organic and organic-inorganic hybrids) that they have better potential to be operational at industrial and commercial level, as demonstrated by the work and results achieved during the last decade (A.Costela, I. García-Moreno, R. Sastre, Materials for solid-state dye lasers , in Handbook of Advanced Electronic and Photonic Materials and Devices, Ed. Academic Press, San Diego, CA, 2001).

One of the directions of work followed to improve the photostability of these materials has been the development of a whole series of new polymeric matrices, linear and crosslinked, in which by co-polymerization we introduced covalently the dye molecules, thus improving the Shelf life of these new lasers, as well as the whole series of advantages outlined above for solid state dye lasers (ES 9501419 , 1995 and USA 6,281,315 2001 ).

Likewise, a systematic study has been carried out on the structural modification of the substituents of dipyrrometic dyes, with the aim of improving their properties and photostability. To this end, we focus our efforts on establishing the substitution effect at position 8 of the pyromethenic ring, introducing, initially, both acetoxypolymethylene groups and methacryloxypolymethylene groups, which were used as model dyes and monomer dyes. These new dyes presented, both in liquid solution and in solid matrices, a better laser efficiency and a remarkable higher photostability, than the corresponding commercial laser dyes when they were covalently bound to a polymer ( ES 19990001540 ; A. Costela., I. García- Moreno, F. Amat-Guerri, M. Liras, R. Sastre, Appl. Phys. B , 76, 365, 2003 , and M. Álvarez, F. Amat-Guerri, A. Costela, I. García-Moreno, M Liras, R. Sastre, Appl. Phys. B , 80, 993, 2005 ). Next, we also incorporate in said position 8 of the indacenic ring, only a p-phenylene-acetoxypolymethylene group and a p-phenylene-methacryloxypolymethylene group, whose photophysical properties and their laser evaluation demonstrated that, both in liquid solution saturated in air, as in its solid copolymers with methyl methacrylate, its laser emission efficiencies and photostability were markedly improved (I. García-Moreno, A. Costela, R. Sastre, F. Amat-Guerri, M. Liras, F. López-Arbeloa , J. Bañuelos, I. López-Arbeloa, J. Phys. Chem. A , 108, 3315,
2004 ).

Subsequently, trying to improve the thermal properties of these polymeric matrices, new organic-inorganic hybrid polymers were also developed, obtained by simultaneous polymerization-polycondensation synthesis procedures, which have allowed to achieve even greater photostabilities [Costela, A., García-Moreno , I., Gómez, C., García, O., Garrido, L. and Sastre, R., Highly efficient and stable doped hybrid organic-inorganic materials for solid-state dye lasers, Chem. Phys. Lett . 387 : 496-501 (2004); Costela, A., García-Moreno, I., Gómez, C., García, O. and Sastre, R., Enhancement of laser properties of pyrromethene 567 dye incorporated into new organic-inorganic hybrid materials, Chem. Phys. Lett . 369 : 656-661 (2003); Costela, A., García-Moreno, I., Gómez, C., García, O., and Sastre, R., Environment effects on the lasing photostability of Rhodamine 6G incorporated into organic-inorganic hybrid materials, Appl. Phys. B 78 : 629-634 (2004); Costela, A., García-Moreno, I., García, O., del Agua, D. and Sastre, R., Structural influence of the inorganic network in the laser performance of dye-doped hybrid materials, Appl. Phys. B. 80 : 749-755 (2005); García-Moreno, I., Costela, A., Cuesta. A., García, O., del Agua, D. and Sastre, R., Synthesis, Structure, and Physical Properties of Hybrid Nanocomposites for Solid-State Dye Lasers, J. Phys. Chem. B 109 : 21618-21626 (2005 )]. Likewise, trying to improve photostability even more, as well as its thermo-optical and mechanical properties, other new organic-inorganic hybrid polymers were obtained from mesoporous silica or aerogels, consisting of three-dimensional networks of open pore silica silica of nanometric size, which are they flood with the appropriate monomer-laser dye formulations, to be subsequently polymerized in situ , in a controlled manner, thus allowing to obtain more efficient materials in their laser emission and highly photostable, mainly when the polymers obtained within the mesoporous silica matrix were fluoridated in nature [Costela, A., García-Moreno, I., Gómez, C., García, O., Sastre, R., Roig, A., and Molins, E., Polymer-Filled Nanoporous Silica Aerogels as Hosts for Highly Stable Solid-State Dye Lasers, J. Phys. Chem B 109 : 4475-4480 (2005). Four. Five; García, O., Sastre, R., del Agua, D., Costela, A., García-Moreno, I., and Roig, A., Efficient optical materials based on fluorinated-polymeric silica aerogels, Chem. Phys. Lett . 427 : 375-378 (2006); Costela, A., García-Moreno, I., del Agua, D., García, O. and Sastre, R., Highly photostable solid-state dye lasers based on silicon-modified organic matrices, J. Appl. Phys . 101 : 073110 (2007)].

All these results and developments allow obtain sufficiently efficient and stable materials such as to be used, both industrially and commercially, as active means for the emission of laser light. The main advantage of incorporating silica in these Materials lies in the substantial improvement of its conductivity thermal, which favors the dissipation of local heat released during the process of excitation or pumping of the dye, avoiding thus, to a great extent, the thermal degradation of the dye and, therefore, extending the service life of the generator To be. However, in both families of these hybrid polymers organic-inorganic, although silica is found homogeneously distributed in the final material, the domains of this inorganic phase can lead to undesirable phenomena in regarding its interference with light, as well as the segregation of  dye from said domains, which remains dissolved only in the domains of the organic polymer. Therefore, and also considering the synthesis difficulties of both families of polymers, we consider the synthesis of new polymers in which we have incorporated silica level molecular, in order to obtain intrinsically more materials homogeneous in order to avoid such inconveniences and improve even more its thermal conductivity and its optical properties.

Description of the invention

The hydrolysis and subsequent condensation of trifunctional silanes (silicon trialkoxides) lead to the formation of polyhedral clusters of general formula (RSiO 1,5), called Silsesquioxanes , also known commercially as POSS (the acronym in English for Oligomeric Polyhedra of Silsesquioxanes):

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one

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R being a substituent of organic nature Although in these compounds silicon is coordinated with three oxygen atoms while on silica This coordination is fourfold, because of the similarity between the two has considered Silsesquioxanes as a silica of polyhedral structure or prismatic

Given the improvements achieved in the laser photostability, previously described, when incorporating silica in the polymeric structure of hybrid matrices used as laser light emitters, we start from the hypothesis of that if silica could be incorporated at the molecular level, it could reach the full potential that silica can bring, with the main objective of increasing the thermal conductivity of the matrix and thus improve its thermo- and photostability. Other advantages additional of great interest, from the point of view of others potential applications of these new materials within the Optics field, would be those derived from the properties that it can also contribute the presence of this form of silica in concerning its excellent light transmission ultraviolet-visible index of refraction, stability, resistance ... while these materials can be obtained at temperatures close to room temperature, what which allows incorporating organic compounds into its structure, which otherwise it would not be possible, considering the high temperatures necessarily used in the synthesis and / or modification, transformation and molding of silica; all of which opens a range of new possibilities for applications these materials

Since the main feature pursued in obtaining a solid matrix as an active medium in the laser emission of an organic dye is its homogeneity optical, the prerequisite is the solubility and compatibility of the monomers to be used. Therefore, the appropriate Functionalization of the starting Silsesquioxane is essential, with in order to achieve its total solubility in the comonomer or selected comonomers. From a general point of view and to the once simplified, obtaining the matrices object of the The present invention is based on the copolymerization of different monomers, of which at least one of them carries as polymerizable double bond substituent a silsesquioxane group (structure I), or it consists of a functionalized silsesquioxane with a variable number of polymerizable double bonds, greater than one and up to a maximum of eight, ten or twelve polymerizable groups (structure II):

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in which the substituent R of the structure I, can be any aliphatic organic group or aromatic, properly selected to favor its solubility  and compatibility with other organic monomers conventional.

Although as a polymerizable group of Silsesquioxane is considered any unsaturated group, preferably the best results are those obtained with doubles vinyl, acrylic and methacrylic bonds, these two being last unsaturated groups with which they have managed to reach The best optical properties. Also, with regard to comonomers employable in this invention, the best results they have also been obtained with acrylic and methacrylic monomers, with one to four unsaturated groups per comonomer molecule. The use of polyfunctional monomers leads to obtaining crosslinked polymers with a degree of crosslinking of variable extent and dependent on the proportion or concentration of the monomer or polyfunctional monomers used, as well as the degree of functionality of them. Since the main differentiating characteristic of the materials object of the This patent is the use and use of carrier monomers of silsesquioxane structures I and II, the proportion or concentration of this type of monomers is determinant of its properties and solid matrix behavior of those dyes Usable for stimulated laser light generation. Although the proportion or concentration of silsesquioxane monomers, with structure I or II, may vary within wide ranges, without However, we have verified that the copolymers with the best laser properties are obtained when its concentration is between 1 and 50% by weight, with respect to the total volume  of the mixture of starting monomers.

The initiation of the polymerization process is can carry out by conventional methods and procedures used in macromolecular synthesis; namely: radicals free or ionic route, both thermally and photochemically or redox, in solution, suspension, emulsion, interface, block or mass. The best results have been achieved by block polymerization by thermal initiation via radicals free. The employable initiators for the generation of radicals free are all those also commonly used in polymerization processes, the most appropriate being the type peroxide and hydroperoxide, as well as aliphatic azo compounds, having been with the initiator azobis-isobutyronitrile with the best results have been obtained, when it is used at a concentration between 0.1 and 5% by weight, with respect to the monomer mixture. It is also advisable to carry out polymerization in an inert atmosphere, such as low nitrogen or argon atmosphere, or under vacuum (at least 15 Pa)

Once the initiator is conveniently dissolved in the monomer mixture, the laser dye is incorporated selected according to the laser emission wavelength that is desired. The concentration to be used of the laser dye comes specifically determined by its molar absorption coefficient at the excitation or pumping wavelength, due to its optical density, by the configuration of the laser cavity and by the type of pumping, transverse or longitudinal, of said cavity. Therefore, in each case, for each dye it is necessary to carry out previously the optimization of its concentration, according to the parameters indicated.

A determining and vital aspect is that of the solubility of the laser dye, both in the mixture initial of the starting monomers, as in the solid polymer final obtained, since even a partial insolubility of the dye leads to the impossibility of generating laser light, or well to a material with a low stability that excludes its use Commercial for this application. To that end, it is necessary to it is essential to ensure the total prior solubility of the dye in the initial monomer mixture, thus being necessary choosing the nature and proportions of the monomers of heading, as well as using the appropriate methods to ensure and facilitate its total solubility, having turned out to be of great Efficiency for this purpose the use of ultrasound. Once dissolved the dye in the monomer mixture, it is advisable to microfiltrate the resulting solution with an inert membrane of pore size of 0.2 microns or less, in order to eliminate possible traces of the laser dye that have not dissolved, as well as other possible particles and solid impurities that might exist in the means, medium.

The final solution obtained once microfiltered, poured into a mold with the appropriate dimensions to obtain, once carried out its polymerization, a piece suitable to be machined to the shape and dimensions chosen for its adaptation to the laser cavity. The mold used can be any of the materials commonly used in molding by casting of a plastic material, taking special care in your choice with a view to facilitating the subsequent demolding of the piece, once the polymerization process is finished.

Since the laser properties of the final material obtained turn out to be equally dependent on the optical homogeneity thereof, it is necessary to optimize the polymerization process conditions in each case in order to avoid possible refractive index differences within the material, following the procedures, methods and conditions described in our ES 19990001540 .

Once obtained the polymeric matrices carriers of laser dyes in proportions and adequate concentrations, it is demoulded and machined, following the usual procedures in the machining of materials, until reaching the geometric shape and dimensions desired, as well as a subsequent polishing of said piece until achieve a laser quality finish or at least quality optics.

The physical properties of the materials obtained are a function of the corresponding composition copolymers, to be noted, for the purposes pursued in the present patent, the increase experienced by two properties thermal by increasing the proportion or content in the copolymer in silsesquioxane units, such as the transition temperature Vitreous and thermal conductivity. So, the temperature of glass transition of methyl methacrylate copolymers with Silsesquioxane monomers, doubles when passing from homopolymer (approx. 100 ° C) to a copolymer with 33% in weight / volume of silsesquioxane octamethylmethacrylate (approx. 190 ° C). What is even more important, is the increase you experience thermal conductivity, which grows linearly with the content of silsesquioxane in the copolymer, according to the values listed in the attached Table 1.

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TABLE 1 Thermal conductivity of different copolymers of MMA with silsesquioxane octamethacrylate (8MMAPOSS)

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Said increase in thermal conductivity implies a parallel increase in its laser emission efficiency, passing from 12% for polymer without silsesquioxane to, for example, 64.8% for the 33% copolymer in silsesquioxane. Said values are even superior to that of this same dye, PM 567, in liquid solution (approx. 36%), which are the maximum efficiencies achievable in the current commercial lasers of this dye. What is even more important, is the sharp increase in its stability under irradiation when pumped transversely to 532 nm, with a frequency of 10 Hz and an energy of 5 mJ, conditions under which its emission efficiency is maintained, after 100,000 shots, at a level of 90 to 100% of its value initial. This stability has been proven experimentally that it is also maintained even using pumping conditions more drastic, as has been the use of frequencies of 30 Hz, thus overcoming the behavior of the dye in solution liquid, which greatly guarantees the commercial use of these new materials in the manufacture of dye lasers in solid state.

For the evaluation as an active medium for the generation of laser radiation of these new materials, object of the present patent, different assemblies of those commonly used in known laser devices can be used, although in the present case the two described in our ES 19990001540 , as well as the cavities, pumping system and detailed procedures therein.

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Examples of embodiment of the invention

As representative examples, but not limiting, of the materials object of this patent, as well as of its properties, behavior and application, then it describes obtaining these copolymers of Silsesquioxanes, as well as the evaluation as laser light emitters of the copolymers obtained.

Example 1 Obtaining Silsesquioxane Copolymers

Taking the laser dye as a reference Commercial Pyrometene 567, a 1.5 mM solution of the same, in a mixture of silsesquioxane octamethylmethacrylate and pure methyl methacrylate, in varying proportions and between 1 and 50% weight / volume in both monomers (10 ml). The initiator is added to each of these solutions  azobisisobutyronitrile (10 mg; 0.06 mmol), which is solubilized by agitation and subsequent treatment in a bath ultrasound Then these solutions are microfiltered with a 0.2 micron pore size membrane and poured over 12 cm diameter polypropylene cylindrical molds interior, within which the resulting solution is deoxygenated by pure argon or nitrogen bubbling, immersing in these solutions a capillary for about ten minutes The molds are closed and sealed under an inert atmosphere and are maintained at 40 ° C for 48 hours. After this time, the solutions will have solidified, then the temperature up to 50 ° C, temperature at which the molds for at least 24 hours. Then, in order to destroy the remains of the initiator that had not reacted, it the temperature rises again slowly (50ºC / day), until reaching 80ºC, staying at this temperature for 2 more hours, then slowly cool both molds until reaching room temperature, in order to avoid freezing of residual stresses that could affect the optical quality of the material obtained, being able then to unmold the pieces.

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Example 2 Evaluation of the new copolymers as radiation emitters To be

The laser evaluation of the materials obtained following the procedure described in the previous example, was carried out once conveniently machined and polished in the form of cylinders 1cm high and 1cm in diameter, with a cut parallel to its axis, with object of obtaining a flat lateral surface. The device used in this evaluation was the one described in ES 19990001540 .

Table 2 shows the values of the Laser parameters: emission wavelength, efficiency and stability of different copolymers obtained based on contained in the silsesquioxane octamethylmethacrylate monomer, following the procedure described in example 1.

TABLE 2 Laser parameters of different MMA copolymers in function of the content by weight in the octametacrylate monomer of Silsesquioxane (8MMAPOSS)

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The values obtained for laser efficiencies they are between 46 and 65%, with some Stabilities, after irradiation with 100,000 shots at 532 nm with an energy 5mJ per shot at 10 Hz. These values of Efficiency in their laser emission are superior even to those of this same dye in solution in ethanol (approx. 36%), while their high photostability enables them to be implemented commercial as dye laser light emitters in the state solid.

A significant improvement in the stability of those copolymers with the highest proportion in the silylated monomer it was achieved through a postpolymerization treatment, consisting of keeping said samples at a temperature of 90 ° C for at least one week, in order to activate the doubles remaining links that would not have polymerized, which reflects in stability improvements of the order of 10%. With in order to contrast the high stabilities achieved, it was submitted to the copolymer with a silsesquioxane weight content of 13% a irradiation under more drastic conditions, using it a pumping frequency of 30 Hz, checking that even after 100,000 shots kept their emission efficiency at 100%.

Therefore, the use of new Materials such as laser light emitters, object of the present invention patent, has shown that they have some efficiency, tunability and photostability values that make them viable to be used as laser light emitters, substantially improving other polymer matrices previously described.

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Example 3 Extension of the use of these matrices to other dyes lasers

In order to demonstrate the applicability of these matrices with any of the laser dyes used commercially, new copolymers with a content were synthesized in octamethyl methacrylate of 13% by weight, following the procedure described in example 1, but now adding to each sample of copolymer one of the five most commercial laser dyes Representative: Pirrometene 569, Rhodamine 6G, Red Perylene and Coumarin 503, in addition to Pyrometene 567. Concentrations of each of them were chosen according to their coefficient of molar absorption to reach an optimum optical density at 532 nm, in order to obtain maximum efficiency in each case under experimental conditions of excitation or pumping described in the Previous example. The experimental values obtained are collected in the attached Table 3.

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TABLE 3 Laser evaluation of different dyes to be incorporated into the MMA / 8MMAPOSS-13 copolymer P

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These results show that both high  laser efficiencies reached, when the dye is truly dissolved in the solid matrices of the copolymer with silsesquioxane octamethylmethacrylate, they are superior or, as minimum, equal to those obtained with the same dyes in dissolution. As for the high photostabilities obtained, show that these materials are also usable with any laser dye, which is soluble therein, such as solid laser light emitters.

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Example 4 Influence of the functionality of the carrier monomer Silsesquioxane

In order to illustrate the influence it has the number of double bonds of the group carrier monomer Silsesquioxane, two copolymers were obtained with the monomer with a single double methacrylic bond (structure I) and another with the monomer with eight double methacrylic bonds (structure II), both at a concentration of 13% with respect to total volume of the monomer mixture. The conditions of synthesis, concentration of dye PM 567, as well as its laser evaluation, were identical for both samples and with the described in the previous examples.

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TABLE 4 Comparison of the laser parameters evaluated in function of the number of methacrylic groups present in the silylated monomer (xMMAPOSS)

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Although efficiency and stability values they were both of the same order, those obtained for the copolymer of Silsesquioxane octamethylmethacrylate were superior by 20 and in 10%, respectively, with respect to those obtained with the monomer with only one methacrylate group. These differences are assignable to the crosslinking of the copolymer obtained with this polyfunctional monomer, versus the linear copolymer obtained with the First monomer

Claims (7)

1. Linear silylated copolymers with silsesquioxane groups, characterized in that at least one of the comonomers used in obtaining it has as a substituent of its polymerizable double bond a Silsesquioxane group (structure I): 8 where R are hydrogens or any organic, aliphatic or aromatic.

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2. Silylated crosslinked copolymers with silsesquioxane groups, characterized in that at least one of the comonomers employed in obtaining it has a functionalized Silsesquioxane group with a variable number of polymerizable double bonds, greater than one and up to a maximum of eight groups per molecule (structure II ): 9 3. Silylated crosslinked copolymers with silsesquioxane groups, linear or crosslinked according to claims 1 and 2, further characterized in that the double bonds of the carrier monomers of the Silsesquioxane group, as well as those of their comonomers, can be any double polymerizable bond in a number variable, from one to eight, although preferably the best results are those obtained with vinyl, acrylic and methacrylic double bonds, the latter two unsaturated groups with which the best optical properties have been achieved. 4. Silylated copolymers with silsesquioxane groups according to claims 1, 2 and 3, characterized in that the concentration of silsesquioxane monomers with structure I or II varies within wide ranges, although copolymers with better laser properties are obtained when their concentration is It is between 1 and 50% by weight, based on the volume of the total mixture of starting monomers. 5. Procedure for obtaining silylated copolymers with silsesquioxane groups according to the preceding claims, characterized in that the block polymerization is carried out by thermal initiation via free radicals; using as initiator, those of the peroxide and hydroperoxide type, as well as the aliphatic azo compounds, preferably azobis-isobutyronitrile, at a concentration of between 0.1 and 5% by weight, with respect to the monomer mixture. 6. Use of the above copolymers silylated, according to claims 1 to 5, in those applications optics where polymeric materials with good materials are required optical properties, high photostability, as well as greater stability and thermal conductivity than those of polymers conventional commercials. 7. Use of the above copolymers silylated with silsesquioxane groups according to claims 1 to  6, in applications where thermal stability is determinant, such as its use to obtain matrices high efficiency dye laser light emitters and stability, when these solid matrices are incorporated, before or during its polymerization, any laser dye, provided that they are soluble in the initial mixture of monomers and in the final polymer obtained.