RU2767650C1 - Polysiloxane compositions and elastomeric materials with high dielectric permeability based thereon - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to the field of production of elastomeric materials based on polysiloxane compositions and can be used in high-technology fields of electrical engineering and robotics as an electrically active material in creation of sensors, actuators, artificial muscles. Proposed is a polysiloxane composition including polydiorganosiloxane with terminal hydroxyl groups and/or analogue thereof with terminal 3-aminopropyl diethoxysilyl groups by the formula (I), wherein X represents a hydrogen atom, -Si(OC₂H₅)₂(CH₃)₂NH₂; R¹ represents CH₃, C₂H₅or C₆H₅-; R² represents CH₃-CH₂=CH - or C₂H₅-; one or multiple functional metallo-siloxanes by the formula (II), wherein M is a bi-, tri-, or tetravalent metal selected from Zn, Zr, Ti, and Fe(III); p+m corresponds to the valency of the metal, provided that p≠m, wherein m equals 1, 2, 3, or 4; R and Alk independently represent C₁-C₄–alkyls; R’ represents C₆H₅-, CH₂=CH-, SH(CH₂)₃-, CH₂=CHC(O)O(CH₂)₃-, CH₂=C(CH₃)C(O)O(CH₂)₃-, (III) or (IV); and ethoxysiloxane, wherein the mass ratio of polydiorganosiloxane(s) and the functional metallo-siloxane(s) is in the range from 3:0.1 to 3:2, and of the polydiorganosiloxane(s) and ethoxysiloxane is in the range from 3:1 to 3:4 pts. wt., respectively. Also proposed are a method for producing an elastomeric material, an elastomeric material produced by the claimed method, application thereof, and a method for adjusting the dielectric properties of the elastomeric material.

EFFECT: production of new elastomeric materials based on polydiorganosiloxanes with an adjustable value of dielectric permeability in the range from 3 to 100 (10 Hz) by a method ensuring production of a material containing no microdefects in the form of bubbles of residual amounts of a solvent, suitable for use in various electromechanical apparatuses.

13 cl, 1 dwg, 1 tbl, 12 ex

Description

FIELD OF TECHNOLOGY TO WHICH THE INVENTION RELATES

[001] The present invention relates to the field of obtaining elastomeric materials based on polysiloxane compositions and can be used in high-tech areas of electrical and robotics as an electroactive material when creating sensors, actuators, artificial muscles, etc.

BACKGROUND OF THE INVENTION

[002] Dielectric electroactive materials are "smart materials" that are able to change their size and/or shape under the influence of an electrical signal, as well as convert electrical energy into mechanical work [Brochu, P., & Pei, Q. (2012). Dielectric elastomers for actuators and artificial muscles. In Electroactivity in Polymeric Materials (pp. 1-56). Springer, Boston, M.A.; Carpi, F., Bauer, S., & De Rossi, D. (2010). Stretching dielectric elastomer performance. Science, 330(6012), 1759-1761]. In particular, it is known to use dielectric elastomers with deposited electrodes in flexible sensors [CN107747957A, publication date 03/02/2018; CN108253998A, publication date 07/06/2018; TW202001220A, publication date 01/01/2020; Chen, D., & Pei, Q. (2017). Electronic muscles and skins: a review of soft sensors and actuators. Chemical reviews, 117(17), 11239-11268, Huang, B., Li, M., Mei, T., McCoul, D., Qin, S., Zhao, Z., & Zhao, J. (2017) . Wearable stretch sensors for motion measurement of the wrist joint based on dielectric elastomers. Sensors, 17(12), 2708] and actuators [US8354774B2, publication date 01/15/2013; KR20050091880A, publication date 09/15/2005; EP1966840A, publication date 09/10/2008; O'Halloran, A., O'malley, F., & McHugh, P. (2008). A review on dielectric elastomer actuators, technology, applications, and challenges. Journal of Applied Physics, 104(7), 9; Pelrine, R., Kornbluh, R., Joseph, J., Heydt, R., Pei, Q., & Chiba, S. (2000). High-field deformation of elastomeric dielectrics for actuators. Materials Science and Engineering: C, 11(2), 89-100].

[003] The most widely used dielectric electroactive materials are siloxane elastomers, due to the reproducibility of cycles, a slight tendency to the Mullins effect and aging, the ability to work over a wide temperature range [Maffli, L., Rosset, S., Ghilardi, M., Carpi, F ., & Shea, H. (2015). Ultrafast all-polymer electrically tunable silicone lenses. Advanced functional materials, 25(11), 1656-1665; Kornbluh, R. D., Pelrine, R., Prahlad, H., Wong-Foy, A., McCoy, B., Kim, S., ... & Low, T. (2012). Dielectric elastomers: Stretching the capabilities of energy harvesting. MRS bulletin, 37(3), 246].

[004] However, the low value of the dielectric constant of polysiloxanes, which in the case of unfilled compositions is 2-3 regardless of frequency, necessitates the use of high voltage to activate materials based on them and, as a result, does not allow using the full potential of the mechanical properties of polysiloxane materials. Therefore, the development of new silicone materials with increased dielectric constant is an urgent task.

[005] Various approaches are known to increase the dielectric constant of siloxane elastomeric materials. Among them, two approaches are most widely used. The first is the chemical modification of silocane rubber with polar groups and the preparation of composites based on it.

[006] Elastomeric materials based on azide-containing allyl-terminated polydimethylsiloxanes modified by azide-alkyne cycloaddition reactions with 1-ethynyl-4-nitrobenzene and hydride-containing polymethylsiloxanes are known. Depending on the concentration of the modified groups, compositions can be obtained whose dielectric constant reaches 59.3 at 1 Hz. [Madsen, F. B., Yu, L., Daugaard, A. E., Hvilsted, S., & Skov, A. L. (2014). Silicone elastomers with high dielectric permittivity and high dielectric breakdown strength based on dipolar copolymers. Polymer, 55(24), 6212-6219].

[007] Known elastomeric materials based on modified 3-mercaptopropionic acid polymethylvinylsiloxane, iron chloride, forming salt ionic bonds with carboxyl groups, and ethanedithiol as a crosslinking agent. Depending on the content of ferric chloride, the dielectric constant of such compositions varies from 6 to 60 at 100 Hz. [Sun, H., Liu, X., Liu, S., Yu, B., Ning, N., Tian, M., & Zhang, L. (2020). Supramolecular silicone dielectric elastomer with high dielectric constant, fast and highly efficient self-healing at mild conditions. Journal of Materials Chemistry A.].

[008] Despite the effectiveness of chemical modification in controlling the dielectric constant of siloxane elastomer composites, this approach is characterized by a large number of intermediate stages required to obtain a polysiloxane of a given structure, as well as limited scaling, determined, in particular, by the type of chemical processes chosen for modification.

[009] A second approach to producing high dielectric siloxane elastomeric materials is to create polydimethylsiloxane composites filled with high dielectric particles or conductive particles.

[010] For example, elastomeric materials consisting of polydimethylsiloxane, barium titanate nanofibers, and graphene nanoplates are known. The dielectric constant of the composition based on polydimethylsiloxane increases from 3 to 12, regardless of frequency, with the introduction of 20 wt.% barium titanate. The introduction of graphite nanoplates leads to an increase in the dielectric constant up to 18.6. [Wang, Z., Nelson, J. K., Miao, J., Linhardt, R. J., Schadler, L. S., Hillborg, H., & Zhao, S. (2012). Effect of high aspect ratio filler on dielectric properties of polymer composites: a study on barium titanate fibers and graphene platelets. IEEE Transactions on Dielectrics and Electrical Insulation, 19(3), 960-967].

[011] Known elastomeric composite materials based on polydimethylsiloxane and carbon black, the dielectric constant of which increases to 30 at 12 GHz with a 40% filler content [Al-Hartomy, OA, Al-Solamy, F., Al-Ghamdi, A. , Dishovsky, N., Iliev, V., & El-Tantawy, F. (2011). Dielectric and microwave properties of siloxane rubber/carbon black nanocomposites and their correlation. International Journal of Polymer Science, 2011.].

[012] Patent CN106633891 [publication date 05/10/2017] discloses a high dielectric elastomer composite material based on a siloxane elastomer, consisting of polydimethylsiloxane, hardener, polyethylene glycol and conductive filler, while the mass ratio of polydimethylsiloxane to hardener is 5:1 ÷40:1, the mass ratio of polydimethylsiloxane to polyethylene glycol is 17:10÷88:1, and the conductive filler is not more than 2.7% of the total mass of other components of the mixture. The composite material has a homogeneous microporous structure, and the conductive filler is distributed at the interface between polydimethylsiloxane and polyethylene glycol.

[013] Elastomeric composite materials with high dielectric constant based on fluorinated silicone rubber with adjustable crosslink density and semiconductor filler with high dielectric constant are known [CN104830072, publication date 08/12/2015].

[014] Patent CN110358309 [publication date 10/22/2019] discloses a dielectric elastomeric composite material based on 100 wt.h. carboxyl-containing siloxane rubber, 0.5-5 wt.h. benzene-containing compounds, 0.5-5 wt.h. carbon nanotubes, 0.1-1 wt. including a crosslinking agent and 0.1-1 wt.h. catalyst.

[015] The main problems of such composite elastomeric materials and methods for their preparation is the difficulty of dispersing fillers in the matrix and obtaining homogeneous elastomers in composition. The solution to this problem can be the creation of conditions in which the formation of the filler in the matrix occurs directly during its curing. Known elastomeric siloxane composites based on polydimethylsiloxane and functional partially and fully substituted metallosiloxanes, upon receipt of which the formation of a metal-containing silica filler occurs during curing [RU 2296767C1, publication date 10.04.2007;
RU 2649392C2, publication date 10/20/2015].

[016] Functional metallosiloxanes are effective hardeners of siloxane compositions due to their activity not only as an agent for forming a three-dimensional metal oxide network, but also due to their catalytic activity in the processes of hydrolytic condensation of all components present in the system, which allows the formation of a cross-linked system at room temperature . In this case, additional filling of compositions is possible using hyperbranched polyethoxysiloxane as a liquid precursor of silica, which is also formed during the curing of the composition. The mechanical characteristics of such composites have been extensively studied, but there are no data on their dielectric characteristics.

SUMMARY OF THE INVENTION

[017] The technical problem to be solved by the claimed invention is the creation of new elastomeric materials with a dielectric constant of more than 3 (10 Hz) based on compositions including polydiorganosiloxanes and functional metallosiloxanes and a method for their preparation.

[018] The technical result achieved by the implementation of the claimed invention is to obtain new elastomeric materials based on polydiorganosiloxanes with an adjustable dielectric constant in the range from 3 to 100 (10 Hz), to create a method for their production, providing a material that does not contain microdefects in the form of bubbles of residual amounts of solvent, suitable for use in various electromechanical devices.

[019] The claimed technical result is achieved by obtaining new elastomeric materials with a dielectric constant of more than 3 (10 Hz) based on compositions containing polydiorganosiloxane with terminal hydroxyl groups and / or its analogue with terminal 3-aminopropyldiethoxysilyl groups of general formula (I)

where X is a hydrogen atom or

-Si (OC ₂ H ₅ ) ₂ (CH ₃ ) ₂ NH ₂ ,

R ¹ means CH ₃ -, C ₂ H ₅ - or C ₆ H ₅ -,

R ² means CH ₃ -, CH ₂ =CH- or C ₂ H ₅ -,

one or more functional metallosiloxanes of general formula (II)

where M is a di-, tri-, or tetravalent metal selected from the series Zn, Zr, Ti, and Fe(III),

p + m corresponds to the valency of the metal, provided that

where m is 1, 2, 3 or 4

R and Alk are independently C ₁ -C ₄ alkyl,

R' is C ₆ H ₅ -, CH ₂ =CH-, SH(CH ₂ ) ₃ -, CH ₂ =CHC(O)O(CH ₂ ) ₃ -, CH ₂ =C(CH ₃ )C(O )O(CH ₂ ) ₃ -,

или

,

or

,

and ethoxysiloxane, and the mass ratio of polydiorganosiloxane(s) and functional(s) metallosiloxanes is 3:0.1 to 3:2, and polydiorganosiloxane(s) and ethoxysiloxane from 3:1 to 3:4 wt. hours, respectively.

[020] In a particular case of the implementation of the invention, as a metal in a functional metallosiloxane, a di-, tri- or tetravalent metal selected from the series Zn, Fe(III), Zr, Ti, or preferably a tetravalent metal selected from Zr or Ti , most preferably Zr.

[021] The method for producing an elastomeric material consists in mixing polydiorganosiloxane(s) with metallosiloxane and ethoxysiloxane in a solvent, drying the resulting solution to a residual solvent content or visible signs of curing, and then curing the resulting mixture by sequentially heating it for 1 hour at a temperature of 50 ° C , at 70 °C, at 100 °C and then for 2 hours at 150 °C.

[022] It is this gradual heating mode that causes uniform evaporation of the residual solvent and the alcohol components released during hydrolysis and condensation, thereby ensuring the reproducible formation of elastomeric materials that do not contain microdefects caused by the presence of residual amounts of solvent and are suitable for use in electromechanical devices.

[023] In a particular case of the implementation of the invention, a non-polar solvent from the group of toluene, pentane, cyclopentane, hexane, benzene, cyclohexane, methylcyclohexane, or mixtures thereof can be used as a solvent in the preparation of dielectric elastomeric materials.

[024] In the particular case of the implementation of the invention, the stage of drying the resulting solution to visually determined signs of curing can be carried out at atmospheric or reduced pressure.

[025] The elastomeric material obtained in this way has an increased dielectric constant, which in particular can vary from 3 to 100 (10 Hz). The study of the dielectric characteristics showed that an increase in the dielectric constant of the resulting elastomeric materials is observed only in the presence of ethoxysiloxanes.

[026] Thus, the main advantages of the inventive dielectric siloxane elastomer materials with a dielectric constant of more than 3, in contrast to siloxane elastomer materials with a high dielectric constant, achieved by filling the compositions with particles with a high dielectric constant or conductive particles, is the formation of siloxane elastomer materials with a uniform the distribution of filler particles - silica formed from ethoxysiloxane - in the matrix, as well as the ability to control the dielectric constant over a wide range.

[027] The inventive siloxane elastomeric materials with applied electrodes are used in electromechanical devices, in particular in sensors and/or actuators.

[028] Similar to the sensor claimed in patent CN107747957A [publication date 03/02/2018], which is a dielectric elastomer made of styrene-butadiene-styrene block copolymer with electrodes deposited on 2 sides, consisting of carbon nanotubes, and insulating layers similar in composition of the dielectric elastomer, a sensor was obtained, characterized in that the material obtained in example 6 was used as the dielectric elastomer, and cross-linked polydimethylsiloxane was used as the insulating layer. The resulting sensor can withstand more than 1000 operation cycles without changing its capacitive characteristics.

[029] Based on the material obtained in example 6, an actuator similar to that described in [Pelrine, R., Kornbluh, R., Joseph, J., Heydt, R., Pei, Q., & Chiba, S. (2000). High-field deformation of elastomeric dielectrics for actuators. Materials Science and Engineering: C, 11(2), 89-100], which is the claimed material with applied circular electrodes, fixed between two Plexiglas rings. This actuator is able to withstand more than 1000 operating cycles without changing performance, while the efficiency of the actuator is 25%.

[030] The good reproducibility of the characteristics of the sensor and the actuator based on the claimed materials proves the effectiveness of the method for their preparation, which provides a material structure that does not contain microdefects in the form of bubbles of residual solvents.

IMPLEMENTATION OF THE INVENTION

[031] the Invention is illustrated by the following comparative example 1 and examples 2-12, reflecting the essence of the invention, but is not limited to them, and is also illustrated by graphic materials and experimental data presented in Table No. 1.

[032] The graphics show:

in fig. 1 dependences of dielectric constant on frequency for examples 1 and 10 of table No. 1.

Example 1 (comparison example).

[033] To obtain 1.0 g of an elastomeric material, a composition consisting of 0.75 g of polydimethylsiloxane with hydroxyl groups and 0.25 g of zirconium siloxane of the formula Zr[OSi(CH=CH ₂ )(OC ₂ H ₅ ) ₂ ] ₄ , in toluene and homogenized for about 1 minute, then the resulting solution is poured onto a substrate, kept in air at room temperature until the composition is visually cured and volatile components evaporate. Then the system in the substrate is heated in the following temperature regime: 1 h at 50°С, 1 h at 70°С, 1 h at 100°С, and then 2 h at 150°С, after which it is cooled to room temperature.

Example 2

[034] To obtain 1.0 g of a siloxane elastomeric material, a composition is prepared consisting of 0.48 g of polydimethylsiloxane with hydroxyl groups, 0.04 g of a metallosiloxane of the formula [C ₂ H ₅ O] ₂ Zr[OSi(C ₆ H ₅ )( OC ₂ H ₅ ) ₂ ] ₂ and 0.48 g of hyperbranched polyethoxysiloxane, in toluene, are homogenized for about 1 minute, then the resulting solution is poured onto a substrate, kept in air at room temperature until the composition is visually cured and volatile components evaporate. Then the system in the substrate is heated in the following temperature regime: 1 h at 50°C, 1 h at 70°C, 1 h at 100°C, and then 2 h at 150°C, after which it is cooled to room temperature.

Example 3

[035] To obtain 1.0 g of an elastomeric material, a composition is prepared consisting of 0.48 g of polydimethylsiloxane with hydroxyl groups, 0.04 g of a metallosiloxane of the formula [C ₂ H ₅ O] ₂ Zr[OSi(C ₆ H ₅ )(OC ₂ H ₅ ) ₂ ] ₂ and 0.48 g of hyperbranched polyethoxysiloxane, in toluene, are homogenized for about 1 minute, then the resulting solution is concentrated at a residual pressure of 77 mbar, poured onto a substrate and heated in the following temperature regime: 1 h at 50 ° C, 1 h at 70°C, 1 h at 100°C, and then 2 h at 150°C, after which it is cooled to room temperature.

Example 4

[036] To obtain 1.0 g of an elastomeric material, a composition is prepared consisting of 0.50 g of polydimethylsiloxane with hydroxyl groups, 0.17 g of a metallosiloxane of the formula Fe[OSi(C ₆ H ₅ )(OC ₂ H ₅ ) ₂ ] ₃ and 0.33 g of hyperbranched polyethoxysiloxane, in toluene, and cure it in the same way as described in example 2.

Example 5

[037] To obtain 1.0 g of an elastomeric material, a composition is prepared consisting of 0.60 g of polydimethylsiloxane with hydroxyl groups, 0.20 g of a metallosiloxane of the formula [C₂H_fiveO]₃Zr[OSi(C₆H_five)(OC₂H_five)₂] and 0.20 g of hyperbranched polyethoxysiloxane, and it is cured in the same way as described in example 2.

Example 6

[038] To obtain 1.0 g of an elastomeric material, a composition is prepared consisting of 0.50 g of polydimethylsiloxane with hydroxyl groups, 0.17 g of a metallosiloxane of the formula [C₂H_fiveO]₃Zr[OSi(C₆H_five)(OC₂H_five)₂] and 0.33 g of hyperbranched polyethoxysiloxane, and it is cured in the same way as described in example 2.

Example 7

[039] To obtain 1.0 g of an elastomeric material, a composition is prepared consisting of 0.43 g of polydimethylsiloxane with hydroxyl groups, 0.14 g of a metallosiloxane of the formula [C₂H_fiveO]₃Zr[OSi(C₆H_five)(OC₂H_five)₂] and 0.29 g of hyperbranched polyethoxysiloxane, and it is cured in the same way as described in example 2.

Example 8

[040] To obtain 1.0 g of an elastomeric material, a composition is prepared consisting of 0.42 g of polydiethylsiloxane with hydroxyl groups, 0.01 g of a metallosiloxane of the formula [FROM₂H_fiveO]₂[OSi((CH₂)₃OCO)CH₂=C(CH₃))(OCH₃)₂] and 0.56 g of hyperbranched polyethoxysiloxane, in hexane and cure it in the same way as described in example 2.

Example 9

, 0,1г металлосилоксана формулы Zr[OSi(CН=СН₂)(OC₂H₅)₂]₄ и 0,2 г сверхразветвленного полиэтоксисилоксана, в смеси бензола и толуола (равные части) и проводят ее отверждение аналогично описанному в примере 2. [041] To obtain 1.0 g of an elastomeric material, a composition is prepared consisting of 0.6 g of polymethylvinylsiloxane with 3-aminopropyltriethoxysilyl groups, 0.1 g of a thioether-containing metallosiloxane of the formula

, 0.1 g of a metallosiloxane of the formula Zr[OSi(CH=CH ₂ )(OC ₂ H ₅ ) ₂ ] ₄ and 0.2 g of hyperbranched polyethoxysiloxane, in a mixture of benzene and toluene (equal parts) and it is cured similarly to that described in example 2 .

Example 10

[042] To obtain 1.0 g of an elastomeric material, a composition is prepared consisting of 0.6 g of polydimethylsiloxane with hydroxyl groups, 0.2 g of a metallosiloxane of the formula Zr[OSi(CH=CH ₂ )(OC ₂ H ₅ ) ₂ ] ₄ and 0.2 g of hyperbranched polyethoxysiloxane, in toluene, and cure it in the same way as described in example 2.

Example 11.

[043] To obtain 1.0 g of an elastomeric material, a composition is prepared consisting of 0.33 g of polydiethylsiloxane with hydroxyl groups, 0.17 g of polydiethylsiloxane with terminal 3-aminopropyldiethoxysilyl groups, 0.17 g of a metallosiloxane of the formula [CH ₃ O]Zn[ OSi ((CH ₂ ) ₃ SH) (OC ₂ H ₅ ) ₂ ] and 0.33 g of ethyl silicate-40, in pentane and cure it in the same way as described in example 2.

Example 12.

[044] To obtain 1.0 g of an elastomeric material, a composition is prepared consisting of 0.5 g of polymethylphenylsiloxane with hydroxyl groups, 0.17 g of a metallosiloxane of the formula [C ₂ H ₅ O] ₃ Zr[OSi(C ₆ H ₅ )(OC ₂ H ₅ ) ₂ ] and 0.33 g of ethyl silicate-40, in toluene, and it is cured in the same way as described in example 2.

[045] Characteristics of samples of elastomeric material obtained in examples 1-12, are shown in Table No. 1.

[046] Polydiorganosiloxanes pre-modified with 3-aminopropyldiethoxysilyl groups are obtained according to a known method by the interaction of rubber with terminal hydroxyl groups and 3-aminopropyltriethoxysilane according to a known method [RU 2669560C1, publication date 12.10.2018].

[047] The ethoxysiloxane used in the composition as a silica filler precursor is an oligo- and polyethoxysiloxane of a hyperbranched and linear structure.

[048] Hyperbranched polyethoxysiloxanes are obtained according to a known method [Kazakova, V. V., Rebrov, E. A., Myakushev, V. B., Strelkova, T. V., Ozerin, A. N., Ozerina, L. A., ... & Muzafarov, A. M. (2000). From a hyperbranched polyethoxysiloxane towards molecular forms of silica: a polymer-based approach to the monitoring of silica properties].

[049] Commercially available ethyl silicate-40 is used as the linear ethoxysiloxane. The use of such a filling option for elastomeric compositions, called "liquid filling" [Sun, C. C., & Mark, J. E. (1989). Comparisons among the reinforcing effects provided by various silica-based fillers in a siloxane elastomer. Polymer, 30(1), 104-106], when the formation of the filler occurs during the curing of the composition, greatly simplifies the process of obtaining elastomeric vulcanizates due to the possibility of mixing the components of the compositions in liquid form and makes it possible to obtain uniform transparent films with a uniformly distributed filler.

[050] A study of the dielectric characteristics showed that an increase in the dielectric constant of the resulting elastomeric materials is observed only in the presence of ethoxysiloxanes. As an example, in FIG. 1 shows the dependence of the dielectric constant of the claimed elastomeric materials on the frequency for the sample obtained in example 10, containing 1 wt.h. hyperbranched polyethoxysiloxane with respect to 3 wt. including polydimethylsiloxane, and a comparative sample obtained in example 1, without it.

[051] The preference for choosing zirconium in metallosiloxanes is determined by the fact that in this case a greater increase in the value of the dielectric constant is achieved.

[052] For example, when using titanium siloxane [C ₃ H ₇ O] ₃ Ti[OSi(CH=CH ₂ )(OC ₂ H ₅ ) ₂ ] or iron siloxane Fe[OSi(C ₆ H ₅ )(OC ₂ H ₅ ) ₂ ] ₃ the resulting materials are characterized at a frequency of 10 Hz by dielectric constant values of 3.1 and 4.3, respectively (examples 3 and 4, table No. 1), while with the introduction of zirconium siloxane [C ₂ H ₅ O] ₃ Zr[OSi(C ₆ H ₅ )(OC ₂ H ₅ ) ₂ ] (example 6, table No. 1) other things being equal relative to the composition of the composition, the dielectric constant is 28.2 at 10 Hz.

[053] In this case, an effective way to control the dielectric properties of elastomers is to change the ratio of polydimethylsiloxane(s) and ethoxysiloxane from 3:1 to 3:4 wt. hours, respectively. Thus, the permittivity at 10 Hz of an elastomeric composition based on a functional metallosiloxane of the formula [C ₂ H ₅ O] ₃ Zr[OSi(C ₆ H ₅ )(OC ₂ H ₅ ) ₂ ] increases from 3.2 to 28.2 with increasing the amount of hyperbranched polyethoxysiloxane from 1 to 2 wt.h. 3 wt.h. polydimethylsiloxane (examples 5 and 6, respectively, table No. 1). The increase in the amount of zirconium siloxane from 1 to 2 wt.h. in relation to 3 wt. including polydimethylsiloxane leads to a decrease in the dielectric constant from 28.2 to 13.2 (examples 6 and 7, respectively, table No. 1).

[054] The elastomeric material obtained by the claimed method has an increased dielectric constant, which in particular can vary from 3 to 100 (at 10 Hz). The study of the dielectric characteristics showed that an increase in the dielectric constant of the resulting elastomeric materials is observed only in the presence of ethoxysiloxanes.

Sensor based on dielectric elastomer material.

[055] Dielectric elastomeric material obtained in example 6, 40 μm thick with electrodes deposited on 2 sides, and insulating layers based on polydimethylsiloxane.

Actuator based on dielectric elastomer material.

[056] The 17% pre-stretched dielectric elastomer material prepared in Example 6, 40 µm thick, coated with applied circular electrodes, is fixed between two Plexiglas rings with an inner diameter of 50 mm and an outer diameter of 70 mm.

Table 1 Characteristics of samples of elastomeric material obtained according to examples 1-12

No. p / p Formula of metallosiloxane(s) (MS) ^R1 , ^R2 Ethoxysiloxane The composition of the compositions, wt.h. The dielectric constant/
frequency Hz Ultimate tensile strain, % MS EAP ¹ /
PDOS ^2** Ethoxysiloxane one* Zr[OSi(CH=CH ₂ )(OC ₂ H ₅ ) ₂ ] _{4 CH3} / _CH3 - one 3/0 - 2.5/10 271 2 [C ₂ H ₅ O] ₂ Zr[OSi(C ₆ H ₅ )(OC ₂ H ₅ ) ₂ ] _{2 CH3} / _CH3 SR PEOS ^*** 0.2 3/0 3 5.4/10 189 3 [С ₃ H ₇ O] ₃ Ti [OSi (CH \u003d CH ₂ ) (OC ₂ H ₅ ) ₂ ] _CH3 / _CH3 SR PEOS one 3/0 2 3.1/10 91 4 Fe[OSi(C ₆ H ₅ )(OC ₂ H ₅ ) ₂ ] _{3 CH3} / _CH3 SR PEOS one 3/0 2 4.3/10 21 five [C ₂ H ₅ O] ₃ Zr[OSi(C ₆ H ₅ )(OC ₂ H ₅ ) ₂ ] _CH3 / _CH3 SR PEOS one 3/0 one 3.2/10 215 6 [C ₂ H ₅ O] ₃ Zr[OSi(C ₆ H ₅ )(OC ₂ H ₅ ) ₂ ] _CH3 / _CH3 SR PEOS one 3/0 2 28.2/10 16 7 [C ₂ H ₅ O] ₃ Zr[OSi(C ₆ H ₅ )(OC ₂ H ₅ ) ₂ ] _CH3 / _CH3 SR PEOS 2 3/0 2 13.2/10 3 8 [С ₂ H ₅ O] ₂ [OSi((CH ₂ ) ₃ OCO)CH ₂ =C(CH ₃ ))(OCH ₃ ) ₂ ] _{C2H5 / C2H5 _} SR PEOS 0.1 3/0 4 99.7/10 10 nine

и Zr[OSi(CН=СН₂)(OC₂H₅)₂]₄

and Zr[OSi(CH=CH ₂ )(OC ₂ H ₅ ) ₂ ] ₄ CH ₃ /
CH ₂ \u003d CH SR PEOS 0.5/0.5 0/3 one 4.2/10 120 10 Zr[OSi(CH=CH ₂ )(OC ₂ H ₅ ) ₂ ] _{4 CH3} / _CH3 SR PEOS one 3/0 one 4.4/10 19 eleven [СH ₃ O]Zn[OSi((CH ₂ ) ₃ SH)(OC ₂ H ₅ ) ₂ ] _{C2H5 / C2H5 _} Ethyl silicate - 40 one 2/1 2 6.5/10 90 12 [C ₂ H ₅ O] ₃ Zr[OSi(C ₆ H ₅ )(OC ₂ H ₅ ) ₂ ] CH ₃ /C ₆ H ₅ Ethyl silicate - 40 one 3/0 2 7.0/10 80

^* Comparison example

^** PDOS ¹ and PDOS ² denote polydiorganosiloxane with terminal hydroxyl and 3-aminopropylsilyl groups, respectively.

^*** CP PEOS stands for hyperbranched polyethoxysiloxane

Claims (32)

1. Polysiloxane composition for obtaining elastomeric materials, including: - polydiorganosiloxane with terminal hydroxyl groups and / or its analogue with terminal 3-aminopropyldiethoxysilyl groups of the general formula:

, where X is a hydrogen atom, -Si(OC ₂ H ₅ ) ₂ (CH ₃ ) ₂ NH ₂ , R ¹ means CH ₃ -, C ₂ H ₅ - or C ₆ H ₅ -, R ² means CH ₃ -CH ₂ =CH- or C ₂ H ₅ -, - one or more functional metallosiloxanes of the general formula:

, where M is a two-, three- or four-valent metal selected from Zn, Zr, Ti and Fe (III), p+m corresponds to the valency of the metal provided that p≠m, where m is 1, 2, 3 or 4, R and Alk, independently of each other, are C ₁ -C ₄ - alkyls, R' is C ₆ H ₅ -, CH ₂ =CH-, SH(CH ₂ ) ₃ -, CH ₂ =CHC(O)O(CH ₂ ) ₃ -, CH ₂ =C(CH ₃ )C(O )O(CH ₂ ) ₃ -,

or

, - ethoxysiloxane, moreover, the mass ratio of polydiorganosiloxane(s) and functional(s) metallosiloxanes is from 3:0.1 to 3:2, and polydiorganosiloxane(s) and ethoxysiloxane is from 3:1 to 3:4 wt.h. respectively. 2. The polysiloxane composition of claim 1 wherein M is zirconium or titanium, most preferably zirconium. 3. A method for producing an elastomeric material, including the following steps: a) preparing a polysiloxane composition according to claim 1 by mixing polydiorganosiloxane(s) with metallosiloxane and ethoxysiloxane; b) mixing with the solvent obtained in stage a) polysiloxane composition with the formation of a solution of the polysiloxane composition; c) drying the solution of the polysiloxane composition formed in step b) to visually detectable signs of curing; d) heating the dried solution of the polysiloxane composition formed in step c), where heating is carried out sequentially for 1 hour at a temperature of 50°C, 1 hour at a temperature of 70°C, 1 hour at a temperature of 100°C and then for 2 hours at temperature of 150°C to obtain an elastomeric material. 4. The method of obtaining according to p. 3, in which a non-polar solvent is used as a solvent. 5. The preparation method according to claim 4, wherein toluene, pentane, cyclopentane, hexane, benzene, cyclohexane, methylcyclohexane, heptane, xylene, or mixtures thereof are used as the non-polar solvent. 6. The production method according to claim 3, wherein the drying was carried out at atmospheric pressure. 7. The production method according to claim 3, wherein the drying is carried out under reduced pressure. 8. Elastomeric material obtained according to paragraphs. 3-7, having a dielectric constant of more than 3 (10 Hz). 9. The use of an elastomeric material according to claim 8 in electromechanical devices. 10. The use of an elastomeric material according to claim 9 in electromechanical devices with coated electrodes. 11. The use of an elastomeric material according to claim 10 in electromechanical devices that are sensors and / or actuators. 12. Method for regulating the dielectric properties of the elastomeric material obtained according to paragraphs. 3-7 by changing the concentration ratio of polydiorganosiloxane(s) and ethoxysiloxane. 13. A method for controlling the dielectric properties of the elastomeric material obtained according to claim 12 by changing the concentration ratio of polydiorganosiloxane(s) and ethoxysiloxane from 3:1 to 3:4 wt.h. respectively.

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