MXPA01000118A

MXPA01000118A - Hydrophobicity imparting particulate

Info

Publication number: MXPA01000118A
Application number: MXPA/A/2001/000118A
Authority: MX
Inventors: Amarasekera Jayantha; Raymond Krahn John
Original assignee: General Electric Company
Priority date: 1999-12-27
Filing date: 2001-01-08
Publication date: 2002-06-05

Abstract

A silicone composition comprises (A) a silicone polymer and (B) a hydrophobicity imparting particulate filler that imparts a hydrophobicity property to the composition. An insulator comprises a housing portion that includes a cured product of (A) a silicone polymer and (B) an hydrophobicity imparting particulate filler. A hydrophobicity recovery property of a silicone polymer composition can be improved by determining a target hydrophobicity recovery property for the cured silicone composition, selecting an hydrophobicity imparting particulate filler to impart the hydrophobicity recovery property to the silicone polymer composition and compounding a blend of (A) a silicone polymer and (B) the selected filler and heating to cure the blend.

Description

MATERIAL IN THE FORM OF PARTICLES IMPARTIDOR OF HYPOPHOBIC CHARACTER BACKGROUND OF THE INVENTION The invention relates to silicone rubber compositions. In particular, this invention relates to silicone rubber compositions useful as high voltage insulators (AAV). High-voltage insulators, such as those used in power transmission lines, distribution stations or surge suppressors, are typically made of porcelain or glass. In ordinary working conditions, these high-work insulators withstand prolonged use. A severe polluted environment, such as a coastline or an industrial district, can cause the insulation to degrade. The high electrical stress can cause droplets of water to join together in a single larger drop known as a filament. The water filaments dissolve the conductive contamination to form conductive paths that decrease the surface resistance. As conductive paths are formed along the surface of an insulator, ohmic heating, caused by the leakage current, causes a decrease in resistance and a corresponding increase in current. The heating may cause evaporation and subsequent drying to form a "dry band". The electrical effort through this "band" or interstice can be the site for electric shock activity (corona effect, arcing and / or partial discharges). The download activity leads to contomeamiento. "Hydrophobic character" as used herein refers to a lack of affinity or a repulsion to water or to stop adsorbing water. A hydrophobic surface has low surface energy. The water remains on the surface as separate droplets. In contrast, a hydrophilic surface (which sticks to water) has high free surface energy, thus making it possible to cover the surface like a film. Moisture periods in a polluted environment can cause electric shock activity on the surface of an insulator that destroys the hydrophobic character. If the property of hydrophobic character is not recovered, more water accumulates, accelerating the formation of arcs and the activity of discharges in the dry bands. It can determine the hydrophobic character by measuring a contact angle (AC) between a substrate surface and a pure water surface. Silicones without additives typically have a contact angle of about 114 °. After corona treatment to destroy the hydrophobic character, the contact angle is typically in a range of between about 10 ° and about 50 °. The recovery of the hydrophobic character is measured after a period of rest of 24 hours. The contact angle recovered (ACR) is conventionally the contact angle after the period subsequent to corona treatment. Both the hydrophobic character and the contact angle are important properties in high voltage insulators, particularly when used in harsh environments. Thus, there is a need for silicone compositions with improved hydrophobic properties.

BRIEF DESCRIPTION OF THE INVENTION The present invention relates to a particulate material that imparts an improved hydrophobic character and improved contact angle property recovered to a silicone composition. The silicone composition comprises (A) a silicone polymer and (B) a hydrophobic imparting inorganic particulate material (MPICH) that imparts improved hydrophobic properties. In another aspect, the present invention relates to a silicone composition, comprising (a) a silicone polymer in a range of between about 15% and about 50%, by weight of the total composition; (b) a hydrophobic imparting particulate material in a range of about 1% and about 50% by weight of the total composition imparting a hydrophobic property to the total composition; (c) an agent against surface discharges and a flame retardant in a range of between about 20% and about 70% by weight of the total composition; (d) a coupling agent in a range of between about 0.001% and about 1% by weight of the total composition; (e) a curing agent in a range between about 0.1% and about 5% by weight of the total composition; (f) an extender filler up to about 20% by weight of the total composition; and (g) at least one processing fluid in a range of between about 0.1% and about 5% by weight of the total composition. In another aspect, the present invention relates to a silicone composition comprising (A) a silicone polymer and (B) two or more materials in the form of imparting particles of hydrophobic character imparting a property of a hydrophobic character to the composition or at least one imparting particulate material of a hydrophobic character imparting a hydrophobic property to the composition and a filler. In another aspect, the present invention relates to an insulator comprising a housing portion. The housing portion comprises a cured product of (A) a silicone polymer and (B) a hydrophobic imparting particulate material. In still another aspect, the present invention relates to an insulator comprising a housing portion comprising a cured product of (A) a silicone polymer and (B) two or more materials in the form of hydrophobic characterizing particles that impart a property of hydrophobic character to the composition or an inorganic imparting material of a hydrophobic character that imparts a hydrophobic property to the composition and a filler. The present invention also relates to a method of imparting a recovery property of the hydrophobic character to a silicone polymer composition. In the method, a predicted recovery property of hydrophobic character is determined for a silicone polymer composition. A hydrophobic imparting inorganic particulate material is selected to impart a hydrophobic character recovery property to a silicone polymer composition. The inorganic particulate material of hydrophobic character is then added to the silicone polymer composition in an amount to impart the recovery property of the hydrophobic character. In another aspect, the present invention relates to a method of improving the hydrophobic property of a cured composition of silicone polymer. In the method, an expected property of hydrophobic character is determined for a cured composition of silicone polymer. A hydrophobic imparting inorganic particulate material is selected that imparts a hydrophobic property to a silicone polymer composition. The mixture is then stirred and a mixture of (A) a silicone polymer and (B) the selected inorganic filler is cured.

BRIEF DESCRIPTION OF THE DRAWING Figure 1 is a statistical representation of the contact angles for a set of conventional improvers of the recovery of the hydrophobic character and the material in the form of imparting particles of hydrophobic character according to the invention.

DETAILED DESCRIPTION OF THE INVENTION It has been found that the addition of an inorganic particulate material improves the hydrophobic character of the silicone compositions when at least one portion of the inorganic filler is replaced by an inorganic particulate material. The improved hydrophobic character includes both the initial contact angle and the recovered contact angle. The silicone compositions of the present invention can be prepared by stirring silicone polymer with a hydrophobic character-imparting particulate material that has been selected to impart the recovery property of the hydrophobic character. "hydrophobic character imparting particulate material" as used herein refers to an inorganic material that substantially improves the hydrophobic properties of a silicone polymer as and / or substantially improves the contact angle recovered from composition.

The hydrophobic imparting particulate material may be a silicate or a carbonate. Suitable silicates include layered silicate minerals and three-dimensional silicates. Examples of layered silicates include clay minerals such as kaolinite, halloysite, montmorillonite (bentonite or fuller's earth), vermiculite, nontronite, hectorite, laponite, saponite and beidelite; micas such as muscovite, phlogopite, biotite; friable micas such as daisies, clintonitas; serpentines such as antigorite and chrysotile-steatite; and other silicates such as cristolite, talc and pyrophilite. Materials in the form of hydrophobic imparting particles include three-dimensional silicates such as feldspars, zeolites, groceries and mixtures thereof. Examples of feldspars include orthoclase, albite and anorthite. Examples of suitable mixtures of these three-dimensional silicates include mixtures of orthoclase and albite or mixtures of different proportions which are referred to as alkali feldspars. Such alkali feldspars include sanidin and anorthoslase. The mixtures of albite and anortite are suitable. These mixtures are called plagioclase feldspars and include oligoclase, andesine, lactorite and bitonite. Examples of zeolite include faujasite, analcita, chabasite, heulandite, stilbite and natrolite. Examples of groceries include sodalite, noselite and ultramarine. The carbonates used in the present invention include calcite (calcium carbonate), magnesite (calcium carbonate), siderite, iron carbonate, rhodochrosite (magnesium carbonate), smithsonite, (zinc carbonate), zinc carbonate and strontium carbonate. . The materials in the form of imparting particles of hydrophobic character also include mixtures of carbonates and silicates, for example a mixture of calcium carbonate and magnesium carbonate and a mixture of magnesium silicate and calcium carbonate. In one embodiment of the present invention, the inorganic imparting material of hydrophobic nature excludes calcium carbonate, silica, ground quartz, magnesium silicate and magnesium aluminum silicate. The hydrophobic imparting particulate material is typically present in an amount in a range of from about 1% by weight to about 50% by weight of the total composition. More typically, the hydrophobic imparting particulate material is present in an amount in a range of between about 5% by weight and about 25% by weight and very typically is present in a range of between about 12% by weight and about 18% by weight of the total composition. The hydrophobic particle-like material in finely ground or particulate form is commonly used. The material in the form of hydrophobic character imparting particles can be used as provided andWhen the hydrophobic imparting particulate material includes surface silanol groups or the like, it can be treated on its surface with a treatment agent such as a silane coupling agent. The treatment agent enhances the interaction of the material in the form of hydrophobic particles with the polysiloxane, thus enhancing the dispersible and hydrophobic character. The treating agent may also be chosen to provide hydrophobic groups on the mineral surface to facilitate the interaction of the material in the form of polymer particles and to impart improved mechanical properties to the final polymer product. An organosilane coupling agent, when used as a treatment agent for the hydrophobic imparting particulate material, can act as a surface modifier for the high voltage insulator and as an interlayer for the coupling between the particulate material hydrophobic character and the siloxane polymer. A repeating unit of formula I represents the silicone polymer used in the compositions of the present invention: R1 R1 R > 3-O4 SSiÍ-O4-S > i-0-R3 R2 R wherein R1 independently in each occurrence represents C-j alkyl. 4 or C2-4 alkylene; R 2 independently in each occurrence represents C 1-4 alkyl, C 1 haloalkyl or C 4 alkylene; R3 independently of each occurrence represents H, alkyl of C-MO, alkylene of C2-4, cycloalkyl of C-6, OH or halogenalkyl of C-; and n represents an integer from 1, 000 to 20,000. Another preferred composition comprises a silicone polymer wherein, R1 independently in each occurrence represents CH3 or CH = CH2; R2 independently of each occurrence represents CH3, CH2CH2CF30 CH = CH2; R3 independently of each occurrence represents CH3, CH = CH2, OH or CH2CH2CF3; and n represents an integer from about 4,000 to about 10,000. Still another embodiment of the invention provides a composition that includes a silicone polymer, a hydrophobic imparting particulate material, a coupling agent, and a reinforcing filler. The hydrophobic imparting particulate material is bentonite and the reinforcing filler is fumed silica, precipitated silica or carbon black having a surface area in a range of about 50 m2 / g to about 400 m2 / g. Examples of coupling agents include vinyltriethoxysilane (VTES), vinyltrimethoxysilane and methacrylpropyltrimethoxysilane. Another embodiment of the present invention includes a silicone polymer, a particulate-imparting material of a hydrophobic nature and a component against surface carbonization and flame retardant. The silicone polymer is present in an amount in a range of between about 25% and about 40% by weight of the total composition. The hydrophobic particle-shaped particulate material is present in an amount ranging from 1% to about 50% by weight of the total composition. A component against surface carbonization and flame retardant is present in an amount in a range of between 25% and approximately 60% by weight of the total composition. A "component against surface carbonization and flame retardant" as used herein refers to a component that has the ability to improve the resistance to arcs and flame retardancy. Another embodiment of the present invention may include a silicone polymer, a hydrophobic imparting particle-shaped material, an anti-surface char agent and a flame retardant, a coupling agent, a curing agent, an extender filler and a fluid of processing. "Against surface carbonization" as used herein refers to a material that acts as a surface modifier for fumed silica and alumina trihydrate and as an interlayer for the coupling between fumed silica and alumina trihydrate with siloxane polymer. "Curing agent" as used herein refers to a chemical substance that has the ability to harden the silicone composition. "Extender filler" as used herein refers to materials that improve the strength of the silicone polymer. "Processing fluid" as used herein refers to a fluid that is typically added during the stirring process to facilitate the mixing of the polymers with the fillers.

Alumina trihydrate, also commonly known as aluminum hydroxide, improves the resistance to arcs and the flame retardancy of silicones. Alumina trihydrate is a compound represented by the chemical formula AI203-3H20 or AI (OH) 3. Alumina trihydrate with a particle size of less than about 10 microns is preferred, if the combined amount of alumina trihydrate is too small, the resistance to the arcs is lost: if the combined amount is too large, it is adversely affected the processing capacity. The amount of alumina trihydrate is preferably in the range of between about 15 parts by weight and about 300 parts by weight of 100 parts of the diorganosiloxane polymer or mixture of polymers and more preferably in the range of between about 50 parts and about 200 parts by weight. Weight per 100 parts of polymer. Smoke silica fine powder can be added as an extender filler to the compositions of the present invention. Preferred is fumed silica having an average particle size less than or equal to about 50 microns and a specific surface area greater than about 100 m2 / g. A smaller average particle size is preferred, since it gives a larger surface area, resulting in better reinforcement properties. In addition, the silica treated on its surface, for example the hydrophobic silica treated on its surface with organosiloxane (s), hexaorganodisilazane or diorganociclopolisiloxane further enhance the reinforcing properties of the filler. If the amount of fumed silica used in these formulations is too small, the mechanical strength of the silicone polymer will deteriorate, while if it is too large, it prevents the effective use of a higher proportion of alumina trihydrate. The amount of fumed silica is generally in the range of between about 10 parts by weight and about 100 parts by weight, preferably in the range of between about parts by weight and about 80 parts by weight, based on 100 parts of polymer of silicone. Other examples of extender filler include ground quartz, calcium carbonate, magnesium silicate or magnesium aluminum silicate. Another type of filler, a non-reinforcing filler, can be used in the compositions of the present invention. This filler facilitates good mixing of fumed silica and alumina trihydrate with polyorganosiloxane polymers and provides compositions with well-dispersed filler content. An example of a non-reinforcing filler is electrically conductive non-conductive quartz. Quartz also has good thermal conductivity properties and provides good heat transfer during molding. An organosilane coupling agent can be used in the silicone composition. The coupling agent makes the hydrophobic alumina trihydrate and the fumed silica hydrophobic and interacts with the diorganosiloxane polymer to enhance the dispersible capacity and reinforcing effect of the alumina trihydrate and the fumed silica. The silicone composition incorporating an organosilane coupling agent typically has dielectric strength greater than about 300 volts / 25.4 microns (vpm), surface carbonization strength greater than about 100 minutes, as measured by test procedure number D2303 of the method American regulatory test (ASTM), and surface carbonization resistance greater than about 3 kilovolts (kV), as measured by procedure 587 of the International Electromechanical Commission (IEC). Preferred coupling agents are represented by structures represented by formulas (II) to (V): (II) R4R5Si (OR5) 2; (III) R1Si (OR2) 3; (IV) R R 5 Si (OOCR 5) 2; or (V) R4Si (OOCR5); wherein R 4 and R 5 independently in each occurrence represent C 1 - β alkyl groups, phenyl groups and C 2-6 alkenyl groups - Preferably, the curing agent is peroxide based. Organic peroxide or a combination of peroxides can be used to cure the compositions of the invention to provide rubber-like elastomeric high-voltage insulating parts. Examples include diacylperoxides, ketonperoxides, peroxyesters, dialkylperoxides, peroxyketals, peroxycarbonates and tertiary alkylhydroperoxides. Other optional additives used in the compositions of the present invention include coloring agents, mold release agents and heat resistance agents. Examples of coloring agents and pigments include carbon black, red or black iron oxide and Ti 2, which provide specific colors to the insulators. Examples of mold release include silicone fluids or metal stearates, such as magnesium stearate, calcium stearate or aluminum stearate. Examples of heat resistance agents include cerium octoate, cerium hydroxide, magnesium oxide, cerium oxide and magnesium hydroxide. The processing fluid can be polydimethylsiloxane terminated with methyl or hydroxy. Examples of processing fluid include alkylpolysiloxane oil or phenylpolysiloxane oil which is blocked with hydroxyl, allyl or phenyl groups at both terminal ends of the molecular chain. The silicone polymer is present in a range of between about 15% by weight and about 50% by weight of the total composition. The hydrophobic imparting particulate material selected to impart hydrophobic character recovery property is present in a range of from about 1% by weight to about 50% by weight of the total composition. The agent against surface carbonization is present in a range of between about 20% by weight and about 70% by weight of the total composition. The coupling agent is present in a range of between about 0.001% by weight and about 1% by weight of the total composition. The curing agent is present in a range of between about 0.1% by weight and about 5% by weight of the total composition. The extender filler is present up to about 20% by weight of the total composition. The processing fluid is present in a range of between about 0.1% by weight and about 5% by weight of the total composition. High voltage insulating compositions are typically prepared by mixing silicone and the selected inorganic filler to improve the hydrophobic character in the presence of fluids and silane coupling agents. The silicone compositions optionally contain a mold release agent and a heat resistance agent. The silicone compositions can be cured at elevated temperatures and can be converted to insulators in different ways either by compression, injection or transfer molding processes. The silicone gum, the liquid additives and the pigments were changed to a kneader such as a Banbury mixer and mixed for several seconds. Inorganic fillers are typically added in small portions during mixing to obtain a homogeneous product. The product is then unloaded and milled on a two-roll mill and filtered by extrusion through a 150 mesh screen. The hydrophobic character of a silicone polymer surface and the time to recover the hydrophobic character after the hydrophobic character are measured. that was treated with corona effect. In order to measure the hydrophobic character and the recovery of the hydrophobic character, cured silicon sheets are prepared (15.24 cm x 15.24 cm x 0.19 cm in size). The change of the contact angle with the water is measured with a leaf, before and after submitting the leaf to corona treatment. An initial contact angle of a water droplet of 1 microliter is measured with a goniometer. It is applied with a corona shock discharge of 40 strokes in an interstice of 381 micras to destroy the hydrophobic character. The recovery is measured, monitoring the contact angle of the water droplets of 1 microliter until there is no change in the contact angle. A period of several days typically passes until there is no change. This angle determined after this period is called the recovered contact angle (ACR). The contact angle and the recovered contact angle are measured using a Video Contact Angle System 2000 instrument, manufactured by Advanced Surface Technology, Inc. A drop of 1 microliter of distilled water is automatically supplied onto the surface of the specimen and a amplified digital image of the drop. The contact angle of an enlarged image is then measured on the screen, using Advanced Surface Technology software. Very specifically, the silicone composition used in the invention is used as an insulator. The insulator comprises a housing portion and includes a cured product of a silicone polymer and a hydrophobic imparting particulate material imparting a property of a hydrophobic character to the cured product. The hydrophobic imparting particulate material typically excludes calcium carbonate, silica, ground quartz, magnesium silicate and magnesium aluminum silicate. In another embodiment, the accommodation portion of the housing includes a cured product of a silicone polymer and two or more materials in the form of hydrophobic characterizing particles. In order that those skilled in the art may better practice the invention, the following examples are given by way of illustration and not by way of limitation.

EXAMPLES In these examples, silicone heat cured rubber products were formulated that were suitable for molding type applications in the production of high voltage (AV) insulators. A diorganopolysiloxane gum (40 parts) having a viscosity in the range of between about 20 million centipoise and about 30 million centipoise was fed, which consisted of 99.77 mol% of dimethylsiloxane units and 0.23% of methyl vinyl siloxane units, a diorganopolysiloxane gum (60 parts) having a viscosity in a range between about 30 million centipoise and about 120 million centipoise and consisting of 99.02% mol of dimethylsiloxane units and 0.08% of methylvinylsiloxane units, dimethylsiloxane oligomer blocked at their ends with silanol groups (60 parts) having viscosity of 30 centipoise, vinyltriethoxysilane (VTES) (0.5 parts), 9 fumed silica treated with dimethyltetracyclosiloxane (35 parts) having a specific surface area of 200 m2 / g, alumina trihydrate (ATH) (120 parts) having a mean particle diameter of 1 miera and ACR filler (35 parts) , to a kneading mixer (Banbury mixer) and kneaded to form a homogeneous mixture at room temperature. The mixture was added with aluminum stearate (0.3 parts), basic color mixture based on black silicone rubber (50% carbon black) (0.88 parts) and 2,5-dimethyl (t-butylperoxy) hexane peroxide. (1.25 parts) and mixed with a kneader to obtain a homogeneous product. The product was compression molded at 177 ° C for 15 minutes. The formulation process was repeated with several materials to determine its effect on the recovery of the hydrophobic character. The materials used were Minusil (ground quartz), talc (hydrated magnesium silicate), talc treated with silane (Mistron 604 AV, Mistron CB from Luzenac America Inc.), bentonite clay, feldspar and calcium carbonate. Minusil comparison of ten (10) micras was used. Additionally, formulations were prepared with silicone fluids blocked with methoxy that improve the hydrophobic character and compared with the formulations containing filler. Formulations blocked with methoxy were prepared with 1% fluid discharges and 0.5% fluid discharges. Figure 1 shows a statistical representation of the contact angles for a set of compositions that include components that improve the hydrophobic character. The following table identifies the component of the compositions represented in figure 1.

PICTURE Formulation ACR code letter Bentonite A 112 Talc B 106 Talc treated with silane C 108 Blocked siloxane fluid with 1% methoxy D 95 Siloxane fluid blocked with 0.5% methoxy E 89 unusable F 85 Feldspar G 92 Calcium carbonate H 101 All the contact angles were for the recovery of the hydrophobic character. The hydrophobic nature of the surface was first destroyed (40 strokes of a crown-effect rod, sustained at 381 microns on the surface, using a Tantee HV 05-2 corona generator set at 85% of its total power) . The corona treatment imitates the activity of electric discharges on an insulating surface outdoors that destroys the hydrophobic character. The samples were then allowed to "recover" the hydrophobic character in 24 hours. Figure 1 represents the contact angle recovered. The example shows that the materials in the form of hydrophobic imparting particles of the present invention can impart more than 95% of the recovered contact angle. The addition of hydrophobic imparting particulate material material significantly improved the contact angle recovered and the improvements were better than those obtained when using improvers such as methoxy blocked siloxane fluids. See Figure 1, D and E. Although modalities of the invention have been described, the present invention is susceptible to variations and modifications, and should therefore not be limited to the precise details of the examples. The present invention includes changes alterations that fall within the scope of the following claims.

Claims

NOVELTY OF THE INVENTION CLAIMS 1. - A silicone composition, comprising (A) a silicone polymer and (B) a hydrophobic imparting particulate material imparting a hydrophobic property to said composition.
2. The composition according to claim 1, further characterized in that said silicone is a diorganopolysiloxane.
3. The composition according to claim 1, comprising the material in the form of imparting particles of hydrophobic character in a range between about 1% and about 50% by weight of the total composition.
4. The composition according to claim 1, comprising the material in the form of imparting particles of hydrophobic character in a range between about 5% and about 25% by weight of the total composition.
5. The composition according to claim 1, comprising the hydrophobic imparting particulate material in a range between about 12% and about 18% by weight of the total composition. 6. - The composition according to claim 1, further characterized in that the hydrophobic imparting particulate material comprises a silicate or a carbon. 7. The composition according to claim 6, further characterized in that said silicate comprises kaolinite, halloysite, montmorillonite, vermiculite, nontronite, hectorite, laponite, saponite or beidelite 8. The composition according to claim 7, further characterized in that said montmorillonite comprises bentonite or fuller's earth. 9. The composition according to claim 6, further characterized in that said silicate comprises a friable mica or mica. 10. The composition according to claim 9, further characterized in that said mica comprises muscovite, phlogopite or biotite. 11. The composition according to claim 9, further characterized in that said friable mica comprises daisy and clintonite. 12. The composition according to claim 6, further characterized in that said silicate comprises a serpentine, cristolite, talc and pyrophyllite. 13. - The composition according to claim 6, further characterized in that said silicate comprises a feldspar, zeolite, ultramarine. 14. The composition according to claim 13, further characterized in that said feldspar comprises orthoclase, albite or anortite. 15. The composition according to claim 1, further characterized in that said material in the form of imparting particles of hydrophobic character comprises a mixture of materials in the form of imparting particles of hydrophobic character. 16. The composition according to claim 15, further characterized in that said hydrophobic imparting particulate material comprises a mixture of a feldspar, a zeolite or an ultramarine mineral. 17. The composition according to claim 15, further characterized in that said mixture comprises orthoclase and albite. 18. The composition according to claim 15, further characterized in that said mixture comprises an alkali feldspar. 19. The composition according to claim 15, further characterized in that said mixture comprises sanidina and anortoclase. 20. The composition according to claim 15, further characterized in that said mixture comprises albite and anorthite. 21. - The composition according to claim 15, further characterized in that said mixture comprises a plagioclase feldspar. 22. The composition according to claim 15, further characterized in that said mixture comprises oligoclase, andesine, latorite or bitonite. 23. The composition according to claim 1, further characterized in that said hydrophobic imparting particulate material comprises a zeolite selected from the group consisting of faujasite, analcita, chabasita, heulandita, estilbita and natrolita. 24. The composition according to claim 1, further characterized in that said material in the form of imparting particles of hydrophobic character comprises an ultramarine selected from the group consisting of sodalite, noselite and ultramarine. 25. The composition according to claim 1, further characterized in that said hydrophobic imparting particulate material comprises a carbonate. 26. The composition according to claim 25, further characterized in that said carbonate comprises magnesite (magnesium carbonate), siderite (iron carbonate), rhodochrosite (manganese carbonate), smithsonite (zinc carbonate), zinc carbonate or strontium carbonate. 27. - The composition according to claim 1, further characterized in that said hydrophobic imparting particulate material comprises bentonite. 28.- The composition according to claim 1, further characterized in that said material is treated in the form of hydrophobic characterizing particles, with a silane treatment agent. 29. The composition according to claim 1, further characterized in that said silicone polymer comprises a repeating unit of the formula I: wherein R1 independently at each occurrence represents C? _4 alkyl or C - alkylene; R 2 independently in each occurrence represents C 1 alkyl, C 1-4 haloalkyl or C 2-4 alkylene; R3 independently of each occurrence represents H, alkyl of C-MO, alkylene of C2-4, cycloalkyl of C4.6, halogenoalkyl of C-OH OH; and n represents an integer from 1, 000 to 20,000. 30. The composition according to claim 29, further characterized in that: R1 independently in each occurrence represents CH3 or CH = CH2; R2 independently of each occurrence represents CH3, CH2CH2CF30 CH = CH2; R3 independently of each occurrence represents CH3, CH = CH2, OH or CH2CH2CF3; and n represents an integer from about 4,000 to about 10,000. 31. The composition according to claim 29, further characterized in that the vinyl content of the silicone polymer is present in a range of between about 0.05% by weight and about 0.5% by weight of the total composition 32.- The composition according to claim 1, comprising: (a) a silicone polymer in a range of between about 15% and about 50%, by weight of the total composition; (b) a hydrophobic imparting particulate material in a range of about 1% and about 50% by weight of the total composition; (c) an agent against surface discharges and a flame retardant in a range of between about 25% and about 60% by weight of the total composition 33. The composition according to claim 1, further characterized in that the silicone composition it also comprises a reinforcing filler and a coupling agent. 34. The composition according to claim 33, further characterized in that the reinforcing filler is fumed silica, precipitated silica or carbon black having a surface area in a range of between 50 m2 / g and about 400 m2 / g. 35. The composition according to claim 33, further characterized in that the coupling agent comprises vinyltriethoxysilane (VTES) or vinyltrimethoxysilane, meta-acrylpropyltrimethoxysilane. 36. The composition according to claim 1, further characterized in that the silicone composition excludes calcium carbonate, silica, ground quartz, magnesium silicate and magnesium aluminum silicate. 37.- A composition comprising (a) a silicone polymer in a range of between about 15% and about 50%, by weight of the total composition; (b) a hydrophobic imparting particulate material in a range of about 1% and about 50% by weight of the total composition imparting a hydrophobic property to the total composition; (c) an agent against surface discharges and a flame retardant in a range of between about 20% and about 70% by weight of the total composition; (d) a coupling agent in a range of between about 0.001% and about 1% by weight of the total composition; (e) a curing agent in a range between about 0.1% and about 5% by weight of the total composition; (f) an extender filler up to about 20% by weight of the total composition; and (g) at least one processing fluid in a range of between about 0.1% and about 5% by weight of the total composition. 38. - The composition according to claim 37, further characterized in that the curing agent comprises a peroxide-based curing agent. 39.- The composition according to claim 37, further characterized in that said curing agent comprises a diacylperoxide, ketonperoxide and dialkyl peroxide. 40.- The composition according to claim 37, further characterized in that the extender filler comprises ground quartz, magnesium silicate or magnesium aluminum silicate. 41. The composition according to claim 37, further characterized in that the processing fluid comprises a polydimethylsiloxane terminated with methyl or hydroxy. 42. The composition according to claim 37, further comprising a mold release agent, a coloring agent, a heat resistance agent or combinations thereof. 43.- The composition according to claim 37, further characterized in that the mold release agent comprises a fluid of silicone, magnesium stearate, aluminum or cerium. 44. The composition according to claim 37, further characterized in that the heat resistance agent comprises a cerium octoate, cerium hydroxide, magnesium oxide, cerium oxide or magnesium hydroxide. 45. The composition according to claim 37, further characterized in that said hydrophobic imparting particulate material comprises bentonite. 46.- The composition according to claim 37, further characterized in that said silicone polymer comprises a repeating unit of the formula I: wherein R 1 independently in each occurrence represents C 1 -alkyl. 4 or C2-4 alkylene; R2 independently at each occurrence represents C? -4 alquilo alkyl, C halo halo haloalkyl or C? Al alkylene, and R 3 independently of each occurrence represents H, C-MO alkyl, C 2-4 alkylene, C 4-6 cycloalkyl, haloalkyl of C -4 or OH; and n represents an integer from 1, 000 to 20,000. 47. The composition according to claim 37, further characterized in that said agent against surface carbonization and flame retardant includes alumina trihydrate and magnesium hydroxide. 48. A silicone composition, comprising: (A) a silicone polymer and (B) two or more materials in the form of imparting particles of hydrophobic character imparting a property of a hydrophobic character to the composition or at least one material in the form of imparting particles of hydrophobic character that imparts a property of hydrophobic character to the composition and a filler. 49. The composition according to claim 48, further characterized in that (B) comprises at least one of calcium carbonate, silica, ground quartz, magnesium silicate or magnesium aluminum silicate. 50.- The composition according to claim 48, further characterized in that said two or more materials in the form of imparting particles of hydrophobic character comprise a mixture of calcium carbonate and magnesium carbonate or a mixture of magnesium silicate and calcium carbonate. . 51. An insulator comprising a housing portion, said housing portion comprising a cured product composition of (A) a silicone polymer and (B) a hydrophobic imparting particulate material, further characterized in that said material in the form of imparting particles of hydrophobic character imparts a property of hydrophobic character to said composition. 52. The insulator according to claim 51, further characterized in that the cured product composition excludes calcium carbonate, silica, ground quartz, magnesium silicate and magnesium aluminum silicate. 53. An insulator comprising a housing portion, said housing portion comprising a composition of cured product of (A) a silicone polymer and (B) two or more materials in the form of imparting particles of hydrophobic character further characterized in that said materials in the form of imparting particles of hydrophobic character impart a property of hydrophobic character to the composition or a hydrophobic imparting particulate material imparting a hydrophobic property to the composition and a filler. 54.- The insulator according to claim 53, further characterized in that (B) comprises at least one of calcium carbonate, silica, ground quartz, magnesium silicate or magnesium aluminum silicate. The insulator according to claim 53, further characterized in that said two or more materials in the form of imparting particles of hydrophobic character comprise a mixture of calcium carbonate and magnesium carbonate or a mixture of magnesium silicate and calcium carbonate. . 56.- A method of improving a recovery property of the hydrophobic character of a silicone polymer composition, comprising: determining a predicted recovery property of the hydrophobic character for a silicone composition; selecting a filler of hydrophobic imparting particulate material to impart said hydrophobic character recovery property to said silicone composition; and adding said filler in the form of hydrophobic imparting particles to a silicone composition in an amount to impart said expected recovery property of the hydrophobic character. 57.- A method of improving a hydrophobic property of a cured silicone polymer composition, comprising: determining a predicted hydrophobic property for a cured silicone composition; selecting a filler of hydrophobic imparting particulate material to impart said hydrophobic property to said silicone polymer composition; stirring a mixture of (A) a silicone polymer and (B) said selected inorganic filler; and heat to cure said mixture.