Silicone composition

Abstract

A silicone composition comprising (A) a conductive filler, (B) a polydiorganosiloxane polymer, (C) a polyorganohydrogensiloxane, (D) a hydrosilylation reaction catalyst, (E) a polymeric additive, and optionally (F) a hydrosilylation reaction inhibitor, has a low complex viscosity when mixed and provides high electrical conductivity when cured and good electrical conductivity retention after heat aging.

Description

[Technical Field]

[0001] The present invention relates to a silicone composition and a conductive silicone adhesive manufactured from such a composition.

[0002] Introduction Silicone adhesives are useful in a variety of applications, including automotive, electronics, construction, electrical appliances, and the aerospace industry. Due to the inherent insulating properties of silicone resins, silicone compositions require the incorporation of conductive fillers to improve the electrical performance of the cured products produced therefrom, for conductive applications such as conductive adhesives and electromagnetic interference (EMI) shielding materials.

[0003] While increasing the amount of conductive filler can improve the conductivity of silicone adhesives, the resulting highly filled silicone compositions are costly and difficult to achieve, especially when measuring the desired low complex viscosity—for example, a compound complex viscosity of 350,000 Pascal seconds (Pa·s) or less at room temperature (23±2 degrees Celsius (°C)) within two hours of mixing all components of the silicone composition together. Therefore, there is a continued need for silicone compositions that provide silicone adhesives with improved electrical performance while maintaining low complex viscosity for easy processability and application.

[0004] Furthermore, conductive metal fillers tend to oxidize over time and eventually become non-conductive. Silicone adhesives containing such fillers generally exhibit poor electrical stability at high temperatures (e.g., 80-150°C), which is indicated by a 10- to 100-fold increase in volume resistivity (VR) after one month of use at 80-125°C. Consequently, reducing the VR fluctuations of silicone adhesives after long-term thermal aging is also difficult.

[0005] It is desirable to discover a suitable silicone composition for preparing a conductive adhesive that does not have the aforementioned problems. [Overview of the project]

[0006] The present invention solves the problem of finding a silicone composition that does not have the above-mentioned problems. The present invention provides a novel silicone composition comprising a conductive filler (A), a polydiorganosiloxane polymer (B), a polyorganohydrogensiloxane (C), a hydrosilylation reaction catalyst (D), and a specific polymer additive (E), and optionally a hydrosilylation reaction inhibitor (F). The silicone composition has a complex viscosity of 350,000 Pascal seconds (Pa·s) or less at room temperature (23±2℃) when measured within 2 hours after mixing all the components in the silicone composition. The silicone composition also provides cured products such as silicone adhesives that have improved conductivity, as indicated by a lower volume resistivity (VR) during curing than cured products made from similar silicone compositions that do not contain only the polymer additive (E) (hereinafter, "existing silicone compositions"). The silicone composition of the present invention may also result in good retention of conductivity after thermal aging; for example, the cured product of the silicone composition shows less VR variation after thermal aging for 20 days or more at 125℃ compared to those made from existing silicone compositions. These above characteristics are measured according to the test methods described in the following Examples section.

[0007] In the first aspect, the present invention is expressed in a weight ratio based on the total weight of the silicone composition, (A) 66% to 89% conductive filler, (B) A polydiorganosiloxane polymer of formula (I) in an amount of 5% to 40%, (R 1 3SiO 1 / 2 )2(R 1 2SiO 2 / 2 ) n (I), In the formula, each R 1 The polyorganosiloxane polymer is a polydiorganosiloxane polymer of formula (I) in which the group is independently a monovalent aliphatic hydrocarbon group, n is in the range of 35 to 1,000, and the polyorganosiloxane polymer contains an average of at least 2 alkenyl groups per molecule. (C) A polyorganohydrogensiloxane of formula (II), (R 2 3SiO 1 / 2 )2(R 2 2SiO 2 / 2 ) m (II) In the formula, each R 2 is independently hydrogen or an alkyl group having 1 to 20 carbon atoms, m is in the range of 5 to 200, and the polyorganohydrogensiloxane has an average of at least 3 silicon-bonded hydrogen atoms per molecule. The polyorganohydrogensiloxane of formula (II) and (D) a hydrosilylation reaction catalyst, and (E) a polymer additive having a molecular weight of more than 2,000 to 20,000 g / mol at 0.1% to 1.5%, the polymer additive being selected from the group consisting of polypropylene glycol, an alcohol-initiated ethylene oxide and propylene oxide copolymer, or a mixture thereof, and (F) 0 to 0.3% of a hydrosilylation reaction inhibitor, to provide a silicone composition.

[0008] In a second aspect, the present invention provides a process for preparing the silicone composition of the first aspect. This process includes mixing a conductive filler, a polydiorganosiloxane polymer, a polyorganohydrogensiloxane, a hydrosilylation reaction catalyst, a polymer additive, and a hydrosilylation reaction inhibitor when used.

[0009] In a third aspect, the present invention provides a silicone adhesive containing a cured product of the silicone composition of the first aspect.

Embodiments for Carrying out the Invention

[0010] The silicone composition of the present invention comprises one or more conductive fillers as component (A). “Conductive filler” refers to any filler exhibiting an intrinsic resistivity of less than 1 ohm-centimeter (Ωcm) at 20°C, as determined by GB / T351-2019 (China national standard for metallic materials-resistivity measurement method). The conductive filler typically comprises particles having at least an outer surface of a metal selected from the group consisting of silver, gold, platinum, palladium, nickel, copper, or alloys thereof. The conductive filler may also comprise particles made of silver, gold, platinum, palladium, nickel, copper, or alloys thereof, preferably silver. Alternatively, the conductive filler may comprise particles having only an outer surface made of silver, gold, platinum, palladium, or alloys thereof, and a core (also referred to as “metal-coated particle”) distinct from the outer surface. The core of such particles may be any material, conductor, or insulator that supports the outer surface and does not adversely affect the electrical properties of the silicone adhesive (i.e., the cured product of the silicone composition) made from the silicone composition. Examples of such materials for the core include copper, graphite, aluminum, glass such as solid or hollow glass, mica, nickel, or ceramic fibers. Preferably, the conductive filler contains silver-coated particles. Examples of conductive fillers include silver-coated nickel particles, silver-coated aluminum particles, silver-coated copper particles, silver-coated glass particles, or mixtures thereof. The silver-coated particles typically have a silver content of 1% by weight or more, 2% by weight or more, 3% by weight or more, 4% by weight or more, 5% by weight or more, 6% by weight or more, 7% by weight or more, 8% by weight or more, 9% by weight or more, 10% by weight or more, 11% by weight or more, or 12% by weight or more, and at the same time, a silver content of 60% by weight or less, 55% by weight or less, 50% by weight or less, 45% by weight or less, or 40% by weight or less, based on the weight of the silver-coated particles as determined by inductively coupled plasma mass spectrometry (ICP-MS).

[0011] Conductive fillers useful in the present invention typically take the form of flakes, rods, fibers, or powders having spherical or other irregular shapes. Examples of conductive fillers useful in the present invention include fillers prepared by treating the surface of the aforementioned particles with at least one organosilicon compound. Suitable organosilicon compounds include those typically used to treat silica fillers, such as organochlorosilanes, organosiloxanes, organodisilazanes, organoalkoxysilanes, or mixtures thereof. The conductive filler may be a single conductive filler as described above, or a mixture of two or more such fillers differing in at least one of the following properties: composition, surface area, surface treatment, particle size, and particle shape.

[0012] In the present invention, a useful conductive filler may have a median particle size of 0.5 microns (μm) or more, 1 μm or more, 5 μm or more, 10 μm or more, 15 μm or more, 20 μm or more, 25 μm or more, 30 μm or more, 35 μm or more, or 40 μm or more, and at the same time, a median particle size of 100 μm or less, 90 μm or less, 80 μm or less, 75 μm or less, 70 μm or less, 65 μm or less, 60 μm or less, or 50 μm or less. In the present invention, "median particle size" refers to the D50 particle size measured according to the test method described in the following Examples section.

[0013] Methods for preparing conductive fillers suitable for use in the silicone composition of the present invention are well known in the art. For example, powders of silver, gold, platinum, or palladium, or alloys thereof, are typically produced by chemical precipitation, electrolysis, or cementation. Flakes of the above metals are typically produced by grinding or milling metal powders. Particles having only at least one outer surface of the above metals are typically produced by metallizing a suitable core material using methods such as electrolysis, electrolysis, or vacuum deposition. If the conductive filler is a filler prepared by treating the surface of the particles with an organosilicon compound, the particles may be treated before mixing with other components of the silicone composition, or the particles may be treated in situ during the preparation of the silicone composition.

[0014] The conductive filler in the silicone composition of the present invention may be present in an amount that imparts a desired viscosity to the silicone composition and imparts conductivity to the silicone adhesive produced from the silicone composition. The desired complex viscosity of the silicone composition is typically 350,000 Pa.s or less at room temperature (23±2℃) when measured within 2 hours after mixing all the components of the silicone composition together, as determined according to the test methods described in the following Examples section. The concentration of the conductive filler depends on the desired electrical properties, the surface area of ​​the filler, the density of the filler, the shape of the filler particles, the surface treatment of the filler, and the properties of other components in the silicone composition. The conductive filler may be present in an amount of 66% or more, 69% or more, 70% or more, 70% or more, 71% or more, or 72% or more, based on the total weight of the silicone composition, and at the same time, 89% or less, 88% or less, 87% or less, 86% or less, 85% or less, 84% or less, 83% or less, or 82% or less.

[0015] In the present invention, useful conductive fillers can be selected from two or more of the following three types of conductive fillers: (a1) silver-coated nickel particles, (a2) silver-coated aluminum particles, and (a3) ​​silver-coated glass particles, or a combination thereof. For example, silver-coated nickel particles (a1) may be present in amounts of 0 or more, 35% or more by weight, 40% or more by weight, 45% or more by weight, 50% or more by weight, or 55% or more by weight, based on the total weight of the silicone composition, and at the same time, in amounts of 89% or less by weight, 88% or less by weight, 87% or less by weight, 86% or less by weight, 85% or less by weight, 84% or less by weight, or 83% or less by weight. Silver-coated aluminum particles (a2) may be present in amounts of 0 or more, 15% or more by weight, 18% or more by weight, 20% or more by weight, 22% or more by weight, 25% or more by weight, or 27% or more by weight, based on the total weight of the silicone composition, and at the same time in amounts of 82% or less by weight, 80% or less by weight, 78% or less by weight, 73% or less by weight, 70% or less by weight, 68% or less by weight, or 66% or less by weight, based on the total weight of the silicone composition. Silver-coated glass particles (a3) ​​may be present in amounts of 0 or more, 15% or more by weight, 20% or more by weight, 25% or more by weight, 30% or more by weight, 40% or more by weight, 50% or more by weight, 60% or more by weight, 70% or more by weight, or 72% or more by weight, and at the same time in amounts of 82% or less by weight, 80% or less by weight, 78% or less by weight, 76% or less by weight, and further, 73% or less by weight, based on the total weight of the silicone composition.

[0016] The silicone composition of the present invention also comprises one or more polydiorganosiloxane polymers as component (B). The polydiorganosiloxane polymer has formula (I). (R 1 3SiO 1 / 2 )2(R 1 2SiO 2 / 2 ) n (I) In the formula, each R 1 The group is independently a monovalent aliphatic hydrocarbon group, n is in the range of 35 to 1,000, and the polyorganosiloxane polymer contains an average of at least two alkenyl groups per molecule.

[0017] The value of n in equation (I) can be 35 or greater, 50 or greater, 100 or greater, 150 or greater, 200 or greater, 250 or greater, or 300 or greater, and at the same time, 1,000 or less, 900 or less, 800 or less, 700 or less, 650 or less, or 600 or less.

[0018] Suitable monovalent aliphatic hydrocarbon groups may include alkyl groups and alkenyl groups. "Alkyl" refers to a cyclic, branched, or unbranched saturated monovalent hydrocarbon group. 1 The alkyl groups represented by typically have 1 to 20 carbon atoms, 1 to 12 carbon atoms, 1 to 10 carbon atoms, 1 to 6 carbon atoms, 1 to 3 carbon atoms, or 1 to 2 carbon atoms. Examples of preferred alkyl groups include methyl, ethyl, propyl (e.g., isopropyl and / or n-propyl), butyl (e.g., isobutyl, n-butyl, tert-butyl, and / or sec-butyl), pentyl (e.g., isopentyl, neopentyl, and / or tert-pentyl), hexyl, heptyl, octyl, nonyl, and decyl, as well as branched alkyl groups with 6 or more carbon atoms, and cyclic alkyl groups such as cyclopentyl and cyclohexyl. A preferred alkyl group is methyl. "Alkenyl" means a branched or unbranched monovalent hydrocarbon group having one or more carbon-carbon double bonds. 1 The alkenyl group represented by typically has 2 to 10 carbon atoms, 2 to 8 carbon atoms, or 2 to 6 carbon atoms. Suitable examples of alkenyl groups include vinyl, allyl, propenyl (e.g., isopropenyl and / or n-propenyl), butenyl, pentenyl, hexenyl, and heptenyl (including branched and linear isomers of 4 to 7 carbon atoms), and cyclohexenyl. Preferably, the alkenyl group is vinyl. The alkenyl group in the polydiorganosiloxane polymer may be located at the terminal position, the pendant position, or both the terminal and pendant positions. Preferably, R 1At least 50 mol%, 60 mol%, 70 mol%, or 80 mol% or more of the monovalent aliphatic hydrocarbon group represented by is methyl. The molar percentage of methyl in this specification can be determined by nuclear magnetic resonance (NMR) analysis. Examples of polydiorganosiloxane polymers useful in the present invention include ViMe2SiO(Me2SiO) n SiMe2Vi, ViMe2SiO(Me2SiO) 0.98n (MeViSiO) 0.02n SiMe2Vi and Me3SiO(Me2SiO) 0.95n (MeViSiO) 0.05n SiMe3 may also be given, where Me and Vi represent methyl and vinyl, respectively, and n is as defined above.

[0019] Examples of suitable polydiorganosiloxane polymers include: b1) dimethylvinylsiloxy-terminated polydimethylsiloxane, b2) dimethylvinylsiloxy-terminated poly(dimethylsiloxane / methylvinylsiloxane), b3) dimethylvinylsiloxy-terminated polymethylvinylsiloxane, b4) trimethylsiloxy-terminated poly(dimethylsiloxane / methylvinylsiloxane), b5) trimethylsiloxy-terminated polymethylvinylsiloxane, b6) dimethylvinylsiloxy-terminated poly(dimethylsiloxane / methylvinylsiloxane), b7) dimethylvinylsiloxy-terminated poly(dimethylsiloxane / methylphenylsiloxane), b8) dimethylvinylsiloxy-terminated poly(dimethylsiloxane / diphenylsiloxane), b9) Examples include polydimethylsiloxanes with phenyl, methyl, or vinylsiloxy terminations, b10) polydimethylsiloxanes with dimethylhexenylsiloxy terminations, b11) poly(dimethylsiloxane / methylhexenylsiloxane) with dimethylhexenylsiloxy terminations, b12) polymethylhexenylsiloxy terminations, b13) poly(dimethylsiloxane / methylhexenylsiloxane) with trimethylsiloxy terminations, b14) polymethylhexenylsiloxanes with trimethylsiloxy terminations, b15) poly(dimethylsiloxane / methylhexenylsiloxane) with dimethylhexenylsiloxy terminations, b16) poly(dimethylsiloxane / methylhexenylsiloxane) with dimethylvinylsiloxy terminations, or combinations thereof. Preferably, the polydiorganosiloxane polymer is selected from the group consisting of b1) dimethylvinylsiloxy-terminated polydimethylsiloxane, b2) dimethylvinylsiloxy-terminated poly(dimethylsiloxane / methylvinylsiloxane), or a combination of b1) and b2).

[0020] Polydiorganosiloxane polymers are well known in the art and may be prepared by methods such as hydrolysis and condensation of the corresponding organohalosilane, or equilibration of cyclic polydiorganosiloxanes.

[0021] The polydiorganosiloxane polymer may be a single polydiorganosiloxane, or it may be a mixture of two or more polydiorganosiloxanes that differ in at least one of the following characteristics: structure, average molecular weight, siloxane units, and sequence.

[0022] In the present invention, polydiorganosiloxane polymers useful in this invention may be present in the silicone composition in amounts of 5% or more by weight, 6% or more by weight, 7% or more by weight, 7.5% or more by weight, 9% or more by weight, 10% or more by weight, 12% or more by weight, 15% or more by weight, 18% or more by weight, or 20% or more by weight, and at the same time, in amounts of 40% or less by weight, 38% or less by weight, 35% or less by weight, 32% or less by weight, 30% or less by weight, 28% or less by weight, or 25% or less by weight, based on the total weight of the silicone composition.

[0023] The silicone composition of the present invention comprises one or more polyorganohydrogensiloxanes as component (C). The polyorganohydrogensiloxane has formula (II). (R 2 3SiO 1 / 2 )2(R 2 2SiO 2 / 2 ) m (II) In the formula, each R 2 R is independently a hydrogen atom or an alkyl group, m is in the range of 5 to 200, and the polyorganohydrogensiloxane has an average of at least 3 silicon-bonded hydrogen atoms (SiH) per molecule. 2 The alkyl group represented by may have 1 to 20 carbon atoms, 1 to 12 carbon atoms, 1 to 10 carbon atoms, 1 to 6 carbon atoms, 1 to 3 carbon atoms, or 1 to 2 carbon atoms, including methyl, ethyl, propyl, and butyl.

[0024] The value of m in equation (II) may be 5 or greater, 7 or greater, 10 or greater, 20 or greater, 30 or greater, 40 or greater, or 50 or greater, and at the same time, 200 or less, 150 or less, 140 or less, 130 or less, 120 or less, 110 or less, or 100 or less.

[0025] Polyorganohydrogensiloxanes useful in the present invention may contain silicon-bonded hydrogen atoms in amounts of 0.38% by weight or more, 0.5% by weight or more, 0.6% by weight or more, or 0.75% by weight or more, and simultaneously in amounts of 2% by weight or less, 1.9% by weight or less, 1.8% by weight or less, 1.75% by weight or less, 1.7% by weight or less, or 1.6% by weight or less, based on the weight of the polyorganohydrogensiloxane. The content of silicon-bonded hydrogen atoms can be determined by NMR analysis.

[0026] Methods for preparing polyorganohydrogensiloxanes, such as hydrolysis and condensation of organohydridohalosilanes, are well known in the art. Examples of suitable polyorganohydrogensiloxanes include: c1) trimethylsiloxy-terminated poly(dimethyl / methylhydrogen)siloxane, c2) trimethylsiloxy-terminated polymethylhydrogensiloxane, c3) dimethylhydrogensiloxy-terminated polydimethylsiloxane, c4) dimethylhydrogensiloxy-terminated poly(dimethylsiloxane / methylhydrogensiloxane), c5) dimethylhydrogensiloxy-terminated polymethylhydrogensiloxane, and c6) H(CH3)2SiO 1 / 2 Units and SiO 4 / 2 Examples include resins essentially derived from units, or combinations thereof.

[0027] The polyorganohydrogensiloxane is present in an amount sufficient to ensure that the molar ratio (referred to as the SiH / Vi ratio) of silicon-bonded hydrogen atoms in the polyorganohydrogensiloxane to alkenyl groups in all components of the silicone composition (including alkenyl groups in the polydiorganosiloxane polymer (B) and, if used, alkenyl groups in other components containing alkenyl groups such as the polyorganosilicate resin (G) described below) is 0.5 to 10, for example, 0.7 to 8, 0.8 to 7, 0.9 to 6, 1 to 5, or 1.05 to 2. The silicone composition typically contains polyorganohydrogensiloxane in amounts of 0.2% by weight or more, 0.3% by weight or more, 0.4% by weight or more, 0.5% by weight or more, and simultaneously 2% by weight or less, 1.8% by weight or less, 1.6% by weight or less, 1.5% by weight or less, or 1.2% by weight or less, based on the total weight of the silicone composition.

[0028] The silicone composition of the present invention, constituent components ( E The polymer additive comprises one or more polymer additives. The polymer additive is selected from the group consisting of polypropylene glycol (PPG), alcohol-initiated ethylene oxide and propylene oxide copolymer (hereinafter referred to as "alcohol-initiated EO / PO copolymer"), or mixtures thereof.

[0029] A polymer additive useful in the present invention may have 2 or more, 2.1 or more, 2.5 or more, or 3 or more hydroxyl groups per molecule, and simultaneously have an average number of 12 or less, 10 or less, 8 or less, or 6 or less.

[0030] Preferably, the polymer additive useful in the present invention comprises one or more alcohol-initiated EO / PO copolymers. The alcohol-initiated EO / PO copolymer may be a linear or branched random copolymer.

[0031] The alcohol-initiated EO / PO copolymer useful in the present invention may have the structure of formula (III). (A) z B(III) A is HO-(CHR p -CHR q -O) x -(CH2-CH2-O) y - represents x is 8 to 40, y is 1 to 20, R p and R q Unlike other groups, z is selected from hydrogen and -CH3, z is 1 to 12, and B is hydrogen or a monovalent, divalent, or polyvalent hydrocarbon group having 3 to 18 carbon atoms.

[0032] The arrangement of ethylene oxide units (-CH2CH2-O)- and propylene oxide units (-(CH2CHCH3-O)-) in segment A of formula (III) may be random, or they may be oriented in any type of block configuration, such as a single block of ethylene oxide units and a single block of propylene oxide units.

[0033] In equation (III), x and y are the average number of propylene oxide units and ethylene oxide units, respectively. The value of x can be 8-40, 10-35, 15-30, or 20-28. The value of y can be 1-20, 1-18, or 1-16.

[0034] In equation (III), z can be 1-12, 2-10, 3-8, or 4-6.

[0035] In equation (III), the value of (x+y+z) is sufficient to give the molecular weights listed below for alcohol-initiated EO / PO copolymers.

[0036] In formula (III), B may have 3 to 18 carbon atoms, 3 or 12 carbon atoms, 3 to 10 carbon atoms, 3 to 8 carbon atoms, or 4 to 6 carbon atoms.

[0037] If B is a monovalent or divalent hydrocarbon group, formula (III) represents a linear structure. If B is a polyvalent (e.g., trivalent or higher) hydrocarbon group, formula (III) represents a branched structure. B can be a group derived from sorbitol as follows: [ka]

[0038] Alternatively, B may be a group derived from glycerol, as follows: [ka]

[0039] Alcohol-initiated EO / PO copolymers useful in the present invention can be prepared from an alcohol initiator having three or more carbon atoms, four or more carbon atoms, five or more carbon atoms, or six or more carbon atoms, and simultaneously having typically 18 or fewer carbon atoms, 12 or fewer carbon atoms, 10 or fewer carbon atoms, 8 or fewer carbon atoms, or 6 or fewer carbon atoms. The alcohol initiator may be a straight-chain alcohol or a branched-chain alcohol, preferably a branched-chain alcohol. The alcohol initiator may be a mono, diol, triol, tetrol, pentol, or hexol. Preferably, the alcohol initiator is hexol. Preferably, the alcohol initiator for preparing the EO / PO copolymer is sorbitol, glycerol, or a mixture thereof. The methods and conditions used for preparing the alcohol-initiated EO / PO copolymer are well known to those skilled in the art, and are, for example, temperatures in the range of 20 to 180°C or 100 to 160°C. Preparation of alcohol-initiated EO / PO copolymers can be found, for example, in J. Herzberger et al., "Polymerization of ethylene oxide, propylene oxide, and other alkylene oxides: synthesis, novel polymer architectures, and bioconjugation," Chemical Reviews, Volume 116, Issue No. 4, pp. 2170-2243 (2016).

[0040] In the present invention, alcohol-initiated EO / PO copolymers useful in this invention may contain propylene oxide units (also as propylene oxide chains) in amounts of 50% or more by weight, 52% or more by weight, 55% or more by weight, 58% or more by weight, 60% or more by weight, 62% or more by weight, or 65% or more by weight, based on the weight of the alcohol-initiated EO / PO copolymer, and simultaneously in amounts of 99% or less by weight, 98% or less by weight, 97% or less by weight, 96% or less by weight, or 95% or less by weight.

[0041] Useful polymer additives in the present invention include those with a concentration exceeding 2,000 g / mol, for example, 2,100 g / mol or more, 2,200 g / mol or more, 2,300 g / mol or more, 2,500 g / mol or more, 2,600 g / mol or more, 2,700 g / mol or more, 2,800 g / mol or more, 2,900 g / mol or more, 3,000 g / mol or more, 3,200 g / mol or more, 3,500 g / mol or more, 3,800 g / mol or more, 4,000 g / mol or more, 4,500 g / mol or more, 5,000 g / mol or more, 5,500 g / mol or more, 6,0 The molecular weight is 00 g / mol or more, 6,500 g / mol or more, 7,000 g / mol or more, 7,500 g / mol or more, 8,000 g / mol or more, or 9,000 g / mol or more, and simultaneously, 20,000 g / mol or less, 19,000 g / mol or less, 18,000 g / mol or less, 17,000 g / mol or less, 16,000 g / mol or less, 15,000 g / mol or less, 14,000 g / mol or less, 13,000 g / mol or less, 12,000 g / mol or less, 11,000 g / mol or less, or 10,000 g / mol or less. In this specification, molecular weight is the number average molecular weight (M n ) refers to (56100*f / OHV, calculated by the formula, where f represents the average number of hydroxyl groups per molecule of the polymer additive (also called the "OH functional value"), and OHV represents the hydroxyl value of the polymer additive in units of mg KOH / g, as determined by ASTM D4274-2011.

[0042] The silicone composition of the present invention may contain, based on the total weight of the silicone composition, 0.1% or more by weight, 0.12% or more by weight, 0.15% or more by weight, 0.18% or more by weight, 0.2% or more by weight, 0.22% or more by weight, 0.25% or more by weight, 0.28% or more by weight, or 0.3% or more by weight, and at the same time, 1.5% or less by weight, 1.4% or less by weight, 1.3% or less by weight, 1.2% or less by weight, 1.1% or less by weight, 1% or less by weight, 0.9% or less by weight, 0.8% or less by weight, or 0.7% or less of polymer additives.

[0043] The silicone composition of the present invention, constituent components ( D) comprises one or more hydrosilylation catalysts. The hydrosilylation catalyst can promote the addition reaction between component (B) and component (C). Examples of hydrosilylation catalysts include platinum group metal catalysts. Such hydrosilylation catalysts include ( d 1) A metal selected from platinum, rhodium, ruthenium, palladium, osmium, and iridium, preferably platinum, ( d 2) For example, rhodium diphosphine chelates such as chloride tris(triphenylphosphine)rhodium(I) (Wilkinson catalyst), [1,2-bis(diphenylphosphino)ethane]dichlorodirhodium or [1,2-bis(diethylphosphino)ethane]dichlorodirhodium], chloroplatinic acid (Spear catalyst), chloroplatinic acid hexahydrate, or compounds such as metals containing platinum dichloride, ( d 3) Complexes of platinum group compounds and low molecular weight organopolysiloxanes, d 4) Platinum group compounds microencapsulated in a matrix or core-shell structure, or combinations thereof, d 5) The complex may be microencapsulated in a resin matrix, or a combination thereof. Examples of platinum-low molecular weight organopolysiloxane complexes include the platinum complex of 1,3-diethenyl-1,1,3,3-tetramethyldisiloxane (Karstedt catalyst). Representative hydrosilylation reaction catalysts are described in U.S. Patents 3,159,601 and 3,220,972.

[0044] The concentration of the hydrosilylation catalyst is sufficient to catalyze the hydrosilylation reaction of silicon-bonded hydrogen atoms and alkenyl groups. Typically, the concentration of the hydrosilylation catalyst is sufficient to provide platinum group metals in concentrations of parts per million (ppm) or more, 5 ppm or more, 10 ppm or more, 20 ppm or more, or 30 ppm or more, based on the total weight of the silicone composition, while simultaneously providing platinum group metals in concentrations of 6,000 ppm or less, 5,000 ppm or less, 4,000 ppm or less, 3,000 ppm or less, 2,000 ppm or less, 1,000 ppm or less, 500 ppm or less, 100 ppm or less, or 50 ppm or less.

[0045] The silicone composition of the present invention may contain one or more hydrosilylation reaction inhibitors (inhibitors) as component (F), which may be used optionally to change the reaction rate between silicon-bonded hydrogen atoms and alkenyl groups in the silicone composition compared to the reaction rate of the same starting material without the inhibitors. Suitable inhibitors include acetylene alcohols such as methylbutynol, ethinylcyclohexanol, dimethylhexynol, and 3,5-dimethyl-1-hexyn-3-ol, 1-butin-3-ol, 1-propyne-3-ol, 2-methyl-3-butin-2-ol, 3-methyl-1-butin-3-ol, 3-methyl-1-pentin-3-ol, 3-phenyl-1-butin-3-ol, 4-ethyl-1-octin-3-ol, 3,5-dimethyl-1-hexyn-3-ol, and 1-ethynyl-1-cyclohexanol, and combinations thereof, and methylvinylcyclosiloxanes such as 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane, 1,3,5,7-tetramethyl-1,3,5,7-tetrahexenylcyclotetrasiloxane, and combinations thereof. Examples include oalkenylsiloxane, en-yine compounds such as 3-methyl-3-penten-1-yine, 3,5-dimethyl-3-hexen-1-yine, and combinations thereof, triazoles such as benzotriazole, phosphine, mercaptan, hydrazine, amines such as tetramethylethylenediamine, 3-dimethylamino-1-propyne, n-methylpropargylamine, propargylamine, and 1-ethynylcyclohexylamine, maleates such as dialkyl fumarate such as diethyl fumarate, diallyl fumarate, dialkoxyalkyl fumarate, diallyl maleate, and diethyl maleate, nitriles, ethers, carbon monoxide, alkenes such as cyclooctadiene and divinyltetramethyldisiloxane, and alcohols such as benzyl alcohol, or combinations thereof.

[0046] In the present invention, hydrosilylation reaction inhibitors useful in this invention may be present in the silicone composition in amounts of 0 or more, 0.01% or more by weight, 0.02% or more by weight, 0.03% or more by weight, 0.05% or more by weight, or 0.1% or more by weight, based on the total weight of the silicone composition, and simultaneously in amounts of 0.3% or less by weight, 0.25% or less by weight, 0.2% or less by weight, or 0.15% or less by weight.

[0047] The silicone composition of the present invention may contain one or more polyorganosilicate resins as component (G). The polyorganosilicate resin is of formula R M 3SiO 1 / 2 A single functional unit ("M" unit), and formula SiO 4 / 2 It contains a tetrafunctional silicate unit ("Q" unit), where each R M R is independently alkyl or alkenyl. M The alkyl groups represented by typically have 1 to 6 carbon atoms or 1 to 3 carbon atoms. Examples of alkyl groups include methyl, ethyl, propyl, pentyl, hexyl, and cyclohexyl. M The alkenyl group represented by typically has 2 to 6 carbon atoms. Examples of alkenyl groups include vinyl, allyl, butenyl, and hexenyl. Preferably, the alkyl group is methyl and the alkenyl group is vinyl.

[0048] Polyorganosilicate resins useful in the present invention are typically R M 3SiO 1 / 2 Units and SiO 4 / 2 Essentially consisting of units. "Essentially consisting of" means that the total amount of M units and Q units in the polyorganosilicate resin is 98% by weight or more, based on the total weight of the polyorganosilicate resin. Polyorganosilicate resin is also HOSiO 3 / 2It contains units (TOH units), which account for the silicon-bonded hydroxyl content of the polyorganosilicate resin. The silicon-bonded hydroxyl content of the polyorganosilicate resin, as determined by NMR analysis, is typically less than 2% by weight or less than 1% by weight based on the total weight of the polyorganosilicate resin. The polyorganosilicate resin is a by-product in the preparation of the resin according to the method of Daudt et al., as described in U.S. Patent Application Publication No. 2,676,182, with formula (R M The material may also contain a neopentamer organopolysiloxane having SiO)4Si, which is incorporated herein by reference to teach a method for preparing a polyorganosilicate resin.

[0049] The molar ratio of M units to Q units in polyorganosilicate resins is typically in the range of 0.5–1.5, 0.65–1.3, or 0.8–1.2, as determined by NMR analysis. The M / Q ratio represents the total number of M units versus the total number of Q units in the polyorganosilicate resin, including contributions from any neopentamers present.

[0050] Polyorganosilicate resins useful in the present invention may contain, on average, 3 mol% or more, 4 mol% or more, or 5 mol% of alkenyl groups, and simultaneously, 20 mol% or less, 17 mol% or less, or 15 mol% or less. The molar percentage of alkenyl groups in the resin is defined herein as the ratio of the number of moles of alkenyl group-containing siloxane units in the resin to the total number of moles of siloxane units in the resin, multiplied by 100%. The total number of moles of siloxane units in the resin includes the above-mentioned M, Q, and TOH units, which can be determined by NMR analysis.

[0051] A preferred polyorganosilicate resin is CH=CH(CH3)2SiO 1 / 2 Unit: (CH3)3SiO 1 / 2 Units, and SiO 4 / 2 Essentially derived from the unit, where M is the unit (CH=CH(CH3)2SiO 1 / 2 Units and (CH3)3SiO 1 / 2Units) versus Q units (i.e., SiO 4 / 2 The unit is 0.8, and the resin contains 5 mol% and 1.8 wt% vinyl groups. The weight percentage of vinyl groups in the resin, as determined by NMR analysis, is defined here as the total molar weight of vinyl groups in the resin multiplied by 100% relative to the molecular weight of the resin.

[0052] The silicone composition of the present invention may contain one or more adhesion promoters as component (H). The adhesion promoter may include alkoxysilanes containing unsaturated or epoxy-functionalized alkoxysilanes, combinations of alkoxysilanes and hydroxy-functionalized polyorganosiloxanes (i.e., physical blends and / or reaction products), or mixtures thereof. Examples of suitable epoxy-functionalized alkoxysilanes include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, (epoxycyclohexyl)ethyldimethoxysilane, (epoxycyclohexyl)ethyldiethoxysilane, or mixtures thereof. Examples of suitable unsaturated alkoxysilanes include vinyltrimethoxysilane, allyltrimethoxysilane, allyltriethoxysilane, hexenyltrimethoxysilane, undecylenyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropyltriethoxysilane, 3-acryloyloxypropyltrimethoxysilane, 3-acryloyloxypropyltriethoxysilane, or mixtures thereof.

[0053] Preferably, the adhesion promoter is a reaction product and / or blend of an epoxy-functionalized alkoxysilane with a hydroxy-terminated polyorganosiloxane such as a hydroxy-terminated vinyl polyorganosiloxane. The adhesion promoter may also include a combination of 3-glycidoxypropyltrimethoxysilane and a hydroxy-terminated vinyl polydimethylsiloxane (i.e., a physical blend and / or reaction product), preferably a blend and / or reaction product of 3-glycidoxypropyltrimethoxysilane and a hydroxy-terminated methylvinyl / dimethylsiloxane copolymer. Suitable commercially available adhesion promoters include, for example, SYL-OFF® 297, SYL-OFF® 397, and SYL-OFF® SL9250, all available from Dow Silicones Corporation (Midland, Michigan, USA) (SYL-OFF is a trademark of Dow Silicones Corporation).

[0054] In the present invention, useful adhesion promoters may be present in the silicone composition in amounts of zero or more, 0.01% or more by weight, 0.05% or more by weight, 0.1% or more by weight, or 0.5% or more by weight, based on the total weight of the silicone composition, and simultaneously in amounts of 5% or less by weight, 4.5% or less by weight, 4% or less by weight, 3.5% or less by weight, 3% or less by weight, 2.5% or less by weight, 2% or less by weight, 1.5% or less by weight, or 1% or less by weight, based on the total weight of the silicone composition.

[0055] In addition to the above components, the silicone composition of the present invention may further contain one or more of the following additives: fillers other than conductive fillers, pigments, and antioxidants. These additives may be present in the silicone composition in a total amount of 0 to 0.5% by weight, 0.01% to 0.2% by weight, or 0.05% to 0.15% by weight, based on the total weight of the silicone composition.

[0056] The silicone compositions of the present invention can be prepared by mixing components (A) to (E) and (F) (if used), as well as any of the above components, typically at room temperature. The silicone compositions may be one-component or multi-component compositions. The mixing of the components in the silicone composition can be achieved by any of the techniques well known in the art, such as grinding, blending, and stirring, either in a batch or continuous process. The silicone compositions can be prepared without the aid of a solvent while still achieving the desired low complex viscosity. Therefore, the silicone compositions of the present invention may be solvent-free (i.e., contain no solvent or may contain trace amounts of residual solvent from the delivery of the components in the silicone composition). In this specification, "low complex viscosity" refers to a complex viscosity of a silicone composition that is 350,000 Pa·s or less at room temperature when all components of the silicone composition are mixed together and measured within 2 hours, for example, a complex viscosity of 1,000 Pa·s or more, 1,500 Pa·s or more, 2,000 Pa·s or more, and simultaneously 350,000 Pa·s or less, 200,000 Pa·s or less, 100,000 Pa·s or less, 20,000 Pa·s or less, 15,000 Pa·s or less, or 10,000 Pa·s or less, when measured according to the test method described in the Examples section below. The silicone compositions of the present invention are typically stored in sealed containers to prevent exposure to air and moisture. The silicone compositions of the present invention may be stored at room temperature for several weeks, or at a temperature below 0°C, preferably -30 to -20°C, for several months, without altering the properties of the cured product (e.g., silicone adhesive) made from the silicone composition. The silicone composition of the present invention may be more stable than similar silicone compositions (i.e., existing silicone compositions) that do not contain only the polymer additive (E). For example, the silicone composition of the present invention does not exhibit visible oily liquid bleed-out from the surface (i.e., does not exhibit a glossy surface) after being stored at room temperature for more than three months.

[0057] The silicone composition of the present invention is useful for a variety of applications. For example, the silicone composition cures to form conductive adhesives, conductive coatings, electromagnetic interference (EMI) shielding materials, release coatings, molding compounds, and protective coating materials for electronic circuits, planes, fibers or small particles, or gasket materials. The silicone composition is a curable composition. Upon curing, the silicone composition forms a cured product with high conductivity. Here, "high conductivity" means that the volume resistivity measured in accordance with the Chinese national standard GB / T1552-1995 (China national standard test method for measuring resistivity of monocrystal silicon and germanium with a collinear four-probe array) is 0.01 ohms cm or less, preferably 0.001 ohms cm or less, and more preferably 0.0001 ohms cm or less. The silicone composition of the present invention is particularly useful in the manufacture of conductive silicone adhesives.

[0058] The present invention also relates to a silicone adhesive comprising a cured product of a silicone composition, i.e., a silicone adhesive formed by curing a silicone composition by a hydrosilylation reaction. The silicone adhesive may be used to form an adhesive article on a substrate by applying the silicone composition to the substrate. The application of the silicone composition to the substrate can be carried out by various means, such as dispensing, spinning, spraying, atomizing, dipping, pouring, screen printing, and extrusion molding, or by using a brush, roller, or coating bar. The substrate can be any material that can withstand the curing conditions described below and is used to cure the silicone composition to form a silicone adhesive on the substrate. Suitable substrates include, for example, epoxy, polycarbonate, poly(butylene terephthalate) resin, polyamide resin and blends thereof, such as blends of polyamide resin with syndiotactic polystyrene, acrylonitrile-butadiene-styrene, styrene-modified poly(phenylene oxide), poly(phenylene sulfide), vinyl ester, polyphthalamide, polyimide, silicon, aluminum, stainless steel alloy, titanium, copper, nickel, silver, gold, or combinations thereof, preferably substrates that can be used in electronic applications. For example, the present invention may provide an electronic device comprising a substrate and a silicone composition or silicone adhesive disposed on the substrate. Curing of the silicone composition may be carried out at room temperature or at a high temperature up to 200°C, for example, 70-200°C or 125-175°C, for a time sufficient to cure the silicone composition (e.g., 1-3 hours). Compared with existing silicone compositions, the silicone compositions of the present invention cure to form a silicone adhesive having improved conductivity, as indicated by a lower volume resistivity. For example, a silicone adhesive made from the silicone composition of the present invention may exhibit a volume resistivity (VR) reduction of at least 50% compared to a silicone adhesive made from an existing silicone composition, for example, a VR reduction of at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, or at least 99%. The silicone adhesive of the present invention may exhibit high conductivity as described above.The silicone adhesives of the present invention may also exhibit better retention of these electrical properties during thermal cycling at 125°C for at least 20 days, 30 days or more, or 60 days or more. For example, the VR variation of the silicone adhesives of the present invention may show a reduction of at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, or at least 99% compared to the VR variation of silicone adhesives made from existing silicone compositions.

[0059] The present invention also provides a method for bonding a first substrate to a second substrate. This method comprises (i) applying a silicone composition to at least one surface of the substrates, (ii) bringing the two substrates into contact with the silicone composition present between them, and (iii) curing the silicone composition. The two substrates are those described above and may be the same or different. The curing of the silicone composition may be carried out as described above. [Examples]

[0060] Next, some embodiments of the present invention will be described in the following examples, all parts and percentages are by weight unless otherwise specified. The following materials are used in the examples.

[0061] The following are examples of conductive fillers available from Potters Industries: CONDUCT-O-FIL(TM) SN08P40 silver-coated nickel granule particles (particle size: 8 μm, silver content 40% by weight), CONDUCT-O-FIL SN40P18 silver-coated nickel granules, particle size 40 μm (silver content 18 wt%). CONDUCT-O-FIL S3000S3N silver-coated glass spherical particles (particle size: 34 μm, silver content 12% by weight), and CONDUCT-O-FIL SA300S20 silver-coated aluminum granules (particle size: 40 μm, silver content: 20% by weight) (CONDUCT-O-FIL is a trademark of Potters Industries, Inc.).

[0062] 1-ethinyl-1-cyclohexanol (ETCH), available from TCI, is used as the inhibitor.

[0063] Inhibitor A, available from TCI, is 3,5-dimethyl-1-hexyn-3-ol.

[0064] The platinum (Pt) catalyst available from Gelest is SIP6831.2 platinum-divinyltetramethyldisiloxane complex in xylene, 2% Pt (based on the weight of the Pt catalyst).

[0065] All of the following materials are available from Dow Silicones Corporation.

[0066] Hydride polydimethylsiloxane (PDMS) is (CH3)3SiO-[(CH3)2SiO] 3.34 -[HCH3SiO] 5.32 It has the structure -Si(CH3)3.

[0067] Vinyl-terminated PDMS is CH2=CH-(CH3)2SiO-[(CH3)2SiO] m It has the structure -Si(CH3)2-CH=CH2, where m is 162, 324, 41, and 554 for vinyl-terminated PDMS-A, vinyl-terminated PDMS-B, vinyl-terminated PDMS-C, and vinyl-terminated PDMS-D, respectively.

[0068] The vinyl-capped MQ resin has an average chemical structure: M Vi 0.05 M 0.4 Q 0.55 It has a Vi content of 5 mol% and 1.8 wt% (the molar and wt content of Vi groups are as defined in the chapter on polyorganosilicate resins above), and in the formula, M Vi CH2=CH(CH3)2SiO 1 / 2 This indicates that Vi represents CH2=CH-.

[0069] DOWSIL™ 193C Fluid ("DC-193C SPE") is a silicone-modified polyether (as measured by GPC below, M n (The concentration is 3,096 g / mol, and DOWSIL is a trademark of Dow Silicones Corporation).

[0070] The adhesion promoter is a combination of glycidoxypropyltrimethoxysilane and hydroxy-terminated methyl vinyl / dimethylsiloxane copolymer.

[0071] All of the polyols listed in the table below are available from The Dow Chemical Company. [Table 1] 1 OHV represents the hydroxyl value of an alcohol alkoxylate as determined by ASTM D4274-2011, N / A - Unavailable. 2 Mn is calculated using 56100 (mg / mol) * f / OHV (mgKOH / g), 3 The weight percentage of PO refers to the weight content of propylene oxide units relative to the total weight of the alcohol alkoxylate. CARBOWAX, TERGITOL, and DOWFAX are trademarks of The Dow Chemical Company.

[0072] In the examples and in determining the properties and characteristics described herein, the following standard analytical instruments and methods are used.

[0073] NMR As described in Reference Example 2 in column 32 of U.S. Patent No. 9,593,209. 29 Si and 13 Using 1C nuclear magnetic resonance (NMR) technology, the molar percentage of methyl, the weight content of silicon-bonded hydrogen atoms, the silicon-bonded hydroxyl content, and M(R) are determined. M 3SiO 1 / 2 ) and Q(SiO4 / 2 The molar ratio in units of ) and the molar and weight percentages of the above-mentioned alkenyl (e.g., vinyl) groups were measured.

[0074] GPC Number average molecular weight (M) of silicone-modified polyethers n The molecular weight was determined using GPC analysis. The chromatography system consisted of a Waters 2695 separation module equipped with a vacuum degasser and a Waters 2414 refractive index detector. Separation was performed using three Styragel® HR columns (300 mm × 7.8 mm) (molecular weight separation range 100 to 4,000,000), followed by a Styragel® Guard column (30 mm × 4.6 mm), where Styragel is a trademark of Waters Technologies Corporation. The analysis was performed using certified grade tetrahydrofuran (THF) flowing at 1.0 ml / min as the eluent, with both the column and detector heated to 35°C. A 1.0 wt% / v sample was prepared by weighing 0.050 g into a glass vial (8 mL) and diluting it with 5 mL of THF. The sample solution was filtered through a 0.45 μm polytetrafluoroethylene (PTFE) filter and then transferred to a glass autosampler vial. A 100 microliter (μL) injection volume was used, and data was collected for 37 minutes. Data acquisition and analysis were performed using Waters Empower GPC software. The average molecular weight was determined against a cubic calibration curve created using standard polystyrene with a molecular weight range of 474–1,270,000.

[0075] Volume resistivity (VR): A silicone composition was poured into a mold (20 mm × 6 mm × 0.4 mm (thickness)) on a glass slide and cured at 150°C for 2 hours to form a cured sample. The cured sample was left at room temperature for 12 hours before the VR test. The volume resistivity of the cured sample was measured according to GB / T1552-1995 using a 4-probe volume resistivity tester (ST2253) from Suzhou Jingge Electronic Co., Ltd. (China).

[0076] The as-cured sample on a glass slide is placed under a 4-probe VR tester, and the initial VR of the sample is measured. Initial The results were then presented. Next, the samples were placed in an oven and heat-aged at 125°C for a certain period (20-60 days), and then cooled to room temperature for more than 12 hours. The VR of the heat-aged samples was measured, and the VR Aging This was shown as VR. Variation The change in VR before and after thermal aging, as shown, is calculated based on the following formula. VR Variation =(VR Aging -VR Initial ) / VR Initial *100%

[0077] Median particle size of conductive filler Using a Beckman Coulter laser diffraction grain size analyzer (model LS13 320), 10 8 The median particle size of the filler, i.e., the D50 particle size, is determined by determining the volume-weighted particle size distribution of the particles.

[0078] complex viscosity All components of the silicone composition were mixed together. Within two hours, the complex viscosity of the resulting silicone composition was measured using a TA DHR-III rheometer (TA Instruments) between 25 parallel cross-hatch plates at room temperature, under a strain of 1%, and at an angular frequency of 0.1 radians / second (rad / s), using vibration frequency sweep and Cox-Merz transform. The silicone compositions were classified as follows based on the measured complex viscosity.

[0079] "Powdered" represents a viscosity of >550,000 Pa·s, "gum" represents a viscosity in the range of >350,000 to 550,000 Pa·s, "paste" represents a viscosity in the range of >10,000 to 350,000 Pa·s, and "viscosity" represents a viscosity in the range of 1,000 to 10,000 Pa·s.

[0080] Storage life The shelf life of a silicone composition is determined by first mixing all its components and then storing the resulting silicone composition at room temperature for three months. The appearance of the silicone composition before and after storage was observed and recorded. If no oily liquid is visible to the naked eye on the surface of the silicone composition after storage (i.e., no bleeding or glossy surface), the silicone composition is stable. Otherwise, if the silicone composition exhibits a glossy surface after storage, the silicone composition is not stable.

[0081] Silicone compositions of the present invention, Examples (IE) 1-22 and Comparative Examples (CE) 1-20. Preparation of Premix S-1: All components of Premix S-1 listed in Table 1-1 were added to a polypropylene (PP) bottle and mixed twice for 30 seconds at 3,000 revolutions per minute (rpm) using a dental mixer to obtain Premix S-1.

[0082] Premix S-2 (S-2) was prepared based on the components listed in Table 1-2, following the same procedure as the preparation of Premix S-1 described above.

[0083] Next, specific amounts of the as-prepared premix S-1 or premix S-2 were placed in separate bottles and mixed with the other components of the silicone composition shown in Tables 2-7 at 2,000 rpm for 1 minute under vacuum using a dental mixer to obtain the silicone composition. The viscosity and VR performance of the obtained silicone composition were evaluated according to the test method described above, and the results are shown in Tables 2-7. [Table 2] *Weight % refers to the weight percentage relative to the total weight of Premix S-1. [Table 3] *Weight % refers to the weight percentage relative to the total weight of Premix S-2.

[0084] As shown in Table 2, all of the IE1-4 silicone compositions exhibited the desired viscosity. In contrast, the CE1 silicone composition showed an undesirable high complex viscosity and appeared gum-like. The IE1-4 silicone compositions provided cured products that had much better conductivity, as indicated by the lower VR compared to CE1-5. In particular, the IE1-4 silicone compositions showed a 100-fold decrease in VR during curing compared to CE1, and a 1,000 g / mol M n The curing product (CE4) containing PPG showed a VR reduction of more than 50%. [Table 4] mΩcm represents milliohms-centimeters.

[0085] As shown in Table 3, the silicone compositions of IE2-4 during curing provided significantly less VR variation compared to composition CE1, which contained no polymer additives, or compositions CE3 and CE6-7, which contained P400PPG, PEG600, and SPE, respectively. [Table 5] NC non-conductive

[0086] As shown in Table 4, all IE5-10 silicone compositions exhibited the desired viscosity. In contrast, the CE8 silicone composition exhibited an undesirable high complex viscosity and appeared gum-like. The IE5 and 8 silicone compositions provided cured products made from them that had significantly better conductivity than those made from CE8, as indicated by a VR reduction of over 70% of the VR of the cured product made from CE8. The IE6 and 9 silicone compositions provided significantly better conductivity than that of CE9, as indicated by a VR reduction of over 80% of the VR of the cured product made from CE9. The IE7 and IE10 silicone compositions provided significantly better conductivity than that of CE10, as indicated by a VR reduction of over 99% of the VR of the cured product made from CE10. The IE5-10 silicone compositions also provided significantly better conductivity than those of CE11 and CE12 during curing. [Table 6]

[0087] As shown in Table 5, the IE9 silicone composition during curing provided significantly less VR variation compared to CE9, which contains no polymer additives, or CE14, which contains SPE. The IE11 and IE12 silicone compositions also provided significantly less VR variation during curing compared to CE13, which contains no polymer additives. [Table 7]

[0088] As shown in Table 6, all IE13-18 silicone compositions exhibited the desired viscosity. Furthermore, after storage at room temperature for 3 months, the CE16 silicone composition showed significant bleeding (i.e., a glossy surface), while no bleeding was observed in the silicone compositions with the same filler content (IE14 and IE17).

[0089] The silicone compositions IE13 and IE16 provided cured products with a VR reduction of over 75% compared to the cured product made from CE15. The silicone compositions IE14 and IE17 provided cured products with a VR reduction of over 50% compared to the cured product made from CE16. The silicone compositions IE15 and IE18 provided cured products with a VR reduction of over 99% compared to the cured product made from CE17. This indicates that the silicone compositions IE13 and IE16, IE14 and IE17, and IE15 and IE18 provided cured products with significantly better initial conductivity than those of CE15, CE16, and CE17, respectively. Furthermore, the silicone compositions IE13 and IE16 provided significantly less VR variation during curing than CE15, and IE16 provided even less VR variation than IE13. [Table 8] N / A - Not available

[0090] As shown in Table 7, all silicone compositions IE19-22 exhibited the desired viscosity. Furthermore, after storage at room temperature for 3 months, the CE19 silicone composition showed significant bleeding (i.e., a glossy surface), while no bleeding was observed in the silicone composition (IE20) with DF-163 at the same filler addition amount.

[0091] The silicone compositions of IE19 and IE22 resulted in a VR reduction exceeding 60% compared to CE18. The cured product manufactured from IE20 showed a VR reduction of 65% of the VR of the cured product made from CE19, and the cured product made from IE21 provided a VR reduction of 99% of the VR of the cured product made from CE20. This indicates that the silicone compositions of IE19 and 22, IE20, and IE21 provided cured products with much better initial conductivity compared to those of CE18, CE19, and CE20, respectively. Additionally, the silicone compositions of IE19 and IE22 provide much less VR variation upon curing than CE18, which indicates better retention of conductivity than CE18.

Table 9

[10] R M 3 SiO 1 / 2 Units and SiO 4 / 2 Essentially derived from units, each R M The silicone composition according to any one of the above [1] to [9], further comprising, independently, an alkyl or alkenyl polyorganosilicate resin, wherein the polyorganosilicate resin contains an average of 3 mol% to 20 mol% of alkenyl groups.

[11] The silicone composition according to any one of the above [1] to

[10] , further comprising an adhesion promoter.

[12] The silicone composition according to

[11] , wherein the adhesion promoter is selected from glycidoxypropyltrimethoxysilane, hydroxy-terminated, vinyl-functionalized polydimethylsiloxane, or a combination thereof.

[13] A process for preparing the silicone composition according to [1], comprising mixing the conductive filler, the polydiorganosiloxane polymer, the polyorganohydrogensiloxane, the hydrosilylation reaction catalyst, the polymer additive, and, if used, the hydrosilylation reaction inhibitor.

[14] A silicone adhesive comprising a cured product of the silicone composition described in any one of the above items [1] to

[12] .

Claims

1. A silicone composition, wherein, in weight ratio based on the total weight of the silicone composition, (A) 66% to 89% conductive filler, (B) A polydiorganosiloxane polymer of formula (I) in an amount of 5% to 32%, (R) １ ３ SiO １／２ ) ２ (R) １ ２ SiO ２／２ ) ｎ (I) In the formula, each R １ is independently a monovalent aliphatic hydrocarbon group, n ranges from 35 to 1,000, and the polydiorganosiloxane polymer contains an average of at least 2 alkenyl groups per molecule, the polydiorganosiloxane polymer of formula (I), and (C) A polyorganohydrogensiloxane of formula (II), (R ２ ３ Yes １／２ ) ２ (R ２ ２ Yes ２／２ ) ｍ (II) In the formula, each R ２ However, independently, each is a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, m is in the range of 5 to 200, and the polyorganohydrogensiloxane has an average of at least 3 silicon-bonded hydrogen atoms per molecule, and is a polyorganohydrogensiloxane of formula (II), (D) Hydrosilylation reaction catalyst, (E) A polymer additive having a number average molecular weight of more than 2,000 to 20,000 g / mol in an amount of 0.1% to 1.5%, selected from alcohol-initiated ethylene oxide and propylene oxide copolymer, (F) comprising 0-0.3% hydrosilylation reaction inhibitor, The alcohol-initiated ethylene oxide and propylene oxide copolymer has the structure of formula (III), (A) ｚ B(---) A is HO-(CHR ｐ - CHR ｑ -O) ｘ - (CH ２ -CH ２ -O) ｙ - represents x is 8 to 40, y is 1 to 20, R ｐ and R ｑ They differ, and hydrogen and -CH ３ A silicone composition in which z is selected from the above, z is 3 to 12, and B is a hydrocarbon group having 3 to 18 carbon atoms and having a valency of 3 to 12.

2. The silicone composition according to claim 1, wherein the alcohol-initiated ethylene oxide and propylene oxide copolymer contains 50% to 99% by weight of propylene oxide units based on the weight of the copolymer.

3. The silicone composition according to claim 1 or 2, wherein the alcohol-initiated ethylene oxide and propylene oxide copolymer has a molecular weight of 3,000 to 14,000 g / mol.

4. The silicone composition according to claim 1 or 2, wherein the conductive filler comprises particles consisting of silver or an alloy thereof, silver-coated nickel particles, silver-coated glass particles, silver-coated aluminum particles, silver-coated copper particles, or a mixture thereof.

5. In equation (I), n is between 35 and 500, and R １ The silicone composition according to claim 1 or 2, wherein at least 50 mol% of the monovalent aliphatic hydrocarbon group represented by is methyl.

6. The silicone composition according to claim 1 or 2, wherein the molar ratio of silicon-bonded hydrogen atoms in the polyorganohydrogensiloxane to alkenyl groups in all components of the silicone composition is 0.5 to 10.

7. R Ｍ ３ SiO １／２ Units and SiO ４／２ Essentially derived from units, each R Ｍ However, independently, it further comprises a polyorganosilicate resin which is alkyl or alkenyl, wherein the polyorganosilicate resin contains an average of 3 mol% to 20 mol% of alkenyl groups, and the R in the polyorganosilicate resin Ｍ ３ SiO １／２ Units (M units) and SiO ４／２ The silicone composition according to claim 1 or 2, wherein the total amount of units (Q units) is 98% by weight or more based on the total weight of the polyorganosilicate resin.

8. A process for preparing a silicone composition according to claim 1, comprising mixing the conductive filler, the polydiorganosiloxane polymer, the polyorganohydrogensiloxane, the hydrosilylation reaction catalyst, the polymer additive, and, if used, the hydrosilylation reaction inhibitor.

9. A silicone adhesive comprising a cured product of a silicone composition according to any one of claims 1 to 7.

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