CN116875270A - Ultralow-viscosity rapidly-curable low-temperature flexible organic silicon potting material, preparation method and application - Google Patents

Ultralow-viscosity rapidly-curable low-temperature flexible organic silicon potting material, preparation method and application Download PDF

Info

Publication number
CN116875270A
CN116875270A CN202310725809.XA CN202310725809A CN116875270A CN 116875270 A CN116875270 A CN 116875270A CN 202310725809 A CN202310725809 A CN 202310725809A CN 116875270 A CN116875270 A CN 116875270A
Authority
CN
China
Prior art keywords
vinyl
silicone oil
viscosity
silicone
component
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202310725809.XA
Other languages
Chinese (zh)
Inventor
雷卫华
陈茂斌
李玉全
花成
余凤湄
张亚玲
刘小兵
张倩
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Institute of Chemical Material of CAEP
Original Assignee
Institute of Chemical Material of CAEP
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Institute of Chemical Material of CAEP filed Critical Institute of Chemical Material of CAEP
Priority to CN202310725809.XA priority Critical patent/CN116875270A/en
Publication of CN116875270A publication Critical patent/CN116875270A/en
Pending legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J183/00—Adhesives based on macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon, with or without sulfur, nitrogen, oxygen, or carbon only; Adhesives based on derivatives of such polymers
    • C09J183/04—Polysiloxanes
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J11/00—Features of adhesives not provided for in group C09J9/00, e.g. additives
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J11/00—Features of adhesives not provided for in group C09J9/00, e.g. additives
    • C09J11/02—Non-macromolecular additives
    • C09J11/04—Non-macromolecular additives inorganic
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L2205/00—Polymer mixtures characterised by other features
    • C08L2205/02—Polymer mixtures characterised by other features containing two or more polymers of the same C08L -group
    • C08L2205/025—Polymer mixtures characterised by other features containing two or more polymers of the same C08L -group containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L2205/00—Polymer mixtures characterised by other features
    • C08L2205/03—Polymer mixtures characterised by other features containing three or more polymers in a blend
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L2205/00—Polymer mixtures characterised by other features
    • C08L2205/03—Polymer mixtures characterised by other features containing three or more polymers in a blend
    • C08L2205/035—Polymer mixtures characterised by other features containing three or more polymers in a blend containing four or more polymers in a blend

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Inorganic Chemistry (AREA)
  • Compositions Of Macromolecular Compounds (AREA)

Abstract

The invention discloses an ultralow-viscosity rapidly-curable low-temperature flexible organic silicon potting material, a preparation method and application thereof, wherein the low-temperature flexible organic silicon potting material comprises the following components: vinyl silicone oil, inert (silicon) oil, cross-linking agent, inhibitor, hydrophobic silicon dioxide and platinum (rhodium) catalyst. The vinyl silicone oil, inert (silicon) oil, cross-linking agent, inhibitor, platinum catalyst and other components are respectively and uniformly mixed and dispersed at high speed, and are hermetically packaged, so that the ultralow-viscosity low-temperature flexible liquid organosilicon elastomer material provided by the invention is obtained, and has the advantages of low viscosity, good curing effect, softness, elasticity, good appearance, low-temperature flexibility and high-temperature stability.

Description

Ultralow-viscosity rapidly-curable low-temperature flexible organic silicon potting material, preparation method and application
Technical Field
The invention relates to an ultralow-viscosity rapidly-curable low-temperature flexible organic silicon encapsulating material and a preparation method and application thereof, in particular to a flexible liquid organic silicon encapsulating material with complex gap rapid encapsulation and temperature sensitive part protection and a preparation method thereof.
Background
The liquid organic silicon encapsulating material has good electrical property, weather resistance and heat aging resistance, water resistance and ozone resistance, low density, flexibility and rebound resilience, can encapsulate various gap structures and part components, has good filling property, can endow heat conduction and flame retardance and other functions, is widely applied to fields of machinery, aerospace, transportation, construction, electronic appliances and the like, and is applied to new fields of wind power motors, high-power electric elements, LED elements, solar photovoltaic components and the like in recent years.
The inventor finds that (1) the common organosilicon potting adhesive on the market is generally higher (usually 1-5 Pas) and has long curing time (more than 10 h), so that the requirements of potting with complex gaps and quick curing are difficult to meet; (2) The liquid organosilicon material with low viscosity (20-200 mPa.s) has better fluidity, but has high functional group content, higher curing exotherm (the organosilicon with 20mPa.s heats up to 20 ℃ when curing), obviously hardens after curing, has insufficient flexibility, and is difficult to meet the requirements of flexible protection required by impact vibration sensitive parts and low-temperature impact required by temperature sensitive parts; (3) Common organosilicon pouring sealants have poor toughness at low temperature, for example, high-viscosity polydimethylsiloxane is crystallized and hardened at-42 ℃ after being solidified, and the common organosilicon pouring sealants are not suitable for being used in a low-temperature environment.
The inventor conducts research on the ultralow-viscosity low-temperature-flexibility low-curing exothermic liquid organic silicon encapsulating material to obtain the practical ultralow-viscosity rapidly-curable low-temperature-flexibility organic silicon encapsulating material and the preparation method, and can meet the use requirements of impact vibration, temperature-sensitive part protection and wide temperature range.
Disclosure of Invention
Problems to be solved by the invention
The present invention has been made in view of the above-mentioned facts, and an object of the present invention is to provide a low-temperature flexible silicone potting material which is capable of being cured quickly with ultra-low viscosity, which can meet the requirements of filling various complex gaps and low curing exotherm, low-temperature flexibility, can realize quick curing, and can meet the requirements of protection of impact, vibration and temperature sensitive parts and the requirements of wide-temperature-range use.
Means for solving the problems
As a result of intensive studies to achieve the above object, the present inventors have found that a liquid silicone potting material having excellent complex gap potting properties, low temperature impact (low heat release), excellent vibration protection properties, adjustable curing speed, rapid curing, good low temperature flexibility, and excellent high temperature performance can be obtained by compounding vinyl silicone oil, extremely low viscosity inert (silicone) oil, active hydrogen-containing silicone oil (crosslinking agent), and platinum (rhodium) catalyst.
Accordingly, the present invention provides an ultra-low viscosity, rapidly curable, low temperature flexible liquid silicone potting material comprising the following components:
the viscosity of the mixture of vinyl silicone oil and inert (silicone) oil is not more than 300mpa.s.
Alternatively, the viscosity of the mixture of vinyl silicone oil and inert (silicone) oil is not more than 100mpa.s.
Alternatively, the viscosity of the mixture of vinyl silicone oil and inert (silicone) oil is not more than 200mpa.s.
The component A is at least one vinyl silicone oil selected from vinyl-terminated dimethyl silicone oil, vinyl-terminated diethyl silicone oil, vinyl-terminated dimethyl diphenyl silicone oil, vinyl-terminated dimethyl phenyl silicone oil, vinyl-terminated trifluoropropyl silicone oil and liquid MV (D) Q vinyl silicone resin, wherein the vinyl silicone oil contains at least 2 vinyl functional groups connected with silicon atoms, and the viscosity of the vinyl silicone oil is not more than 10000 mPa.s and not less than 150 mPa.s; the amount of the component having a viscosity of 1000 mPas or more in the vinyl silicone oil is 50 parts by mass or less based on 100 parts by mass of the component A.
Alternatively, the vinyl silicone oil may contain 30 parts by mass or less of a component having a viscosity of 1000 mPas or more based on 100 parts by mass of the component A.
The inert (silicon) oil in the component B is at least one selected from dimethyl silicone oil, diethyl silicone oil, dimethyl monophenyl silicone oil, dimethyl diphenyl silicone oil, trifluoropropyl silicone oil, liquid paraffin (oil), di (iso) octyl sebacate and di (iso) octyl phthalate, and the viscosity at 25 ℃ is not higher than 50 mPa.s.
The single molecule of the hydrogen-containing silicone oil contains at least two hydrogen atoms connected with silicon atoms, and the content of the hydrogen atoms connected with the silicon atoms is not less than 0.15%.
The inhibitor D Cheng Fensuo is at least one selected from the group consisting of 1-ethynyl cyclohexanol, 3-methyl-1-pentyn-3-ol, 3, 5-dimethyl-1-hexyn-3-ol, 3-methyl-3-trimethylsiloxy-1-butyne, trimethyl (3- ((trimethylsilyloxy) prop-1-yn-1-yl) silane, polyvinyl siloxane, tetramethyl tetra-vinyl cyclotetrasiloxane telomer, tetramethyl di-vinyl disiloxane.
The component E is a platinum-rhodium catalyst selected from one of a platinum catalyst and a rhodium catalyst, wherein the platinum catalyst is a platinum complex formed by the reaction of chloroplatinic acid, alkene, alcohol, alkyne and triphenylphosphine, and the rhodium catalyst is a complex of triphenylphosphine and rhodium; the olefin is selected from one of tetramethyl divinyl disiloxane, tetramethyl tetravinyl cyclodisiloxane, 1, 3-divinyl-1, 3 diphenyl-dimethyl disiloxane, propylene, vinyl alkoxy silane, vinyl siloxane, 1-hydroxy, 3-vinyl-tetramethyl disiloxane and vinyl cyclosiloxane; the alcohol is ethanol or isopropanol, and the alkyne is acetylene.
The BET specific surface area of the hydrophobic silica of the component F is 50-300 m 2 And/g, the carbon content is 2-6%.
The percentages in the present invention refer to mass percentages unless otherwise specified.
The invention also provides a preparation method of the ultralow-viscosity rapidly-curable low-temperature flexible liquid organic silicon encapsulating material, which comprises the following steps:
a. uniformly mixing vinyl silicone oil, inert (silicon) oil and hydrophobic silicon dioxide to obtain base adhesive;
b. then mixing the base adhesive with hydrogen silicone oil and inhibitor, and dispersing uniformly;
c. and adding a platinum-rhodium catalyst, and rapidly stirring and mixing to obtain the flexible liquid organosilicon elastic potting material.
When the ultralow-viscosity rapidly-curable low-temperature flexible liquid organic silicon encapsulating material is applied, the encapsulating material is encapsulated in various gap structures of equipment or components, cured and then the equipment or components are placed at an ambient temperature of more than-50 ℃ for use.
The curing environmental conditions of the liquid organosilicon potting material of the invention are not particularly limited, and the curing environmental conditions of the liquid organosilicon potting material can be at room temperature or higher temperature, or at a temperature lower than room temperature such as 0 ℃ and below, so long as the normal use and curing environmental conditions of the potting material are not affected. Curing is typically performed at ambient temperature, which reduces the temperature control process.
Alternatively, the device or assembly is used at room temperature.
Alternatively, the device or assembly is used at 0 to-50 ℃.
Alternatively, the apparatus or assembly is used at a temperature of-30℃to-50 ℃. The present invention will be described in more detail below.
Component A-
The vinyl silicone oil of the component A is at least one selected from vinyl-terminated dimethyl silicone oil, vinyl-terminated diethyl silicone oil, vinyl-terminated dimethyl diphenyl silicone oil, vinyl-terminated dimethyl phenyl silicone oil, vinyl-terminated trifluoro propyl silicone oil, and liquid MV (D) Q vinyl silicone resin, wherein the vinyl silicone oil contains at least 2 vinyl functional groups connected with silicon atoms, and the viscosity of the vinyl silicone oil is not more than 10000 mPa.s and not less than 150 mPa.s. The vinyl silicone oil contains not more than 50 parts by mass of a component having a viscosity of more than 1000 mPas per 100 parts by mass of the component (A).
The vinyl-terminated silicone oil is polyorganosiloxane with at least 2 vinyl functional groups directly connected with silicon atoms per molecule, and the structural formula is shown in formula (I).
Wherein R is 1 Represents identical or different monovalent hydrocarbon radicals, R 2 Representing a functional group.
In the structural formula (I), R 1 Examples of monovalent hydrocarbon groups which may be the same or different include methyl, ethyl, phenyl trifluoropropyl, and the like. Monovalent hydrocarbon radicals R of vinyl silicone oils 1 Among these, methyl groups and phenyl groups are preferable, and the ratio of methyl groups in the total number of R groups is preferably 80 to 99.99mo1%, more preferably 90 to 99.99mo1%. The terminal group of the organopolysiloxane is dimethylvinylsiloxane or the like which can participate in the crosslinking reaction. The viscosity average polymerization degree of the vinyl-terminated silicone oil is not more than 880, preferably 100 to 400, more preferably 120 to 300.
The liquid MV (D) Q silicone is composed of monofunctional units M [ Vi (CH) 3 ) 2 SiO 0.5 -]Difunctional units (D) [ - (CH) 3 ) 2 SiO-]And tetrafunctional units (Q) [ -SiO 2 -]The polysiloxane compound with structural composition is liquid polyorganosiloxane with vinyl and high branched stereo (nonlinear) structure and with Si-O bond as skeleton, and includes MVDQ silicone resin and MQ silicone resin. The content of D in the MVDQ silicone resin is between 0 and 20 percent. MVDQ silicone resins are typically prepared by acid catalyzed hydrolytic polycondensation, base catalyzed hydrolytic polycondensation, and metal salt catalyzed polycondensation. The MQ silicon resin is mainly synthesized by adopting a water glass method and an ethyl orthosilicate method. In the preparation process of MV (D) Q silicone resin, the following steps are conductedBy introducing comonomers with different functional group side groups, MV (D) Q silicone resin containing different groups such as alkyl, phenyl, vinyl and the like can be prepared, so that the MV (D) Q silicone resin is endowed with specific properties.
The liquid MV (D) Q silicone resin can be synthesized by using difunctional chain-linked polysiloxanes such as hydroxyl-terminated polydimethylsiloxane and vinyl-terminated polydimethylsiloxane and trifunctional chain-linked polysiloxanes such as phenyl trimethoxy silane, methyl triethoxy silane and allyl triethoxy silane as raw materials, so as to synthesize the solvent-free organosilicon resin with various characteristics and flowing at room temperature.
The liquid vinyl MQ and MVDQ silicones have MQ values between 0.6 and 1.5, preferably between 0.8 and 1.2; vinyl content is between 0.3-5%, preferably 0.5-3%; the viscosity is not more than 10000 mPas, not less than 1000 mPas, and preferably in the range of 3000 to 7000 mPas. As long as the MQ value of the liquid vinyl MQ resin is in the corresponding range, good dispersion and proper reinforcing effect of the vinyl silicone oil at the end can be obtained; the vinyl content within this range ensures proper reinforcement and good low-temperature flexibility.
The vinyl silicone oil can adopt a single molecular chain structure or a mixture of two or more organopolysiloxanes with different molecular chain structures or unequal viscosity average polymerization degrees and liquid vinyl M (D) Q silicone resin, preferably 2-3 types; the vinyl silicone oil having a viscosity of more than 1000mPa.s is used in an amount of not more than 50 parts by mass per 100 parts by mass of the vinyl silicone oil. Within this range, the organopolysiloxane of component (A) has suitable flowability, good processability and suitable mechanical properties.
Component B-
The inert (silicon) oil of the component B is at least one selected from trifluoromethyl silicone oil, diethyl silicone oil, dimethyl monophenyl silicone oil, dimethyl diphenyl silicone oil, liquid paraffin (oil), di (iso) octyl sebacate and di (iso) octyl phthalate, and the viscosity is not more than 50 mPas (25 ℃). The dimethicone includes, but is not limited to, terminal methyl dimethicone.
Wherein the inert silicone oil is characterized in that the molecular chain is linear, contains one to three kinds of side groups such as methyl, ethyl or phenyl and trifluoromethyl, has a molecular weight of less than 10000 and a viscosity of not more than 50 mPas (25 ℃); is not reactive at room temperature. The inert (silicon) oil can be one or a combination of several molecular chains, or can be a combination of chemical structures but different viscosities.
The amount of the component B to be added is preferably 60 to 120 parts by mass, more preferably 70 to 90 parts by mass, per 100 parts by mass of the component A, and particularly preferably no significant bleeding of the liquid from the surface after curing. Wherein the amount of the liquid paraffin (oil), di (iso) octyl phthalate, di (iso) octyl sebacate is preferably not more than 50 parts by mass. As long as the amount of component B is within this range, the viscosity, processability and flexibility, low temperature elasticity, etc. properties of the liquid silicone potting adhesive can be brought to acceptable levels.
Component C-
The component C hydrogen-containing silicone oil (crosslinking agent) is characterized in that a single molecule contains not less than two hydrogen atoms bonded to silicon atoms, and the content of the hydrogen atoms bonded to silicon atoms is not less than 0.15%.
The structural formula of the hydrogen-containing silicone oil is shown as formula II:
H c R 3-c Si-(SiHRO) a -(SiR 2 O) b -SiR 3-c H c (II)
wherein R represents the same or different monovalent hydrocarbon groups, a and b are the degrees of polymerization of different units, c is the number of end group functional groups, and c is a positive integer of 0 or less than 3.
In the structural formula (II), R represents the same or different monovalent hydrocarbon groups, and examples of R include methyl, ethyl, and phenyl groups. As shown in formula II, the active hydrogen may be located on a side group or end group of the crosslinker molecule, or both.
The hydrogen content of the hydrogen-containing silicone oil (in terms of hydrogen atoms directly bonded to silicon atoms) is preferably 0.2 to 1.6%, and more preferably 0.3 to 1.5%.
The hydrogen-containing silicone oil may employ a single molecular chain structure, or a mixture of two or more organopolysiloxanes having different molecular chain structures or differing in viscosity average degree of polymerization, and its actual components are combined to satisfy the time and effect required for curing.
The amount of component C to be added is preferably 10 to 35 parts by mass, more preferably 15 to 30 parts by mass, per 100 parts by mass of component A. As long as the amount of component C is within this range, the fluidity, curing speed, workability, and low-temperature flexibility, elasticity, etc. properties of the liquid silicone potting adhesive can be brought to acceptable levels.
Component D-
The inhibitor of component D is at least one selected from 3, 3-dimethyl-pentynol, 1-ethynyl-cyclohexanol, 3-methyl-1-butyn-3-ol, 3-methyl-1-pentyn-3-ol, 3, 5-dimethyl-1-hexyn-3-ol, tetramethyl-tetravinyl-cyclotetrasiloxane telomer, and tetramethyl-divinyl disiloxane. Tetramethyl tetravinyl cyclotetrasiloxane telomers such as R- (MeViSiO-) n R, wherein n=8 to 16, and the terminal group R may be exemplified by trimethylsiloxy, trivinylsiloxy, vinyldimethylsiloxy, etc.
Component D is preferably 1-ethynyl cyclohexanol, polyvinyl siloxane, polyvinyl cyclosiloxane or the like.
The amount of component D to be added is preferably 0 to 0.4 parts by mass, more preferably 0.005 to 0.2 parts by mass, still more preferably 0.01 to 0.1 part by mass, per 100 parts by mass of the vinyl silicone oil at the end of component A. As long as the amount of component D is within this range, the curing speed, processability and elasticity of the liquid silicone potting adhesive can reach acceptable levels.
Component E-
The catalyst of the component E is a platinum (rhodium) catalyst with catalytic activity on hydrosilylation, the platinum catalyst is a platinum complex formed by the reaction of chloroplatinic acid (hydration) and alkene, alcohol, alkyne and triphenylphosphine, and the rhodium catalyst is a complex of triphenylphosphine and rhodium. The olefin comprises tetramethyl divinyl disiloxane, tetramethyl tetravinyl cyclodisiloxane, 1, 3-divinyl-1, 3 diphenyl-dimethyl disiloxane, propylene and derivatives thereof, vinyl silane, vinyl siloxane, 1-hydroxy, 3-vinyl-tetramethyl disiloxane and vinyl cyclosiloxane; the alcohol is ethanol or isopropanolThe alkyne is acetylene. Specifically, platinum catalysts such as complexes of platinum metal with olefinic compounds such as Pt (0) complexes (PPh 3 ) 2 Pt-(CH 2 ＝CH 2 ) Chloroplatinic acid (H) 2 PtCl 6 ·H 2 Isopropanol solution of O) (carrier catalyst), ethanol solution of chloroplatinic acid, platinum-alkyne based complexes such as bis (alkynyl) bis (triphenylphosphine) platinum complex, bis (alkynyl) (cyclodienyl) platinum complex, karstedt catalyst ([ (CH) 2 ＝CHSiMe 2 ) 2 O] 2 Pt)——H 2 PtCl 6 With tetramethyl divinyl siloxane (DVDM) and NaHCO 3 Reaction product of (A) Willing catalyst-H 2 PtCl 6 The acid product was washed with water after reaction with tetramethyl divinyl siloxane. The olefinic compound is selected from, but not limited to, tetramethyl divinyl disiloxane, tetramethyl tetravinyl cyclotetrasiloxane, 1, 3-divinyl-1, 3 diphenyl-dimethyl disiloxane, 1-hydroxy-3-vinyl-tetramethyl disiloxane, propylene, vinyl trimethoxysilane, vinyl triethoxysilane, gamma- (methacryloyloxy) propyl trimethoxysilane, and the like. The triphenylphosphine complex of platinum and rhodium comprises a complex formed by triorganophosphaplatin and alkyne-based compound, pt-dichloro bis (triphenylphosphine) (Pt (PPh) 3 ) 2 Cl 2 ) Rh-dichloro-bis (triphenylphosphine) (Rh (PPh) 3 )Cl 2 Wilkinson catalyst), tris (triphenylphosphine) rhodium chloride complex.
Component E is preferably a platinum-tetramethyl-divinyl-disiloxane complex (CH 2 ＝CHSiMe 2 ) 2 Pt, platinum-tetramethyl-tetravinyl cyclotetrasiloxane complex, platinum-1-hydroxy-3-vinyl-tetramethyl disiloxane complex, (PPh) 3 ) 2 Pt(CH 2 ＝CH 2 ) And chloroplatinic acid (H) 2 PtCl 6 ·H 2 O) (carrier catalyst).
The purity or concentration of the component E is not obviously limited, the noble metal content is 1000ppm or 5000ppm, even 18% higher, as long as the addition amount of the component E meets the requirement of forming in a defined concentration range according to the mass of Pt or rhodium, so that the required pouring sealant can flow to fill gaps and can be cured in time; the addition mode of the component E is not obviously limited, and the component E can be directly added, can be diluted into a lower concentration and then added, and the material used for dilution is not particularly limited, can be vinyl silicone oil or inert (silicon) oil, and can be other materials which can be uniformly dispersed and do not affect the functionality.
The complex of the platinum catalyst can adopt a single ligand structure or a platinum mixture of two ligands and even a plurality of organic ligands, and the actual structure depends on the time and effect required by the pouring sealant. For example, VM-23 platinum complex produced by Zhejiang qu orange building organic silicon Co., ltd, the main component of which is [ (CH) 2 ＝CHSiMe 2 ) 2 O] 2 Pt and [ (CH) 2 ＝CHSiMe 2 )O]Pt[CH 2 ＝CHSiMe 2 OSiMe 2 OH]Pt mass fraction is 1000-5000 ppm.
The addition amount of the component E is calculated by compounding 0.3-100ppm (ppm is abbreviated as parts per million by mass of Pt) of the components A-F, and curing time is required to meet actual requirements, so long as the amount of the component E is within the range, the processability and the physical and mechanical properties of the liquid organosilicon pouring sealant can reach acceptable levels. Since the method based on the mass of Pt in the active ingredient is adopted, even if the purity or concentration supplied from the supplier of the component E is different or the habit of the user is different, the amount of the active ingredient added is the same, which ensures that the same molding effect is obtained.
Component F-
The component F hydrophobic silica nanoparticles are used for ensuring that a liquid organosilicon potting material with proper rheological properties is obtained. The average particle size of the hydrophobic silica nanoparticles is less than 2 microns; at least one of the highly hydrophobic silica nanoparticles of the F component, wherein the specific surface area (BET method) of the nanoparticle is 100-300 m 2 Between/g.
In order to ensure proper rheological property, the specific surface area of the hydrophobic silica nano particles is 1O-400m 2 Between/g, preferably 100 to 300m 2 Preferably 130 to 240m 2 And/g. Examples of hydrophobic silica nanoparticles include gasPhase silica (dry silica, fumed silica), precipitated silica, sol-gel silica particles. The hydrophobic silica particles may be a single material or a combination of two or more different materials.
In order to disperse the hydrophobic silica particles in the component A, B, a highly efficient dispersing agent that can react with the surface of the silica particles, such as hexamethyldisilazane, hexamethylcyclotrisilazane, polysilazane, or the like, may be added. The amount of the dispersant to be added is preferably 1 to 10 parts by mass, more preferably 2 to 5 parts by mass, per 100 parts by mass of the silica particles.
The amount of the highly hydrophobic silica nanoparticles to be added is preferably 0 to 15 parts by mass, more preferably 5 to 10 parts by mass, per 100 parts by mass of the component A composition. As long as the amount of highly hydrophobic silica nanoparticles is within this range, the processability and physical mechanical properties of the liquid silicone potting material can reach acceptable levels.
Mixing of the hydrophobic silica nanoparticles of component A, B and the like and component F can be carried out by mixing the hydrophobic silica nanoparticles with the above-mentioned preferable dispersant using a machine such as a planetary mixer or a mechanical mixer, and vacuum treatment can be carried out at a high temperature to remove moisture and hydroxyl groups from the mixture.
Other ingredients-
The present invention may further comprise a conductivity imparting agent such as acetylene black, conductive carbon black, carbon nanotubes, graphene, etc., including silane or titanate coupling agents, etc., having vinyl and acryloxy groups, epoxy groups, alkoxy groups, etc. as functional groups to enhance adhesion, and may further be coated with a primer or release agent, etc., before use.
Preparation method-
The preparation method of the organic silicon encapsulating material is characterized by mainly comprising the following steps of:
a. by using a mechanical stirrer, a planetary stirrer or the like, the liquid vinyl silicone oil, the inert (silicone) oil and the specific surface area (BET method) are not less than 10m 2 Uniformly mixing/g hydrophobic nano silicon dioxide particles, removing water or other volatile gases carried by the silicon dioxide particles by high-temperature treatment, and coolingAnd obtaining the pouring sealant base adhesive after cooling. No high temperature treatment is required when no hydrophobic silica particles are added.
b. And adding hydrogen silicone oil, inhibitor and the like into the pouring sealant base adhesive, and thoroughly and uniformly mixing.
c. Uniformly mixing vinyl silicone oil, dimethyl silicone oil, a catalyst (inhibitor) and the like, adding the mixture according to a proper proportion, and rapidly mixing the mixture to obtain the ultralow-viscosity flexible liquid organic silicon potting material; the mixed solution is quickly poured into a container or a gap to be filled and sealed, and solidified under the action of proper temperature and time.
All the components are quickly, uniformly and thoroughly mixed and dispersed before encapsulation by adopting a mechanical stirrer, a planetary stirrer or a reaction extrusion mixer (RIM) and a static mixer, and the mixed solution is quickly poured into a container, so that the liquid organosilicon encapsulating material can be completely solidified under the action of proper temperature and time.
The construction mode is not particularly limited, and no matter extrusion, casting or mould pressing can be carried out, the encapsulating structure with uniform structure and good elasticity can be obtained, and the forming effect is stable and the repeatability is good.
The packaging, construction or curing modes of the liquid organic silicon encapsulating material are not particularly limited, the packaging is of two components, three components and the like, the liquid organic silicon encapsulating material is suitable for on-site use, the construction is of liquid casting, injection or injection molding, extrusion and the like, and casting, injection molding and the like are preferred. The pressure condition for molding the liquid organic silicon potting material is not particularly limited, and the molding can be carried out either by pressureless free filling or pressurized potting, preferably, the molding is closed after the pressureless potting is carried out to a specified shape so as to maintain the required shape, and the molding is carried out only by self-filling the potting composition without additional pressure.
According to the invention, the low-temperature flexible liquid organic silicon encapsulating material with ultralow viscosity and quick solidification can be obtained, and the organic silicon encapsulating material with good solidification effect, softness, elasticity, good appearance, low-temperature flexibility and high-temperature stability can be obtained no matter the pouring, injection and casting molding methods are used.
The use environmental condition of the liquid organic silicon encapsulating material after solidification is not particularly limited, the lowest temperature is preferably-50 ℃, the highest temperature is preferably 250 ℃ and preferably not more than 180 ℃, as long as the liquid organic silicon encapsulating material keeps flexibility at low temperature and the degree of decomposition of the liquid organic silicon encapsulating material at high temperature does not influence the use environmental condition of encapsulated equipment.
Detailed Description
The present invention will be described in further detail with reference to the following examples in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
[ example 1 ]
18.2 parts of alpha, omega-terminal vinyl polydimethylsiloxane (colorless transparent flow liquid, viscosity 1000 mPas, polymerization degree 390, manufactured by orange organosilicon Co., ltd., zhejiang), 81.8 parts of alpha, omega-terminal vinyl polydimethylsiloxane (colorless transparent flow liquid, viscosity 500 mPas, polymerization degree 240) and 81.8 parts of simethicone (colorless transparent flow liquid, viscosity 20 mPas) were added to a kneader (or other mixing apparatus) and mixed rapidly and uniformly, 9.1 parts of BET specific surface area 150m were added 2 Hydrophobic fumed silica (manufactured by Beijing physicochemical institute of China academy of sciences), rapidly mixing (or kneading) uniformly, vacuumizing at 150deg.C, removing small molecules such as water, and cooling.
Then, 8 parts of liquid hydrogen-containing silicone oil (hydrogen content 0.5%, manufactured by Zhejiang Rumex organic silicon Co., ltd.) and 0.005 part of 1-ethynyl-cyclohexanol (commercially available, purity not less than 96%) were added, and after mixing uniformly at room temperature, 0.18 part of platinum catalyst (VM-23 platinum complex, pt content 5000ppm, manufactured by Zhejiang Rumex organic silicon Co., ltd.) was added, wherein the Pt catalyst was 4.5ppm by mass based on Pt, and the mixture was rapidly mixed in a beaker at room temperature for 4 minutes with a mechanical stirrer at a rotation speed of about 650rpm, and the mixture was uniformly mixed.
And (3) pouring the uniformly mixed materials into a container or a gap to be filled and sealed rapidly, and obtaining the fully-cured liquid organic silicon filling and sealing material with good surface structure after a period of time at the ambient temperature.
The following mixtures were tested for rotational viscosity at 25℃according to the method of GB/T10247-2016: (1) A homogeneous mixture of component A (vinyl silicone oil) and component B (inert (silicone) oil), and (2) a fully component homogeneous mixture of components (A) - (F). The cured liquid organic silicon encapsulating material is tested for Shore AO hardness (C type) of an encapsulating sample according to GB/T531-1999, a temperature change value during curing of 1000g of encapsulating is tested by adopting a thermometer, the cured sample is frozen at-50 ℃ for 3 hours to feel low-temperature flexibility, is treated at 180-200 ℃ for 3-5 hours, the thermal weight loss rate is tested, and the appearance change is observed to characterize the heat resistance.
[ example 2 ]
27.3 parts of alpha, omega-terminal vinyl polydimethylsiloxane (colorless transparent flow liquid, viscosity 1000 mPas, degree of polymerization 390, volatile 1.0%, manufactured by orange silicone Co., ltd.) 54.5 parts of alpha, omega-terminal vinyl polydimethylsiloxane (colorless transparent flow liquid, viscosity 200 mPas, degree of polymerization 130), 18.2 parts of alpha, omega-terminal vinyl polydimethylsiloxane (colorless transparent flow liquid, viscosity 500 mPas, degree of polymerization 240), 54.5 parts of terminal methyl polydimethylsiloxane (colorless transparent flow liquid, viscosity 20 mPas), 27.3 parts of liquid paraffin (colorless transparent flow liquid, viscosity 25 mPas), 8.0 parts of liquid hydrogen-containing silicone oil (hydrogen content 0.5%, manufactured by Zhejiang silicone materials Co., ltd.), 0.005 parts of 1-ethynyl-cyclohexanol (commercially available, purity not less than 96%) were mixed uniformly with a mechanical stirrer at room temperature, and then 0.17 parts of platinum catalyst (VM-23 ppm, 5000 ppm) was added and mixed rapidly.
And (3) pouring the uniformly mixed materials into a container rapidly, and obtaining the fully cured and flexible organic silicon pouring sealant material after a certain time at the ambient temperature.
[ example 3 ]
9.1 parts of alpha, omega-terminal vinyl polydimethylsiloxane (colorless transparent flow liquid, viscosity 1000mPa.s, degree of polymerization 390, manufactured by orange organic silicon Co., ltd.) 9.1 parts of alpha, omega-terminal vinyl polydimethylsiloxane (colorless transparent flow liquid, viscosity 500 mPa.s, degree of polymerization 240), 81.8 parts of alpha, omega-terminal vinyl polydimethylsiloxane (colorless transparent flow liquid)Body, viscosity 200 mPas, degree of polymerization 130), 90 parts of terminal methyl polydimethylsiloxane (colorless transparent flow liquid, viscosity 20 mPas), 18.2 parts of BET specific surface area 150m 2 Hydrophobic fumed silica (manufactured by Beijing physicochemical institute of China sciences) per gram, adding into kneader, kneading, vacuumizing at 150deg.C, removing small molecules such as water, and cooling.
Then, 10.4 parts of liquid hydrogen-containing silicone oil (hydrogen content: 0.5%, manufactured by Zhejiang Runhua silicone Co., ltd.) and 0.005 parts of 1-ethynyl-cyclohexanol (commercially available, purity: not less than 96%) were added, and after mixing at room temperature, 0.20 parts of platinum catalyst (VM-23 platinum complex catalyst) was added, followed by molding by potting as in example 1.
[ example 4 ]
50 parts of alpha, omega-terminal vinyl polydimethylsiloxane (colorless transparent flow liquid, viscosity 200 mPas, polymerization degree 130), 50 parts of liquid MVDQ silicone resin (colorless transparent flow liquid, viscosity 7000 mPas, vi content 1.2%, MQ value 0.8), 100 parts of simethicone (colorless transparent flow liquid, viscosity 20 mPas), 8 parts of liquid hydrogen silicone oil (hydrogen content 0.5%, manufactured by Zhejiang Rumex Silicone Co., ltd.) were mixed uniformly at room temperature, and then 0.19 parts of platinum catalyst (VM-23 platinum complex) was added thereto, and the mixture was molded by potting as in example 2, and the relevant properties were measured in the same manner as in example 1.
[ comparative example 1 ]
100 parts of alpha, omega-terminal vinyl polydimethylsiloxane (colorless transparent flow liquid, viscosity 100mPa.s, degree of polymerization 80, manufactured by Zhejiang Rumex Silicone New Co., ltd.) were reacted with 25 parts of BET specific surface area 150m 2 Adding hydrophobic fumed silica (manufactured by Beijing physical and chemical research institute of Chinese sciences) per gram into a kneader, kneading, vacuumizing at 150deg.C to remove small molecules, cooling, adding 15 parts of liquid hydrogen-containing silicone oil (hydrogen content 0.5%, manufactured by Zhejiang Rumex organosilicon New material Co., ltd.), 0.02 part of 1-ethynyl-cyclohexanol (commercially available with purity not less than 96%), mixing at room temperature, adding 0.10 part of platinum catalyst (VM-23, platinum complex catalyst) to obtain flowing liquid gel with good fluidity, rapidly pouring the mixed material into a container, and standing in environmentAfter being sufficiently cured at temperature, the silicone potting material was obtained, and the related test was conducted as in example 1.
[ comparative example 2 ]
100 parts of alpha, omega-terminal vinyl polydimethylsiloxane (colorless transparent flow liquid, viscosity 1000mPa.s, degree of polymerization 390, volatile 1.0%, manufactured by Zhejiang orange silicone Co., ltd.) were reacted with 10 parts of BET specific surface area 150m 2 After per gram of the highly hydrophobic fumed silica (manufactured by Beijing physicochemical institute of China) 6.5 parts of liquid hydrogen-containing silicone oil (hydrogen content 0.5%, manufactured by Zhejiang Rumex silicone New Material Co., ltd.), 0.015 part of 1-ethynyl-cyclohexanol (commercially available, purity not less than 96%) was uniformly mixed at room temperature, 0.07 part of platinum catalyst (VM-23, platinum complex catalyst) was further added, and the uniformly mixed material was rapidly poured into a container, and a silicone potting material which was sufficiently cured and had good fluidity but excellent filling property was obtained at ambient temperature, and the relevant test was conducted as in example 1.
Table 1 results of examples, comparative examples, raw materials and performance tests
As can be seen from Table 1, comparative example 1 has problems of high heat release for curing, large temperature rise for curing (-20 ℃) and high hardness, which are significantly hard at-50 ℃ and poor in flexibility and toughness, compared with examples, and it is difficult to meet the requirements of potting and buffering protection of temperature sensitive parts, and it is difficult to improve the performance even if a small amount of silica is added, and the conventional curing method has problems of long curing time.
Comparative example 2 compared with the examples, since the vinyl silicone oil used was a higher viscosity terminal vinyl polydimethylsiloxane (1000 mpa·s), although the resulting casting glue had a lower curing temperature rise and was relatively suitable for the casting of temperature sensitive parts, the resulting casting material had a viscosity that was too high, a poor fluidity, and was difficult to meet the requirements for complex gap casting, and was significantly hardened at-50 ℃ at low temperatures, exhibiting poor low temperature flexibility, and because of the lack of long curing time with conventional curing means, it was demonstrated that the use of a high viscosity terminal vinyl polysiloxane was unsuitable for complex gap casting and low temperature flexibility requirements.
The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the invention.
All of the features disclosed in this specification, except for mutually exclusive features, may be combined in any manner.

Claims (10)

1. An ultralow-viscosity rapidly-curable low-temperature flexible liquid organic silicon encapsulating material is characterized in that the composition comprises the following components:
the viscosity of the mixture of vinyl silicone oil and inert (silicone) oil is not more than 300mpa.s.
2. The ultra-low viscosity fast curable low temperature flexible silicone potting material of claim 1, wherein the a-component vinyl silicone oil is selected from at least one of vinyl-terminated dimethyl silicone oil, vinyl-terminated diethyl silicone oil, vinyl-terminated dimethyl diphenyl silicone oil, vinyl-terminated dimethyl phenyl silicone oil, vinyl-terminated trifluoropropyl silicone oil, and liquid MV (D) Q vinyl silicone resin, wherein the vinyl silicone oil contains at least 2 vinyl functional groups attached to silicon atoms, and the viscosity of the vinyl silicone oil is no more than 10000 mPa-s, no less than 150 mPa-s; the amount of the component having a viscosity of 1000 mPas or more in the vinyl silicone oil is 50 parts by mass or less based on 100 parts by mass of the component A.
3. The ultralow-viscosity rapidly curable low-temperature flexible silicone potting material according to claim 2, wherein the amount of the component with a viscosity of 1000 mPa-s or more in the vinyl silicone oil is 30 parts by mass or less per 100 parts by mass of the component a.
4. The ultra-low viscosity fast curable low temperature flexible silicone potting material of claim 1, wherein the B-component inert (silicone) oil is selected from at least one of a dimethyl silicone oil, a diethyl silicone oil, a dimethyl monophenyl silicone oil, a dimethyl diphenyl silicone oil, a trifluoropropyl silicone oil, a liquid paraffin (oil), a di (iso) octyl sebacate, a di (iso) octyl phthalate, and a viscosity at 25 ℃ of not more than 50 mPa-s.
5. The ultralow-viscosity rapidly curable low-temperature flexible silicone potting material according to claim 1, wherein the hydrogen-containing silicone oil of component C contains at least two hydrogen atoms connected with silicon atoms in a single molecule, and the content of the hydrogen atoms connected with silicon atoms is not less than 0.15%.
6. The ultra-low viscosity, rapidly curable low temperature flexible silicone potting material of claim 1, wherein the inhibitor D Cheng Fensuo is selected from at least one of 1-ethynyl cyclohexanol, 3-methyl-1-pentyn-3-ol, 3, 5-dimethyl-1-hexyn-3-ol, 3-methyl-3-trimethylsiloxy-1-butyne, trimethyl (3- ((trimethylsiloxy) prop-1-yn-1-yl) silane, polyvinyl siloxane, tetramethyl tetra-vinyl cyclotetrasiloxane telomer, tetramethyl-divinyl disiloxane.
7. The ultralow-viscosity rapidly-curable low-temperature flexible organic silicon potting material according to claim 1, wherein the E component platinum-rhodium catalyst is selected from one of a platinum catalyst and a rhodium catalyst, wherein the platinum catalyst is a platinum complex formed by reacting chloroplatinic acid with alkene, alcohol, alkyne and triphenylphosphine, and the rhodium catalyst is a complex of triphenylphosphine and rhodium; the olefin is selected from one of tetramethyl divinyl disiloxane, tetramethyl tetravinyl cyclodisiloxane, 1, 3-divinyl-1, 3 diphenyl-dimethyl disiloxane, propylene, vinyl alkoxy silane, vinyl siloxane, 1-hydroxy, 3-vinyl-tetramethyl disiloxane and vinyl cyclosiloxane; the alcohol is ethanol or isopropanol, and the alkyne is acetylene.
8. The ultralow-viscosity rapidly curable low-temperature flexible organic silicon potting material according to claim 1, wherein the BET specific surface area of the hydrophobic silica of the F component is 50-300 m 2 And/g, the carbon content is 2-6%.
9. The method for preparing the ultralow-viscosity rapidly-curable low-temperature flexible liquid organic silicon encapsulating material according to any one of claims 1 to 8, which is characterized by comprising the following steps:
a. uniformly mixing vinyl silicone oil, inert (silicon) oil and hydrophobic silicon dioxide to obtain base adhesive;
b. then mixing the base adhesive with hydrogen silicone oil and inhibitor, and dispersing uniformly;
c. and adding a platinum-rhodium catalyst, and rapidly stirring and mixing to obtain the flexible liquid organosilicon elastic potting material.
10. Use of the ultra-low viscosity, rapidly curable, low temperature flexible liquid silicone potting material of claim 1, wherein the potting is performed in various gap structures of the device or assembly, cured, and then the device or assembly is placed in use at an ambient temperature above-50 ℃.
CN202310725809.XA 2023-06-19 2023-06-19 Ultralow-viscosity rapidly-curable low-temperature flexible organic silicon potting material, preparation method and application Pending CN116875270A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202310725809.XA CN116875270A (en) 2023-06-19 2023-06-19 Ultralow-viscosity rapidly-curable low-temperature flexible organic silicon potting material, preparation method and application

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202310725809.XA CN116875270A (en) 2023-06-19 2023-06-19 Ultralow-viscosity rapidly-curable low-temperature flexible organic silicon potting material, preparation method and application

Publications (1)

Publication Number Publication Date
CN116875270A true CN116875270A (en) 2023-10-13

Family

ID=88255870

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202310725809.XA Pending CN116875270A (en) 2023-06-19 2023-06-19 Ultralow-viscosity rapidly-curable low-temperature flexible organic silicon potting material, preparation method and application

Country Status (1)

Country Link
CN (1) CN116875270A (en)

Similar Documents

Publication Publication Date Title
US6573328B2 (en) Low temperature, fast curing silicone compositions
KR101187594B1 (en) Curable organopolysiloxane composition
EP0305032B1 (en) Method for preparing clear polyorganosiloxane elastomers
CN107573693B (en) Liquid silicone resin foam material and preparation method thereof
CN106103594B (en) Silicone gel composition
JP3638746B2 (en) Silicone gel composition and silicone gel for sealing and filling electric and electronic parts
CN105164208A (en) Thermally conductive silicone composition and cured product of same
US6001918A (en) Silicone gel composition for use as a sealant and a filler for electrical and electronic components and a gel prepared from this composition
WO2013017090A1 (en) Halogen-free flame-retardant addition type organosilicon encapsulant for electronic appliances
CN106244093A (en) Room temperature vulcanization addition type organic silicon pouring sealant composition
EP2350197A1 (en) Sealant or filler for electrical and electronic components, and electrical and electronic components
JP3746394B2 (en) Silicone gel composition
CN106833510A (en) New energy high heat conduction low-gravity organic silicon potting adhesive
CN102234429A (en) Composition for silicone resin
CN106167621A (en) Flame-retardant room temperature vulcanized liquid silicone rubber
JP4897149B2 (en) Silicone composition and silicone adhesive produced therefrom
TW202041574A (en) Polyorganosiloxane and thermally conductive silicone composition thereof
JP7444857B2 (en) Room-temperature curable organopolysiloxane compositions and protective agents or adhesive compositions for electrical and electronic parts
US20220363834A1 (en) Thermally conductive silicone composition and method for producing the same
CN115612446B (en) Heat-conducting addition type organic silicon composition for encapsulation
CN115895275A (en) High-flexibility heat-conducting double-component addition type organic silicon gel and preparation method thereof
JP4553562B2 (en) Adhesive polyorganosiloxane composition
EP0676450B1 (en) Thixotropic fluorosilicone gel composition
CN116875270A (en) Ultralow-viscosity rapidly-curable low-temperature flexible organic silicon potting material, preparation method and application
US5532294A (en) Thixotropic fluorosilicone gel composition

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination