CN113801369A - Polymer foaming microsphere and preparation method and application thereof - Google Patents

Polymer foaming microsphere and preparation method and application thereof Download PDF

Info

Publication number
CN113801369A
CN113801369A CN202010574362.7A CN202010574362A CN113801369A CN 113801369 A CN113801369 A CN 113801369A CN 202010574362 A CN202010574362 A CN 202010574362A CN 113801369 A CN113801369 A CN 113801369A
Authority
CN
China
Prior art keywords
foaming
polymer
rubber
microspheres
monomers
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
CN202010574362.7A
Other languages
Chinese (zh)
Inventor
沈后平
徐新连
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.)
Lu Xiaodai
Original Assignee
Lu Xiaodai
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 Lu Xiaodai filed Critical Lu Xiaodai
Priority to CN202010574362.7A priority Critical patent/CN113801369A/en
Publication of CN113801369A publication Critical patent/CN113801369A/en
Pending legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
    • C08J9/32—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof from compositions containing microballoons, e.g. syntactic foams
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J13/00—Colloid chemistry, e.g. the production of colloidal materials or their solutions, not otherwise provided for; Making microcapsules or microballoons
    • B01J13/02—Making microcapsules or microballoons
    • B01J13/06—Making microcapsules or microballoons by phase separation
    • B01J13/14—Polymerisation; cross-linking
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F2/00—Processes of polymerisation
    • C08F2/12—Polymerisation in non-solvents
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
    • C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
    • C08F220/42—Nitriles
    • C08F220/44—Acrylonitrile
    • C08F220/48—Acrylonitrile with nitrogen-containing monomers
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
    • C08J9/0014—Use of organic additives
    • C08J9/0023—Use of organic additives containing oxygen
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
    • C08J9/0014—Use of organic additives
    • C08J9/0028—Use of organic additives containing nitrogen
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
    • C08J9/0014—Use of organic additives
    • C08J9/0038—Use of organic additives containing phosphorus
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
    • C08J9/0061—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof characterized by the use of several polymeric components
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
    • C08J9/0066—Use of inorganic compounding ingredients
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
    • C08J9/0095—Mixtures of at least two compounding ingredients belonging to different one-dot groups
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2203/00—Foams characterized by the expanding agent
    • C08J2203/22—Expandable microspheres, e.g. Expancel®
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2205/00—Foams characterised by their properties
    • C08J2205/04—Foams characterised by their properties characterised by the foam pores
    • C08J2205/044—Micropores, i.e. average diameter being between 0,1 micrometer and 0,1 millimeter
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2309/00—Characterised by the use of homopolymers or copolymers of conjugated diene hydrocarbons
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2383/00—Characterised by the use of 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; Derivatives of such polymers
    • C08J2383/04—Polysiloxanes
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2407/00—Characterised by the use of natural rubber
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2471/00—Characterised by the use of polyethers obtained by reactions forming an ether link in the main chain; Derivatives of such polymers
    • C08J2471/02—Polyalkylene oxides
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2483/00—Characterised by the use of 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; Derivatives of such polymers
    • C08J2483/04—Polysiloxanes
    • C08J2483/05—Polysiloxanes containing silicon bound to hydrogen

Abstract

The invention discloses a polymer foaming microsphere and a preparation method and application thereof, wherein the preparation method of the polymer foaming microsphere comprises the following steps: mixing an oil phase mixture with an aqueous dispersion medium, and reacting to obtain the polymer expanded microspheres, wherein the oil phase mixture comprises a polymerizable monomer, a crosslinking agent and at least one foaming agent. The polymer foaming microsphere has a core-shell structure, wherein the polymer is a shell, the foaming agent is a core, and meanwhile, the surfactant is introduced to the outside of the polymer, so that the dispersibility and the flowability of the polymer foaming microsphere are improved. The polymer foaming microspheres prepared by the invention can be directly applied to rubber, can be directly foamed in the rubber vulcanization process, does not need to change the existing rubber production process, and reduces the rubber density.

Description

Polymer foaming microsphere and preparation method and application thereof
Technical Field
The invention relates to the field of foaming materials, in particular to a polymer foaming microsphere and a preparation method and application thereof.
Background
The heat expandable polymer microsphere (polymer foaming microsphere) is a multifunctional foaming material with wide application, can be applied to the fields of printing ink, explosive, paper and the like, and can also be applied to rubber, plastic and coating as a filling agent to reduce the weight of the material and improve the elasticity, sound insulation and heat insulation effects of the material.
The polymer foamed microspheres have a structure that a foaming agent is coated by a polymer shell, and are generally prepared by a suspension polymerization method. The application of the polymer foaming microspheres can play a role in filling or other roles by adding the foamed polymer microspheres into other materials, and can also add unfoamed polymer microspheres into other materials to carry out microsphere foaming in the processing process of other materials. The application of the polymeric microspheres relates to how to foam the polymeric microspheres, for example, by heating.
The rubber has high elasticity, can still keep good resilience after being processed into a foaming material, can be used as a buffer material or a shockproof material, and can be applied to the buffer and shock absorption of automobiles, household appliances, mechanical products, ships, trains, packaging liners, air conditioners and the like as a matched material.
However, in the prior art, the polymer foaming microspheres are less applied to the preparation of rubber foaming materials.
Disclosure of Invention
In order to overcome the above problems, the present inventors have conducted intensive studies to develop a polymer expanded bead, a method for preparing the same, and applications thereof, the method comprising: mixing an oil phase mixture with an aqueous dispersion medium, and reacting to obtain the polymer expanded microspheres, wherein the oil phase mixture comprises a polymerizable monomer, a crosslinking agent and at least one foaming agent. The polymer foaming microsphere has a core-shell structure, wherein the polymer is a shell, the foaming agent is a core, and meanwhile, the surfactant is introduced to the outside of the polymer, so that the dispersibility and the flowability of the polymer foaming microsphere are improved. The polymer foaming microspheres prepared by the invention can be directly applied to rubber, and directly foam in the rubber curing process, the existing rubber production process is not required to be changed, and the rubber density is reduced, so that the invention is completed.
The invention aims to provide a preparation method of polymer foaming microspheres, which comprises the following steps: mixing an oil phase mixture with an aqueous dispersion medium, and reacting to obtain the polymer expanded microsphere, wherein the oil phase mixture comprises a polymerizable monomer, a cross-linking agent and two foaming agents.
The polymerizable monomer is selected from one or more of nitrile monomers, carboxyl-containing monomers, halogenated vinyl monomers, (methyl) acrylate monomers, acrylamide monomers, maleic amide monomers, unsaturated monoolefin monomers, vinyl ketone monomers and N-vinyl monomers;
the cross-linking agent is selected from one or more of pentaerythritol trimethacrylate, dipentaerythritol hexamethacrylate, allyl methacrylate, trimethylolpropane trimethacrylate, triallyl isocyanate and triallyl isocyanurate,
the first foaming agent is one or more selected from hydrocarbon or halogenated hydrocarbon compounds containing 3-10 carbon atoms, azodiisobutyronitrile, azodicarbonamide and N-N-dimethylene pentamethylene tetramine, and the second foaming agent is a hydroxyl-containing compound, preferably an alcohol compound.
The polymerizable monomer comprises a nitrile monomer, a (methyl) acrylate monomer and an acrylamide monomer, and preferably, the polymerizable monomer further comprises a polar end-containing monomer.
The method further comprises the following steps: and mixing the polymer foaming microspheres with a surfactant to obtain the modified polymer foaming microspheres.
The surfactant comprises one or more of metal soaps, synthetic waxes, resin powder, inorganic powder and the like, and is preferably one or more of inorganic powder.
The inorganic powder is selected from one or more of talc, mica, bentonite, sericite, carbon black, aluminum disulfide, tungsten disulfide, graphite fluoride, calcium fluoride, boron nitride, silicon dioxide, alumina, mica, calcium carbonate, calcium hydroxide, calcium phosphate, magnesium hydroxide, magnesium phosphate, barium sulfate, barium dioxide, zinc oxide, ceramic beads, glass beads, crystal beads, montmorillonite and the like.
The invention provides a polymer foaming microsphere, which is preferably prepared by adopting the method.
The invention provides an application of polymer foaming microspheres in rubber.
The invention provides a rubber composition which comprises a rubber matrix and a foaming agent, wherein the foaming agent is polymer foaming microspheres, and preferably, the polymer foaming microspheres account for 2-8 parts by weight based on 100 parts by weight of the rubber matrix.
The rubber composition also includes a modified metal carboxyethylphenylphosphinate, a melamine cyanurate, and zinc borate.
The invention has the following beneficial effects:
(1) in the preparation method of the polymer foaming microsphere provided by the invention, the hydroxyl-containing compound is used as another foaming agent, so that the foaming performance of the obtained polymer foaming microsphere can be improved, the foaming agent and the hydrocarbon or halogenated hydrocarbon compound act synergistically to further improve the foaming multiplying power, form more uniform polymer foaming microsphere and improve the temperature resistance of the polymer foaming microsphere;
(2) in the method provided by the invention, the surfactant is introduced, so that the air tightness of the polymer shell is improved, the escape of an internal foaming agent is effectively prevented, the dispersity of the polymer foaming microspheres can be improved, the foaming effect is further improved, and the obtained foam holes are compact and uniform when the polymer foaming microsphere is applied to rubber;
(3) the method provided by the invention adopts the monomer containing the polar end, improves the dispersibility of the polymer microsphere, and simultaneously obtains the polymer foaming microsphere with higher expansion performance;
(4) the polymer foaming microspheres provided by the invention can be applied to rubber and used as a rubber foaming agent, the foaming agent is directly foamed in the rubber vulcanization process, and after the polymer foaming microspheres are foamed, the volume is increased, so that the rubber can be simultaneously foamed and vulcanized, the rubber density is reduced, the quality is reduced, the obtained rubber has good thermal property and mechanical property, and an expansion flame-retardant system is added to improve the flame-retardant property of the rubber.
Detailed Description
The present invention will be described in further detail below with reference to preferred embodiments. The features and advantages of the present invention will become more apparent from the description.
According to the present invention, there is provided a method for preparing polymer foamed microspheres, the method comprising: preparing an oil phase mixture; preparing an aqueous dispersion medium, and dispersing the oil phase mixture in the aqueous dispersion medium for suspension polymerization to prepare the polymer foaming microspheres.
According to the invention, the oil phase mixture comprises a polymerizable monomer and a cross-linking agent.
According to the present invention, the polymerizable monomer includes one or more of nitrile-based monomers, carboxyl-containing monomers, halogenated vinyl-based monomers, (meth) acrylate-based monomers, acrylamide-based monomers, maleimide-based monomers, unsaturated monoolefin-based monomers, vinyl ketone-based monomers, N-vinyl monomers, vinyl naphthalene salts, and the like.
According to the present invention, a nitrile monomer such as one or more of acrylonitrile, methacrylonitrile, 2-methyl-2-propenyl, 2-chloroacrylonitrile, 2-ethoxyacrylonitrile, fumaronitrile, 2-butenenitrile and the like is preferably one or more selected from acrylonitrile, 2-chloroacrylonitrile, 2-ethoxypropionitrile, fumaronitrile, and more preferably selected from acrylonitrile.
According to the invention, the monomer containing carboxyl is selected from one or more of acrylic acid, methacrylic acid, ethacrylic acid, crotonic acid, cinnamic acid, maleic acid, itaconic acid, fumaric acid, citraconic acid, chloromaleic acid and the like, and the halogenated vinyl monomer is selected from one or more of chloroethylene, vinylidene chloride and the like.
According to the present invention, the (meth) acrylate monomer is one or more selected from methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, octadecyl (meth) acrylate, phenyl (meth) acrylate, isobornyl (meth) acrylate, and the like.
According to the present invention, the (meth) acrylamide monomer is selected from one or more of acrylamide, substituted acrylamide, methacrylamide, N-dimethylacrylamide, substituted methacrylamide, and the like, and is preferably selected from N, N-methacrylamide.
According to the present invention, the maleimide-based monomer is selected from one or more unsaturated monoolefin-based monomers selected from N-phenylmaleimide, N-cyclohexylmaleimide and the like.
According to the present invention, the unsaturated monoolefin monomer is selected from one or more of ethylene, propylene, isobutylene and the like.
According to the invention, the polymerizable monomers also comprise styrene,
Styrene monomers such as α -methylstyrene; vinyl ether monomers such as vinyl methyl ether, vinyl ethyl ether and vinyl isobutyl ether; vinyl ketone monomers such as vinyl methyl ketone; the N-vinyl monomer is one or more selected from N-vinyl carbazole, N-vinyl pyrrolidone, etc.
According to a preferred embodiment of the present invention, the polymerizable monomer comprises the following raw material components in parts by weight:
40 to 90 parts by weight, preferably 45 to 85 parts by weight of a nitrile monomer
1 to 30 parts by weight of acrylamide monomer, preferably 5 to 25 parts by weight
5 to 40 parts by weight, preferably 10 to 30 parts by weight of a (meth) acrylate monomer.
The inventor finds that the polymerizable monomer adopts nitrile monomers, (methyl) acrylate monomers and acrylamide monomers to obtain higher initial foaming temperature, and the obtained polymer foaming microspheres have high heat resistance and gas barrier property.
According to a preferred embodiment of the invention, the polymerizable monomers comprise acrylonitrile, methyl methacrylate, N-dimethylacrylamide.
According to the invention, the polymerizable monomer also comprises carboxyl-containing monomers, and the oil phase is one or more of acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid and citraconic acid, preferably acrylic acid.
According to the present invention, the carboxyl-containing monomer is contained in an amount of 1 to 30 parts by weight, preferably 5 to 25 parts by weight, based on 40 to 90 parts by weight of the nitrile-based monomer.
According to the invention, the polymerizable monomer also comprises a polar end-containing monomer, wherein the polar end-containing monomer is one or more of styrene sulfonic acid and styrene sodium sulfonate.
According to the invention, the polymerizable monomer is subjected to suspension polymerization to obtain the polymer shell, and the polar end-containing monomer is introduced onto the polymer shell, so that the dispersibility of the obtained polymer foaming microspheres can be improved, and the initial foaming temperature of the polymer foaming microspheres can be increased, thereby preventing the polymer foaming microspheres from foaming in the rubber processing process when being applied to a rubber material, and influencing the rubber processing process and the comprehensive performance of the rubber.
According to a preferred embodiment of the present invention, the polar end group-containing monomer is contained in an amount of 0.1 to 10 parts by weight, preferably 1 to 8 parts by weight, based on 40 to 90 parts by weight of the nitrile-based monomer.
According to the invention, the crosslinking agent is selected from divinylbenzene, ethylene glycol di (meth) acrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, 1, 3-propanediol dimethacrylate, 1, 4-butanediol dimethacrylate, 1, 6-hexanediol dimethacrylate, glycerol dimethacrylate, 1, 3-butanediol dimethacrylate, neopentyl glycol dimethacrylate, 1, 10-decanediol dimethacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, dipentaerythritol hexamentaerythritol hexamethacrylate, allyl methacrylate, trimethylolpropane trimethacrylate, polyethylene glycol (200) dimethacrylate, polyethylene glycol (400) dimethacrylate, polyethylene glycol (1, 3-butanediol dimethacrylate, polyethylene glycol dimethacrylate, and mixtures thereof, Polyethylene glycol (600) dimethacrylate, triallyl isocyanate, triallyl isocyanurate, divinyl ether, ethylene glycol divinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, and tetraethylene glycol divinyl ether.
According to a preferred embodiment of the invention, the cross-linking agent is selected from one or more of pentaerythritol trimethacrylate, dipentaerythritol hexamethacrylate, allyl methacrylate, trimethylolpropane trimethacrylate, triallylisocyanate and triallylisocyanurate.
According to the invention, the addition amount of the cross-linking agent is 0.1-0.4% of the total weight of the polymerizable monomer.
According to the present invention, the oil phase mixture further includes a silane coupling agent such as KH550, KH570, and the like.
According to the invention, the addition amount of the silane coupling agent is 1-10% of the total weight of the polymerizable monomers, and preferably 2-8%.
According to the invention, an initiator is also added to the oil phase mixture, the initiator being selected from dicetyl peroxydicarbonate, bis (4-tert-butylcyclohexyl) peroxydicarbonate, dioctanoate peroxide, dibenzoate peroxide, dilaurate peroxide, didecanoic acid peroxide, tert-butyl peracetate, tert-butyl peroxylaurate, tert-butyl peroxybenzoate, tert-butyl hydroperoxide, cumene hydroperoxide, ethylcumene hydroperoxide, diisopropylhydroxydicarboxylate, 2 '-azobis ((2, 4-dimethylvaleronitrile), 2' -Azobisisobutyronitrile (AIBN), 1 '-azobis (cyclohexane-1-carbonitrile), dimethyl 2, 2' -azobis (2-methylpropionate) or 2,2 '-azobis [ 2-methyl-N- (2-hydroxyethyl) -propionyl ] 2, 2' -azobis Amine ] or a plurality of amines.
According to the invention, the amount of the initiator added is 0.1-2%, preferably 0.5-1.5% of the total weight of the polymerizable monomers.
According to the invention, the oil phase mixture also comprises two types of foaming agents, wherein the first type of foaming agent is preferably a hydrocarbon or halogenated hydrocarbon compound containing 3-10 carbon atoms, and is more preferably one or a mixture of more than one selected from propane, cyclopropane, propylene, butane, n-butane, isobutane, cyclobutane, n-pentane, isopentane, cyclopentane, neopentane, n-hexane, isohexane, cyclohexane, heptane, cycloheptane, octane, isooctane, cyclooctane, 2-methylpentane, 2-2 dimethyl butane and petroleum ether.
According to a preferred embodiment of the present invention, the first type of blowing agent is preferably a mixture comprising iso-pentane, iso-octane and n-octane, and the boiling point and preferred composition range of the blowing agent provide the polymer foamed microspheres with suitable expansion temperature and expansion pressure, which is beneficial for preparing the polymer foamed microspheres with good expansion performance and large foaming ratio.
According to the invention, the amount of the first blowing agent added is 10 to 40%, preferably 15 to 30%, more preferably 20% of the total weight of the polymerizable monomers.
According to the invention, a hydroxyl-containing compound is further added into the oil phase mixture as a second foaming agent, preferably an alcohol compound, more preferably an alcohol compound with 3-8 carbon atoms, including but not limited to one or more of methanol, ethanol, propanol, butanol, isobutanol, tert-butanol, n-pentanol, isopentanol, neopentyl alcohol and the like, such as ethanol.
In the invention, the hydroxyl compound can be used as a second foaming agent and a first foaming agent to play a role in synergistic foaming, so that the foaming ratio is improved, the shell of the formed polymer foaming microsphere is more uniform, and the temperature resistance range of the polymer foaming microsphere is widened.
According to the invention, the amount of the second foaming agent is 8-12 parts by weight based on 20-40 parts by weight of the first foaming agent.
According to the invention, a polymerizable monomer, a foaming agent, a crosslinking agent and a silane coupling agent are mixed and dissolved to obtain an oil phase mixture.
According to the present invention, the aqueous dispersion medium comprises water and preferably also a dispersion stabilizer.
According to the present invention, the dispersion stabilizer includes, but is not limited to: colloidal silica, colloidal calcium carbonate, magnesium hydroxide, calcium phosphate, aluminium hydroxide, iron hydroxide, calcium sulphate, sodium sulphate, calcium oxalate, calcium carbonate, barium carbonate, magnesium carbonate or alumina sol, and may also be selected from starch, methyl cellulose, hydroxypropyl methyl cellulose, carboxymethyl cellulose, gum agar, colloidal silica, colloidal clay or aluminium or iron oxide or hydroxide.
According to a preferred embodiment of the invention, the dispersion stabilizer is selected from one or more of calcium phosphate, calcium carbonate, magnesium hydroxide, calcium sulfate, calcium oxalate, and hydroxides of zinc, nickel or manganese.
According to the present invention, the aqueous dispersion medium further comprises a dispersion stabilizing aid, which includes, but is not limited to, one or more of a condensation product of diethanolamine and aliphatic dicarboxylic acid, gelatin, polyvinylpyrrolidone, carboxymethylcellulose, polyethylene oxide and polyvinyl alcohol.
According to the invention, the aqueous dispersion medium is an acidic environment, preferably the pH of the aqueous dispersion medium is 2 to 5, more preferably 2.5 to 3.5, for example 3.
According to the present invention, the dispersion stabilizer is 0.1 to 20 parts by weight and the dispersion stabilizing aid is 0.1 to 10 parts by weight based on 100 parts by weight of deionized water.
According to the present invention, preparing an aqueous dispersion medium comprises: mixing deionized water with a dispersion stabilizer and a dispersion stabilizing auxiliary agent, fully stirring, and uniformly mixing to prepare the aqueous dispersion medium.
According to the present invention, the oil phase mixture and the aqueous dispersion medium are mixed, reacted, and emulsified at the time of mixing, and the emulsification method can be carried out by a stirring method such as a homomixer or a homodisperser, a static analysis method such as a static mixer, a membrane emulsification method, an ultrasonic dispersion method, or a dispersion method such as a microchannel method.
According to the invention, the oil phase mixture and the aqueous dispersion medium are added into a homogenizing mixer for dispersing and mixing to obtain a suspension, the obtained suspension is added into a polymerization reaction kettle for suspension polymerization reaction in a nitrogen environment, preferably, the reaction process is accompanied with stirring to obtain a product, and the obtained product is subjected to suction filtration, washing, drying, crushing and screening to obtain the polymer foaming microspheres.
According to the invention, the suspension polymerization reaction temperature is 30-100 ℃, preferably 40-90 ℃, and more preferably 50-80 ℃; the pressure of the polymerization reaction kettle is 0.5-2.0 MPa, preferably 0.8-1.6 MPa; the suspension polymerization reaction time is 6-24 h, preferably 10-20 h.
According to the present invention, the preparation method further comprises: the polymer foaming microspheres are mixed with a surfactant to obtain modified polymer foaming microspheres, and the surface modification is carried out on the polymer foaming microspheres, so that the dispersibility and the flowability of the polymer foaming microspheres can be improved.
According to the present invention, the surfactant includes, but is not limited to, metal soaps, synthetic waxes, resin powder, inorganic powder, etc., the metal soaps include, but is not limited to, one or more of magnesium stearate, calcium stearate, zinc stearate, barium stearate, lithium stearate, etc.; the synthetic wax is selected from one or more of polyethylene wax, laurylamine, myristic acid amide, hard amide, hardened castor oil, etc.; the resin powder is selected from one or more of polyacrylamide, polyimide, nylon, polymethyl methacrylate, polyethylene, polytetrafluoroethylene and the like; the inorganic powder is selected from one or more of talc, mica, bentonite, sericite, carbon black, aluminum disulfide, tungsten disulfide, graphite fluoride, calcium fluoride, boron nitride, silicon dioxide, aluminum oxide, mica, calcium carbonate, calcium hydroxide, calcium phosphate, magnesium hydroxide, magnesium phosphate, barium sulfate, barium dioxide, zinc oxide, ceramic beads, glass beads, crystal beads, montmorillonite and the like.
According to a preferred embodiment of the present invention, the surfactant is an inorganic powder, preferably a montmorillonite, more preferably an organically modified montmorillonite selected from montmorillonite modified with one or more of dodecyltrimethylammonium bromide (DTAB), hexadecyltrimethylammonium bromide (CTAB), octadecyltrimethylammonium bromide (OTAB) and hexadecyltrimethylammonium chloride (CTAC).
According to the invention, the preparation of the organic modified montmorillonite comprises the following steps: mixing montmorillonite and deionized water, stirring for 0.5-2 h, adding one or more of DTAB, CTAB, OTAB and CTAC, continuously stirring for 8-12 h at 70-90 ℃, performing suction filtration and washing until no bromide ions or chloride ions are detected, then drying for 18-36 h at 100-120 ℃, and grinding and sieving to obtain the organically modified montmorillonite.
According to the present invention, the surface modifier is attached in an amount of 0.1 to 50 parts by weight, preferably 5 to 30 parts by weight, based on 100 parts by weight of the polymer expanded microspheres before modification.
According to the invention, the average particle size of the prepared polymer foaming microspheres is 10-50 μm, preferably 20-45 μm, more preferably 30-40 μm, and the maximum foaming ratio of the polymer foaming microspheres is 50-200 times.
According to the invention, the initial expansion temperature of the obtained polymer foaming microspheres is 50-150 ℃, and the maximum expansion temperature is 190-240 ℃.
According to the invention, the polymer foaming microspheres are prepared through suspension polymerization reaction, the polymer foaming microspheres are prepared by coating foaming agent with polymer, the obtained polymer foaming microspheres have a core-shell structure, the shell is polymer, the core is foaming agent, when the polymer foaming microspheres are heated to a certain temperature, the shell is softened, the foaming agent generates gas, the shell is expanded, the volume of the polymer foaming microspheres is increased, and the foaming effect is realized.
The invention prepares polymer foaming microspheres by a suspension polymerization method, the suspension polymerization method takes a water phase as a medium, a polymerizable monomer and a foaming agent in an oil phase are dispersed into fine liquid drops to be suspended in the water phase by mechanical stirring action, then polymerization is initiated, each liquid drop contains the monomer, the foaming agent, an initiator, a cross-linking agent and the like, after polymerization reaction starts, the polymer formed in the liquid drop is positioned at the outer part and surrounded by water, the inner part is dispersed and dissolved by the foaming agent and the monomer, the polymer is insoluble in water and the foaming agent, but part of the monomer is dissolved, the polymer and the foaming agent dispersed in the liquid drop form phase separation and are distributed at the periphery of the liquid drop along with the gradual polymerization of the monomer, the foaming agent is finally wrapped at the center by the polymer along with the gradual progress of the reaction, thereby forming the microsphere with a core-shell structure, the quality and speed of phase separation is decisive for the uniformity of the shell surrounding the microspheres.
The present invention also provides a polymeric foamed microsphere prepared according to the method of the first aspect of the present invention.
The invention also provides an application of the polymer foaming microspheres in rubber.
The silicon rubber is a novel rubber with Si-O-Si bond as a main chain and organic groups as side chains, and has excellent weather resistance. The foamable silicone rubber integrates excellent high and low temperature resistance, electrical insulation and ozone aging resistance of the silicone rubber and light, shock-absorbing, heat-insulating, sealing and other properties of the foam material, is an important material in the field of aerospace, and is widely used as a filling material between structural members.
However, in the prior art, the foaming of the silicone rubber is mostly carried out by adopting a chemical foaming method and an organic foaming agent, but the decomposition rate of the organic foaming agent is high, the rubber matrix has no time to vulcanize and capture the gas generated by the foaming agent, so that the foaming rate is low, the foam holes are uneven, when the silicone rubber is used as a gap filling material for a special-shaped structural part, the silicone rubber cannot be densely filled, and the operation is complex.
The invention also provides a rubber composition, which comprises a rubber matrix and a foaming agent, wherein the foaming agent is polymer foaming microspheres, preferably, based on 100 parts by weight of the rubber matrix, the polymer foaming microspheres are 2-8 parts by weight, and the polymer foaming microspheres are prepared by the method of the first aspect of the invention.
According to the invention, the rubber composition also comprises the following raw material components in parts by weight: 12-18 parts of modified carboxyethyl phenyl hypophosphorous acid metal salt, 1-3 parts of melamine cyanurate and 0.5-2 parts of zinc borate, preferably 15 parts of modified carboxyethyl phenyl hypophosphorous acid metal salt, 13 parts of melamine cyanurate and 1 part of zinc borate.
According to the present invention, a method for preparing a modified metal salt of carboxyethylphenylphosphinic acid comprises: dissolving carboxyethyl phenyl hypophosphorous acid in water to prepare a solution A; adding metal salt into water for dissolving, slowly adding the solution A, and stirring and reacting at the temperature of 90-100 ℃ for 1-2h to obtain a solution B; adjusting the pH value of the solution B to 1-2, adding trimethylolpropane, stirring for reacting for 2-4h, filtering and drying to obtain the modified carboxyethyl phenyl phosphinic acid metal salt.
Preferably, the molar ratio of carboxyethylphenylhypophosphorous acid to the metal salt to trimethylolpropane is (6-9): 3: (2-3).
Preferably, the metal salt is a water-soluble salt of zinc, magnesium, aluminum, lanthanum, cerium.
Preferably, the weight ratio of the modified carboxyethylphenylphosphinic acid metal salt to the melamine cyanurate to the zinc borate is 15: 3: 1.
according to the invention, the rubber composition also comprises the following raw material components in parts by weight: 1 to 4 parts by weight of a silane coupling agent, preferably 2 to 3 parts by weight. Among them, the silane coupling agent is preferably Si-69.
According to the invention, modified carboxyethyl phenyl hypophosphorous acid metal salt, melamine cyanurate and zinc borate which are reasonably proportioned are mutually matched to form an expansion flame-retardant system of the foaming rubber material, wherein the modified carboxyethyl phenyl hypophosphorous acid metal salt is organic hypophosphite which has high charring property during combustion and good compatibility with foaming silicon rubber, and incombustible phosphoric acid, metaphosphoric acid and metal phosphate which are generated during the heating combustion process of the foaming silicon rubber are decomposed to cover the surface of the foaming silicon rubber for heat insulation and oxygen isolation; the melamine cyanurate is heated and decomposed to generate a large amount of non-combustible gas, so that the oxygen content around the foamed silicone rubber is further diluted and isolated, and the heat generated by combustion is reduced; the zinc borate is used as a synergistic flame retardant to improve the carbonization performance of the foamed silicone rubber; the silane coupling agent can improve the uniform dispersion of the modified metal carboxyethyl phenyl phosphinate, the melamine cyanurate and the zinc borate in the foamed silicone rubber and improve the flame retardant property of the foamed silicone rubber.
According to the invention, the rubber composition also comprises a filler, wherein the filler is selected from one or more of titanium dioxide, white carbon black, talcum powder, calcium carbonate, magnesium carbonate, silicic acid and silicate, aluminum hydroxide, magnesium hydroxide, aluminum oxide, aluminum silicate, bentonite, acetylene black, glass fiber and wood powder.
According to the invention, the rubber matrix is selected from one or more of natural rubber, isoprene rubber, styrene-butadiene rubber, chloroprene rubber, nitrile rubber, ethylene propylene rubber and silicon rubber.
According to a preferred embodiment of the invention, the rubber matrix is one or more of natural rubber, isoprene rubber, styrene-butadiene rubber, nitrile rubber and ethylene-propylene rubber, and the rubber composition further comprises the following raw material components in parts by weight: 100 parts of a rubber matrix, 1-5 parts of a vulcanizing agent, 1-2 parts of an accelerator and 20-30 parts of white carbon black, and preferably further comprises 1-2 parts of an auxiliary vulcanizing agent, wherein the vulcanizing agent is sulfur, and the auxiliary vulcanizing agent is triallyl isocyanurate.
According to the invention, the accelerator is selected from one or more of DM (dibenzothiazyl disulfide), NS (N-tert-butyl-2-benzothiazylsulfenamide), TMTM (tetramethylthiuram monosulfide), etc.
According to the invention, the rubber composition also comprises an active agent, wherein the active agent is selected from one or more of stearic acid, polyethylene glycol and diethylene glycol, and is preferably a mixture of stearic acid, polyethylene glycol and diethylene glycol. The active agent is 5 to 12 parts by weight based on 100 parts by weight of the rubber matrix.
According to the invention, the rubber composition also comprises an anti-aging agent, wherein the anti-aging agent is a phenolic compound, preferably one or more of polyhydric phenol, substituted phenol and the like, wherein the polyhydric phenol is preferably 2, 5-di-tert-butyl hydroquinone (DBH), and the substituted phenol is preferably Butylated Hydroxytoluene (BHT). The antioxidant is 0.5 to 1 part by weight based on 100 parts by weight of the rubber substrate.
According to the invention, when the rubber matrix is one or more of natural rubber, isoprene rubber, styrene-butadiene rubber, nitrile rubber and ethylene propylene rubber, the preparation method of the rubber composition comprises the following steps: adding a rubber substrate into an internal mixer for mixing, adding an active agent and an anti-aging agent, adding carbon black and a coupling agent, mixing uniformly, discharging after reaching a certain temperature (such as 140-150 ℃), then placing into an open mill for mixing, cooling through a zinc stearate anti-sticking solution tank, discharging into a sheet through a cold water tank to prepare a base material, adding a vulcanizing agent, an accelerant and polymer expansion microspheres for mixing, cooling through the anti-sticking solution tank and the cold water tank, and discharging the sheet to obtain the rubber composition.
According to another preferred embodiment of the present invention, when the rubber substrate is a silicone rubber, the rubber composition comprises the following raw material components in parts by weight:
100 parts of rubber matrix, 5-25 parts of reinforcing agent, 3-10 parts of polymer foaming microspheres, 2-6 parts of vulcanizing agent, 120-160 parts of filler and 2-7 parts of hydrogenated silicone oil,
preferably, 100 parts by weight of the rubber matrix, 10-20 parts by weight of the reinforcing agent, 5-8 parts by weight of the polymer foamed microspheres, 2-4 parts by weight of the vulcanizing agent, 120-140 parts by weight of the filler and 3-6 parts by weight of the hydrogenated silicone oil.
According to a preferred embodiment of the present invention, the rubber matrix is methyl vinyl silicone rubber, the number average molecular weight is 50 to 70 ten thousand, and the vinyl content is 0.05 to 0.25%.
In the invention, the reinforcing agent such as white carbon black plays a reinforcing role, the mechanical strength of the foamed silicon rubber can be improved, the filler is beneficial to improving the flame resistance of the foamed silicon rubber material and reducing the material cost, and the addition of the hydrogenated silicone oil is beneficial to adjusting the viscosity and the fluidity of the rubber compound and is convenient for calendering.
According to the invention, the vulcanizing agent is selected from one or more of Benzoyl Peroxide (BPO), dicumyl peroxide (DCP), tert-butyl peroxybenzoate (TBPB), 2, 4-dichlorobenzoyl peroxide (DCBP), di-tert-butyl peroxide (DTBP), 2, 5-dimethyl-2, 5-di-tert-butyl hexane peroxide (DBPMH, abbreviated to bis-2, 5).
According to the present invention, the polymeric expanded microspheres are prepared according to the method of the first aspect of the present invention. The polymer foaming microspheres are used as foaming agents for foaming rubber, and expand when being heated, so that the foaming effect is realized.
In the invention, the foaming temperature of the polymer foaming microspheres is lower than the vulcanization temperature of rubber, so that the foaming and vulcanization processes of the rubber are simultaneously completed, and the synchronous molding of the silicon rubber and the structural member is realized.
The invention takes the polymer foaming microspheres as the foaming agent of the rubber, the shell of the polymer foaming microspheres is softened after being heated to a certain temperature, and simultaneously the gas in the shell expands, so that the volume of the polymer foaming microspheres is increased, the core-shell structure is not damaged, the foaming effect is realized in the rubber material, the density of the rubber is reduced, the weight of the rubber material is reduced, the rubber elasticity is improved, the heat insulation effect is improved, and the application range of the rubber is widened.
The rubber composition provided by the invention takes the polymer foaming microspheres as the foaming agent, and the obtained rubber material has compact and uniform cells and low density (for example, less than 0.4 g/cm)3) The mechanical property is good, the obtained rubber material has excellent flame retardant property, for example, the limit oxygen index of the obtained rubber material is more than 33 and even can reach 39, and the rubber material has both ultra-light property, excellent mechanical property and flame retardant property.
According to the present invention, when the rubber substrate is a silicone rubber, the method for producing the rubber composition comprises: according to the weight ratio, putting the rubber substrate into an open mill for mixing, then sequentially adding a reinforcing agent, a filler, a modified carboxyethyl phenyl hypophosphorous acid metal salt, melamine cyanurate, zinc borate, a vulcanizing agent, a foaming agent and hydrogenated silicone oil, and uniformly mixing to obtain a rubber compound; and then putting the mixed rubber into a calender for tabletting, and adjusting the roller spacing according to actual needs to obtain a rubber sheet, namely the rubber composition.
According to the invention, the rubber sheet is foamed, in the process of foaming the rubber sheet, the foaming agent is firstly heated to expand and foam, the temperature is continuously raised, the vulcanizing agent is decomposed, the rubber is vulcanized and molded, and the foaming and vulcanizing processes of the rubber are simultaneously completed, so that the synchronous molding with the structural member is realized.
According to the invention, the silicon rubber sheet can spontaneously fill the die cavity when foaming in the die cavity, so that the clearance of a structural part can be densely filled without being limited by the geometric structure of the die cavity. The foaming and vulcanizing temperature of the silicone rubber sheet obtained by taking the silicone rubber as the rubber matrix is 100-170 ℃, the range is wide, the silicone rubber sheet can be synchronously solidified and molded with a thermosetting structural member, and the use is convenient.
The rubber composition takes the polymer foaming microspheres as the foaming agent, the foaming process is simple, the foaming rate is high, the foaming process and the vulcanization process of the rubber composition are simultaneously completed, and the rubber composition and a structural member are synchronously molded, so that the rubber composition has practical application value, for example, the silicone rubber obtained by using the polymer microsphere foaming as the foaming agent has good thermal properties (for example, the thermal weight loss of 1 hour at 200 ℃ is lower than 1.07%, the thermal weight loss of 1 hour at 250 ℃ is lower than 5.18) and mechanical properties, and an expansion flame-retardant system is added in the rubber composition, so that the flame-retardant property of the silicone rubber is improved, and for example, the limit oxygen index of the obtained silicone rubber can reach 34.
In the present invention, the expansion ratio (expansion ratio at the time of maximum expansion of the microspheres), i.e., the maximum expansion ratio, is calculated as follows.
The minimum foam density is calculated from static mechanical thermal analysis (i.e., TMA) testing of the blowing agent, and is calculated as follows:
where m is the mass of the blowing agent to be weighed and V is the volume at which the maximum height of the foam is reached,
v-h-pi-r crucible2H, where h is the displacement of the TMA probe
The rho is m/V is m/(pi r)2*h)，
The inner radius of the crucible measured by a vernier caliper is about 3.4mm, the height unit is mm, the mass unit is mg, and the calculation formula of the foaming density is as follows:
rho m/V m/(36.3 h) in mg/mm3Converted to international units of Kg/m3。
Maximum expansion ratio [ rho ]0/ρmaxWhere ρ is0Density of unfoamed thermally expandable microspheres, pmaxThe density of the thermally expandable microspheres at the time of foaming to the maximum height is obtained, thereby obtaining the foaming ratio of the polymer microspheres.
Examples
Example 1
Mixing 45g of acrylonitrile, 25g of N, N-methacrylamide, 30g of methyl methacrylate, 5g of sodium styrene sulfonate, 0.3g of allyl methacrylate, 10g of isopentane, 10g of isooctane, 10g of ethanol, 2g of KH550 and 1g of AIBN to obtain an oil phase mixture;
mixing 200g of deionized water, 20g of magnesium hydroxide and 2g of polyvinylpyrrolidone, and then adjusting the pH to 3.0 as an aqueous dispersion medium;
mixing the oil phase mixture and the aqueous dispersion medium, dispersing for 3 minutes at the rotation speed of 10000rpm by a homomixer to prepare a suspension, then placing the suspension in a polymerization reactor, replacing with nitrogen, setting the pressure of the polymerization reactor to be 0.8MPa, the polymerization temperature to be 60 ℃, and the polymerization time to be 20 hours, and polymerizing to obtain the polymer foaming microspheres.
Examples 2 to 5 and comparative examples 1 to 2
The kinds, amounts and process conditions of the raw materials used in examples 2 to 5 and comparative examples 1 to 2 are shown in Table 1, and different polymer expanded beads were prepared and the properties of the obtained polymer expanded beads were measured and shown in Table 2.
TABLE 1
Figure BDA0002550797900000181
Figure BDA0002550797900000191
TABLE 2
Figure BDA0002550797900000192
As can be seen from the table 1-2, the alcohol compound, the sodium styrene sulfonate and the acrylamide monomer are added, and the alcohol compound and the hydrocarbon foaming agent are foamed in a synergistic manner, so that the foaming ratio of the obtained polymer foamed microsphere is higher, such as 58-65 times, the initial foaming temperature is increased, such as 105-120 ℃ of the initial foaming temperature range, the foaming characteristic of the polymer foamed microsphere is improved, and the application of the polymer foamed microsphere is widened.
Example 6
100 parts by weight of silicone rubber and 16 parts by weight of white carbon black are mixed in a mixer, 50 parts by weight of talcum powder, 80 parts by weight of aluminum hydroxide, 3 parts by weight of DCP and 8 parts by weight of polymer foaming microspheres prepared in example 1 are sequentially added, 15 parts by weight of modified carboxyethyl phenyl phosphinate metal salt, 2 parts by weight of melamine cyanurate and 1 part by weight of zinc borate are added, and 5 parts by weight of hydrogenated silicone oil is added to prepare rubber compound;
putting the rubber compound into a calender for sheet discharge, and adjusting the roller distance according to the size of the cavity of the die and the required foaming multiplying power to obtain a silicon rubber sheet with the thickness of 2 mm;
and (3) standing the silicon rubber sheet for 24h, attaching the silicon rubber sheet to the wall of a mold cavity with the thickness of 8mm, closing the mold, vulcanizing and foaming in an oven, heating at the rate of 3 ℃/min to 150 ℃, and vulcanizing for 1.5h to obtain the foamed silicon rubber.
Example 7
The procedure of example 6 was repeated except that the polymer expanded beads prepared in example 1 were replaced with the polymer expanded beads prepared in example 2, and the other procedures were the same as in example 6, to obtain a silicone rubber after foaming.
Example 8
The procedure of example 6 was repeated except that the polymer expanded beads prepared in example 1 were replaced with the polymer expanded beads prepared in example 3, and the other procedures were the same as in example 6, to obtain a silicone rubber after foaming.
Example 9
The procedure of example 6 was repeated except that the polymer expanded beads prepared in example 1 were replaced with the polymer expanded beads prepared in example 4, and the other procedures were the same as in example 6, to obtain a silicone rubber after foaming.
Example 10
The procedure of example 6 was repeated except that the polymer expanded beads prepared in example 1 were replaced with the polymer expanded beads prepared in example 5, and the other procedures were the same as in example 6, to obtain a silicone rubber after foaming.
Example 11
Mixing 20kg of natural rubber and 70kg of butadiene rubber, adding the mixture into an internal mixer, uniformly mixing, adding 0.8kg of stearic acid, 2.6kg of polyethylene glycol and 1.2kg of diethylene glycol, then adding 0.5g of DBH and 0.3g of BHT, fully and uniformly mixing, then adding 1.6kg of silane coupling agent and 35kg of white carbon black, uniformly mixing, and discharging when the temperature reaches 140 ℃;
putting the obtained mixed material into an open mill, passing through a zinc stearate anti-sticking solution tank with the concentration of 1%, then passing through a cold water tank with the temperature of 16 ℃, cooling, and taking out the mixture to prepare a base material;
weighing a base material, adding 1kg of insoluble sulfur, 1.2kg of DM, 0.3kg of NS and 0.15kg of TMTM, 12kg of modified carboxyethyl phenyl phosphinate metal salt, 1kg of melamine cyanurate and 0.5kg of zinc borate into the base material, and 3kg of the polymer expanded microspheres prepared in the embodiment 1 into the base material, uniformly mixing, cooling the mixture by an anti-sticking solution tank and a cold water tank, and then discharging the mixture to obtain a mixed rubber.
And (3) placing the rubber composition on a flat vulcanizing agent, vulcanizing and foaming by adopting a mould pressing method, wherein the foaming temperature is 160 ℃, and obtaining the foamed rubber material.
Example 12
The procedure in example 11 was repeated except that the polymer expanded beads prepared in example 1 were replaced with the polymer expanded beads prepared in example 2, and the other procedures were the same as in example 11, to obtain a rubber material after foaming.
Example 13
The procedure in example 11 was repeated except that the polymer expanded beads prepared in example 1 were replaced with the polymer expanded beads prepared in example 3, and the other procedures were the same as in example 11, to obtain a rubber material after foaming.
Example 14
The procedure in example 11 was repeated except that the polymer expanded beads prepared in example 1 were replaced with the polymer expanded beads prepared in example 4, and the other procedures were the same as in example 11, to obtain a rubber material after foaming.
Example 15
The procedure in example 11 was repeated except that the polymer expanded beads prepared in example 1 were replaced with the polymer expanded beads prepared in example 5, and the other procedures were the same as in example 11, to obtain a rubber material after foaming.
Comparative example 3
Putting 100 parts by weight of silicone rubber into a mixing roll for mixing, sequentially adding 130 parts by weight of talcum, 3 parts by weight of DCP and 8 parts by weight of foaming agent AC, and then adding 5 parts by weight of hydrogenated silicone oil to prepare rubber compound;
putting the rubber compound into a calender for sheet discharge, and adjusting the roller distance according to the size of the cavity of the die and the required foaming multiplying power to obtain a silicon rubber sheet with the thickness of 2 mm;
and (3) standing the silicon rubber sheet for 24h, attaching the silicon rubber sheet to the wall of a mold cavity with the thickness of 8mm, closing the mold, vulcanizing and foaming in an oven, heating at the rate of 3 ℃/min to 150 ℃, and vulcanizing for 1.5h to obtain the foamed silicon rubber.
Comparative example 4
The procedure of example 6 was repeated except that the polymer expanded beads prepared in example 1 were replaced with the polymer expanded beads prepared in comparative example 1, and the other procedures were the same as in example 6, to obtain a silicone rubber after foaming.
Comparative example 5
The procedure of example 6 was repeated except that the polymer expanded beads prepared in example 1 were replaced with the polymer expanded beads prepared in comparative example 2, and the other procedures were the same as in example 6, to obtain a silicone rubber after foaming.
Comparative example 7
Mixing 20kg of natural rubber and 70kg of butadiene rubber, adding the mixture into an internal mixer, uniformly mixing, adding 0.8kg of stearic acid, 2.6kg of polyethylene glycol and 1.2kg of diethylene glycol, then adding 0.5g of DBH and 0.3g of BHT, fully and uniformly mixing, then adding 1.6kg of silane coupling agent and 35kg of white carbon black, uniformly mixing, and discharging when the temperature reaches 140 ℃;
putting the obtained mixed material into an open mill, passing through a zinc stearate anti-sticking solution tank with the concentration of 1%, then passing through a cold water tank with the temperature of 16 ℃, cooling, and taking out the mixture to prepare a base material;
weighing the base material, adding 1kg of insoluble sulfur, 1.2kg of DM, 0.3kg of NS and 0.15kg of TMTM, uniformly mixing 3kg of foaming agent AC, cooling by an anti-sticking solution tank and a cold water tank, and then discharging to obtain the rubber compound.
And (3) placing the rubber composition on a flat vulcanizing agent, vulcanizing and foaming by adopting a mould pressing method, wherein the foaming temperature is 160 ℃, and obtaining the foamed rubber material.
Examples of the experiments
Experimental example 1
The foamed silicone rubbers obtained in examples 6 to 10 and comparative examples 3 to 5 were subjected to tests of tensile strength, shore hardness, thermogravimetric, thermal conductivity, limiting oxygen index, and cell density, and the test results are shown in table 3.
TABLE 3
Figure BDA0002550797900000231
Figure BDA0002550797900000241
Observing the foamed silicone rubbers obtained in examples 6-10, the foamed silicone rubbers are found to have compact and uniform cells and good foaming effect, while the silicone rubbers obtained in comparative examples 3-5 have non-uniform cells and poor foaming effect. As can be seen from table 3, the foamed silicone rubbers prepared in examples 6 to 10 of the present invention have small cell density, so that the density of the silicone rubber is reduced, the quality of the silicone rubber is reduced, the shore hardness and the limited oxygen index of the obtained foamed silicone rubber are both significantly improved, and the tensile strength is also increased, which indicates that the mechanical properties of the foamed silicone rubber can be improved by foaming the silicone rubber with the polymer foamed microspheres as the foaming agent, and the obtained foamed silicone rubber has good thermal properties, the heat loss of the foamed silicone rubber is low after 1h treatment at 200 ℃ and 1.5h treatment at 250 ℃, the flame retardant properties of the foamed silicone rubber can be significantly improved by adding the modified carboxyethyl phenyl phosphinate metal salt, the melamine cyanurate salt and the zinc borate as the flame retardant, and the limited oxygen index can reach 35.
Experimental example 2
The foamed rubber materials obtained in examples 11 to 15 and comparative example 7 were subjected to tests of tensile strength, thermal conductivity, shore hardness, limiting oxygen index, and density, and the test results are shown in table 4.
TABLE 4
Figure BDA0002550797900000251
As can be seen from Table 4, the rubber materials obtained in examples 11 to 15 had lower densities and densities of less than 0.4g/cm, and the rubber materials obtained in examples 11 to 15 and comparative example 1 had a uniform and dense cell structure and a better foaming effect3Even as low as 0.29g/cm3The thermal stability and the thermal conductivity of the rubber materials obtained in examples 11 to 15 are not obviously changed, the tensile strength is slightly higher than that of comparative example 7, the Shore hardness is higher than that of comparative example 7, and the limiting oxygen index is obviously higher than that of comparative example 7. It is demonstrated that the rubber materials obtained in examples 11 to 15 have excellent flame retardant properties. The flame retardant property of the rubber can be obviously improved by adding modified carboxyethyl phenyl hypophosphorous acid metal salt, melamine cyanurate and zinc borate as flame retardants, and the limited oxygenThe index is above 33 and can even reach 39. The rubber material has the advantages of ultralight property, excellent mechanical property and flame retardant property.
The invention has been described in detail with reference to the preferred embodiments and illustrative examples. It should be noted, however, that these specific embodiments are only illustrative of the present invention and do not limit the scope of the present invention in any way. Various modifications, equivalents and variations may be made in the technical disclosure and embodiments thereof without departing from the spirit and scope of the present invention. The scope of the invention is defined by the appended claims.

Claims (10)

1. A method of making a polymer-expanded microsphere, the method comprising: and mixing the oil phase mixture with an aqueous dispersion medium, and reacting to obtain the polymer expanded microsphere, wherein the oil phase mixture comprises a polymerizable monomer, a cross-linking agent and two foaming agents.
2. The method of claim 1,
the polymerizable monomer is selected from one or more of nitrile monomers, carboxyl-containing monomers, halogenated vinyl monomers, (methyl) acrylate monomers, acrylamide monomers, maleic amide monomers, unsaturated monoolefin monomers, vinyl ketone monomers and N-vinyl monomers;
the cross-linking agent is selected from one or more of pentaerythritol trimethacrylate, dipentaerythritol hexamethacrylate, allyl methacrylate, trimethylolpropane trimethacrylate, triallyl isocyanate and triallyl isocyanurate,
the first foaming agent is one or more selected from hydrocarbon or halogenated hydrocarbon compounds containing 3-10 carbon atoms, azodiisobutyronitrile, azodicarbonamide and N-N-dimethylene pentamethylene tetramine, and the second foaming agent is a hydroxyl-containing compound, preferably an alcohol compound.
3. The method of claim 1, wherein the polymerizable monomer comprises a nitrile monomer, a (meth) acrylate monomer, and an acrylamide monomer, and preferably the polymerizable monomer further comprises a polar end-containing monomer.
4. The method of claim 1, further comprising: and mixing the polymer foaming microspheres with a surfactant to obtain the modified polymer foaming microspheres.
5. The method according to claim 4, wherein the surfactant comprises one or more of but not limited to metal soaps, synthetic waxes, resin powder, inorganic powder and the like, and preferably one or more of inorganic powder.
6. The method according to claim 1, wherein the inorganic powder is selected from one or more of talc, mica, bentonite, sericite, carbon black, aluminum disulfide, tungsten disulfide, graphite fluoride, calcium fluoride, boron nitride, silica, alumina, mica, calcium carbonate, calcium hydroxide, calcium phosphate, magnesium hydroxide, magnesium phosphate, barium sulfate, titanium dioxide, zinc oxide, ceramic beads, glass beads, crystal beads, montmorillonite, etc.
7. A polymer expanded microsphere, preferably obtainable by the process according to any one of claims 1 to 6.
8. The application of the polymer foaming microspheres in rubber.
9. A rubber composition is characterized by comprising a rubber matrix and a foaming agent, wherein the foaming agent is polymer foaming microspheres,
preferably, the polymer foaming microspheres are 2 to 8 parts by weight based on 100 parts by weight of the rubber matrix.
10. The rubber composition of claim 9, further comprising a modified metal carboxyethylphenylphosphinate, melamine cyanurate, and zinc borate.
CN202010574362.7A 2020-06-22 2020-06-22 Polymer foaming microsphere and preparation method and application thereof Pending CN113801369A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010574362.7A CN113801369A (en) 2020-06-22 2020-06-22 Polymer foaming microsphere and preparation method and application thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010574362.7A CN113801369A (en) 2020-06-22 2020-06-22 Polymer foaming microsphere and preparation method and application thereof

Publications (1)

Publication Number Publication Date
CN113801369A true CN113801369A (en) 2021-12-17

Family

ID=78943389

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010574362.7A Pending CN113801369A (en) 2020-06-22 2020-06-22 Polymer foaming microsphere and preparation method and application thereof

Country Status (1)

Country Link
CN (1) CN113801369A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114773693A (en) * 2022-04-12 2022-07-22 达州市嘉源体育用品有限公司 Rubber foaming sole
CN115260877A (en) * 2022-08-02 2022-11-01 广东希贵光固化材料有限公司 UV temporary protective coating for heating film fading and application thereof
TWI796264B (en) * 2022-07-15 2023-03-11 正崴精密工業股份有限公司 Anti-extend-burn and flame-retardant material
CN116284949A (en) * 2023-05-22 2023-06-23 广讯检测（广东）有限公司 Preparation method of epoxy-acrylic resin modified superfine azo-dicarboxamide and emulsion thereof

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4297974B2 (en) * 2007-10-16 2009-07-15 松本油脂製薬株式会社 Thermally expansible microspheres, production method and use thereof
US20110123807A1 (en) * 2009-11-25 2011-05-26 Cheil Industries Inc. Thermally-Expandable Microspheres Having Good Foaming Characteristics and Uniform Microsphere Diameter and Methods of Preparing the Same
CN104379647A (en) * 2012-09-04 2015-02-25 西能化工科技(上海)有限公司 Heat-expandable microspheres, preparation method and use thereof
CN108047480A (en) * 2017-12-05 2018-05-18 山东瑞丰高分子材料股份有限公司 High-temperature expansion polymer microballoon and preparation method thereof

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4297974B2 (en) * 2007-10-16 2009-07-15 松本油脂製薬株式会社 Thermally expansible microspheres, production method and use thereof
US20110123807A1 (en) * 2009-11-25 2011-05-26 Cheil Industries Inc. Thermally-Expandable Microspheres Having Good Foaming Characteristics and Uniform Microsphere Diameter and Methods of Preparing the Same
CN104379647A (en) * 2012-09-04 2015-02-25 西能化工科技(上海)有限公司 Heat-expandable microspheres, preparation method and use thereof
CN108047480A (en) * 2017-12-05 2018-05-18 山东瑞丰高分子材料股份有限公司 High-temperature expansion polymer microballoon and preparation method thereof

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114773693A (en) * 2022-04-12 2022-07-22 达州市嘉源体育用品有限公司 Rubber foaming sole
TWI796264B (en) * 2022-07-15 2023-03-11 正崴精密工業股份有限公司 Anti-extend-burn and flame-retardant material
CN115260877A (en) * 2022-08-02 2022-11-01 广东希贵光固化材料有限公司 UV temporary protective coating for heating film fading and application thereof
CN116284949A (en) * 2023-05-22 2023-06-23 广讯检测（广东）有限公司 Preparation method of epoxy-acrylic resin modified superfine azo-dicarboxamide and emulsion thereof

Similar Documents

Publication Publication Date Title
CN113801369A (en) Polymer foaming microsphere and preparation method and application thereof
JP5805607B2 (en) Thermally expandable microcapsules and uses thereof
CA1156399A (en) Process for preparing styrenic polymer particles
CN108912384B (en) Ultrahigh-temperature expandable thermoplastic microspheres and preparation method and application thereof
KR20150024817A (en) Microspheres
CN102812101A (en) Thermally expandable microcapsule
CN110698721B (en) Polymethacrylimide thermal expansion microsphere and preparation method thereof
EP2554619B1 (en) Thermally expandable microcapsule and process for production of thermally expandable microcapsule
WO2010052972A1 (en) Thermally expandable microcapsule and foam-molded article
KR20110058095A (en) Heat-expandable microparticles having good expandability and even particle diameter
CN107602769B (en) Method for synthesizing MBS resin
KR20200038540A (en) Thermally expandable microspheres made from bio-based monomers
SE2051007A1 (en) Heat-expandable microspheres and application thereof
CN111073028B (en) Inorganic material modified microcapsule and preparation method and application thereof
CN111111573A (en) Ultrasonic thermal expansion microcapsule and preparation method thereof
CN108912383B (en) Ultrahigh-temperature expandable thermoplastic microspheres and application thereof
CN110606976A (en) Preparation method of polymethacrylimide foam material
CN112980042A (en) Preparation method of high-temperature-resistant thermal expansion foaming microspheres and obtained product
EP3441439B1 (en) Microsphere, thermally foamable resin composition, foam molded body and manufacturing method for same
CN111218023B (en) Conductive thermal expansion microsphere with good flame retardance and preparation method thereof
US10150849B2 (en) Thermally-expandable microspheres, and composition and molded article containing same
JP5559585B2 (en) Vinyl chloride hollow particles, method for producing the same, vinyl chloride resin composition, and vinyl chloride molded article
EP1564276A1 (en) Heat-expandable microcapsules
JP5358074B2 (en) Microcapsule, resin composition for coating film formation, coating film and method for producing microcapsule
CN114672063B (en) Modified thermoplastic hollow polymer microsphere and preparation method thereof

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
WD01 Invention patent application deemed withdrawn after publication
WD01 Invention patent application deemed withdrawn after publication

Application publication date: 20211217