CN108084483B - Special thermally expandable polymer microsphere for polyvinyl chloride resin foaming and preparation method thereof - Google Patents
Special thermally expandable polymer microsphere for polyvinyl chloride resin foaming and preparation method thereof Download PDFInfo
- Publication number
- CN108084483B CN108084483B CN201711266156.4A CN201711266156A CN108084483B CN 108084483 B CN108084483 B CN 108084483B CN 201711266156 A CN201711266156 A CN 201711266156A CN 108084483 B CN108084483 B CN 108084483B
- Authority
- CN
- China
- Prior art keywords
- weight
- foaming
- parts
- agent
- thermally expandable
- 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.)
- Active
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
-
- 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
- C08J2327/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers
- C08J2327/02—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers not modified by chemical after-treatment
- C08J2327/04—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers not modified by chemical after-treatment containing chlorine atoms
- C08J2327/06—Homopolymers or copolymers of vinyl chloride
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Manufacturing Of Micro-Capsules (AREA)
- Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
Abstract
The invention relates to a special thermal expandable polymer microsphere for polyvinyl chloride resin foaming and a preparation method thereof, belonging to expandable particles. The foaming agent is composed of a thermoplastic resin shell and a foaming agent encapsulated in the shell, an oil phase composition composed of a polymerizable monomer and a cross-linking agent is dispersed in a water phase dispersion composition, and the foaming agent is coated in situ through suspension polymerization reaction in the presence of the foaming agent to directly prepare a foaming agent-coated polymer microsphere; the oil phase composition is characterized by comprising a polymerizable monomer and a cross-linking agent, and also comprising a silane coupling agent, wherein the foaming agent is a mixture of isopentane, isooctane and n-octane; the core-shell structure is complete, the particle size distribution is uniform, and the coating efficiency of the foaming agent is high; and the shell polymer has good heat resistance, higher initial temperature during expansion, higher maximum expansion temperature, high foaming multiplying power and wider foam stabilizing temperature range, and the polyvinyl chloride resin is special thermally expandable polymer microspheres for foaming.
Description
Technical Field
The invention relates to a special thermally expandable polymer microsphere for polyvinyl chloride resin foaming and a preparation method thereof. Belonging to the group of expandable particles.
Background
The heat expandable polymer microsphere is a multifunctional foaming material with wide application. Is a spherical particle having an extremely small particle diameter and having a shell-core structure. The core of the microsphere is liquid low-boiling-point alkane, and the shell of the microsphere is a thermoplastic high-molecular polymer which has good air tightness and can prevent substances in the core from escaping. At normal temperature, the shell of the microsphere is hard and the particles are tiny. When heated, the shell material softens and the core material vaporizes to produce internal pressure, causing the microspheres to expand, when the heating temperature is above the glass transition temperature of the shell. The volume is increased significantly. The particle size of the microspheres before expansion is generally 5-100 mu m, and after expansion, the volume can be expanded to tens of times or even hundreds of times of the original volume; after cooling, the polymer shell does not retract, and the density of the microspheres can be 400-1200 kg/m3Reduced to 20-30 kg/m3Or smaller. When the temperature returns to the ambient temperature before heating, the volume of the microspheres remains in the expanded state. I.e. the expansion process of the microspheres is irreversible. Initiation of microsphere expansionThe temperature is referred to as Tstart and the temperature at which the microspheres expand to a maximum is referred to as Tmax.
The heat-expandable polymer microspheres have good foaming performance due to the special structure of the heat-expandable polymer microspheres. When used for foaming thermoplastic resins. Compared with a simple gas foaming process, the foaming process has the characteristics of proper foaming temperature, wide foam stabilizing range, high foaming multiplying power, no rebound after cooling, bright and white color, no toxicity, no odor and the like. Is widely used for foaming processing of thermoplastic resin, rubber or thermoplastic elastomer. And endows the foaming product with better processing performance, and further improves the elasticity and the rebound resilience of the foaming product.
Polyvinyl chloride resin is one of five general-purpose plastics, and its yield is second only to polyethylene. PVC has excellent performances of flame retardance, wear resistance, insulation and the like, and is widely applied to the fields of light industry, agriculture, building materials, packaging, daily life, public utilities, electric power and the like.
The polyvinyl chloride foam material has the advantages of light weight, high specific strength, good heat and sound insulation, good buffering and damping effects, low thermal conductivity, easy mechanical processing, weldability, high flame retardance, good chemical reagent resistance, corrosion resistance, moisture resistance, surface coloring, printing and film coating, and good weather resistance.
However, the foaming process of polyvinyl chloride resin requires a higher temperature. Generally at 170-220 ℃. And the operation time lasts longer. Therefore, when the thermally expandable polymeric microspheres are used in the foaming process of polyvinyl chloride resin, it is desirable that the thermally expandable polymeric microspheres themselves have a higher initial temperature at which the microspheres begin to expand (Tstart value), and in many cases a higher temperature at which the microspheres expand to a maximum (Tmax value).
In addition, the polyvinyl chloride resin is foamed by adopting a common chemical method, the foaming ratio can only reach 20 times, and the increase is very difficult.
In the prior art, the high-temperature heat expandable polymer microspheres suitable for the foaming processing of polyvinyl chloride resin are not common.
Suspension polymerization has the advantages of good heat transfer, easy product separation, less impurities and the like. The method is widely used for producing resins such as polyvinyl chloride, polystyrene, PMMA, VDC copolymer and the like. The suspension polymerization method for preparing heat-expandable microspheres is also a commonly used polymerization method.
However, in the prior art, the heat-expandable polymer microspheres prepared by the suspension polymerization method have the following defects, and the heat-expandable polymer microspheres suitable for the foaming processing of polyvinyl chloride resin are difficult to prepare:
1. the particle size distribution is not uniform.
The thermoplastic resin shell polymer of the thermal expandable polymer microsphere has poor heat resistance, so that the thermal expandable microsphere is easy to yellow and crack in the resin foaming process.
3. The core-structure is incomplete, and the coating rate of the foaming agent is low.
5. The heat resistance of the product is not good enough. The foaming temperature is 140-170 ℃.
6. The expansion multiplying power is low, and the temperature range of the foam stabilization is not wide enough.
7. The suspension polymerization reaction time in the prior art is as long as 20 hours, so that the particle size distribution of the product is not uniform, and the coating rate of the foaming agent is low. But also increases the production cost.
The core-shell structure is complete, the particle size distribution is uniform, and the coating efficiency of the foaming agent is high; and the shell polymer has good heat resistance, higher initial temperature during expansion, higher maximum expansion temperature, high foaming ratio and wider foam stabilizing temperature range, and is expected to be suitable for processing the thermal expandable polymer microsphere foaming agent by foaming polyvinyl chloride resin.
Disclosure of Invention
The invention aims to avoid the defects in the prior art and provide the heat expandable polymer microspheres which are suitable for the polyvinyl chloride resin foaming processing technology, have high foaming multiplying power and wide foam stabilizing temperature range.
The invention also aims to provide a foaming agent which has complete core-shell structure, uniform particle size distribution and high foaming agent coating efficiency; and the shell polymer has good heat resistance, and is suitable for the preparation method of the heat-expandable polymer microspheres of the polyvinyl chloride resin foaming processing technology.
The object of the invention can be achieved by the following measures:
the invention relates to a special thermally expandable polymer microsphere for foaming polyvinyl chloride resin, which consists of a thermoplastic resin shell and a foaming agent encapsulated in the shell, wherein an oil phase composition consisting of a polymerizable monomer, a cross-linking agent and an initiator is dispersed in a water phase dispersion composition, and the foaming agent is coated in situ by suspension polymerization reaction in the presence of the foaming agent to directly prepare the foaming agent-coated polymer microsphere; the method is characterized in that:
the polymerizable monomer in the oil phase composition consists of acrylonitrile, methacrylonitrile, methyl methacrylate, butyl methacrylate, styrene, 1-dichloroethylene, methacrylic acid and acrylic acid;
the oil phase composition comprises a polymerizable monomer and a cross-linking agent, and also comprises a silane coupling agent component;
the foaming agent is a mixture of isopentane, isooctane and n-octane;
the water phase dispersion composition comprises a dispersion auxiliary agent component consisting of deionized water, sodium chloride, silica sol and a dispersant and a dispersion stabilizer component prepared from absolute ethyl alcohol, hydrazine hydrate and sodium citrate;
controlling the pH value of the aqueous phase dispersion composition system to be 2.9-3.1;
the special thermally expandable polymer microspheres for polyvinyl chloride resin foaming achieve the following technical indexes:
the excellent expansion performance of the special thermally expandable polymer microsphere for foaming polyvinyl chloride resin provided by the invention depends on the good barrier property of the shell polymer to the inner core foaming agent and the sufficient expansion internal pressure provided by the foaming agent with a reasonable formula. The pressure generated by the inner core is properly compatible with the thermoplasticity of the shell, so that the microsphere of the invention has good expansion performance and obtains ideal technical effect.
Firstly, the polymerizable monomer in the oil phase composition consists of acrylonitrile, methacrylonitrile, methyl methacrylate, butyl methacrylate, styrene, 1-dichloroethylene, methacrylic acid and acrylic acid;
the acrylonitrile monomer has good heat resistance and crystallization performance; hydrogen bonds in the molecular structure of acrylonitrile enable the permeation coefficient of a film layer obtained by polymerization to be small; the copolymer with the participation of the 1, 1-dichloroethylene in the formula has lower permeability, and can endow the shell polymer with good air tightness, so that the polymer formed by the two has excellent barrier property and air tightness;
methacrylonitrile, methyl methacrylate and butyl methacrylate can improve the thermoplasticity of the copolymer; the styrene can improve the heat resistance and pressure resistance of the microspheres;
methacrylic acid and acrylic acid have high crystallinity and high glass transition temperature, and participate in copolymerization to raise the softening temperature of the polymer. The acrylonitrile copolymer is used for making up the defect that the acrylonitrile component has good heat resistance but poor high-temperature elasticity.
The methacrylonitrile, the methyl methacrylate and the butyl methacrylate play a role in controlling the polymerization rate and have the function of improving the toughness of the polymer shell by controlling the elastic elongation and the softening point temperature of the polymer.
The addition of the cross-linking agent can increase the material strength of the shell polymer in high elastic state and viscous state, and improve the expansibility and heat resistance of the microsphere. The oil phase composition of the invention comprises a silane coupling agent component besides a polymerizable monomer and a cross-linking agent; the cross-linking agent and the coupling agent have linear copolymerization points, and the elastic range of the copolymer can be further expanded and the heat-resistant stability of the copolymer can be improved through the cross-linking and coupling reaction of the polymer, so that the invention makes an important technical contribution to the completion of the task of the invention.
The foaming agent adopted by the invention is a mixture of isopentane, isooctane and n-octane, and the boiling point and the preferable composition range of the foaming agent provide proper expansion temperature and expansion pressure for the thermally expandable polymer microspheres special for foaming the polyvinyl chloride resin. Makes technical contribution to the preparation of the polyurethane foam with good expansion performance and larger foaming ratio.
The aqueous phase dispersion composition comprises a dispersion auxiliary agent component consisting of deionized water, sodium chloride, silica sol and a dispersing agent and a dispersion stabilizer component prepared from absolute ethyl alcohol, hydrazine hydrate and sodium citrate; is an important component in the technical scheme of the invention. The inventor of the invention finds in experiments that the microsphere particles prepared by the aqueous phase dispersion auxiliary composition are spherical with better uniformity under a microscope, and the dispersion stabilizer prepared by absolute ethyl alcohol, hydrazine hydrate and sodium citrate is adopted, so that after the monomer reaction is finished, the filtration is easy, the separation is convenient, the microsphere particles are better, the reaction time can be shortened from the original 20 hours to 10-12 hours, and the reaction time is shortened.
The pH of the aqueous phase dispersion composition system is controlled to be 2.9-3.1; is a preferable technical proposal.
The object of the invention is also achieved by the following measures:
the invention relates to a special thermally expandable polymer microsphere for polyvinyl chloride resin foaming, wherein a polymerizable monomer comprises the following raw materials in percentage by mass:
the addition amount of the cross-linking agent is 0.1 to 0.5 percent of the total mass of the polymerized monomers;
the adding amount of the silane coupling agent is 2-5% of the total mass of the polymerized monomers.
Is a preferable technical proposal.
The invention relates to a special thermally expandable polymer microsphere for polyvinyl chloride resin foaming, wherein a polymerizable monomer comprises the following raw materials in percentage by mass:
the addition amount of the cross-linking agent is 0.2 to 0.4 percent of the total mass of the polymerized monomers;
the adding amount of the silane coupling agent is 3-4% of the total mass of the polymerized monomers.
Is a further preferable technical proposal.
The invention relates to a special thermally expandable polymer microsphere for polyvinyl chloride resin foaming, wherein a polymerizable monomer comprises the following raw materials in percentage by mass:
the addition amount of the cross-linking agent is 0.3 percent of the total mass of the polymerized monomers;
the adding amount of the silane coupling agent is 3.7 percent of the total mass of the polymerized monomers.
Is a preferable technical proposal.
The silane coupling agent in the oil phase composition is one of KH550, KH560, KH570, KH792, DL602 and DL 171.
The cross-linking agent is one of Ethylene Glycol Dimethacrylate (EGDMA), trimethylolpropane trimethacrylate (TMPTMA), polyethylene glycol 400 dimethacrylate (PEG400DMA) and 1, 6 hexanediol dimethacrylate (HDDMA).
The initiator adopted in the suspension polymerization reaction is one of di- (2-ethylhexyl) peroxydicarbonate and 2, 2' -azobisisobutyronitrile or a composition of the two.
The invention relates to a special thermally expandable polymer microsphere for polyvinyl chloride resin foaming, which comprises the following raw materials in percentage by mass:
75-90% of isopentane
5 to 25% of isooctane
5-25% of n-octane.
Is a preferred compositional range.
The foaming agent is added into the special thermally expandable polymer microspheres for foaming the polyvinyl chloride resin, and the adding amount of the foaming agent is 12-35% of the total mass of the polymerized monomers. Is a preferable technical proposal.
The foaming agent is added into the special thermally expandable polymer microspheres for foaming the polyvinyl chloride resin, and the adding amount of the foaming agent is 20-30% of the total mass of the polymerized monomers. Is the most preferred technical scheme.
The dispersing auxiliary component of the special thermally expandable polymer microsphere for foaming the polyvinyl chloride resin comprises the following raw materials in parts by mass
The dispersing agent of the thermally expandable polymer microsphere special for polyvinyl chloride resin foaming is polyvinylpyrrolidone or polyvinyl alcohol, which is a preferable technical scheme.
The invention relates to a special thermally expandable polymer microsphere for polyvinyl chloride resin foaming, wherein a dispersion stabilizer of an aqueous dispersion composition comprises the following raw materials in parts by weight:
1.7-20% of absolute ethyl alcohol
1.7-20 wt% hydrazine hydrate aqueous solution
1.7 to 20 wt% of a citric acid aqueous solution.
Is a preferable technical proposal.
The preparation method of the special thermally expandable polymer microspheres for polyvinyl chloride resin foaming is characterized by comprising the following steps of:
preparation of aqueous dispersion composition
Preparation of aqueous solution of raw material
a. Preparation of dispersant solution
Adding 0.12-1 part by weight of dispersant into 160 parts by weight of deionized water, dissolving and stirring uniformly for later use;
b. preparation of aqueous phase polymerization inhibitor solution
Adding 36-120 parts by weight of sodium chloride into 350 parts by weight of deionized water, and dissolving for later use;
c. preparation of dispersing assistant sodium nitrite aqueous solution
Preparing 1 wt% sodium nitrite aqueous solution with deionized water for later use;
d. preparation of aqueous hydrazine hydrate solution
Preparing 1 wt% hydrazine hydrate aqueous solution with deionized water for later use;
e. preparation of aqueous citric acid solution
Preparing 1 wt% citric acid aqueous solution with deionized water for later use;
preparation of dispersing assistant component
Fully and uniformly mixing 1.70-10 parts by weight of the dispersant solution prepared in the item a, the aqueous phase polymerization inhibitor solution prepared in the item b and 1 wt% of sodium nitrite aqueous solution prepared in the item c in a mixing and stirring tank, slowly dropwise adding 8-32 parts by weight of commercially available 20 wt% silica sol solution under stirring, and stirring and mixing for 15 minutes to prepare a dispersing aid component for later use;
preparation of Dispersion stabilizer component
Stirring and mixing 1.7-20 parts by weight of absolute ethyl alcohol, 1.7-20 parts by weight of 1 wt% hydrazine hydrate aqueous solution prepared in the step d and 1.7-20 parts by weight of 1 wt% citric acid aqueous solution prepared in the step e uniformly to prepare a dispersion stabilizer component for later use;
preparation of aqueous dispersion composition
Adding the dispersion stabilizer component prepared in the third step into the aqueous phase dispersion auxiliary agent composition prepared in the first step, fully stirring, and uniformly mixing and dispersing to prepare an aqueous phase dispersion composition for later use;
preparation of oil phase composition
Mixing 25-74 parts by weight of acrylonitrile, 2-15 parts by weight of methacrylonitrile, 5-40 parts by weight of methyl methacrylate, 2-8 parts by weight of butyl methacrylate, 2-15 parts by weight of styrene, 3-30 parts by weight of 1, 1-dichloroethylene, 5-30 parts by weight of methacrylic acid, 2-10 parts by weight of acrylic acid, 0.1-0.5 part by weight of a cross-linking agent and 2-5 parts by weight of a silane coupling agent to form a shell raw material component of the thermally expandable polymer microsphere special for polyvinyl chloride resin foaming; sequentially adding 9.0-31.5 parts by weight of isopentane and 0.6-8.75 parts by weight of isooctane in sequence; 0.6-8.75 parts by weight of n-octane; 0.1-2.0 parts by weight of initiator, and mixing and dissolving to prepare an oily composition;
thirdly, mixing, homogenizing and dispersing
Putting the water phase dispersed composition prepared in the step one and the oil phase composition prepared in the step two into a homomixer, and controlling the diameter of oil phase liquid drops dispersed in the water phase to be 5-50 microns through the homomixer in a rotating speed of 2000-10000 r/min;
polymerization
Putting the suspension liquid qualified by the third step of homogeneous dispersion into a polymerization kettle, replacing with nitrogen, maintaining the pressure at 0.15-2 MPa, slowly heating to 45-75 ℃ to start reaction, and reacting for 10-12 hours under uniform stirring;
fifthly, filtering, washing and drying
And step four, carrying out suction filtration on the polymerization product, washing a filter cake with deionized water, drying in an oven, crushing and sieving to obtain the special thermally expandable polymer microspheres for foaming the polyvinyl chloride resin.
The invention discloses application of special thermally expandable polymer microspheres for polyvinyl chloride resin foaming, which is characterized in that the thermally expandable polymer microspheres are used as foaming agents for producing foaming materials of the polyvinyl chloride resin, polystyrene resin, polyethylene resin, polypropylene resin, thermoplastic polyurethane and phenolic resin.
Compared with the prior art, the special thermally expandable polymer microsphere for foaming polyvinyl chloride resin and the preparation method thereof can produce the following positive effects:
1. the core-shell structure is complete, the particle size distribution is uniform, and the coating efficiency of the foaming agent is high; and the shell polymer has good heat resistance, higher initial temperature during expansion, higher maximum expansion temperature, high foaming ratio and wider foam stabilizing temperature range, and is suitable for the special heat-expandable polymer microspheres for foaming polyvinyl chloride resin applied to the foaming processing technology of thermoplastic resin, rubber or thermoplastic elastomer.
2. The core-shell structure is complete, the particle size distribution is uniform, and the coating efficiency of the foaming agent is high; and the shell polymer has good heat resistance, higher initial temperature during expansion, higher maximum expansion temperature, high foaming ratio and wider foam stabilizing temperature range, and is suitable for the preparation method of the special thermally expandable polymer microspheres for foaming polyvinyl chloride resin applied to the foaming processing technology of thermoplastic resin, rubber or thermoplastic elastomer.
3. Solves the technical problem of uneven particle size distribution of the thermally expandable polymer microsphere product. The average particle size of the prepared special thermally expandable polymer microspheres for polyvinyl chloride resin foaming is 5-60 mu m. The preferable scheme is 5-15 mu m.
4. The heat resistance of the thermoplastic resin shell polymer of the heat expandable polymer microsphere is improved, the initial expansion temperature is 135-190 ℃, and the maximum expansion temperature is 220-245 ℃.
5. Solves the technical problem that the thermally expandable microspheres are easy to yellow and crack in the resin foaming process. The yellowing-free time at 220 ℃ is more than or equal to 15 minutes; the non-cracking time at 220 ℃ is more than or equal to 20 minutes. The whiteness% of the product is more than or equal to 90%.
6. The microsphere core-structure is complete, and the internal encapsulation rate of the foaming agent is more than or equal to 95 percent.
7. The expansion multiplying power is greatly improved to 90-120.
And 8. the suspension polymerization reaction time is shortened to 10-12 hours from the original 20 hours. The production cost is reduced.
Detailed Description
The invention will be further described in detail with reference to the following examples:
examples 1 to 12
The thermally expandable polymer microspheres specially used for foaming polyvinyl chloride resin are prepared according to the following steps
Preparation of aqueous dispersion composition
Preparation of aqueous solution of raw material
a. Preparation of dispersant solution
Adding 0.12-1 part by weight of dispersant into 160 parts by weight of deionized water, dissolving and stirring uniformly for later use;
b. preparation of aqueous phase polymerization inhibitor solution
Adding 36-120 parts by weight of sodium chloride into 350 parts by weight of deionized water, and dissolving for later use;
c. preparation of dispersing assistant sodium nitrite aqueous solution
Preparing 1 wt% sodium nitrite aqueous solution with deionized water for later use;
d. preparation of aqueous hydrazine hydrate solution
Preparing 1 wt% hydrazine hydrate aqueous solution with deionized water for later use;
e. preparation of aqueous citric acid solution
Preparing 1 wt% citric acid aqueous solution with deionized water for later use;
preparation of dispersing assistant component
Fully and uniformly mixing 1.70-10 parts by weight of the dispersant solution prepared in the item a, the aqueous phase polymerization inhibitor solution prepared in the item b and 1 wt% sodium nitrite aqueous solution prepared in the item c in a mixing and stirring tank, slowly dropwise adding 8-32 parts by weight of commercially available 20 wt% silica sol solution under stirring, and stirring and mixing for 15 minutes to prepare a dispersing aid component for later use;
preparation of Dispersion stabilizer component
Stirring and mixing 1.7-20 parts by weight of absolute ethyl alcohol, 1.7-20 parts by weight of 1 wt% hydrazine hydrate aqueous solution prepared in the step d and 1.7-20 parts by weight of 1 wt% citric acid aqueous solution prepared in the step e uniformly to prepare a dispersion stabilizer component for later use;
preparation of aqueous dispersion composition
Adding the dispersion stabilizer component prepared in the third step into the aqueous phase dispersion auxiliary agent composition prepared in the first step, fully stirring, and uniformly mixing and dispersing to prepare an aqueous phase dispersion composition for later use;
preparation of oil phase composition
Mixing 25-74 parts by weight of acrylonitrile, 2-15 parts by weight of methacrylonitrile, 5-40 parts by weight of methyl methacrylate, 2-8 parts by weight of butyl methacrylate, 2-15 parts by weight of styrene, 3-30 parts by weight of 1, 1-dichloroethylene, 5-30 parts by weight of methacrylic acid, 2-10 parts by weight of acrylic acid, 0.1-0.5 part by weight of a cross-linking agent and 2-5 parts by weight of a silane coupling agent to form a shell raw material component of the thermally expandable polymer microsphere special for polyvinyl chloride resin foaming; sequentially adding 9.0-31.5 parts by weight of isopentane and 0.6-8.75 parts by weight of isooctane in sequence; 0.6-8.75 parts by weight of n-octane; 0.1-2.0 parts by weight of initiator, and mixing and dissolving to prepare an oily composition;
thirdly, mixing, homogenizing and dispersing
Putting the water phase dispersed composition prepared in the step one and the oil phase composition prepared in the step two into a homomixer, and controlling the diameter of oil phase liquid drops dispersed in the water phase to be 5-50 microns through the homomixer in a rotating speed of 2000-10000 r/min;
polymerization
Putting the suspension liquid qualified by the third step of homogeneous dispersion into a polymerization kettle, replacing with nitrogen, maintaining the pressure at 0.15-2 MPa, slowly heating to 45-75 ℃ to start reaction, and reacting for 10-12 hours under uniform stirring;
fifthly, filtering, washing and drying
And step four, carrying out suction filtration on the polymerization product, washing a filter cake with deionized water, drying in an oven, crushing and sieving to obtain the special thermally expandable polymer microspheres for foaming the polyvinyl chloride resin.
The raw material ratios of examples 1 to 12 in parts by weight are listed in table 1, and the technical indexes of the thermally expandable polymer microspheres specially used for foaming the polyvinyl chloride resin prepared in examples 1 to 12 are listed in table 2
Table 1 examples 1 to 12 raw material ratios in parts by mass
TABLE 2 technical indexes of thermally expandable polymer microspheres specially used for foaming polyvinyl chloride resin prepared in examples 1 to 12
Description of blowing agent retention:
1. defining: in the present invention, the percentage of the inclusion rate of the foaming agent at the temperature during thermal expansion with respect to the inclusion rate of the foaming agent encapsulated in the thermally expandable microspheres before thermal expansion is defined as the retention rate of the foaming agent at the test temperature.
2. The test method comprises the following steps: the heat-expandable microspheres Wr (g) were placed in an aluminum plate having an outer diameter of 5.2mm, heated from 20 ℃ to 80 ℃ at a heating rate of 10 ℃/min, and kept at 80 ℃ for 30min to remove water contained in the heat-expandable microspheres, thereby confirming that the weight change was constant. The weight Ws (g) at Tav (. degree.C.) was measured by heating from 80 ℃ to 300 ℃ at a temperature-raising rate of 10 ℃/min. The amount CR3 (wt%) of the blowing agent released from the thermally-expansible microballs was calculated by the following calculation formula (G), and the blowing agent retention Rb (%) was calculated by the following calculation formula (H).
The retention of the foaming agent at the time of thermal expansion was evaluated based on Rb (%) according to the following criteria. The instrument used was a differential type differential thermal scale.
((Wr-Ws)/Wr×100)-CW＝CR3(G)
Rb＝(CR2-CR3)/CR2(H)
Method for measuring foaming ratio of microspheres
Drying and crushing the product, firstly measuring apparent density, then filling 0.5g of heat-expandable microspheres into a 50ml test tube, uniformly spreading, placing the test tube into an oven, then heating the sample at the temperature rising rate of 10 ℃/min within the range of 20-200 ℃, taking the initial expansion temperature as start when the microsphere volume is observed to start changing, taking the temperature when the expansion surface reaches the maximum expansion scale as the maximum expansion temperature, and calculating the expansion ratio according to the initial apparent density, mass and volume when the expansion surface reaches the maximum expansion scale.
Claims (10)
1. A special thermal expandable polymer microsphere for polyvinyl chloride resin foaming consists of a thermoplastic resin shell and a foaming agent encapsulated in the shell, wherein an oil phase composition consisting of a polymerizable monomer, a cross-linking agent and an initiator is dispersed in a water phase dispersion composition, and the foaming agent is coated in situ by suspension polymerization reaction in the presence of the foaming agent to directly prepare the foaming agent-coated polymer microsphere; the method is characterized in that:
the polymerizable monomer in the oil phase composition consists of acrylonitrile, methacrylonitrile, methyl methacrylate, butyl methacrylate, styrene, 1-dichloroethylene, methacrylic acid and acrylic acid;
the oil phase composition comprises a polymerizable monomer and a cross-linking agent, and also comprises a silane coupling agent component;
the foaming agent is a mixture of isopentane, isooctane and n-octane;
the water phase dispersion composition comprises a dispersion auxiliary agent component consisting of deionized water, sodium chloride, sodium nitrite, silica sol and a dispersing agent and a dispersion stabilizer component prepared from absolute ethyl alcohol, hydrazine hydrate and sodium citrate;
controlling the pH value of the aqueous phase dispersion composition system to be 2.9-3.1;
the preparation method of the special thermally expandable polymer microspheres for polyvinyl chloride resin foaming comprises the following steps:
preparation of aqueous dispersion composition
Preparation of aqueous solution of raw material
a. Preparation of dispersant solution
Adding 0.12-1 part by weight of dispersant into 160 parts by weight of deionized water, dissolving and stirring uniformly for later use;
b. preparation of aqueous phase polymerization inhibitor solution
Adding 36-120 parts by weight of sodium chloride into 350 parts by weight of deionized water, and dissolving for later use;
c. preparation of dispersing assistant sodium nitrite aqueous solution
Preparing 1 wt% sodium nitrite aqueous solution with deionized water for later use;
d. preparation of aqueous hydrazine hydrate solution
Preparing 1 wt% hydrazine hydrate aqueous solution with deionized water for later use;
e. preparation of aqueous citric acid solution
Preparing 1 wt% citric acid aqueous solution with deionized water for later use;
preparation of dispersing assistant component
Fully and uniformly mixing 1.70-10 parts by weight of the dispersant solution prepared in the item a, the aqueous phase polymerization inhibitor solution prepared in the item b and 1 wt% sodium nitrite aqueous solution prepared in the item c in a mixing and stirring tank, slowly dropwise adding 8-32 parts by weight of 20 wt% silica sol solution under stirring, and stirring and mixing for 15 minutes to prepare a dispersing aid component for later use;
preparation of Dispersion stabilizer component
Stirring and mixing 1.7-20 parts by weight of absolute ethyl alcohol, 1.7-20 parts by weight of 1 wt% hydrazine hydrate aqueous solution prepared in the step d and 1.7-20 parts by weight of 1 wt% citric acid aqueous solution prepared in the step e uniformly to prepare a dispersion stabilizer component for later use;
preparation of aqueous dispersion composition
Adding the dispersion stabilizer component prepared in the third step into the aqueous phase dispersion auxiliary agent composition prepared in the first step, fully stirring, and uniformly mixing and dispersing to prepare an aqueous phase dispersion composition for later use;
preparation of oil phase composition
Mixing 25-74 parts by weight of acrylonitrile, 2-15 parts by weight of methacrylonitrile, 5-40 parts by weight of methyl methacrylate, 2-8 parts by weight of butyl methacrylate, 2-15 parts by weight of styrene, 3-30 parts by weight of 1, 1-dichloroethylene, 5-30 parts by weight of methacrylic acid, 2-10 parts by weight of acrylic acid, 0.1-0.5 part by weight of a cross-linking agent and 2-5 parts by weight of a silane coupling agent to form a shell raw material component of the thermally expandable polymer microsphere special for polyvinyl chloride resin foaming; sequentially adding 9.0-31.5 parts by weight of isopentane and 0.6-8.75 parts by weight of isooctane in sequence; 0.6-8.75 parts by weight of n-octane; 0.1-2.0 parts by weight of initiator, and mixing and dissolving to prepare an oily composition;
thirdly, mixing, homogenizing and dispersing
Putting the water phase dispersed composition prepared in the step one and the oil phase composition prepared in the step two into a homomixer, and controlling the diameter of oil phase liquid drops dispersed in the water phase to be 5-50 microns through the homomixer in a rotating speed of 2000-10000 r/min;
polymerization
Putting the suspension liquid qualified by the third step of homogeneous dispersion into a polymerization kettle, replacing with nitrogen, maintaining the pressure at 0.15-2 MPa, slowly heating to 45-75 ℃ to start reaction, and reacting for 10-12 hours under uniform stirring;
fifthly, filtering, washing and drying
And step four, carrying out suction filtration on the polymerization product, washing a filter cake with deionized water, drying in an oven, crushing and sieving to obtain the special thermally expandable polymer microspheres for polyvinyl chloride resin foaming:
the special thermally expandable polymer microspheres for polyvinyl chloride resin foaming achieve the following technical indexes:
2. the thermally expandable polymeric microspheres, which are exclusively used for foaming polyvinyl chloride resin according to claim 1, wherein the polymerizable monomer comprises the following raw materials in mass percent, and the sum of the mass fractions is 100%:
the addition amount of the cross-linking agent is 0.2 to 0.4 percent of the total mass of the polymerized monomers;
the adding amount of the silane coupling agent is 3-4% of the total mass of the polymerized monomers.
3. The thermally expandable polymeric microspheres, which are exclusively used for foaming polyvinyl chloride resin according to claim 1, wherein the polymerizable monomer comprises the following raw materials in percentage by mass:
the addition amount of the cross-linking agent is 0.3 percent of the total mass of the polymerized monomers;
the adding amount of the silane coupling agent is 3.7 percent of the total mass of the polymerized monomers.
4. Thermally expandable polymeric microspheres according to claim 1, wherein the silane coupling agent in the oil phase composition is one of KH550, KH560, KH570, KH792, DL602, DL 171.
5. The thermally expandable polymeric microspheres as claimed in claim 1, wherein the cross-linking agent is one of ethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, polyethylene glycol 400 dimethacrylate, and 1, 6-hexanediol dimethacrylate.
6. Thermally expandable polymeric microspheres as claimed in claim 1, wherein the initiator used in the suspension polymerization is selected from bis- (2-ethylhexyl) peroxydicarbonate, 2' -azobisisobutyronitrile, or a combination thereof.
7. The thermally expandable polymeric microspheres, which are exclusively used for foaming polyvinyl chloride resin according to claim 1, wherein the foaming agent comprises the following raw materials in percentage by mass, and the sum of the mass fractions is 100%:
75-90% of isopentane
5 to 25% of isooctane
5-25% of n-octane.
8. The thermally expandable polymeric microspheres of claim 1, wherein the amount of said blowing agent added is from 12% to 35% of the total mass of the polymerized monomers.
9. The thermally expandable polymeric microspheres of claim 1, wherein the amount of said blowing agent added is 20 to 30% of the total mass of the polymerized monomers.
10. Thermally expandable polymeric microspheres according to claim 9, especially for polyvinyl chloride resin foaming, characterized in that said dispersing agent is polyvinylpyrrolidone or polyvinyl alcohol.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711266156.4A CN108084483B (en) | 2017-12-05 | 2017-12-05 | Special thermally expandable polymer microsphere for polyvinyl chloride resin foaming and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711266156.4A CN108084483B (en) | 2017-12-05 | 2017-12-05 | Special thermally expandable polymer microsphere for polyvinyl chloride resin foaming and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108084483A CN108084483A (en) | 2018-05-29 |
| CN108084483B true CN108084483B (en) | 2020-11-27 |
Family
ID=62173694
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711266156.4A Active CN108084483B (en) | 2017-12-05 | 2017-12-05 | Special thermally expandable polymer microsphere for polyvinyl chloride resin foaming and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108084483B (en) |
Families Citing this family (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108047480B (en) * | 2017-12-05 | 2020-11-27 | 山东瑞丰高分子材料股份有限公司 | High-temperature expanded polymer microsphere and preparation method thereof |
| EP3666518B1 (en) * | 2018-12-11 | 2023-09-27 | TMG - Tecidos Plastificados e Outros Revestimentos para a Indústria Automóvel, S.A. | Sheet structures containing natural polymers and microspheres |
| CN109721888A (en) * | 2018-12-30 | 2019-05-07 | 安徽科居新材料科技有限公司 | Wood plastic composite and preparation method thereof |
| CN111647235B (en) * | 2019-03-04 | 2022-04-01 | 合肥华凌股份有限公司 | Novel migration-resistant PVC sealing material and application thereof |
| CN110372924A (en) * | 2019-06-12 | 2019-10-25 | 李承忠 | A kind of composite rubber water stop |
| CN110591250B (en) * | 2019-09-12 | 2021-04-13 | 宁波东胜橡胶制品有限公司 | PVC (polyvinyl chloride) foam material for sports shock pad and preparation process thereof |
| CN110922631A (en) * | 2019-12-09 | 2020-03-27 | 苏州禾川化学技术服务有限公司 | Preparation method of physical thermal expansion high-molecular foaming agent |
| CN111087693A (en) * | 2019-12-25 | 2020-05-01 | 上海金发科技发展有限公司 | Low-density low-dielectric hydrophobic polypropylene composite material and preparation method thereof |
| CN113462095A (en) * | 2020-03-31 | 2021-10-01 | 快思瑞科技(上海)有限公司 | PVC foaming functional master batch and preparation method thereof |
| WO2022041978A1 (en) * | 2020-08-25 | 2022-03-03 | 浙江衢州巨塑化工有限公司 | Thermally expandable polyvinylidene chloride microsphere and preparation method therefor |
| CN112159547B (en) * | 2020-08-25 | 2022-04-22 | 浙江衢州巨塑化工有限公司 | Thermal expansion polyvinylidene chloride microsphere |
| CN112795049B (en) * | 2020-12-31 | 2023-02-07 | 运研材料科技（上海）有限公司 | Pre-foaming thermal expansion microsphere, preparation method and application thereof |
| CN112831082A (en) * | 2021-01-29 | 2021-05-25 | 高密浩翰木塑材料科技有限公司 | Production process of physical foaming agent for PVC foamed sole |
| CN113683923A (en) * | 2021-08-03 | 2021-11-23 | 万辉(广州)高新材料有限公司 | Liquid type foaming coating and preparation method and use method thereof |
| CN114369281B (en) * | 2021-12-28 | 2023-05-02 | 河北科技大学 | Thermal expansion type foaming microsphere and preparation method thereof |
| CN114752098A (en) * | 2022-04-12 | 2022-07-15 | 界首市锦丰塑业有限公司 | Plastic basin for flower planting and preparation method thereof |
| CN114773662B (en) * | 2022-05-05 | 2023-10-20 | 常州市宝丽胶粘剂有限公司 | Self-demolding reflective film surface layer resin and preparation method thereof |
| CN115165165B (en) * | 2022-06-24 | 2023-05-23 | 深圳深南电燃机工程技术有限公司 | High-sensitivity flexible pressure sensor |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102775550A (en) * | 2012-07-12 | 2012-11-14 | 西能化工科技(上海)有限公司 | Medium-high temperature thermal expansibility microsphere and method for reducing residual monomers therein |
| 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 |
-
2017
- 2017-12-05 CN CN201711266156.4A patent/CN108084483B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102775550A (en) * | 2012-07-12 | 2012-11-14 | 西能化工科技(上海)有限公司 | Medium-high temperature thermal expansibility microsphere and method for reducing residual monomers therein |
| 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 |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108084483A (en) | 2018-05-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108084483B (en) | Special thermally expandable polymer microsphere for polyvinyl chloride resin foaming and preparation method thereof | |
| CN108047480B (en) | High-temperature expanded polymer microsphere and preparation method thereof | |
| US11807717B2 (en) | Method of producing polyamide fine particles, and polyamide fine particles | |
| WO2014109413A1 (en) | Microcapsule heat storage material, production method thereof and use thereof | |
| WO2015085824A1 (en) | Vinylidene fluoride copolymer and preparation method therefor | |
| US8383693B2 (en) | Aerogel, and composition and method for manufacturing the aerogel | |
| CN112739778A (en) | Resin composition and molded article thereof | |
| CN105368150A (en) | Water-based weather-resistant glass printing ink | |
| JP4662804B2 (en) | Hollow resin fine particles, method for producing hollow resin fine particles, and composite material | |
| CN108341974A (en) | A kind of dynamic aggregation object and its application with hybrid cross-linked structure | |
| CN115322509B (en) | Composite Janus particle, manufacturing method thereof, coating and laminated body | |
| CN102911418B (en) | Method for preparing polyacrylate-organic P fire retardant through concentrated emulsion | |
| CN109908973B (en) | Preparation method of latex type interpenetrating network polymer cation exchange membrane | |
| KR20100002408A (en) | Thermoplastic resin | |
| CN114207019B (en) | PMMA-based casting polymers with improved mechanical properties | |
| CN106279569A (en) | A kind of organic silicon modified aqueous epoxy resin and preparation method thereof | |
| CN110709438B (en) | Process for preparing graft copolymers | |
| SA516380359B1 (en) | Water expandable polymer beads | |
| CN107151280A (en) | A kind of suspension method prepares the synthesis technique of polyvinyl chloride | |
| JP5535118B2 (en) | Hollow carbon particles and method for producing the same | |
| TWI476233B (en) | Spherical polymer beads and preparation method thereof | |
| CN110951185A (en) | Preparation method of polyvinyl chloride modified material | |
| CN110734514A (en) | transparent flame-retardant polyunsaturated phosphate and preparation method thereof | |
| KR20110034237A (en) | Spherical multi-layer large polymer particles with low density and preparation method thereof | |
| JP5358074B2 (en) | Microcapsule, resin composition for coating film formation, coating film and method for producing microcapsule |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |