WO2022127115A1 - 一种提高粉末涂料防腐蚀性能的方法 - Google Patents

一种提高粉末涂料防腐蚀性能的方法 Download PDF

Info

Publication number
WO2022127115A1
WO2022127115A1 PCT/CN2021/108523 CN2021108523W WO2022127115A1 WO 2022127115 A1 WO2022127115 A1 WO 2022127115A1 CN 2021108523 W CN2021108523 W CN 2021108523W WO 2022127115 A1 WO2022127115 A1 WO 2022127115A1
Authority
WO
WIPO (PCT)
Prior art keywords
powder
auxiliary agent
corrosion
coatings
coating
Prior art date
Application number
PCT/CN2021/108523
Other languages
English (en)
French (fr)
Inventor
祝京旭
张辉
Original Assignee
广东西敦千江粉漆科学研究有限公司
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 广东西敦千江粉漆科学研究有限公司 filed Critical 广东西敦千江粉漆科学研究有限公司
Publication of WO2022127115A1 publication Critical patent/WO2022127115A1/zh

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D5/00—Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes
    • C09D5/03—Powdery paints
    • C09D5/033—Powdery paints characterised by the additives
    • C09D5/038—Anticorrosion agents
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D133/00—Coating compositions based on 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 only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Coating compositions based on derivatives of such polymers
    • C09D133/04—Homopolymers or copolymers of esters
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D163/00—Coating compositions based on epoxy resins; Coating compositions based on derivatives of epoxy resins
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D167/00—Coating compositions based on polyesters obtained by reactions forming a carboxylic ester link in the main chain; Coating compositions based on derivatives of such polymers
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D175/00—Coating compositions based on polyureas or polyurethanes; Coating compositions based on derivatives of such polymers
    • C09D175/04—Polyurethanes
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D5/00—Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes
    • C09D5/08—Anti-corrosive paints
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D5/00—Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes
    • C09D5/08—Anti-corrosive paints
    • C09D5/082—Anti-corrosive paints characterised by the anti-corrosive pigment
    • C09D5/084—Inorganic compounds
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D5/00—Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes
    • C09D5/08—Anti-corrosive paints
    • C09D5/10—Anti-corrosive paints containing metal dust
    • C09D5/106—Anti-corrosive paints containing metal dust containing Zn
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/02—Elements
    • C08K3/08—Metals
    • C08K2003/0893—Zinc
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/32—Phosphorus-containing compounds
    • C08K2003/321—Phosphates
    • C08K2003/328—Phosphates of heavy metals
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K2201/00—Specific properties of additives
    • C08K2201/011—Nanostructured additives

Definitions

  • the invention relates to the field of preparation of polymer materials, in particular to a method for improving the anti-corrosion performance of powder coatings.
  • Solvent-based coatings are the mainstream products in the anti-corrosion and heavy-duty anti-corrosion coatings industry. During the manufacturing, construction, and curing process of traditional solvent-based coatings, a large amount of volatile organic compounds (VOCs) are volatilized into the air. Many widely used solvents are toxic and hazardous substances that are detrimental to the safety, health and environmental protection (HSE) of manufacturing processes, operators and the surrounding environment. In recent years, water-based coatings have made great progress in replacing solvent-based coatings. However, due to the constraints of slow drying, harsh construction temperature and humidity conditions, and high cost, they are still unable to replace solvent-based coatings on a large scale.
  • polyester polyethylene glycol dimethacrylate
  • epoxy epoxy
  • polyester/epoxy hybrid polyester/epoxy hybrid
  • polyurethane polyurethane
  • acrylic acrylic, namely acrylate
  • All five powder coating systems have certain anti-corrosion properties, especially epoxy powder coatings.
  • the ether bond on the main chain of epoxy resin is easily broken under ultraviolet (UV) irradiation in sunlight and cannot be used as an outdoor topcoat.
  • UV ultraviolet
  • the anti-corrosion performance of polyester powder coatings is slightly inferior to epoxy powder coatings, there is no problem of solar chalking; therefore, the above systems all have certain defects or limitations.
  • the purpose of the present invention is to provide a method for improving the anti-corrosion performance of powder coatings, by adding specific anti-corrosion additives, keeping the basis of the resin system in the existing powder coating formula unchanged, and greatly improving the anti-corrosion performance of powder coatings.
  • the present invention adopts the following technical solutions: a method for improving the anti-corrosion performance of powder coatings, comprising adding an anti-corrosion additive to the powder coating;
  • the anti-corrosion additive comprises a first additive, or a first additive
  • the first auxiliary agent includes nanometer clay;
  • the second adjuvant includes a combination of barrier pigments and inorganic salt antirust pigments;
  • the third adjuvant includes a combination of carbon nanotubes and derivatives thereof and metal powder with sacrificial anode function.
  • the method of adding special compound anti-corrosion additives to ordinary coatings is adopted, and the obtained powder coatings have higher anti-corrosion properties and wider application fields, including ordinary anti-corrosion and heavy-duty anti-corrosion.
  • the method of directly adding additives in the invention is more cost-effective and more versatile than changing the resin curing agent.
  • the present invention can also be applied to the sintered epoxy powder coating to further improve its anti-corrosion performance. What is particularly important is that the present invention has solved the problem of using a certain or a certain type of coating alone in some cases through detailed electrochemical characterization and mechanism research. In the case where additives cannot improve the anti-corrosion performance of powder coatings, in powder coating applications with high appearance requirements, ultra-fine powder coatings can be used without reducing the surface flatness, gloss, distinctness of image (DOI) and other indicators of the coating. Significantly reduce the thickness of the coating film, thereby reducing the cost of use.
  • DOI distinctness of image
  • the formulation of the anti-corrosion additive in the present invention is also suitable for the ultra-fine and ultra-thin powder coating system.
  • the curing agent, pigments, fillers and other additives are pre-mixed, and then thermally processed by an extruder (co-extruded in a molten state) to achieve homogenization.
  • the subsequent powder processing and construction process are no different from ordinary powder coatings, and are practical Strong sex.
  • Fig. 1 is the electrochemical detection result diagram (OCP) of comparative embodiment 1 and embodiment 7 in the present invention
  • Fig. 2 is the electrochemical detection result diagram (R p ) of Comparative Example 1 and Example 7 in the present invention
  • a method for improving the anti-corrosion performance of a powder coating of the present invention comprises adding an anti-corrosion additive to the powder coating;
  • the anti-corrosion additive comprises a first additive, or a second additive, or a third additive, or A mixture of any two of the first adjuvant, the second adjuvant and the third adjuvant, or a mixture of three adjuvants;
  • the first auxiliary agent includes nanoclay; the second auxiliary agent includes a combination of barrier pigment and inorganic salt antirust pigment; composition of metal powders.
  • the method in the present invention is mainly to add an anti-corrosion additive to the powder coating, and the anti-corrosion additive is applied to polyester powder coatings, epoxy powder coatings, sintered epoxy powder coatings, polymer Ester/epoxy hybrid powder coatings, polyurethane powder coatings and acrylic powder coatings, etc., and the application range is not limited to this, it is very extensive.
  • the first auxiliary agent comprises a composition of nanoclay and inorganic salt antirust pigment
  • the barrier pigment is a lamellar structure pigment, including graphene and its derivatives, or mica-like iron oxide, Or mica powder
  • the barrier pigment can also be a non-lamellar auxiliary agent, including barium sulfate, kaolin and the like.
  • the barrier pigments are lamellar structure pigments, and may also include nanoclays.
  • the inorganic salt antirust pigments include zinc phosphate, strontium phosphate, barium phosphate, aluminum phosphate, calcium phosphate, calcium phosphosilicate, strontium phosphosilicate, barium phosphosilicate, calcium borosilicate, and zinc strontium phosphosilicate , one or more metal salts of lithium zinc phosphate.
  • the graphene and its derivatives include graphene, graphene oxide, reduced graphene oxide and surface-treated graphene derivatives;
  • the nanoclay is nanoparticles of silicate minerals, including Exfoliated clay, or bentonite and or organoclay.
  • the carbon nanotubes and derivatives thereof include one or more of single-walled carbon nanotubes, multi-walled carbon nanotubes, oxidized carbon nanotubes, and reduced oxidized carbon nanotubes; the metal powder with sacrificial anode function, It is a metal powder containing one or more of zinc powder, magnesium powder and iron powder.
  • the particle size range of the lamellar structure pigment and the inorganic salt antirust pigment is 5 nanometers to 300 microns; by weight, the dosage range of the lamellar structure pigment and the inorganic salt antirust pigment is 0.1% to 60%.
  • the particle size of the metal powder with sacrificial anode function is in the range of 5 nanometers to 300 microns, and the shape includes spherical and lamellar; by weight, the amount of the metal powder with sacrificial anode function is in the range of 0.1% to 90% , the amount of the carbon nanotubes and their derivatives ranges from 0.1% to 60%.
  • the anti-corrosion additive can enhance the anti-corrosion performance of the coating:
  • the lamellar barrier pigment/filler/auxiliary enhances the protection effect by increasing the tortuosity of the electrolyte in the corrosive environment to penetrate into the metal substrate.
  • patent CN105907265 invented an epoxy resin-based powder coating with modified montmorillonite added, thereby improving the water boiling resistance and cathodic disbonding resistance of the coating.
  • the adjuvant used in this patent does not need to be modified by acidification and intercalation polymerization, which simplifies the preparation method and improves the versatility of montmorillonite.
  • Patent CN106752742 invented an anti-corrosion powder coating with added nano calcium carbonate, which improved the salt spray resistance and heat resistance, but did not indicate the applicable conditions of this method, such as whether it is suitable for mechanical damage, and whether the salt spray test is applicable. Cross the box.
  • Patent CN109971319 uses glass fibers and clay minerals to improve the weather resistance and corrosion resistance of polyester powder coatings, and does not mention the performance of the combination of additives in other powder coating systems such as epoxy. It is speculated from the principle that such coatings are mostly suitable for immersion environments, such as deep burial or immersion in water, and cannot effectively resist the expansion of corrosion after scratching.
  • Active passivation protection additives salt compounds such as zinc phosphate can combine with metal ions generated by the corrosion of metal substrates to form insolubles, which can be used as passivation layers to protect the substrates and prevent further corrosion.
  • adding zinc phosphate to the powder coating formula improves the corrosion resistance and anti-chipping properties of the coating, but it does not mention whether it can protect the coating without the possibility of mechanical damage.
  • CN104893493 uses zinc phosphate, calcium phosphate and other additives and their combinations to develop a high-performance heavy-duty anti-corrosion powder coating.
  • sacrificial anode function such as zinc powder and other metal powders are more active than iron due to their chemical properties, and can form electrochemical primary cells with iron.
  • Zinc acts as an anode self-sacrificing, and iron acts as a cathode to protect iron from corrosion.
  • Patent CN110066569 uses zinc powder with sacrificial anode effect and graphene compound, which reduces the content of zinc powder in the coating, but does not indicate whether the reduced zinc powder still has the protective effect of sacrificial anode.
  • the evaluation is only carried out in epoxy powder coating system, and the performance of this additive combination in other powder coating systems such as polyester and polyurethane is not mentioned.
  • Patent CN101560355 adopts composite iron-titanium powder and flake zinc powder to prepare a heavy-duty anti-corrosion and anti-rust powder coating.
  • the content of flake zinc powder is very low, which may affect its sacrificial anode function.
  • Patent CN103031024 uses glass flakes and zinc powder to improve the performance of marine anti-corrosion powder coatings. Glass flakes with high barrier properties may reduce the conduction between zinc powders and affect their electrochemical activity.
  • This type of zinc-rich coating has high anti-corrosion ability, but excessive zinc powder content (the mass ratio usually needs to be greater than 80%) and other large amounts of solid particle additives will affect the processability and film formation of powder coatings. mechanical properties, such as substrate adhesion, impact resistance, etc.
  • Step 1 Fully mix and stir the anti-corrosion additive and powder coating to form a mixture
  • Step 2 The mixture is processed into a tablet by an extruder or a tablet press;
  • Step 3 Pulverize the flakes with an air classification mill and sieve them to a predetermined particle size.
  • Graphene and zinc phosphate are added to the raw materials of polyester/TGIC powder coating in mass ratios of 0.5% and 1.0%, respectively, and mixed uniformly according to processing step 1, and the prepared mixture is prepared according to processing steps 2 and 3.
  • Graphene and zinc phosphate are added to the raw materials of the polyester/epoxy hybrid powder coating in the mass ratios of 0.5% and 8.0%, respectively, mixed uniformly according to the processing step 1, and the prepared mixture is mixed according to the processing step 2 and 3.
  • the anti-corrosion powder coating with median particle size (D50, V) ⁇ 40 ⁇ m was prepared.
  • the nanoclay and zinc phosphate are added to the raw materials of the polyurethane powder coating in the mass proportions of 6.0% and 2.0% respectively, and the mixture is uniformly mixed according to the processing step 1, and the prepared mixture is prepared according to the processing steps 2 and 3.
  • the nanoclay powder is added to the raw material of the polyester TGIC powder coating in an addition amount of 3% by mass and an addition amount of 2% by mass of zinc phosphate, and mixes uniformly according to the processing step 1, and the prepared mixture is according to the processing step 2.
  • the anti-corrosion powder coating with median particle size (D50, V) ⁇ 40 ⁇ m was prepared with 3.
  • the nanoclay powder is added to the raw material of the polyester TGIC type powder coating in an addition amount of 6% by mass, mixed uniformly according to the processing step 1, and the obtained mixture is prepared according to the processing steps 2 and 3.
  • the carbon nanotubes and the zinc powder are added to the raw materials of the epoxy powder coating in the mass ratios of 2.0% and 80.0% respectively, and the mixture is uniformly mixed according to the processing step 1, and the prepared mixture is prepared according to the processing steps 2 and 3.
  • the carbon nanotubes and zinc powder were added to the raw materials of the polyester/TGIC powder coating in the mass ratios of 2.0% and 40.0%, respectively, mixed uniformly according to the processing step 1, and the prepared mixture was prepared according to the processing steps 2 and 3.
  • Anti-corrosion powder coatings with median particle size (D50, V) ⁇ 40 ⁇ m were obtained.
  • the carbon nanotubes and zinc powder were added to the raw materials of the polyester/HAA powder coating in the mass proportions of 2.0% and 40.0%, respectively, mixed uniformly according to the processing step 1, and the prepared mixture was prepared according to the processing steps 2 and 3.
  • Anti-corrosion powder coatings with median particle size (D50, V) ⁇ 40 ⁇ m were obtained.
  • the carbon nanotubes and the zinc powder are added to the raw materials of the acrylic powder coating in the mass ratios of 2.0% and 40.0% respectively, and the mixture is uniformly mixed according to the processing step 1, and the prepared mixture is prepared according to the processing steps 2 and 3.
  • Nanoclay, zinc phosphate, carbon nanotubes and zinc powder are added to the raw materials of epoxy powder coating in mass ratios of 2.0%, 2.0%, 2% and 40% respectively, and are mixed uniformly according to the processing step 1, and the prepared The mixture is prepared according to the processing steps 2 and 3 to obtain an anti-corrosion powder coating with a median particle size (D50, V) ⁇ 40 ⁇ m.
  • the raw material of the polyester TGIC powder coating was prepared according to the same processing steps to obtain a powder coating with a median particle size (D50, V) of 35 ⁇ m.
  • the raw material of epoxy powder coating and 15% barium sulfate filler were used to prepare powder coating with median particle size (D50, V) of 35 ⁇ m according to the same processing steps.
  • a superfine powder coating with a median particle size (D50, V) of 22 ⁇ m was prepared by using the raw materials of the mixed powder coating and 15% barium sulfate filler according to the same processing steps.
  • Nanoclay was added to other raw materials of polyester/TGIC powder coating in an addition amount of 2.0% to 16.0%, and an ultrafine powder coating with a median particle size (D50, V) of 22 ⁇ m was prepared according to the same processing steps.
  • Graphene was added to other raw materials of polyester/TGIC powder coating in an addition amount of 2.0% to 16.0%, and an ultrafine powder coating with a median particle size (D50, V) of 22 ⁇ m was prepared according to the same processing steps.
  • Zinc phosphate was added to other raw materials of polyester/TGIC powder coating in an addition amount of 2.0% to 16.0%, and an ultrafine powder coating with a median particle size (D50, V) of 22 ⁇ m was prepared according to the same processing steps.
  • the other raw materials of epoxy powder coating are mixed with 15% barium sulfate filler, the resulting mixture is mixed with 80% mass fraction of zinc powder with 20% mass fraction, and the median particle size ( D50,V) 35 ⁇ m powder coating.
  • the following table 2 is the composition table of a plurality of comparative examples:
  • salt spray resistance ASTM B117 and ASTM D1654
  • ASTM B117 and ASTM D1654 are mainly used to test the corrosion resistance of powder coatings.
  • the advantage is that it is easy to operate and interpret the results.
  • electrochemical testing methods especially Electrochemical Impedance Spectroscopy (EIS)
  • EIS Electrochemical Impedance Spectroscopy
  • the experimental development work of the present invention uses electrochemical methods to study in detail the anti-corrosion effects and mechanisms of various combinations of additives.
  • the values that can be obtained by electrochemical measurement include open circuit potential (OCP, Open circuit potential), polarization resistance (Rp, linear The absolute value (
  • OCP Open circuit potential
  • Rp linear
  • OCP Open circuit potential
  • Rp linear
  • electrochemical impedance spectroscopy
  • Rp refers to the DC resistance of the entire system of the coating and the substrate in the OCP ⁇ 10mV region, which is close to the mode (
  • the open circuit potential OCP qualitatively represents the thermodynamic stability of the coating system. For barrier coatings, higher OCP indicates more stable coating properties, ie less prone to corrosion. For sacrificial anode coatings, the lower the OCP, the higher the activation degree of the additive with sacrificial anode function, which is more beneficial to the protection of ferrous substrates.
  • the powder coatings produced in Comparative Examples 1-7 original powder coating formulation and the formulation using a certain auxiliary agent alone
  • the powder coatings produced in Example 1-8 used the same substrate (phosphatized cold-rolled steel plate, 76 ⁇ 152 ⁇ 0.81 mm3), the same spraying, curing conditions and equipment are used for construction and testing, and the exact same dry film thickness of 60 ⁇ 3 ⁇ m is achieved for parallel comparison.
  • the anti-corrosion powder coating salt spray in the control formula examples 1-5 and formula examples 1-8 Test hours are listed in Table 2. Comparing the results, it can be seen that the use of lamellar barrier additives such as nanoclay or graphene alone has limited effect on improving the anti-corrosion performance of powder coatings.
  • the use of zinc phosphate alone can greatly increase the number of hours in the cross-cut salt spray test, that is, repair the damaged area by passivation, and greatly inhibit the expansion process of coating peeling and substrate corrosion in the area near the scratch.
  • the electrochemical test results of the anti-corrosion powder coatings in the control formula examples 1-6 and the formula examples 1-5 are as follows, Table 4 is the electrochemical test results of the partial barrier powder coatings, 0 to 5 days, Measure every 24h:
  • the pencil hardness can be improved by at least one unit, such as from 2B to HB or F, and the wear resistance is also improved accordingly, and the weight loss value of Taber can be reduced after 500 wears. 20%.
  • Comparative Example 7 and Examples 6-10 were constructed and tested with the same substrate, surface treatment method, spraying, curing conditions and equipment, and the same dry film thickness of 60 ⁇ 3 ⁇ m was achieved, for parallel comparison.
  • zinc-rich powder coatings have stronger corrosion resistance than ordinary powder coatings. Unlike powder coating systems using nanoclay alone, zinc powder has the same protective effect on coatings with mechanical damage, one is due to the sacrificial anode effect, and the other is that the corrosion products of zinc powder can partially fill scratches and defects. , preventing further damage to the coating and further corrosion of the substrate.
  • the zinc powder must be interconnected in the coating to transfer electrons to the ferrous substrate.
  • Carbon nanotubes have certain electrical conductivity, and can connect the zinc powder in the coating, so that the zinc powder can fully play its role, especially when the zinc powder is reduced, it can make up for the insufficient connection of the zinc powder.
  • the electrochemical test results of the anti-corrosion powder coatings in Comparative Example 7 and Examples 6-10 are listed in Table 6.
  • the greatly reduced open circuit potential of the zinc-rich powder coating shows that it has a strong sacrificial anode effect, and the higher coating resistance indicates that metal particles such as zinc powder can also improve the barrier properties of the coating.
  • Carbon nanotubes can provide similar sacrificial anode protection with reduced zinc powder content.
  • the additional addition of solid particles also further increases the barrier effect of the coating, delaying the penetration of corrosive media.
  • the cost of zinc powder is high and the hardness is high, and the high amount of zinc powder is not conducive to the life of the twin-screw extruder used for powder coating processing.
  • Example 7 -972 ⁇ -975 105 to 103 10 6 to 10 5
  • Example 6 -951 ⁇ -960 10 7 to 10 3 10 7 to 10 4
  • Example 7 -911 ⁇ -530 105 to 103 105 to 103
  • Example 8 -919 ⁇ -600 10 5 to 10 2 10 5 to 10 2
  • Example 9 -920 ⁇ -880 10 6 to 10 2 10 6 to 10 2
  • Example 10 -895 ⁇ -907 10 7 to 10 3 10 7 to 10 3
  • Comparative Example 1 namely polyester/TGIC varnish, and Example 7, namely the combination of 2% carbon nanotubes and 40% zinc powder; Electrochemical detection result (OCP); as shown in FIG. 2 , it is the electrochemical detection result (R p ) of Comparative Example 1 and Example 7.
  • OCP Electrochemical detection result
  • Comparative Example 1 exhibits only the typical properties of barrier coatings, namely a decrease in OCP and Rp over time, indicating penetration of the electrolyte solution into the coating. Local corrosion of the coating occurred in the later stage of the immersion test in electrochemical impedance spectroscopy.
  • the open circuit potential of Example 7 fluctuates greatly with time, indicating the uneven corrosion of zinc powder from the surface to the substrate in the coating, wherein the conduction of the zinc powder (represented in the open circuit potential value) depends on the electrolysis infiltrated into the coating.
  • the spatial distribution of the liquid The minimum open circuit potential is below -900mV, which is far lower than the critical value of -800mV recommended in the literature, which proves that the coating has a strong anti-corrosion effect on sacrificial anodes.
  • the low open circuit potential value also shows that the carbon nanotubes in the coating play a role in the conduction of the zinc powder.
  • the polarization resistance of the formula sample decreased steadily with time, reflecting the gradual penetration of the electrolyte and the corrosion of the zinc powder.
  • the electrochemical detection results provide an important basis for interpreting the detailed changes of coatings in corrosive media over time.
  • the pencil hardness of Comparative Examples 1 polyyester/TGIC varnish
  • 2 epoxy, containing 15% barium sulfate
  • 3 mixed type, containing 15% barium sulfate
  • impact resistance The values are 25, 20 and 5 kg ⁇ cm, respectively.
  • the pencil hardness of Example 7 was B, and the impact resistance value was 105 kg ⁇ cm.
  • the pencil hardness of Example 6 is HB, and the impact resistance value is 40 kg ⁇ cm.
  • the coating is tested by UV and sunlight accelerated aging (Q-UV and Q-Sun), and the UV resistance and sunlight aging effects of Examples 1, 3, 4, 5, 6, 7, 8 and 9 are all better than those of Example 2 ( polyester/epoxy hybrid) and 10 (epoxy).
  • the resulting gloss retention is the ratio of measured gloss to initial gloss, tested every 7 days. The larger the obtained value, the lower the gloss decline rate and the higher the gloss retention rate, indicating that the anti-UV aging performance of the coating is stronger.
  • Figure 3 it is the UV aging test of Comparative Examples 1 to 10 in the present invention. Result graph.
  • polyester and polyurethane powder coatings The higher gloss retention of polyester and polyurethane powder coatings relative to epoxy powder coatings allows these two anti-corrosion powder coating systems to be used in demanding outdoor sun exposure applications.
  • the powder coatings prepared according to the application examples of the present invention can be used normally on carbon steel, cold-rolled steel and aluminum substrates, and show good appearance, mechanical properties and anti-corrosion properties.
  • the method of the present invention makes it possible for ordinary powder coatings to be used in occasions with high anti-corrosion requirements, and also further improves the performance of heavy-duty anti-corrosion zinc-rich powder coatings.
  • Common powder coatings include polyester powder coatings (polyester/TGIC, polyester/HAA and silicon-modified polyester coatings), polyurethane powder coatings (polyurethane), acrylic powder coatings (acrylic), fluorine-containing powder coatings (such as PVDF, FEVE as Anti-corrosion powder coatings based on base material powder coatings) can be used in outdoor applications under direct sunlight, which greatly expands the application field of powder coatings.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Wood Science & Technology (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Paints Or Removers (AREA)

Abstract

本发明涉及高分子材料的制备方法领域，具体公开了一种提高粉末涂料防腐蚀性能的方法；包括在粉末涂料中添加防腐蚀助剂；所述防腐蚀助剂包含第一助剂，或第二助剂，或第三助剂，或所述第一助剂、第二助剂和第三助剂的任意两种的混合物，或三种助剂的混合物；所述第一助剂包括纳米粘土；所述第二助剂包括阻隔型颜料与无机盐类防锈颜料的组合物；所述第三助剂包括碳纳米管及其衍生物与具有牺牲阳极作用的金属粉末的组合物。本发明采取向普通涂料中添加特殊的复配防腐蚀助剂的方法，所获得的粉末涂料具有更高的防腐蚀性能，还有更广阔的应用领域，包括普通防腐和重防腐，本发明中直接添加助剂的方法比变更树脂固化剂更为经济有效，且通用性更强。

Description

一种提高粉末涂料防腐蚀性能的方法 技术领域
本发明涉及高分子材料的制备领域，尤其涉及一种提高粉末涂料防腐蚀性能的方法。
背景技术
溶剂型涂料是防腐及重防腐涂料行业的主流产品。在传统溶剂型涂料制造、施工及烘烤固化过程中，大量挥发性有机物(VOCs)挥发到空气中。很多广泛使用的溶剂为有毒有害物质，对制造工艺、操作人员及周边环境的安全、健康和环保(HSE)不利。近年来水性涂料在取代溶剂型涂料方面取得了很大进展，但由于干燥慢、施工温度湿度条件苛刻、成本高等因素的制约，仍无法大范围取代溶剂型涂料。
相对于液体涂料，粉末涂料以其独特的无溶剂制造及施工方式获得了广泛应用和快速发展。其优势主要表现在“4个E”，即生态环保(Ecology)、优异的涂层表观(Excellence of finish)、高经济性(Economy)和低能耗(Energy)。
通常使用的粉末涂料化学成分有聚酯(polyester/TGIC及polyester/HAA)、环氧(epoxy)、聚酯/环氧混合型(polyester/epoxy hybrid)、聚氨酯(polyurethane)及丙烯酸(acrylic，即丙烯酸酯)等5种。这5种粉末涂料体系均具有一定的防腐蚀性能，特别是环氧粉末涂料。但环氧树脂主链上的醚键在日光中的紫外光(UV)照射下容易发生断裂，不能用作户外面漆。 聚酯粉末涂料的防腐蚀性能虽略微不及环氧粉末涂料，但不存在日光粉化的问题；因此，上述体系均存在一定缺陷或局限。
发明内容
本发明的目的是提供一种提高粉末涂料防腐蚀性能的方法，通过添加特定防腐蚀助剂，保持现有粉末涂料配方中树脂体系不变的基础，极大提高粉末涂料防腐蚀性能。
为达到上述的技术目的，本发明采用以下技术方案：一种提高粉末涂料防腐蚀性能的方法，包括在粉末涂料中添加防腐蚀助剂；所述防腐蚀助剂包含第一助剂，或第二助剂，或第三助剂，或所述第一助剂、第二助剂和第三助剂的任意两种的混合物，或三种助剂的混合物；所述第一助剂包括纳米粘土；所述第二助剂包括阻隔型颜料与无机盐类防锈颜料的组合物；所述第三助剂包括碳纳米管及其衍生物与具有牺牲阳极作用的金属粉末的组合物。
本发明中，采取向普通涂料中添加特殊的复配防腐蚀助剂的方法，所获得的粉末涂料具有更高的防腐蚀性能，还有更广阔的应用领域，包括普通防腐和重防腐，本发明中直接添加助剂的方法比变更树脂固化剂更为经济有效，且通用性更强。
本发明也可适用于熔结环氧粉末涂料以进一步提升其防腐蚀性能，特别重要的是，本发明经过详细的电化学表征和机理研究，解决了某些情况下单独采用某种或某类助剂不能提升粉末涂料防腐蚀性能的情况，在高外观要求的粉末涂料应用场合，超细粉末涂料能够在不降低涂层表面平整度、光泽、鲜映性(DOI)等指标的情况下，大幅度降低涂膜厚度，从而降低使用成本。
本发明中防腐蚀助剂的配方同样适用于超细超薄粉末涂料体系，在采用添加防腐蚀助剂提高防腐蚀性能的粉末涂料制造过程中，防腐蚀助剂与其它配方组分如树脂、固化剂、颜料、填料及其它助剂预先混合，再经挤出机热加工(熔融状态下共挤出)以达到均质化，后续的粉末化加工及施工工艺与普通粉末涂料无异，实用性强。
附图说明
下面结合附图和具体实施方式对本发明进一步详细的说明。
图1为本发明中对照实施例1及实施例7的电化学检测结果图(OCP)；
图2为本发明中对照实施例1及实施例7的电化学检测结果图(R p)；
图3为本发明中对照实施例1至实施例10的UV老化测试结果图。
具体实施方式
下面对本发明实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例仅仅是本发明的一部分实施例，而不是全部的实施例。基于本发明中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施例，都属于本发明保护的范围。
在下面的描述中阐述了很多具体细节以便于充分理解本发明，但是本发明还可以采用其他不同于在此描述的其它方式来实施，本领域技术人员可以在不违背本发明内涵的情况下做类似推广，因此本发明不受下面公开的具体实施例的限制。
本发明的一种提高粉末涂料防腐蚀性能的方法，包括在粉末涂料中添加防腐蚀助剂；所述防腐蚀助剂包含第一助剂，或第二助剂，或第三助剂，或所述第一助剂、第二助剂和第三助剂的任意两种的混合物，或三种助剂的混合物；
所述第一助剂包括纳米粘土；所述第二助剂包括阻隔型颜料与无机盐类防锈颜料的组合物；所述第三助剂包括碳纳米管及其衍生物与具有牺牲阳极作用的金属粉末的组合物。
因此，本发明中的方法，主要是向粉末涂料中添加防腐蚀助剂，该所述防腐蚀助剂应用于聚酯类粉末涂料、环氧类粉末涂料、熔结环氧类粉末涂料、聚酯/环氧混合型类粉末涂料、聚氨酯类粉末涂料及丙烯酸类粉末涂料等，且应用范围不限于此，非常广泛。
本发明中，所述第一助剂包括纳米粘土与无机盐类防锈颜料的组合物；所述阻隔型颜料为片层状结构颜料，包括石墨烯及其衍生物、或云母状氧化铁、或云母粉；本发明中，所述阻隔型颜料为也可以为非片层状助剂，包括硫酸钡、高岭土等。所述阻隔型颜料为片层状结构颜料，也可包括纳米粘土。
所述无机盐类防锈颜料，包含磷酸锌、磷酸锶、磷酸钡、磷酸铝、磷酸钙、磷硅酸钙、磷硅酸锶、磷硅酸钡、硼硅酸钙、磷硅酸锶锌、磷酸锂锌中的一种或多种的金属盐。
本发明中，所述石墨烯及其衍生物包括石墨烯、氧化石墨烯、还原氧化石墨烯和经表面处理的石墨烯衍生物；所述纳米粘土，为硅酸盐矿物的纳米颗粒，包括蒙脱土、或膨润土和或有机粘土。
所述碳纳米管及其衍生物包括单壁碳纳米管、多壁碳纳米管、氧化碳纳米管、还原氧化碳纳米管中的一种或多种；所述具有牺牲阳极作用的金属粉末，为含有锌粉、镁粉、铁粉中的一种多种的金属粉末。
本发明中，所述片层状结构颜料和无机盐类防锈颜料的粒径范围为5纳米至300微米；按重量比，所述片层状结构颜料和无机盐类防锈颜料的用量范围为0.1％至60％。所述具有牺牲阳极作用的金属粉末的粒径范围为5纳米至300微米，形态包含球状及片层状；按重量比，所述具有牺牲阳极作用的金属粉末的用量范围为0.1％至90％，所述碳纳米管及其衍生物的用量范围为0.1％至60％。
因此，本发明中，防腐蚀助剂能够增强涂料的防腐蚀性能：
1.片层状阻隔颜料/填料/助剂，通过增加腐蚀环境中的电解液渗透到金属基材的曲折性，增强保护效果。如专利CN105907265发明了一种添加改性蒙脱土的环氧树脂基粉末涂料，从而提高了涂层的耐水煮和抗阴极剥离性能。本专利采用的助剂不需要采用酸化及插层聚合改性，简化了制备方法并提高了蒙托土的通用性。专利CN106752742发明了一种添加纳米碳酸钙的防腐粉末涂料，提升了耐盐雾和耐热性能，但并未指出该方法的适用条件，例如是否适用于有无机械损伤的情况，盐雾试验是否划格。另外，配方内还存在硅灰石、凹凸棒土等其它成分，各个成分之间的相互作用在专利中并未提及。专利CN109971319采用玻璃纤维和黏土矿物提升了聚酯型粉末涂料的耐候及防腐蚀性能，未提及助剂组合在其它粉末涂料体系如环氧中的表现。从原理推测，这类涂层多适用于浸入式环境，如深埋或浸入水中，不能有效抵抗划伤后腐蚀的扩张。
2.主动钝化防护助剂，磷酸锌等盐类化合物能与金属底材锈蚀产生的金属离子结合，生成不溶物，该局部不溶物可作为钝化层保护底材，防止腐蚀的进一步发生。如专利CN101864238采用在粉末涂料配方中添加磷酸锌提升涂料的耐腐蚀和抗片落性能，但也未提及是否能够对不存在机械损伤可能性的涂层有防护作用。CN104893493采用磷酸锌、磷酸钙等助剂及其组合，开发了一种高性能重防腐粉末涂料。从原理推测，这类涂层多用于大气腐蚀环境，能够抵御 机械损伤后涂层腐蚀的扩张，但对仅用于浸水或深埋的环境、不存在继续损伤可能性的涂层防腐蚀性能提升有限。
3.具有牺牲阳极作用的助剂，如锌粉等金属粉末由于化学性质比铁活泼，能与铁形成电化学原电池，锌充当阳极自我牺牲，铁充当阴极从而保护铁不受腐蚀。专利CN110066569采用具有牺牲阳极效用的锌粉与石墨烯复配，降低了涂料中的锌粉含量，但并未指出减量后的锌粉是否还具有牺牲阳极的保护作用。而且只在环氧粉末涂料体系中进行了评价，未提及该助剂组合在其它粉末涂料体系如聚酯、聚氨酯中的表现。专利CN101560355采用复合铁钛粉和片状锌粉制得一种重防腐防锈粉末涂料。其中片状锌粉的含量非常低，可能会影响其牺牲阳极功能。专利CN103031024采用玻璃鳞片与锌粉配合，提升了海洋防腐粉末涂料的性能。高阻隔性的玻璃鳞片可能会降低锌粉之间的导通，影响其电化学活性。这类富锌涂层有较高的防腐蚀能力，但过高的锌粉含量(质量比通常需要大于80％)及其它大添加量的固体颗粒助剂会影响粉末涂料的加工性和成膜的机械性能，如基材粘附力，抗冲击性等。
示例型的方案，本发明中，防腐蚀助剂与粉末涂料的具体加工步骤为：
步骤1：将防腐蚀助剂与粉末涂料充分混合搅拌，形成混合物；
步骤2：将混合物采用挤出机或压片机加工成片料；
步骤3：将片料用空气分级磨粉碎并筛分至成预定粒径的成料。
针对防腐蚀助剂中，不同的成分进行多次实验，进行多个实施例如下：
[实施例1]
将石墨烯及磷酸锌分别以质量比例0.5％及1.0％的添加量加至聚酯/TGIC粉末涂料的原材料中，按照加工步骤1混合均匀，所制得的混合物按照加工步骤2与3制得中位数粒径(D50,V)≤40μm的防腐蚀粉末涂料。
[实施例2]
将石墨烯及磷酸锌分别以质量比例0.5％及8.0％的添加量加至聚酯/环氧混合型粉末涂料的原材料中，按照加工步骤1混合均匀，所制得的混合物按照加工步骤2与3制得中位数粒径(D50,V)≤40μm的防腐蚀粉末涂料。
[实施例3]
将纳米粘土及磷酸锌分别以质量比例6.0％及2.0％的添加量加至聚氨酯型粉末涂料的原材料中，按照加工步骤1混合均匀，所制得的混合物按照加工步骤2与3制得中位数粒径(D50,V)≤22μm的防腐蚀超细粉末涂料。
[实施例4]
将纳米粘土粉末以质量比例3％的添加量及磷酸锌质量比例2％的添加量加至聚酯TGIC型粉末涂料的原材料中，按照加工步骤1混合均匀，所制得的混合物按照加工步骤2与3制得中位数粒径(D50,V)≤40μm的防腐蚀粉末涂料。
[实施例5]
将纳米粘土粉末以质量比例6％的添加量加至聚酯TGIC型粉末涂料的原材料中，按照加工步骤1混合均匀，所制得的混合物按照加工步骤2与3制得中位数粒径(D50,V)≤22μm的防腐蚀超细粉末涂料。
[实施例6]
将碳纳米管及锌粉分别以质量比例2.0％与80.0％的添加量加至环氧粉末涂料的原材料中，按照加工步骤1混合均匀，所制得的混合物按照加工步骤2与3制得中位数粒径(D50,V)≤40μm的防腐蚀粉末涂料。
[实施例7]
将碳纳米管及锌粉分别以质量比例2.0％与40.0％的添加量加至聚酯/TGIC粉末涂料的原材料中，按照加工步骤1混合均匀，所制得的混合物按照加工步骤2与3制得中位数粒径(D50,V)≤40μm的防腐蚀粉末涂料。
[实施例8]
将碳纳米管及锌粉分别以质量比例2.0％与40.0％的添加量加至聚酯/HAA粉末涂料的原材料中，按照加工步骤1混合均匀，所制得的混合物按照加工步骤2与3制得中位数粒径(D50,V)≤40μm的防腐蚀粉末涂料。
[实施例9]
将碳纳米管及锌粉分别以质量比例2.0％与40.0％的添加量加至丙烯酸粉末涂料的原材料中，按照加工步骤1混合均匀，所制得的混合物按照加工步骤2与3制得中位数粒径(D50,V)≤40μm的防腐蚀粉末涂料。
[实施例10]
将纳米粘土、磷酸锌、碳纳米管及锌粉分别以2.0％、2.0％、2％及40％的质量比例加至环氧粉末涂料的原材料中，按照加工步骤1混合均匀，所制得的混合物按照加工步骤2与3制得中位数粒径(D50,V)≤40μm的防腐蚀粉末涂料。
如下表1，为根据上述实施例1至实施例10的多个实施例的成分表：
Figure PCTCN2021108523-appb-000001
Figure PCTCN2021108523-appb-000002
表1
为进行实验对比，还进行了多个对照实验实施例，如下：
[对照实施例1]
将聚酯TGIC粉末涂料的原材料，按照同样的加工步骤制得中位数粒径(D50,V)35μm的粉末涂料。
[对照实施例2]
将环氧粉末涂料的原材料与15％硫酸钡填料，按照同样的加工步骤制得中位数粒径(D50,V)35μm的粉末涂料。
[对照实施例3]
将混合型粉末涂料的原材料与15％硫酸钡填料，按照同样的加工步骤制得中位数粒径(D50,V)22μm的超细粉末涂料。
[对照实施例4]
将纳米粘土以2.0％至16.0％的添加量加至聚酯/TGIC粉末涂料的其它原材料，按照同样的加工步骤制得中位数粒径(D50,V)22μm的超细粉末涂料。
[对照实施例5]
将石墨烯以2.0％至16.0％的添加量加至聚酯/TGIC粉末涂料的其它原材料，按照同样的加工步骤制得中位数粒径(D50,V)22μm的超细粉末涂料。
[对照实施例6]
将磷酸锌以2.0％至16.0％的添加量加至聚酯/TGIC粉末涂料的其它原材料，按照同样的加工步骤制得中位数粒径(D50,V)22μm的超细粉末涂料。
[对照实施例7]
将环氧粉末涂料的其它原材料与15％的硫酸钡填料混合，所得的混合物以20％的质量分数再与80％质量分数的锌粉混合，按照同样的加工步骤制得中位数粒径(D50,V)35μm的粉末涂料。
如下表2，为多个对照实施例的成分表：
Figure PCTCN2021108523-appb-000003
表2
针对上述添加了本发明中的防腐蚀助剂，与未添加本发明中的防腐蚀助剂的多个实施例进行对比，评价方法与测试结果：
在粉末涂料行业，主要采用耐盐雾(ASTM B117及ASTM D1654)方法测试粉末涂料的防腐蚀性能。其优点是操作及结果解读简便。在科学研究领域，电化学测试手段、特别是电化学阻抗谱(Electrochemical impedance spectroscopy,EIS)能够提供盐雾试验所不能提供的详细信息，如涂层阻隔性及其随时间的变化。对防护涂层机理的研究有极大的帮助。
本发明的实验开发工作采用电化学方法详细研究了各种助剂组合的防腐蚀效果与机理，电化学测量能够得到的数值有开路电位(OCP,Open circuit potential)、极化电阻(Rp,linear polarization resistance,LPR)及电化学阻抗谱(Electrochemical impedance spectroscopy,EIS)谱线上的低频区阻抗的绝对值(|Z|)。本研究采用0.1Hz频率对应的数值作为屏蔽效应的指标，数值较高表明阻隔效果较好。Rp指的是涂层与底材整个体系的在OCP±10mV 区域的直流电阻，与EIS低频区阻抗的模(|Z|)含义接近，越高表明涂层越致密，缺陷越少。开路电位OCP定性表示的是涂层体系的热力学稳定性。对阻隔型涂料而言，OCP越高表明涂层性质越稳定，即越不容易发生腐蚀。对牺牲阳极型涂料而言，OCP越低表明具有牺牲阳极功能的助剂活化程度越高，越有利于保护铁质底材。
1、阻隔型普通粉末涂料与阻隔型超细粉末涂料
将对照实施例1-7(原始粉末涂料配方及单独使用某助剂的配方)与实施例1-8生产的粉末涂料采用相同底材(经磷化处理的冷轧钢板，76×152×0.81mm3)、相同喷涂、固化条件及仪器设备进行施工及测试，并达到完全相同的干膜厚度60±3μm，以便平行对比。
经盐雾测试(ASTM B117及D1654，初始划格宽度0.5mm，平均腐蚀宽度达到2mm所需小时数)，对照配方实施例1-5及配方实施例1-8中的防腐蚀粉末涂料盐雾测试小时数列于表2。比较各结果可知，单独使用纳米粘土或石墨烯等片层阻隔型助剂提升粉末涂料的防腐蚀性能作用有限。单独使用磷酸锌能大幅度提高划格盐雾试验的小时数，即通过钝化修复破损区域，大幅度抑制划痕附近区域涂层剥离与底材腐蚀的扩张进程。
如下表3，为部分阻隔型粉末涂料的盐雾测试结果：
Figure PCTCN2021108523-appb-000004
Figure PCTCN2021108523-appb-000005
表3
经电化学测试，对照配方实施例1-6及配方实施例1-5中的防腐蚀粉末涂料电化学测试结果如下，表4为部分阻隔型粉末涂料的电化学测试结果，0～5天，每24h测量一次：
Figure PCTCN2021108523-appb-000006
表4
比较对照实施例4～6的结果可知，含纳米粘土的最优配方相对于对照实施例1～3，其涂层的片层阻隔性能有极大的提升，即Rp与|Z|，f＝0.1Hz的数 值提高了3个数量级。而含有不同添加量的磷酸锌对阻隔性能的提升并不明显，原因是其粒径较小，对涂层中曲折通路的增加贡献较少。
以上盐雾测试与电化学的结果完全不相符，原因是盐雾测试只能反映在受到机械损伤的情况下涂层剥离与底材腐蚀的扩展情况，而电化学手段表征的是绝大部分涂层面积完好的情况下电解质溶液在涂层中向底材逐步渗透的详细过程。两者不可混淆。另外，在单独使用纳米粘土的情况下，过高的添加量(自4％起)会导致划格处更严重的涂层剥离与腐蚀，原因是纳米粘土遇水膨胀。
通过添加磷酸锌等有钝化性能的助剂，石墨烯和纳米粘土只能在未受机械损伤的情况下发挥作用的缺点得到了有效的弥补，体现在更高的盐雾试验小时数和各个电化学测试指标及盐雾测试结果。另外经测试，涂料的其它性能如镜面光泽(ASTM D523)、铅笔硬度(ASTM D3363)、鲜映性(DOI，ASTM D5767)、抗冲击(ASTM D2794)、Taber耐磨(ASTM D4060)等均能满足工业应用要求，特别是添加各种助剂后铅笔硬度能够提高至少一个单位，例如从2B提到至HB或F，耐磨性能也有相应提升，Taber耐磨500次后减重的数值能够减少20％。2、牺牲阳极型重防腐粉末涂料
将对照实施例7和实施例6-10生产的粉末涂料与采用同样的底材、表面处理方式、喷涂、固化条件及仪器设备进行施工及测试，并达到完全相同的干膜厚度60±3μm，以便平行对比。
经盐雾测试(ASTM B117及D1654)，富锌粉末涂料比普通粉末涂料具有更强的防腐蚀性能。与单独使用纳米粘土的粉末涂料体系不同的是，锌粉对带有机械损伤的涂层有同样的保护作用，一是由于牺牲阳极效应，二是锌粉的腐蚀产物能够部分填充划痕与缺陷，阻止涂层的进一步破坏和底材的进一步腐蚀。在涂层中锌粉必须互相连通才能将电子传到给铁质底材。碳纳米管具有一定的 导电性能，能够连通涂层中的锌粉，使锌粉充分发挥作用，特别是在锌粉减量的情况下能够弥补锌粉连通不够的缺陷。
如下表5所示，为部分牺牲阳极型粉末涂料的盐雾测试结果：
Figure PCTCN2021108523-appb-000007
表5
对照实施例7和实施例6-10中防腐蚀粉末涂料的电化学测试结果列于表6。富锌粉末涂料大幅降低的开路电位显示其具有很强的牺牲阳极效应，而且更高的涂层阻抗说明锌粉等金属颗粒也能提高涂层的阻隔性能。碳纳米管能够在锌粉含量降低的情况下提供相近的牺牲阳极保护功能。额外添加的固体颗粒也进一步增加了涂层的屏蔽效应，延缓了腐蚀介质的渗入。锌粉的成本较高且硬度很高，高添加量的锌粉对粉末涂料加工用的双螺杆挤出机的寿命不利。
如下表表6，为部分牺牲阳极型粉末涂料的电化学测试结果，0～20天，每24h测量一次：
编号 开路电位，mV 极化电阻R p，Ω·cm 2 |Z|，f＝0.1Hz，Ω·cm 2
对照实施例7 -972～-975 10 5～10 3 10 6～10 5
实施例6 -951～-960 10 7～10 3 10 7～10 4
实施例7 -911～-530 10 5～10 3 10 5～10 3
实施例8 -919～-600 10 5～10 2 10 5～10 2
实施例9 -920～-880 10 6～10 2 10 6～10 2
实施例10 -895～-907 10 7～10 3 10 7～10 3
表6
本发明中，对照实施例1，即聚酯/TGIC清漆，实施例7，即碳纳米管2％及锌粉40％的组合；如图1所示，为对照实施例1及实施例7的电化学检测结果(OCP)；如图2所示，为对照实施例1及实施例7的电化学检测结果(R p)。
对照实施例1仅表现出阻隔型涂层的典型性质，即OCP及Rp随时间下降，表示电解质溶液渗入涂层。电化学阻抗谱中浸泡试验后期涂层局部发生锈蚀。
实施例7的开路电位随时间大幅波动，表示锌粉在涂层中由表面向底材的不均匀腐蚀，其中锌粉的导通情况(体现于开路电位数值)取决于渗入涂层内的电解液的空间分布。最低开路电位为-900mV以下，远低于文献推荐的临界值-800mV，证明该涂层有很强的牺牲阳极防腐蚀作用。很低开路电位数值同时也说明涂层中的碳纳米管对锌粉的导通起到了作用。该配方样板的极化电阻随时间稳步下降，体现了电解液的逐步渗入与锌粉的腐蚀。电化学检测结果为解释涂层在腐蚀介质中的随时间的详细变化情况提供了重要依据。
3、机械性能、耐UV及日光老化效果
经测试，添加锌粉能够增强粉末涂料的铅笔硬度(ASTMD3363)及抗冲击性能(ASTMD2794)。例如对照实施例1(聚酯/TGIC清漆)、2(环氧，含15％硫酸钡)、3(混合型，含15％硫酸钡)的铅笔硬度均为2B(60μm膜厚)，抗冲击数值分别为25、20和5kg·cm。添加40％锌粉后实施例7的铅笔硬度为B，抗冲击数值为105kg·cm。添加80％锌粉后实施例6的铅笔硬度为HB，抗冲击数值为40kg·cm。
涂层经UV及日光加速老化测试(Q-UV及Q-Sun)，实施例1、3、4、5、6、7、8及9的耐UV及日光老化效果均好于实施例2(聚酯/环氧混合型)及10(环氧)。作为结果的保光率为测得光泽与初始光泽的比率，每7天测试一次。所 得数值越大即光泽下降率越低、保光率越高，表示涂层的抗UV老化性能越强，如图3所示，为本发明中对照实施例1至实施例10的UV老化测试结果图。
相对于环氧粉末涂料，聚酯及聚氨酯粉末涂料更高的保光率使得这两种防腐蚀粉末涂料体系得以用于高要求的户外日光暴露场合。
除磷化钢板外，按照本发明的应用实施例制得的粉末涂料在碳钢、冷轧钢及铝质底材上均能够正常使用，并表现出良好的外观、机械性能及防腐蚀性能。
因此，可以看出，本发明的方法，使普通粉末涂料用于高防腐蚀要求的场合成为可能，同时也进一步提升了重防腐富锌粉末涂料的性能。普通粉末涂料中以聚酯粉末涂料(polyester/TGIC、polyester/HAA及硅改性聚酯涂料)、聚氨酯粉末涂料(polyurethane)、丙烯酸粉末涂料(acrylic)、含氟粉末涂料(例如PVDF、FEVE为基料的粉末涂料)等为基础的防腐蚀粉末涂料可用于阳光直射的户外应用场合，极大地拓展了粉末涂料的应用领域。
以上所述仅为本发明的优选实施例而已，并不用于限制本发明，尽管参照前述实施例对本发明进行了详细的说明，对于本领域的技术人员来说，其依然可以对前述各实施例所记载的技术方案进行修改，或者对其中部分技术特征进行等同替换，凡在本发明的精神和原则之内，所作的任何修改、等同替换、改进等，均应包含在本发明的保护范围之内。

Claims (10)

  1. 一种提高粉末涂料防腐蚀性能的方法，其特征在于，所述方法包括在粉末涂料中添加防腐蚀助剂；所述防腐蚀助剂包含第一助剂，或第二助剂，或第三助剂，或所述第一助剂、第二助剂和第三助剂的任意两种的混合物，或三种助剂的混合物；
    所述第一助剂包括纳米粘土；
    所述第二助剂包括阻隔型颜料与无机盐类防锈颜料的组合物；
    所述第三助剂包括碳纳米管及其衍生物与具有牺牲阳极作用的金属粉末的组合物。
  2. 根据权利要求1所述的方法，其特征在于：所述防腐蚀助剂应用于聚酯类粉末涂料、环氧类粉末涂料、熔结环氧类粉末涂料、聚酯/环氧混合型类粉末涂料、聚氨酯类粉末涂料、丙烯酸类粉末涂料及含氟粉末涂料。
  3. 根据权利要求1所述的方法，其特征在于：所述第一助剂包括纳米粘土与无机盐类防锈颜料的组合物；
    所述阻隔型颜料为片层状结构颜料，包括石墨烯及其衍生物、或云母状氧化铁、或云母粉；
    所述无机盐类防锈颜料，包含磷酸锌、磷酸锶、磷酸钡、磷酸铝、磷酸钙、磷硅酸钙、磷硅酸锶、磷硅酸钡、硼硅酸钙、磷硅酸锶锌、磷酸锂锌中的一种或多种的金属盐。
  4. 根据权利要求3所述的方法，其特征在于：所述石墨烯及其衍生物包括石墨烯、氧化石墨烯、还原氧化石墨烯和经表面处理的石墨烯衍生物；
    所述纳米粘土，为硅酸盐矿物的纳米颗粒，包括蒙脱土、或膨润土或有机粘土。
  5. 根据权利要求1所述的方法，其特征在于：所述碳纳米管及其衍生物包括单壁碳纳米管、多壁碳纳米管、氧化碳纳米管、还原氧化碳纳米管中的一种或多种；
    所述具有牺牲阳极作用的金属粉末，为含有锌粉、镁粉、铁粉中的一种多种的金属粉末。
  6. 根据权利要求3所述的方法，其特征在于：所述片层状结构颜料和无机盐类防锈颜料的粒径范围为5纳米至300微米；
  7. 根据权利要求3所述的方法，其特征在于：按重量比，所述片层状结构颜料和无机盐类防锈颜料的用量范围为0.1％至60％。
  8. 根据权利要求1所述的方法，其特征在于，所述具有牺牲阳极作用的金属粉末的粒径范围为5纳米至300微米，形态包含球状及片层状。
  9. 根据权利要求1所述的方法，其特征在于，按重量比，所述具有牺牲阳极作用的金属粉末的用量范围为0.1％至90％，所述碳纳米管及其衍生物的用量范围为0.1％至60％。
  10. 根据权利要求1所述的方法，其特征在于，所述方法包括：
    将防腐蚀助剂与粉末涂料充分混合搅拌，形成混合物；
    将混合物采用挤出机或压片机加工成片料；
    将片料用空气分级磨粉碎并筛分至成预定粒径的成料。
PCT/CN2021/108523 2020-12-19 2021-07-27 一种提高粉末涂料防腐蚀性能的方法 WO2022127115A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202011515222.9 2020-12-19
CN202011515222.9A CN112694775A (zh) 2020-12-19 2020-12-19 一种提高粉末涂料防腐蚀性能的方法

Publications (1)

Publication Number Publication Date
WO2022127115A1 true WO2022127115A1 (zh) 2022-06-23

Family

ID=75507611

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2021/108523 WO2022127115A1 (zh) 2020-12-19 2021-07-27 一种提高粉末涂料防腐蚀性能的方法

Country Status (2)

Country Link
CN (1) CN112694775A (zh)
WO (1) WO2022127115A1 (zh)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116144247A (zh) * 2023-02-23 2023-05-23 广州特种承压设备检测研究院 一种石墨烯／纳米铁复合改性环氧树脂防腐涂层材料及其制备方法
CN116535932A (zh) * 2023-05-09 2023-08-04 国网江西省电力有限公司电力科学研究院 一种石墨烯导电防腐蚀涂料及其制备方法

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112694775A (zh) * 2020-12-19 2021-04-23 天津西敦粉漆科技有限公司 一种提高粉末涂料防腐蚀性能的方法
CN113563785A (zh) * 2021-07-12 2021-10-29 安徽桑瑞斯环保新材料有限公司 基于石墨烯环氧的防腐底粉及其制备方法
CN116355489A (zh) * 2021-12-28 2023-06-30 广东华润涂料有限公司 无铬防腐涂料组合物以及由其制成的制品
CN116355490A (zh) * 2021-12-28 2023-06-30 广东华润涂料有限公司 无铬防腐涂料组合物以及由其制成的制品
CN115948105A (zh) * 2022-12-28 2023-04-11 广东西敦千江粉漆科学研究有限公司 一种抗涂鸦粉末涂料组合物及其制备方法

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101033364A (zh) * 2006-03-07 2007-09-12 徐州正菱涂装有限公司 锌基重防腐粉末涂料及其制备方法
CN101864238A (zh) * 2009-04-03 2010-10-20 罗门哈斯公司 耐腐蚀和抗片落的粉末涂层
CN107603417A (zh) * 2017-10-30 2018-01-19 天津美士邦涂料化工有限公司 一种碳纳米管石墨烯富锌含氧防腐涂料的制备方法
CN108864905A (zh) * 2018-05-31 2018-11-23 华南理工大学 一种含片层状磷酸锆和碳纳米管的海洋防腐粉末涂料及其制备方法与应用
CN112694775A (zh) * 2020-12-19 2021-04-23 天津西敦粉漆科技有限公司 一种提高粉末涂料防腐蚀性能的方法

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA2226633A1 (en) * 1995-07-14 1997-02-06 Armco Inc. Metal substrate with enhanced corrosion resistance and improved paint adhesion
CN104893493B (zh) * 2015-05-11 2017-03-01 国润恒科（天津）防腐工程技术有限公司 一种高性能重防腐粉末涂料及制备方法和应用
CN108178964A (zh) * 2017-11-01 2018-06-19 百氏高涂料（苏州）有限公司 一种石墨烯无溶剂防腐涂料及制备技术
US11183314B2 (en) * 2018-05-14 2021-11-23 University Of Florida Research Foundation, Inc. Methods and compositions for minimizing x-ray scattering artifacts
CN109181400B (zh) * 2018-07-20 2021-09-17 天津西敦粉漆科技有限公司 一种粉末涂料与颜料的微波加热绑定方法

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101033364A (zh) * 2006-03-07 2007-09-12 徐州正菱涂装有限公司 锌基重防腐粉末涂料及其制备方法
CN101864238A (zh) * 2009-04-03 2010-10-20 罗门哈斯公司 耐腐蚀和抗片落的粉末涂层
CN107603417A (zh) * 2017-10-30 2018-01-19 天津美士邦涂料化工有限公司 一种碳纳米管石墨烯富锌含氧防腐涂料的制备方法
CN108864905A (zh) * 2018-05-31 2018-11-23 华南理工大学 一种含片层状磷酸锆和碳纳米管的海洋防腐粉末涂料及其制备方法与应用
CN112694775A (zh) * 2020-12-19 2021-04-23 天津西敦粉漆科技有限公司 一种提高粉末涂料防腐蚀性能的方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
ZHANG HUI, ET AL.: "Research Status and Development of Functional Powder Coatings", HUAXUE GONGYE YU GONGCHENG - CHEMICAL INDUSTRY AND ENGINEERING, XX, TIANJIN, CN, vol. 37, no. 2, 31 March 2020 (2020-03-31), CN , pages 1 - 18, XP055943584, ISSN: 1004-9533, DOI: 10.13353/j.issn.1004.9533.20191911 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116144247A (zh) * 2023-02-23 2023-05-23 广州特种承压设备检测研究院 一种石墨烯／纳米铁复合改性环氧树脂防腐涂层材料及其制备方法
CN116535932A (zh) * 2023-05-09 2023-08-04 国网江西省电力有限公司电力科学研究院 一种石墨烯导电防腐蚀涂料及其制备方法

Also Published As

Publication number Publication date
CN112694775A (zh) 2021-04-23

Similar Documents

Publication Publication Date Title
WO2022127115A1 (zh) 一种提高粉末涂料防腐蚀性能的方法
Cui et al. Poly (o-phenylenediamine) modified graphene toward the reinforcement in corrosion protection of epoxy coatings
Wu et al. Non-covalently functionalized boron nitride by graphene oxide for anticorrosive reinforcement of water-borne epoxy coating
Yan et al. Ti3C2 MXene nanosheets toward high-performance corrosion inhibitor for epoxy coating
Zhong et al. Self-assembled graphene oxide-graphene hybrids for enhancing the corrosion resistance of waterborne epoxy coating
Di et al. Corrosion-resistant hybrid coatings based on graphene oxide–zirconia dioxide/epoxy system
Lin et al. A robust and eco-friendly waterborne anti-corrosion composite coating with multiple synergistic corrosion protections
Ramezanzadeh et al. Synthesis and characterization of polyaniline tailored graphene oxide quantum dot as an advance and highly crystalline carbon-based luminescent nanomaterial for fabrication of an effective anti-corrosion epoxy system on mild steel
Li et al. Highly effective anti-corrosion epoxy spray coatings containing self-assembled clay in smectic order
Zhang et al. Fabrication of oriented layered double hydroxide films by spin coating and their use in corrosion protection
Ge et al. Design alternate epoxy-reduced graphene oxide/epoxy-zinc multilayer coatings for achieving long-term corrosion resistance for Cu
Zhao et al. The efficient exfoliation and dispersion of hBN nanoplatelets: advanced application to waterborne anticorrosion coatings
CN107459906A (zh) 抗腐蚀复合层
Xu et al. A novel polymer composite coating with high thermal conductivity and unique anti-corrosion performance
Wu et al. A study on corrosion behavior of micro-arc oxidation coatings doped with 2-aminobenzimidazole loaded halloysite nanotubes on AZ31 magnesium alloys
Wu et al. Deposition of Zn-G/Al composite coating with excellent cathodic protection on low-carbon steel by low-pressure cold spraying
CN105602415B (zh) 钢结构表面防护用vci粉末富锌涂料及其制备方法
EP2917291B1 (en) Anticorrosive pigments incorporated in topcoats
WO2021068506A1 (zh) 一种基于氧化石墨烯的水基防腐涂料及其制备方法
CN107400441A (zh) 石墨烯改性水性环氧重防腐涂料制备工艺
Mohammadi et al. Electrochemical and anticorrosion behaviors of hybrid functionalized graphite nano-platelets/tripolyphosphate in epoxy-coated carbon steel
CN105542621B (zh) 钢结构表面防护用vci粉末双金属涂料及其制备方法
CN1775880A (zh) 高耐盐水性红丹醇酸防锈漆及其制造方法
Zhu et al. Corrosion resistance of polyvinyl butyral/reduced graphene oxide/titanium dioxide composite coatings for stainless steel in different environments
CN112961571A (zh) 一种包含氧化石墨烯/黑滑石复合材料的环氧富锌防腐涂料及其制备方法

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 21905048

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 21905048

Country of ref document: EP

Kind code of ref document: A1