CN111303751B - Self-repairing powder coating based on polyurethane resin and preparation method thereof - Google Patents

Self-repairing powder coating based on polyurethane resin and preparation method thereof Download PDF

Info

Publication number
CN111303751B
CN111303751B CN202010163189.1A CN202010163189A CN111303751B CN 111303751 B CN111303751 B CN 111303751B CN 202010163189 A CN202010163189 A CN 202010163189A CN 111303751 B CN111303751 B CN 111303751B
Authority
CN
China
Prior art keywords
parts
powder coating
repairing
polyurethane resin
self
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
Application number
CN202010163189.1A
Other languages
Chinese (zh)
Other versions
CN111303751A (en
Inventor
费邦忠
周正华
查全达
费安道
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Anhui Huahui Suye Technology Share Co ltd
Original Assignee
Anhui Huahui Suye Technology Share Co ltd
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 Anhui Huahui Suye Technology Share Co ltd filed Critical Anhui Huahui Suye Technology Share Co ltd
Priority to CN202010163189.1A priority Critical patent/CN111303751B/en
Publication of CN111303751A publication Critical patent/CN111303751A/en
Application granted granted Critical
Publication of CN111303751B publication Critical patent/CN111303751B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

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
    • C09D175/00—Coating compositions based on polyureas or polyurethanes; Coating compositions based on derivatives of such polymers
    • C09D175/04—Polyurethanes
    • C09D175/08—Polyurethanes from polyethers
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/30—Low-molecular-weight compounds
    • C08G18/32—Polyhydroxy compounds; Polyamines; Hydroxyamines
    • C08G18/3225—Polyamines
    • C08G18/3237—Polyamines aromatic
    • C08G18/3243—Polyamines aromatic containing two or more aromatic rings
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/40—High-molecular-weight compounds
    • C08G18/4009—Two or more macromolecular compounds not provided for in one single group of groups C08G18/42 - C08G18/64
    • C08G18/4018—Mixtures of compounds of group C08G18/42 with compounds of group C08G18/48
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/40—High-molecular-weight compounds
    • C08G18/42—Polycondensates having carboxylic or carbonic ester groups in the main chain
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/40—High-molecular-weight compounds
    • C08G18/48—Polyethers
    • C08G18/4854—Polyethers containing oxyalkylene groups having four carbon atoms in the alkylene group
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/65—Low-molecular-weight compounds having active hydrogen with high-molecular-weight compounds having active hydrogen
    • C08G18/66—Compounds of groups C08G18/42, C08G18/48, or C08G18/52
    • C08G18/6603—Compounds of groups C08G18/42, C08G18/48, or C08G18/52 with compounds of group C08G18/32 or polyamines of C08G18/38
    • C08G18/6614—Compounds of groups C08G18/42, C08G18/48, or C08G18/52 with compounds of group C08G18/32 or polyamines of C08G18/38 with compounds of group C08G18/3225 or C08G18/3271 and/or polyamines of C08G18/38
    • C08G18/6618—Compounds of groups C08G18/42, C08G18/48, or C08G18/52 with compounds of group C08G18/32 or polyamines of C08G18/38 with compounds of group C08G18/3225 or C08G18/3271 and/or polyamines of C08G18/38 with compounds of group C08G18/3225 or polyamines of C08G18/38
    • 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
    • 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
    • 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
    • C09D5/16—Antifouling paints; Underwater paints
    • C09D5/1656—Antifouling paints; Underwater paints characterised by the film-forming substance
    • C09D5/1662—Synthetic film-forming substance
    • 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
    • C09D5/16—Antifouling paints; Underwater paints
    • C09D5/1687—Use of special additives
    • 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
    • C09D5/18—Fireproof paints including high temperature resistant paints
    • 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
    • C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
    • C08K3/20—Oxides; Hydroxides
    • C08K3/22—Oxides; Hydroxides of metals
    • C08K2003/2227—Oxides; Hydroxides of metals of aluminium
    • 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
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L2201/00—Properties
    • C08L2201/08—Stabilised against heat, light or radiation or oxydation

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Wood Science & Technology (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Paints Or Removers (AREA)
  • Polyurethanes Or Polyureas (AREA)

Abstract

The invention discloses a self-repairing powder coating based on polyurethane resin, which is prepared from the following raw materials in parts by weight: 50-60 parts of modified polyurethane resin, 6-8 parts of silicon modified hydroxyl acrylic resin, 10-14 parts of curing agent, 1-1.4 parts of flatting agent, 0.5-0.6 part of brightener, 0.2-0.3 part of curing accelerator and 20-26 parts of composite filler; the invention also discloses a preparation method of the powder coating. The modified polyurethane resin is used as a film forming material, so that the heat-resistant performance is high, repeated self-repairing can be realized at room temperature for many times, and the self-repairing effect cannot be reduced along with the increase of repairing times; by doping the composite filler into the powder coating, the composite filler can be uniformly dispersed in a polyurethane matrix, has strong interaction with the matrix, and improves the heat resistance, corrosion resistance and mechanical property of the coating; the auxiliary preparation of the silicon modified hydroxyl acrylic resin can also provide the easy-to-clean and anti-doodling performance of the coating.

Description

Self-repairing powder coating based on polyurethane resin and preparation method thereof
Technical Field
The invention belongs to the field of powder coatings, and particularly relates to a self-repairing powder coating based on polyurethane resin and a preparation method thereof.
Background
With the development of economy, especially the development of automobile industry, ship industry, building industry and home decoration industry, functional coatings such as self-cleaning coatings, anti-reflection coatings, anti-corrosion coatings, antibacterial coatings and the like have become hot spots for scientific research of domestic and foreign materials. The self-repairing powder coating can perform a self-repairing function on a coating crack generated by an external force, so that the service life of the coating is effectively prolonged, and the self-repairing powder coating is concerned.
The powder coating for the vehicle body coating disclosed in the Chinese patent application CN201510349629.1 comprises the following raw materials in parts by weight: the paint comprises, by mass, 60-66.5% of carboxyl saturated polyester resin, 40-33.5% of toughening epoxy resin, 0.5-1% of a leveling agent, 0.3-0.6% of a degassing agent, 0-32.5% of a pigment and 65-85% of a filler, wherein the mass ratio of the carboxyl saturated polyester resin to the toughening epoxy resin is 60-66.5:40-33.5, and the sum of the mass of the carboxyl saturated polyester resin and the toughening epoxy resin accounts for 65-85% of the total weight of the raw materials. The coating prepared from the powder coating has excellent adhesion to an electrophoretic primer and a top coat, and has a very strong self-repairing function; but the crosslinking degree of the epoxy resin in a cured coating is low, self-repair is realized through chemical action, and the repair effect is greatly reduced along with the increase of the repair times.
Disclosure of Invention
The invention aims to provide a self-repairing powder coating based on polyurethane resin and a preparation method thereof, wherein the modified polyurethane resin is used as a film forming substance, so that the powder coating has high heat resistance, can realize repeated self-repairing at room temperature, and has a self-repairing effect which is not reduced along with the increase of repairing times, so that the powder coating has an excellent self-repairing effect; by doping the composite filler into the powder coating, the composite filler can be uniformly dispersed in a polyurethane matrix through a series of treatments, and has stronger interaction with the matrix, so that the heat resistance, corrosion resistance and mechanical property of the coating are improved; the auxiliary preparation of the silicon modified hydroxyl acrylic resin can provide easy-to-clean and anti-doodling performance of the coating; the powder coating obtained by the invention has excellent self-repairing performance and excellent comprehensive performance, and is suitable for the automobile industry, the ship industry, the building industry and the family decoration industry.
The purpose of the invention can be realized by the following technical scheme:
a self-repairing powder coating based on polyurethane resin is prepared from the following raw materials in parts by weight: 50-60 parts of modified polyurethane resin, 6-8 parts of silicon modified hydroxyl acrylic resin, 10-14 parts of curing agent, 1-1.4 parts of flatting agent, 0.5-0.6 part of brightener, 0.2-0.3 part of curing accelerator and 20-26 parts of composite filler;
the powder coating is prepared by the following steps:
firstly, weighing the raw materials according to the parts by weight, adding the raw materials into a stirring cylinder, and stirring for 4-6min under the condition of the rotating speed of 400 r/min;
secondly, pouring the mixture into a double-screw extruder, and performing melt extrusion, wherein the heating conditions of the extruder are that the temperature of a zone I is 110 ℃ and the temperature of a zone II is 125 ℃;
and step three, after the extrusion is finished, cooling to normal temperature, sending into a flour mill for milling, wherein the milling conditions are that the main milling rotation speed is 8500-.
Further, the acid value of the silicon modified hydroxy acrylic resin is 40-50 mgKOH/g.
Further, the modified polyurethane resin is prepared by the following method:
adding isophorone diisocyanate and polytetrahydrofuran diol in a molar ratio of 2:1 into a flask provided with a stirrer, a thermometer and a condenser, dropwise adding a proper amount of stannous octoate catalyst, heating to 80-90 ℃ under the protection of nitrogen, reacting for 2-3h, adding dendritic polyester polyol, reacting for 2-3h, cooling to 50-60 ℃, adding a proper amount of 2,2' -diaminoethylene glycol diphenyl ether, reacting for 1-2h, adding a proper amount of N-methylpyrrolidone in the whole process to reduce the viscosity of the reaction system, and finally performing vacuum desolventization to obtain the modified polyurethane resin.
Further, the composite filler is prepared by the following method:
(1) weighing 5g of ZrOCl2·8H2O and 0.2g hexamethylenediamine in 60mL of H3PO4Stirring the solution uniformly, transferring the solution into a stainless steel reaction kettle with a polytetrafluoroethylene lining, heating the solution at 200 ℃ for reaction for 24 hours, after the reaction is finished, performing vacuum filtration, repeatedly washing the product for 8 to 10 times by using deionized water, and drying the product in a vacuum drying oven at 80 DEG CGrinding for 24 hours to obtain zirconium phosphate nanosheet powder;
(2) weighing 2.6g of nano Al2O3And 3.2g of zirconium phosphate nanosheet powder are added into a three-necked bottle filled with 155mL of ethanol water solution, ultrasonic dispersion is carried out for 30min, then 1.6g of hexadecyl trimethyl ammonium bromide is dropwise added under the stirring condition, the ultrasonic dispersion is continued, the mixed solution is heated, stirred and refluxed for 6h at 80 ℃, cooled, repeatedly washed and centrifuged, dried at 80 ℃, and ground to obtain the composite filler.
Further, step (1) is H3PO4The concentration of the solution is 3mol/L, and the mass fraction of the ethanol water solution in the step (2) is 98 percent.
A preparation method of a self-repairing powder coating based on polyurethane resin comprises the following steps:
firstly, weighing raw materials according to parts by weight, adding the raw materials into a stirring cylinder, and stirring for 4-6min under the condition of a rotating speed of 400 r/min;
secondly, pouring the mixture into a double-screw extruder, and performing melt extrusion, wherein the heating conditions of the extruder are that the temperature of a zone I is 110 ℃ and the temperature of a zone II is 125 ℃;
and step three, after the extrusion is finished, cooling to normal temperature, sending the mixture into a flour mill for milling, wherein the milling conditions are that the main milling rotating speed is 8500-9500r/min, the auxiliary milling rotating speed is 6500-7500r/min, and sieving the mixture through a 180-mesh sieve to obtain the powder coating.
The invention has the beneficial effects that:
the powder coating adopts modified polyurethane as a polymer matrix, dendritic polyester polyol as an inner core, polyurethane prepolymer is formed by in-situ polymerization as an inner layer, and 2,2' -diaminoglycol diphenyl ether is introduced and passes through-NH2The modified polyurethane is prepared by the reaction of the modified polyurethane with-NCO group, the reaction is connected into a dendritic polyurethane molecular chain, and then the modified polyurethane is formed by in-situ crosslinking; the formed modified polyurethane has a network skeleton mechanism, so that hydrogen bonds in the polyurethane are mutually crossed to form a stable hydrogen bond network structure, and the thermal stability of the polyurethane is obviously improved; the obtained modified polyurethane has a self-repairing function, a hydrogen bond is formed between N-H and C ═ O to complete a self-repairing process, and when a coating is damaged, molecular chains flow through each other to quickly form a new polyurethaneThe method has the advantages that the repair is realized through hydrogen bonds, the repeated repair can be realized for many times, the repair performance and efficiency are reduced unobviously along with the increase of the repair times, the repair efficiency and the reduction of the material performance are obvious along with the increase of the repair times through introducing chemical bonds in the common polyurethane repair, the hydrogen bonds have repeatability at room temperature, and meanwhile, the dendritic polyester polyol introduced during the synthesis improves the hydrogen bond density;
according to the invention, composite filler is added into the powder coating, firstly, lamellar zirconium phosphate nanosheets are synthesized by a hydrothermal method, and hexamethylenediamine and-NH on the surface of the hexamethylenediamine are added in the hydrothermal synthesis process2Reacting with hydroxyl on the surface of zirconium phosphate, and grafting on a zirconium phosphate sheet layer; the zirconium phosphate nanosheets and the powder of the nano aluminum oxide are treated by the cetyl trimethyl ammonium bromide, on one hand, the cetyl trimethyl ammonium bromide and the zirconium phosphate nanosheets can form electrostatic adsorption to form a long-chain alkyl coating effect, and the long-chain alkyl improves the lipophilicity of the inorganic filler, so that the inorganic filler has better dispersion stability; on the other hand, the distance between the sheet layers can be increased, the agglomeration phenomenon of the nano sheet layers is weakened, and the dispersion stability is further improved; in addition, in the co-processing process, the granular nano-alumina and the lamellar zirconium phosphate have stronger interface effect (both surfaces have-OH polar functional groups), and the particles can be adsorbed on the lamellar to form a composite structure, so that the dispersion of the nano-alumina is facilitated; the surface layer of the composite filler also has hexamethylene diamine molecules which are equivalent to the introduction of-NH2the-OH groups of the composite filler itself are capable of reacting with the isocyanate groups of the curing agent, and, in addition, -NH2The modified polyurethane can also react with isocyanate groups, so that the interaction between the composite filler and a polyurethane matrix is improved, and the thermal stability of the powder coating is improved; meanwhile, the uniformly dispersed lamellar also has physical barrier effect and shielding effect on corrosive media in the environment, so that the permeation of the corrosive media is slowed down, and the protective performance of the powder coating is improved; the nano alumina particles uniformly dispersed in the polyurethane matrix can improve the insulating property and the mechanical property of the coating due to stable structure, higher heat conductivity coefficient, low price and easy obtainment;
according to the powder coating, the modified polyurethane resin is used as a film forming substance, so that the powder coating has high heat resistance, can realize repeated self-repairing for many times at room temperature, and has an excellent self-repairing effect, and the self-repairing effect cannot be reduced along with the increase of the repairing times; by doping the composite filler into the powder coating, the composite filler can be uniformly dispersed in a polyurethane matrix through a series of treatments, and has stronger interaction with the matrix, so that the heat resistance, the corrosion resistance and the mechanical property of the coating are improved; the auxiliary preparation of the silicon modified hydroxyl acrylic resin can provide easy cleaning and anti-doodling performance of the coating; the powder coating obtained by the invention has excellent self-repairing performance and excellent comprehensive performance, and is suitable for the automobile industry, the ship industry, the building industry and the family decoration industry.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
A self-repairing powder coating based on polyurethane resin is prepared from the following raw materials in parts by weight: 50-60 parts of modified polyurethane resin, 6-8 parts of silicon modified hydroxyl acrylic resin, 10-14 parts of curing agent, 1-1.4 parts of flatting agent (PV88), 0.5-0.6 part of brightener (701), 0.2-0.3 part of curing accelerator (515) and 20-26 parts of composite filler;
the acid value of the silicon modified hydroxyl acrylic resin is 40-50mgKOH/g, the silicon modified hydroxyl acrylic resin is hydroxyl acrylic resin as matrix resin, the functional resin is modified by long-chain polysiloxane, one end of a molecular chain contains a reactive hydroxyl functional group, the reactive hydroxyl functional group can react with an isocyanate group in a polyurethane curing agent, and the functional resin is fixed on the surface of a polyurethane coating in a chemical bond mode and cannot migrate in the using process, so that the silicon modified hydroxyl acrylic resin has better durability; the other end of the polyurethane coating contains a polysiloxane chain segment with low surface energy, can be enriched on the surface of the polyurethane coating in the thermocuring process, has hydrophobic and oleophobic characteristics, and can provide easy cleaning and anti-doodling performance;
the modified polyurethane resin is prepared by the following method:
adding isophorone diisocyanate and polytetrahydrofuran diol in a molar ratio of 2:1 into a flask provided with a stirrer, a thermometer and a condenser, dropwise adding a proper amount of stannous octoate catalyst, heating to 80-90 ℃ under the protection of nitrogen, reacting for 2-3h, adding dendritic polyester polyol (the added amount is 1/200 of the amount of polytetrahydrofuran diol substances), reacting for 2-3h, cooling to 50-60 ℃, adding a proper amount of 2,2' -diaminoglycol diphenyl ether (the added amount is 1/180 of the amount of the polytetrahydrofuran diol substances), reacting for 1-2h, adding a proper amount of solvent (N-methyl pyrrolidone) in the whole process to reduce the viscosity of a reaction system, and finally removing the solvent in vacuum to obtain modified polyurethane resin;
taking dendritic polyester polyol as an inner core, forming polyurethane prepolymer through in-situ polymerization as an inner layer, and introducing 2,2' -diaminoglycol diphenyl ether through-NH2The modified polyurethane is prepared by grafting a dendritic polyurethane molecular chain into the reaction of the modified polyurethane with-NCO groups and then forming an outer layer through in-situ crosslinking; the formed modified polyurethane has a network skeleton mechanism, so that hydrogen bonds in the polyurethane are mutually crossed to form a stable hydrogen bond network structure, and the thermal stability of the polyurethane is obviously improved; the obtained modified polyurethane has a self-repairing function, a hydrogen bond is formed between N-H and C ═ O, so that a self-repairing process can be completed, when a coating is damaged, a new hydrogen bond is quickly formed through flowing between molecular chains, repair is realized, multiple times of repeated repair can be realized, the repair performance and efficiency are not obviously reduced along with the increase of the repair times, while the repair efficiency and the material performance are obviously reduced along with the increase of the repair times by introducing a chemical bond in the common polyurethane repair, mainly because the hydrogen bond has repeatability at room temperature, and meanwhile, the dendritic polyester polyol introduced during synthesis improves the hydrogen bond density;
the composite filler is prepared by the following method:
(1) weighing 5g of ZrOCl2·8H2O and 0.2g hexamethylenediamine in 60mL of H3PO4Stirring the solution (3mol/L) uniformly, transferring the solution into a stainless steel reaction kettle with a polytetrafluoroethylene lining, heating and reacting for 24 hours at the temperature of 200 ℃, after the reaction is finished, performing vacuum filtration, repeatedly washing the product for 8-10 times by using deionized water, drying for 24 hours in a vacuum drying oven at the temperature of 80 ℃, and grinding to obtain zirconium phosphate nanosheet powder;
(2) weighing 2.6g of nano Al2O3Adding 3.2g of zirconium phosphate nanosheet powder into a three-necked bottle filled with 155mL of ethanol water solution (mass fraction of 98%), ultrasonically dispersing for 30min, dropwise adding 1.6g of hexadecyl trimethyl ammonium bromide under the stirring condition, continuing to ultrasonically disperse, heating, stirring and refluxing the mixed solution at 80 ℃ for 6h, cooling, repeatedly washing and centrifuging, drying at 80 ℃, and grinding to obtain a filler;
the lamellar zirconium phosphate nanosheet is synthesized by a hydrothermal method, and hexamethylene diamine and-NH on the surface of the hexamethylene diamine are added in the hydrothermal synthesis process2Reacting with hydroxyl on the surface of zirconium phosphate, and grafting on a zirconium phosphate sheet layer; the zirconium phosphate nanosheets and the powder of the nano aluminum oxide are treated by the cetyl trimethyl ammonium bromide, on one hand, the cetyl trimethyl ammonium bromide and the zirconium phosphate nanosheets can form electrostatic adsorption to form a long-chain alkyl coating effect, and the long-chain alkyl improves the lipophilicity of the inorganic filler, so that the inorganic filler has better dispersion stability; on the other hand, the distance between the sheet layers can be increased, the agglomeration phenomenon of the nano sheet layers is weakened, and the dispersion stability is further improved; in addition, in the co-processing process, the granular nano-alumina and the lamellar zirconium phosphate have stronger interface effect (both surfaces have-OH polar functional groups), and the particles can be adsorbed on the lamellar to form a composite structure, so that the dispersion of the nano-alumina is facilitated; the surface layer of the composite filler also has hexamethylene diamine molecules which are equivalent to the introduction of-NH2the-OH groups of the composite filler itself are capable of reacting with the isocyanate groups of the curing agent, and, in addition, -NH2The modified polyurethane powder can also react with isocyanate groups, so that the interaction between the composite filler and a polyurethane matrix is improved, and the thermal stability of the powder coating is improved; at the same time, the uniformly dispersed lamellar corrosive medium to the environmentThe paint has physical barrier effect and shielding effect, slows down the permeation of corrosive media and further improves the protective performance of the powder paint; the nano alumina particles uniformly dispersed in the polyurethane matrix can improve the insulating property and the mechanical property of the coating due to the stable structure, higher heat conductivity coefficient, low price and easy obtaining;
the preparation method of the powder coating comprises the following steps:
firstly, weighing the raw materials according to the parts by weight, adding the raw materials into a stirring cylinder, and stirring for 4-6min under the condition of the rotating speed of 400 r/min;
secondly, pouring the mixture into a double-screw extruder, and carrying out melt extrusion, wherein the heating conditions of the extruder are that the temperature of a region I is 110 ℃ and the temperature of a region II is 125 ℃;
and step three, after the extrusion is finished, cooling to normal temperature, sending into a flour mill for milling, wherein the milling conditions are that the main milling rotation speed is 8500-.
Example 1
A self-repairing powder coating based on polyurethane resin is prepared from the following raw materials in parts by weight: 50 parts of modified polyurethane resin, 6 parts of silicon modified hydroxyl acrylic resin, 10 parts of curing agent, 1 part of flatting agent, 0.5 part of brightener, 0.2 part of curing accelerator and 20 parts of composite filler;
the powder coating is prepared by the following steps:
firstly, weighing the raw materials according to the parts by weight, adding the raw materials into a stirring cylinder, and stirring for 4min under the condition of the rotating speed of 400 r/min;
secondly, pouring the mixture into a double-screw extruder, and performing melt extrusion, wherein the heating conditions of the extruder are that the temperature of a zone I is 110 ℃ and the temperature of a zone II is 125 ℃;
and thirdly, after the extrusion is finished, cooling to normal temperature, feeding the mixture into a flour mill for milling, wherein the milling conditions are that the main milling rotation speed is 8500r/min and the auxiliary milling rotation speed is 6500r/min, and sieving the mixture through a 180-mesh sieve to obtain the powder coating.
Example 2
A self-repairing powder coating based on polyurethane resin is prepared from the following raw materials in parts by weight: 55 parts of modified polyurethane resin, 7 parts of silicon modified hydroxyl acrylic resin, 12 parts of curing agent, 1.2 parts of flatting agent, 0.55 part of brightener, 0.25 part of curing accelerator and 23 parts of composite filler;
the powder coating is prepared by the following steps:
firstly, weighing raw materials according to parts by weight, adding the raw materials into a stirring cylinder, and stirring for 5min under the condition of a rotating speed of 400 r/min;
secondly, pouring the mixture into a double-screw extruder, and performing melt extrusion, wherein the heating conditions of the extruder are that the temperature of a zone I is 110 ℃ and the temperature of a zone II is 125 ℃;
and thirdly, after the extrusion is finished, cooling to normal temperature, sending into a flour mill for milling, wherein milling conditions are that the main milling rotation speed is 9000r/min and the auxiliary milling rotation speed is 7000r/min, and sieving by a 180-mesh sieve to obtain the powder coating.
Example 3
A self-repairing powder coating based on polyurethane resin is prepared from the following raw materials in parts by weight: 60 parts of modified polyurethane resin, 8 parts of silicon modified hydroxyl acrylic resin, 14 parts of curing agent, 1.4 parts of flatting agent, 0.6 part of brightener, 0.3 part of curing accelerator and 26 parts of composite filler;
the powder coating is prepared by the following steps:
firstly, weighing raw materials according to parts by weight, adding the raw materials into a stirring cylinder, and stirring for 6min under the condition of a rotating speed of 400 r/min;
secondly, pouring the mixture into a double-screw extruder, and carrying out melt extrusion, wherein the heating conditions of the extruder are that the temperature of a region I is 110 ℃ and the temperature of a region II is 125 ℃;
and thirdly, after the extrusion is finished, cooling to normal temperature, feeding the mixture into a flour mill for milling, wherein the milling conditions are that the main milling rotation speed is 9500r/min and the auxiliary milling rotation speed is 7500r/min, and sieving the mixture by a 180-mesh sieve to obtain the powder coating.
Comparative example 1
The modified polyurethane resin in example 1 was replaced with a conventional polyurethane resin, and the remaining raw materials and preparation process were not changed.
Comparative example 2
The composite filler in the embodiment 1 is changed into zirconium phosphate nano-sheets and nano-alumina with the same mass, and the rest of raw materials and the preparation process are unchanged.
Comparative example 3
The silicon-modified hydroxy acrylic resin raw material in example 1 was removed, and the remaining raw materials and preparation process were not changed.
The powder coatings prepared in examples 1-3 and comparative examples 1-3 were subjected to performance testing by electrostatically spraying the powder coatings onto the steel plate surface, cross-linking and curing at 200 deg.C/10 min and a coating thickness of 50-55 μm;
impact resistance was measured according to the method in GB/T1732; the salt spray resistance is tested according to GB/T1771; the humidity and heat resistance is tested according to GB/T1740; self-repairing property, namely scratching the coating in the middle of the steel plate along the direction vertical to the stretching shaft, slightly applying force to two sides to enable the fracture parts to be in close contact, self-healing at room temperature, calculating self-repairing efficiency (the self-repairing efficiency H is impact resistance before scratching or after scratching), scratching three times continuously at the same position, and testing the influence of repairing times on repairing effect; measuring the contact angle of the surface of the coating by using a contact angle measuring instrument (DSA 100); the test results are given in the following table:
Figure BDA0002406517500000101
as can be seen from the above table, the impact resistance of the powder coating prepared in examples 1-3 reaches 50cm for positive impact and 50cm for reverse impact, the coating treated with wet heat for 500 hours is unchanged, the coating treated with salt spray for 1000 hours is unchanged, and the water contact angle of the coating is 104-105 degrees, which indicates that the powder coating prepared by the invention has good mechanical property, heat resistance, corrosion resistance and hydrophobic property; the repair efficiency of the powder coating prepared in the embodiments 1 to 3 reaches 69.5 to 69.8 percent, and through three repeated scratch tests, the repair efficiency is only reduced by 1 to 1.1 percent, and the reduction range is very small, which indicates that the powder coating prepared by the invention not only has excellent repair performance, but also the repair effect cannot be greatly reduced along with the increase of the repair times; compared with comparative example 1, the polyurethane subjected to modification treatment can obtain excellent self-repairing performance, and the repairing effect cannot be greatly reduced along with the increase of repairing times; compared with the comparative example 2, the composite filler can be uniformly dispersed in a polyurethane matrix through a series of treatments, and the interaction between the filler and the polyurethane matrix can be enhanced, so that the mechanical property and the corrosion resistance of the coating are improved; compared with comparative example 3, the silicon modified hydroxy acrylic resin can endow the coating with good hydrophobic property and self-cleaning property.
The preferred embodiments of the invention disclosed above are intended to be illustrative only. The preferred embodiments are not intended to be exhaustive or to limit the invention to the precise embodiments disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims (2)

1. The self-repairing powder coating based on polyurethane resin is characterized by being prepared from the following raw materials in parts by weight: 50-60 parts of modified polyurethane resin, 6-8 parts of silicon modified hydroxyl acrylic resin, 10-14 parts of curing agent, 1-1.4 parts of flatting agent, 0.5-0.6 part of brightener, 0.2-0.3 part of curing accelerator and 20-26 parts of composite filler;
the powder coating is prepared by the following steps:
firstly, weighing raw materials according to parts by weight, adding the raw materials into a stirring cylinder, and stirring for 4-6min under the condition of a rotating speed of 400 r/min;
secondly, pouring the mixture into a double-screw extruder, and performing melt extrusion, wherein the heating conditions of the extruder are that the temperature of a zone I is 110 ℃ and the temperature of a zone II is 125 ℃;
thirdly, after the extrusion is finished, cooling to normal temperature, sending the mixture into a flour mill for milling, wherein the milling conditions are that the main milling rotating speed is 8500-9500r/min, the auxiliary milling rotating speed is 6500-7500r/min, and sieving the mixture by a 180-mesh sieve to obtain powder coating;
the modified polyurethane resin is prepared by the following method:
adding isophorone diisocyanate and polytetrahydrofuran glycol in a molar ratio of 2:1 into a flask provided with a stirrer, a thermometer and a condenser, dropwise adding a proper amount of stannous octoate catalyst, heating to 80-90 ℃ under the protection of nitrogen, reacting for 2-3h, adding dendritic polyester polyol, reacting for 2-3h, cooling to 50-60 ℃, adding a proper amount of 2,2' -diaminoethylene glycol diphenyl ether, reacting for 1-2h, adding a proper amount of N-methylpyrrolidone in the whole process to reduce the viscosity of the reaction system, and finally removing the solvent in vacuum to obtain modified polyurethane resin;
the composite filler is prepared by the following method:
(1) weighing 5g of ZrOCl2·8H2O and 0.2g hexamethylenediamine in 60mL of H3PO4Stirring the solution uniformly, transferring the solution into a stainless steel reaction kettle with a polytetrafluoroethylene lining, heating the solution at 200 ℃ for reaction for 24 hours, after the reaction is finished, performing vacuum filtration, repeatedly washing the product with deionized water for 8 to 10 times, drying the product in a vacuum drying oven at 80 ℃ for 24 hours, and grinding the product to obtain zirconium phosphate nanosheet powder;
(2) weighing 2.6g of nano Al2O3And adding 3.2g of zirconium phosphate nanosheet powder into a three-necked bottle filled with 155mL of ethanol aqueous solution, performing ultrasonic dispersion for 30min, dropwise adding 1.6g of hexadecyl trimethyl ammonium bromide under the stirring condition, continuing ultrasonic dispersion, heating, stirring and refluxing the mixed solution at 80 ℃ for 6h, cooling, repeatedly washing and centrifuging, drying at 80 ℃, and grinding to obtain the composite filler.
2. The self-repairing powder coating based on the polyurethane resin as claimed in claim 1, wherein the acid value of the silicon-modified hydroxyl acrylic resin is 40-50 mgKOH/g.
CN202010163189.1A 2020-03-10 2020-03-10 Self-repairing powder coating based on polyurethane resin and preparation method thereof Active CN111303751B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010163189.1A CN111303751B (en) 2020-03-10 2020-03-10 Self-repairing powder coating based on polyurethane resin and preparation method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010163189.1A CN111303751B (en) 2020-03-10 2020-03-10 Self-repairing powder coating based on polyurethane resin and preparation method thereof

Publications (2)

Publication Number Publication Date
CN111303751A CN111303751A (en) 2020-06-19
CN111303751B true CN111303751B (en) 2022-07-22

Family

ID=71158694

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010163189.1A Active CN111303751B (en) 2020-03-10 2020-03-10 Self-repairing powder coating based on polyurethane resin and preparation method thereof

Country Status (1)

Country Link
CN (1) CN111303751B (en)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111690319A (en) * 2020-07-01 2020-09-22 江苏瑞腾涂装科技有限公司 Novel automatically cleaning plastic-coated steel pipe
CN112226197B (en) * 2020-09-17 2022-04-22 重庆重交再生资源开发股份有限公司 Modified silicone sealant for treating asphalt pavement cracks and preparation method thereof
CN112680081A (en) * 2020-12-24 2021-04-20 淮北五星铝业有限公司 Water-based mirror polyurethane coating
CN114213994A (en) * 2021-12-06 2022-03-22 甘肃宝利康耐磨材料有限公司 Wear-resistant anticorrosive coating for steel structure
CN114854295A (en) * 2022-04-14 2022-08-05 山西维力固科技股份有限公司 Polyurethane-based wear-resistant composite material and construction process
CN114933882A (en) * 2022-06-14 2022-08-23 广东菊兰新型材料科技有限公司 Durable sealant with ultrahigh elongation, high adhesion and high toughness and preparation method thereof
CN115819707B (en) * 2022-12-09 2024-01-09 畅的新材料科技（上海）有限公司 Repair layer particle for coextrusion and casting process, preparation method thereof and car cover

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103450438A (en) * 2013-09-03 2013-12-18 山东天庆科技发展有限公司 Waterborne polyurethane resin with high solid content and synthesis method thereof
CN107010611A (en) * 2016-01-28 2017-08-04 中国石油化工股份有限公司 The preparation method of Mesoporous zirconium phosphate
CN106833324A (en) * 2016-12-01 2017-06-13 天长市金陵电子有限责任公司 A kind of electrostatically sprayable type anti-corrosion powdery paints high and preparation method thereof
CN108531062A (en) * 2018-03-19 2018-09-14 安徽建筑大学 A kind of selfreparing colour polyurethane coating and preparation method

Also Published As

Publication number Publication date
CN111303751A (en) 2020-06-19

Similar Documents

Publication Publication Date Title
CN111303751B (en) Self-repairing powder coating based on polyurethane resin and preparation method thereof
CN108546337A (en) A kind of organosilicon selfreparing anti-fouling material preparation method
Wang et al. Environmentally friendly plant‐based waterborne polyurethane for hydrophobic and heat‐resistant films
Vijayan et al. Modified cardanol based colorless, transparent, hydrophobic and anti-corrosive polyurethane coating
CN111410907B (en) Self-repairing type temperature-resistant wear-resistant polyaspartic acid ester coating and preparation method thereof
CN111548731B (en) Room-temperature self-repairing polycarbonate surface coating and preparation method thereof
CN111574920A (en) Two-component marking paint composition and preparation method thereof
CN115975467B (en) High-adhesion nano anti-corrosion heat-preservation integrated coating and preparation method thereof
CN100548506C (en) Form to solidify the method that gradient is filmed and comprised the multilayer film that this curing gradient films
CN114958150B (en) Antistatic anticorrosive paint for petroleum pipeline and preparation method thereof
CN115502068A (en) Preparation method of fluorocarbon resin/polycaprolactone-based self-healing super-hydrophobic coating
CN115537114A (en) Preparation method of anionic polyurethane/cationic modified graphene composite anticorrosive coating
CN115895352A (en) Wind power blade coating combination
CN114958174A (en) Super-wear-resistant super-hydrophobic coating and preparation method and application thereof
CN114686103A (en) Super-hydrophobic composite anti-corrosion coating and construction method and application thereof
KR20140024544A (en) Environmental friendly electro-conductive urethane covalent-bonded link polysiloxane nanocomposite coating material for automobile parts and its manufacturing method
CN113583546A (en) Production process of epichlorohydrin blended rubber-plastic emulsion anticorrosive paint
CN114149742A (en) High-strength high-slip-resistance inorganic zinc silicate coating and preparation method thereof
CN111826070A (en) Wear-resistant water-based paint and preparation method thereof
CN115895414B (en) Preparation method of single-component polyurea anti-corrosion heat-insulation coating
CN117050643B (en) Water-based long-acting anti-corrosion paint and preparation method thereof
CN116515368B (en) High-temperature-resistant easy-to-clean powder coating and preparation method thereof
CN113801536A (en) Antirust coating for electric appliance rack and preparation method thereof
Xin et al. Development of fluorosilicon bivalve isocyanate microcapsules for multifunctional coatings with excellent self-repairing properties, enhanced hydrophobicity, and corrosion protection properties
CN109294427B (en) High-performance environment-friendly modified polyurea anticorrosive paint and preparation method thereof

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant