Paint Technical Training

June 1, 2018 | Author: stdshop | Category: Paint, Corrosion, Acrylic Paint, Epoxy, Anode
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PAINT TECHNICAL TRAININGCORROSION CELL CURRENT-CARRYING ELECTROLYTE (SEAWATER, SOIL, ETC.) ANODE (CORRODING AREA) CATHODE (NONCORRODING AREA) IONIC PATH schematic of a corrosion cell CATHODE ELECTRON ANODE REACTION PATH REACTION Corrosion cell will stop if any reaction or path is stopped NEW PIPE OLD PIPE ANODE CATHODE -OTHER CELLS . TANK DRAINAGE POOR POOR GOOD . PAINT BEHAVIOUR OVER SURFACE IRREGULARITIES IRREGULARITY SHARP CORNERS & EDGES INSIDE CORNERS PROBLEM INSUFFICIENT THICKNESS CRACKED OR SPONGY COATING CORRECTION GRIND TO 1/4 IN. MINIMUM RADIUS FILLET WELD & GRIND TO 1/2 IN. MINIMUM RADIUS INSUFFICIENT THICKNESS CRACKED OR SPONGY PROJECTIONS PITS CREVICES GRIND FLUSH FILL WITH WELD METAL & GRIND FLUSH ENTRAPPED AIR . GALVANIC SYSTEM OF CATHODIC PROTECTION METAL RECEIVING PROTECTION CURRENT-CARRYING ELECTROLYTE GALVANIC ANODES . IMPRESSED CURRENT SYSTEM OF CATHODIC PROTECTION (-) METAL RECEIVING PROTECTION CURRENT-CARRYING ELECTROLYTE REMOTE ANODE GROUND BED (+) RECTIFIER . PAINT IS A BARRIER FROM Sun Oxygen Salt Water . PINPOINT RUSTING RUSTING WILL OCCUR HERE STEEL COATING STEEL . INHIBITION BY ZINC PRIMER INHIBITIVE COATING CONCEPT Break in coating to steel surface Moisture absorbtion into film (moisture previous coating) Moisture allows zinc to ionize Ionization of inhibitor Cathodically protecting steel Reaction with steel surface Tight adhesion prevents coating undercut ZN ++ Passive layer 2nd organic topcoat 2nd coat 1st organic topcoat 1st coat Inorganic zinc permanent primer STEEL Inhibitive primer STEEL . THREE COMPONENTS OF PAINT SOLVENT RESIN PIGMENT SOLVENT VEHICLE RESIN FILM SOLIDS PIGMENT FUNCTION OF PIGMENT Provide opacity Provide colour Improve weather resistance Increase paint adhesion Decrease moisture permeability Control gloss WET PAINT VEHICLE SOLVENT PIGMENT RESIN PRIMARY SECONDARY PIGMENT PIGMENT . RELATIONSHIP OF PAINT RESIN/PIGMENT RATIO TO GLOSS HIGH-GLOSS SEMI-GLOSS FLAT SOLVENT* SOLVENT* SOLVENT* RESIN RESIN PIGMENT PIGMENT PIGMENT RESIN RESIN RESIN PIGMENT PIGMENT HIGH MODERATE RESIN/ RESIN/ PIGMENT PIGMENT * Amount of solvent may vary greatly RESIN PIGMENT LOW RESIN/ PIGMENT WET PAINT CURED PAINT CROSSSECTION OF CURED PAINT . A PAINT FILM MUST BE: SUBSTRATE Easy to apply Continuous and uniform Tightly adhering Impermeable Weather resistant . THREE METHODS OF PAINT CURING Air oxidation Solvent or water evaporation Chemical reaction of components . AIR OXIDATION OF PAINTS LIQUID DRYING OIL OXYGEN SOLID FILM OF DRYING OIL . generally soft and slow drying cannot be used in immersed zone Alkyd Good wetting.PROPERTIES OF AIR DRYING COATINGS Generic (chemical) type Properties Oleoresinous Good wetting. may be hard or soft. cannot be used in immersed zone Silicone alkyd Improved durability and gloss. cannot be used in immersed zone Phenolic Can be used in immersion service . CURING OF LACQUERS AND WATER EMULSIONS SOLID RESIN IN SOLVENT OR WATER EV AP O RA TIO N SOLVENT FUMES OR WATER VAPOR SOLID RESIN UNCHANGED CHEMICALLY . poor wetting Polyvinyl acetate Same as acrylic . of limited use. easily touched-up or topcoated Chlorinated rubber Good water. limited solvent resistance. frequently on mechanically cleaned surfaces Polyvinyl butyral Used exclusively in pretreatment (wash) primers for drying oil and vinyl coatings WATER BASED COATINGS Acrylic Used in atmospheric area only. durable easily touched-up or topcoated Coal tar and asphaltic Soft.PROPERTIES OF COATINGS THAT CURE BY SOLVENT OR WATER EVAPORATION Generic (chemical) type Properties SOLVENT BASED COATINGS Vinyl (polyvinyl chloride) Good water. limited solvent resistance. black. CURING OF PAINTS BY CHEMICAL REACTION LIQUID LIQUID LIQUID RESIN A RESIN B RESIN A-B . used in pre-construction primers. black only. difficult to topcoat Polyester Frequently used with glass fibres to give tough. topcoated for use in immersed zone . water resistant coating or glass flakes to impart abrasion resistance Inorganic zinc Good abrasion resistance.PROPERTIES OF CHEMICAL REACTING COATINGS General (chemical) type Properties Epoxy Good water and chemical resistance. aliphatic urethanes weather well in sunlight. difficult to topcoat Coal tar epoxy Excellent water resistance. chalk freely. difficult to topcoat Urethane Good water and solvent resistance. ) . build. pot life etc.COATING PROPERTIES RELATED TO CHEMISTRY Mechanism and time of curing Performance in different environments Performance on different substrates Compatibility with other coatings Ease of top coating and repair Flexibility and toughness Application properties (wetting. THE TOTAL QUALITY OF A COATING SYSTEM IS ONLY FOR 50% DEPENDING ON THE PAINT ITSELF. . .75% OF PAINT FAILURES ARE CAUSED BY IMPROPER SURFACE PREPARATION. SURFACE PREPARATION REQUIREMENTS Proper construction Proper degree of cleanliness Proper profile height (texture) REPAIRS/MODIFICATIONS REQUIRED BEFORE SURFACE CLEANING Steel welding, cutting, grinding of welds and edges, filling crevices Wood replacement, cutting, nailing Concrete/Masonry patching, filling cracks and pores Plastic cutting, bonding RULE OF THUMB The profile height of steel should be between 1/2 and 2 1/2 mills and never more than one-half the primer dry film thickness Rz PROFILE VALUE Z1 Z2 Z3 Z4 Z5 . COMMON METHODS OF CLEANING SURFACES FOR PAINTING Hand and power tools Flame Solvent Steam Water blast Abrasive blast . 35 linear feet per minute Wear goggles. helmet Remove all sources of flammable gases . old paint Follow with wire brushing or scraping Warms and dries surface Slow: 15 . gloves.FLAME CLEANING 300º F. loosens mill scale. grease.SOLVENT WASHING Removes oil. dust Use clean rags Turn and replace often Replace solvent for final rinse Wear goggles and gloves . BLASTING HAS LIMITATIONS Removal oil/grease Removal thermoplastic materials Dust problems Chemical waste . CLEANING METHOD CONTAMINANT Solvent cleaning Steam Grease / Salt / Dirt Oil / Weldmarks Waterblasting Marine growth / Loose paint Hand or power tools Loose mill scale / Weld flux / Loose rust / Weld splatter / Loose paint Flame cleaning followed by wirebrushing Rust Loose mill scale / some tight millscale Abrasive blasting All visible rust / Tight paint Tight mill scale / Foreign matter . pretreatment (wash) prime * Solvent wash to remove oil or grease .RECOMMENDED CLEANING METHODS FOR VARIOUS SUBSTRATES * Wood sanding after scraping loose paint Plastic sanding after scraping loose paint Concrete/Masonry careful waterblasting Steel abrasive blasting generally preferred over mechanical cleaning Aluminium/Tin/Copper/Brass/Galvanized steel mechanical cleaning or brush off blast. etc Significant environmental factors . space.CRITERIA FOR COATING SELECTION Desired coating properties Nature and condition of substrate Basic function of coating Limitations of time. equipment. 55% 35 .45% 10 .15% .STEEL PAINTING COSTS SURFACE PREPARATION PAINT APPLICATION PAINT MATERIAL 40 . slow drying. other properties may vary Silicone Alkyd Good wetting and gloss Latex Poor wetting. easily applied and cleaned up Exterior wood (vinyl or acrylic) .COATINGS COMMONLY USED ON WOOD Substrate Paint Comments Interior wood Oil Slow drying and relatively soft Alkyd May be hard or soft Latex (vinyl or acrylic) Can be applied over oil. alkyd or latex primer Oil Good wetting. soft Alkyd Good wetting. COATINGS COMMONLY USED ON MASONRY AND CONCRETE SURFACES Interior masonry. plaster. must remove all loose chalk Same as acrylic latex Good for waterproofing Fill coats will reduce water penetration Vinyl latex Same as acrylic latex Chlorinated rubber. Good for waterproofing. Epoxy concrete in corrosive conditions . for Vinyl. and wall board Acrylic latex Exterior concrete. and masonry Acrylic latex Vinyl latex Chlorinated rubber Easily applied. easily touched up Good durability.COATINGS COMMONLY USED ON IRON AND STEEL SURFACES Substrate Interior iron and steel Paint Alkyd Vinyl Epoxy Urethane Exterior iron and steel Comments Not for immersed surfaces Good water. better gloss retention Inorganic zinc Topcoated with epoxy for seawater immersion. poor solvent resistance Good durability and chemical resistance Good durability and chemical resistance Alkyd Silicone Alkyd For mild and marine environments Same as Alkyd. tankcoatings Vinyl Epoxy Urethane Good durability. chalks in sunlight Aliphatic type has good weathering . including poorly prepared surfaces Easy to apply Good gloss retention .ALKYD Advantages One-package coating Disadvantages Good exterior durability Poor chemical and solvent resistance Moderate cost Poor water resistance Good flexibility Poor resistance to alkalinity Excellent adhesion to most surfaces. repair Environmental acceptability Disadvantages Limited durability outside Poor chemical and solvent resistance Poor immersion resistance Curing temperatures must be above 50º F . topcoat.LATEX (Acrylic or Vinyl) Advantages Moderate cost Good flexibility Easy to apply. BITUMINOUS Advantages Disadvantages Low cost Poor weathering properties Good moisture barrier Good corrosion protection Good film build Black color only Poor solvent resistance . VINYL (Acrylic) Advantages Disadvantages Rapid drying and recoating Poor solvent resistance Excellent durability Low film build per coat Excellent durability Very good gloss retention Applicable at low temperatures . CHLORINATED RUBBER Advantages Disadvantages Rapid drying and recoating Poor solvent resistance Fair chemical resistance Poor heat resistance (158º F) Poor gloss retention Good water resistance Good durability Applicable at low temperatures Easy to repair . limited potlife Curing temperatures must be above 50º F Poor gloss retention Film chalks on ageing Roughening up required for repair . slick film Excellent adhesion Excellent abrasion resistance Good caustic resistance Disadvantages Two-package coating .EPOXY Advantages Excellent chemical and solvent resistance Good water resistance Very good exterior durability Hard. COAL TAR EPOXY Advantages Excellent resistance to fresh and salt water Good film build Excellent resistance to aliphatic petroleum products Disadvantages Chalking Topcoating may present problems (tar bleeding) . limited pot life High cost Personal protection required .POLYURETHANE Advantages Excellent gloss retention Can be applied at low temperatures Excellent durability in exterior exposure Recoatable Disadvantages Gloss drop with high humidity during drying Two component . ORGANIC ZINC Advantages Excellent corrosion protection Provides "galvanic" protection Easier to topcoat than inorganic zinc (less porous) One or two-package depending upon organic resin Disadvantages High cost Spray application only Constant stirring necessary during application Not suitable for acidic or caustic service Zinc salts to be removed . depending on type Constant stirring necessary . skilled applicators required Not suitable for acidic or caustic service Requires careful selection of tiecoats and topcoats Drying influenced by humidity .INORGANIC ZINC Advantages Excellent corrosion protection Excellent exterior durability Excellent heat resistance Provides "galvanic" protection properties Provides "permanent" primer capability when used in conjunction with proper topcoats and/or maintenace practices Excellent solvent resistance Disadvantages High cost Spray application only. FACTORS AFFECTING SELECTION OF METHOD OF COATING APPLICATION Characteristic Brush Roller Spray Speed Ease of application Simplicity of equipment Safety Material conservation Portability Versatility Initial economics Long range economics Hiding power Uniformity fair fair excellent excellent excellent excellent good excellent fair good poor good good excellent excellent good good fair excellent fair fair fair excellent poor poor poor poor/good* poor excellent poor excellent poor/good* good * varies with equipment and operator . .000 sq. ft. ft. ft. Air Spray 4 - 8. Roller 2 - 4.000 sq.12. ft.000 sq.000 sq.METHOD (square feet applied per 8 hour day) Brush 1. Airless Spray 8 . THREE FACTORS AFFECT PAINT VISCOSITY Solvent / solids ratio Paint temperature Paint mixing . VISCOSITY VISCOSITY (SECONDS) 80 50 30 20 0 50º 70º 95º TEMPERATURE ( º F) 125º .TEMPERATURE VS. if any : ratio of catalyst to base paint. and pot life .MIXING AND THINNING PROCEDURE One-package paints Two-package paints : type and amount of thinner to be used. induction time. . PROPER OVERLAPPING TECHNIQUE Overlap strokes by 50% for uniform film build . ....36" wide .PROPER STROKING TECHNIQUE.36" 4" overlap Divide a long surface area into sections 18" .36" 4" overlap 18" .36" 18" .. SECTIONING A LARGE SURFACE 18" .. PAINT INSPECTION DUTIES Inspection of materials Inspection of surface preparation Inspection of paint application Final inspection for acceptance . PROPER STORAGE OF PAINT NO Flames Sparks Direct sun YES Temperature control Stock rotation On pallets Ventilation . Oil or grease contamination Poor adhesion creates areas where moisture vapour can condense or the vapour pressure in the void may be greater than exterior water pressure causing blisters and eventual coating disruption STEEL . BUBBLE OF TROUBLE PAINT BLISTER FORMED BY SOLVENT ENTRAPPED BETWEEN COATS VAPOR FROM SOLVENT TRYING TO ESCAPE PRIMER COAT TOP COAT STEEL WALL SECOND COAT . SURFACE PREPARATION SPECIFICATIONS SSPC-Guide to Vis 1 Pictorial surface preparation Standards for painting steel surfaces SSPC-Guide to Vis 2 Standard method of evaluating degree of rusting on painted steel surfaces SSPC-SP 1 Solvent cleaning SSPC-SP 2 Hand tool cleaning SSPC-SP 3 Power tool cleaning SSPC-SP 5 White metal blast cleaning SSPC-SP 6 Commercial blast cleaning SSPC-SP 7 Brush-off blast cleaning SSPC-SP 8 Pickling SSPC-SP 10 Near-white blast cleaning . and the shadowing from blast cleaning patterns SSPC-Vis 1 or other visual standards of surface preparation agreed upon by the contracting parties may be used to further define the surface .APPEARANCE OF THE COMPLETED SURFACE The surface shall be roughened to a degree suitable for the specified paint system The completed surface shall be cleaned to a grey-white metallic colour. original surface condition. The appearance of the surface may be affected by the particular blasting abrasive used Uniformity of colour may be affected by the grade. and configuration of the material being cleaned. as well as by discolourations from mill or fabrication marks. SSPC-SIS SSPC-spec. dirt. (At least 95% free) Commercial 3 SSPC-SP 6 CSa2 At least two-thirds free of visible residues Brush-off 4 SSPC-SP 7 CSa1 Only tight mill scale and tightly adhering rust after blasting . streaks or discolouration. Description White metal 1 SSPC-SP 5 CSa3 Grey-white colour 100% free of oil. grease. mill scale and paint Near white 2 SSPC-SP 10 CSa2½ Only very light shadows.SURFACE PREPARATION SPECIFICATIONS FOR ABRASIVE BLAST CLEANED STEEL Surface Visual standard SSPC-Vis 1 NACE Spec. rust. FOUR RUST GRADES OF UNPAINTED STEEL Adherent mill scale Rusting mill scale Rusted Pitted and rusted . 10 0.70 0.HAND TOOL POWER TOOL COMMERCIAL BLAST NEAR WHITE BLAST WHITE BLAST 0 0.00 1.30 0.50 0.20 0.80 0.60 0.40 0.10 TOTAL COST IN DOLLARS PER SQUARE FOOT .90 1. Intended use Solvent cleaning SSPC-SP1 Removal of oil.no. rust. grease.OTHER STEEL STRUCTURES PAINTING COUNCIL SURFACE PREPARATION SPECIFICATIONS SSPC specification Spec. scraping. electrolysis or both . and coating by other methods Hand tool cleaning SSPC-SP2 Removal of loose mill scale. rust and coating by hand sanding. chipping or other impact tools Flame cleaning of new steel SSPC-SP4 Preparing unpainted steel with oxy-acetylene flame followed by wire brush removal of loosened mill scale and rust Pickling SSPC-SP8 Preparing metal surfaces for coating by removal of mill scale and rust by chemical reaction. and other soluble materials prior to removal of mill scale. STEEL SURFACE PREPARATION REQUIREMENTS FOR COMMONLY USED COATINGS Coating type Minimum surface preparation Drying oil Alkyd Oleoresinous Phenolic Coal tar Asphaltic Vinyl Chlorinated rubber Epoxy Coal tar epoxy Urethane Organic zinc Inorganic zinc Hand or power tool cleaning (SSPC-SP2 or 3) Commercial blast (SSPC-SP6) Commercial blast (SSPC-SP6) Commercial blast (SSPC-SP6) Near white or commercial blast (SSPC-SP10 or 6) Near white or commercial blast (SSPC-SP10 or 6) Near white or commercial blast (SSPC-SP10 or 6) Near white or commercial blast (SSPC-SP10 or 6) Near white or commercial blast (SSPC-SP10 or 6) Near white or commercial blast (SSPC-SP10 or 6) Near white or commercial blast (SSPC-SP10 or 6) White or near white (SSPC-SP5 or 10) . COMPRESSOR HP COMPRESSOR CAPACITY CFM RATING (electric drive) 15 20 25 30 40 50 60 75 100 50 70 90 up up up up up up to to to to to to 70 90 105 130 170 210 260 320 420 . 80 psi 78 % approx. 70 psi 60 % 60 psi 50 % .NOZZLE PRESSURE 100 psi CLEANING RATE 100 % (Standard for comparison) 90 psi 82 % approx. 2 3.2 0.3 2.6 * Pressure drops for other lenghts in direct proportion to change in length .6 2.4 1.9 11.6 0.1 - 0.2 0.3 1.4 0.4 2.4 0.5 2.9 3.6 0.6 0.5 1.5 2.9 1.4 1.4 1. LENGTHS 40 60 100 120 150 80 LOSS OF PRESSURE PSI* 60 80 100 110 1.7 0.3 1.9 60 80 100 110 - 0.4 0.2 0.2 0.8 6.0 1.3 0.0 1.6 0.PRESSURE LOSS IN AIRHOSE DUE TO FRICTION HOSE SIZE.0 0.4 8.6 5.0 0.6 5.3 7.5 0.2 0.7 2.2 3.6 0.8 4.3 5.1 9.1 60 80 100 110 - 0.0 0.8 0.8 1.4 3.6 2.9 8.8 0.3 0.2 0. LINE COUPLED PRESSURE END PSI 3/4" 1 inch 1-1/4" CFM FREE AIR PASSING THROUGH 50 FT. choose the short blast hose.RULE OF THUMB Bigger and shorter are the key to blast hose efficiency. . If a choice must be made between having a short air hose or a short blast hose. RIGHT…… EXTERNALLY-FITTED QUICK COUPLING WRONG…… INTERNALLY-FITTED COUPLING . RULE OF THUMB A loss of pressure at the nozzle of only 10 PSI means a 15% loss in production . Bigger is not better here.RULE OF THUMB Choose the smallest grain size which can remove the contaminant on that particular surface. . RULE OF THUMB It only takes one spray painter to keep up with four blasters . AIR SPRAY FEATURES Finest atomization & finish Versatile Easy to use . POWER SOURCE Electric Gas Air . AIRLESS SPRAY FEATURES Reduced overspray & bounce-back Increased production Material savings Labor savings Energy savings Improved coverage . 021 2000 2200 Phenolic.029 900 Organic zinc . amine .1800 .017 . modified .023 .013 " tip 2200 Chlorinated rubber 2200 Epoxy polyamide .031 900 Coal tar epoxy .026 ..015 .. modified .015 Vinyl.031 psi 2000 2000 2400 ...025 2200 Antifouling .017 .013 .021 Inorganic zinc .1800 .TYPICAL AIRLESS TIP SELECTION Paint type Orifice size Pressure Acrylic. copolymer Epoxy..019 . EXTERNAL IONIZATION CHARGED PROBE . ELECTROSTATIC SPRAY FEATURES Increased transfer efficiency Fewer passes Wrap around edges & irregular surfaces . Lower material usage Fewer rejects Reduced labor (greater productivity) . SAFETY HAZARDS IN PAINTING OPERATIONS High places High pressures Flammable materials Toxic materials . HAZARDOUS MATERIALS IN SURFACE PREPARATION Acids Alkalis Steam Particulate matter in blasting dusts Lead and other toxicants from old paint in blasting dust . ) Toxic or allergic resins (urethane. etc. etc. epoxy.) . chromium.HAZARDOUS MATERIALS IN PAINT APPLICATIONS Flammable solvents Toxic pigments (lead. V.MAXIMUM ALLOWABLE CONCENTRATIONS OF SOLVENT VAPORS (MAC) Type of solvent Acetone Alcohols Butyl Ethyl Isopropyl Methyl (Wood) Benzene (Benzol) Carbon Tetrachloride Cellosolve Butyl Cellosolve Cellosolve acetate Methyl cellosolve Methyl cellosolve acetate Cyclohexane Cyclohexanone Threshold limit value (TLV)* 1000 100 1000 400 700 25 10 200 50 100 25 25 300 50 * For 8 hours exposure. Perchloroethylene Toluene (Toluol) Trichloroethylene Turpentine Xylene (Xylol) 400 200 50 500 700 100 500 200 500 100 200 100 100 200 . PPM by volume in air Type of solvent Threshold limit value (TLV)* Cyclohexene Enamel thinner Ethylene dichloride Methylene chloride Methylene ketone (MEK) Methyl isobutyl ketone (MIBK) Mineral spirits Naphta. coal tar Naphta.M & p. dirt. scale particles Abrasive blast cleaning Toxic fumes from paints or solvents Flame cleaning Solvent cleaning .RESPIRATORS Protection from: During: Dust Sandblasting Rust. FLASHPOINT AND EXPLOSIVE LIMITS OF PAINT SOLVENTS Type of solvent Acetone Alcohol.2 0. methyl Cyclohexane Cyclohexanone Cyclohexene Ethylene dichloride Methylethyl ketone (MEK) Methyl isobutyl ketone (MEK) Mineral spirits Naphtha. ethyl Alcohol.7 -1.8 1.0 --8.1 -6.7 0.4 (non-flammable) 0.0 6.3 .8 1.5 (non-flammable) 2. butyl Alcohol.8 1.0 6.0 9. acetate Cellosolve.5 3.8 11.3 2.3 1.0 12. & P.9 11.7 none 5.2 1. isopropyl Benzene (benzol) Carbon Tetrachloride Cellosolve Cellosolve.8 1.4 115 60 67 12 none 135 130 120 32 129 22 70 35 75 105-110 40-60 45 none 95-100 80 Explosive limits % by volume in air Lower Upper 2. Toluene (toluol) Trichloroethylene Turpentine Xylene (xylol) Average flash point degrees F . V.0 --15.5 1.M.6 1.0 6.0 12.0 16.2 19.0 8. GROUNDING Spray gun Object being painted . TARGET FOR SAFETY PROGRAM Complete safety training Use of safety equipment Available emergency services Constant worker vigilance . Chemically drying binder agent + solvent Wet coat of paint Beginning drying (+ solvent vapour) THE SUBSEQUENT CHEMICAL REACTION CAN TAKE PLACE IN THE FOLLOWING WAYS: B B B B B 1. 2. 5. 4. with the aid of oxygen from the atmosphere with the aid of heat with the aid of a hardener with the aid of a catalyst with the aid of moisture from the atmosphere Dry coat of paint (with newly formed macromolecule) . 3. PHYSICALLY DRYING PAINT (schematic illustration) BINDING AGENT WET COAT OF PAINT + SOLVENT = PAINT DRY COAT OF PAINT (+ SOLVENT VAPOUR) . MIBK Methyl-. Butyl- Ethers Glycolethers . MEK.SOLVENTS / THINNERS Generic type Aliphatic Aromatic Petrol White spirit Xylene Toluene Naphta's ) Bitumen ) ) ) Bit and tar ) Alcohols MethylEthylPropylButyl- Ketones Esters Acetone. EthylPropyl-. TYPE OF PAINTS Epoxies Polyurethanes Chlorrubbers Vinyls Alkyds ACID + ALCOHOL ALCID ALKYD . BINDER FUNCTIONS Adhesion Gloss Viscosity Protection weather water chemicals Mechanical properties: strength flexibility hardness Filmforming . great robustness. Good binding. plastic on heating Thermoplastics Elastomers Thermosetting plastics Linear macromolecules with a single cross-linkage. on heating sometimes plastic. Hard at room temperature. Hard at room temperature. little binding Poor film forming capacity Linear macromolecules. unchanged on heating . Rubbery at room temperature. not deformable.Small molecules low viscosity Large molecules high viscosity Small molecules. mostly unchanged Net-shaped macromolecules with many cross-linkages. good deformability. Good binding good elasticity. Good binding.


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