Epoxy Curing Agents and Modifiers

Transcription

1 Epoxy Curing Agents and Modifiers Curing Agent DESCRIPTION curing agent is a highperformance modified polyamide intended for use with epoxy resins in two-part ambient cure coatings. Special features of this product include fast dry, good cure at low temperatures and good resistance to solvents. ADVANTAGES Fast dry time Good cure at 40 F High solvent resistance Good corrosion resistance High gloss finish Excellent development of hardness DOT noncorrosive Zero induction time at ambient temperature Good adhesion to damp concrete Moderate viscosity APPLICATIONS High-solids marine and maintenance coatings Concrete primers, coatings and bonding agents Adhesives STORAGE LIFE At least 24 months from the date of manufacture in the original sealed container at ambient temperature. Store away from excessive heat and humidity in tightly closed containers. HANDLING PRECAUTIONS Refer to the Material Safety Data Sheet for curing agent. TYPICAL CURE SCHEDULE 2 days at ambient temperature. TYPICAL PROPERTIES Appearance Slightly Turbid Amber Liquid Color (Gardner) 9 Viscosity F (cp) 3,000 Amine Value 3 (mg KOH/g) 330 Specific Gravity F.0 Density 4 (lb/gal) 8.45 Flash Point 5 ( F) >200 Equivalent Wt/{H} 4 Recommended Use Level, phr (EEW=90) 60 (EEW=500) 23 TYPICAL HANDLING PROPERTIES* Mixed Viscosity 2 (cp) 5,800 Gel Time 6 (50 g mix) (min) 65 Thin Film Set F (hr) 4.5 Thin Film Set 40 F (hr) 20 Peak Exotherm 8 (00 g mass) F 300 Peak Exotherm Time 8 (min) 65 TYPICAL PERFORMANCE* Glass Transition Temp 9 ( F) 3 Compressive Strength Yield (psi) 4,300 Compressive Modulus 0 (thousand psi) 388 Tensile Strength (psi) 9,800 Tensile Modulus (thousand psi) 403 Tensile Elongation (%) 6. Flexural Strength 2 (psi) 6,300 Flexural Modulus 2 (thousand psi) 56 Hardness 3 (Shore D) 80 Adhesion to Damp Concrete 4 (psi) day 2 F 300 day 40 F 250 * curing agent formulated with standard Bisphenol-A based (DGEBA, EEW=90) epoxy resin. Note: Please see last page for footnotes. Air Products and Chemicals, Inc., 20 Hamilton Boulevard, Allentown, PA Tel: (800) , (60) , Fax: (60) , The information contained herein is offered without charge for use by technically qualified personnel at their discretion and risk. All statements, technical information and recommendations contained herein are based on tests and data which we believe to be reliable, but the accuracy or completeness thereof is not guaranteed and no warranty of any kind is made with respect thereto. Pub. No

2 SUPPLEMENTARY DATA FAST DRY TIME As shown in Figure, the thin film dry time of curing agent with liquid epoxy resin is significantly faster than 2050 and (a conventional polyamide) curing agents. In dry time tests at room temperature, the thin film set time was reduced to 4.5 hours from hours and hours, respectively. At 40 F, the thin film set time was reduced from 46 hours for and hours for 2050, depending on use level, to 20 hours for. -based coatings can be recoated after overnight cure at 40 F. Tables 9, 0, and 2 contain preliminary formulations based on curing agent for an anti-corrosive primer, an aluminized mastic and two white gloss enamels (one low-voc formulation with liquid resin and one fast-dry formulation with solid resin). The dry-to-touch times for these formulations were all under 4.5 hours, with the primer formulation being only hour. LOW TEMPERATURE PERFORMANCE curing agent is designed to cure at temperatures as low as 40 F when used with liquid epoxy resins. It produces hard, high-gloss coatings which are highly resistant to amine blush even when cured at low temperature and high humidity. Figure 2 compares the cure development of, 2050 and curing agents at 40 F. Both and 2050 curing agents have a faster and more complete cure than the conventional polyamide, even when the conventional polyamide is accelerated with Ancamine K54 curative. The superior cure is most evident in the first 3 days of cure at 40 F, when rapid property development is needed most. Although and 2050 curing agents both show very good cure rate and degree of cure at 40 F, possesses the best balance of degree of cure and glass transition temperature, which is necessary for good coating performance. Dry Time (hrs) Figure Comparative Dry Times Cure Temperature ( o F) 2050, 0 phr 2050, 00 phr Note: Set to touch times were measured by a BK dry time recorder. (%) Cure Figure 2 40 o F Cure Profiles Note: % Cure was measured by DSC.. Cure 40 o F (days) 2050, 0 phr 2050, 00 phr

3 CORROSION RESISTANCE Formulations developed for an aluminized epoxy mastic and an inhibitive metal primer based on are detailed in Tables 9 and 0. These formulations were evaluated for salt spray resistance after 000 hours of exposure, and the results are shown in Table. Both formulations showed very good performance. ADHESION Steel Substrate The -based primer and aluminum mastic formulations were evaluated per ASTM D-454, Pull-Off Adhesion Test, for adhesion to heavy, hot rolled steel. Panels were blasted to an SSPC-SP 5 white metal quality with a mil profile of 3.0 mils. Greater than 450 psi was required for each formulation to cause failure, and all failures occurred in the adhesive. No cohesive failure in the coatings nor adhesive failure at any interface was observed. Both formulations showed good results. Concrete curing agent was tested for adhesion to damp concrete using dolly pull-off tests in accordance with ASTM D Samples were prepared by immersing blocks of ASTM C09 cement mortar in water for 24 hours. The blocks were then removed from the water, the excess water was wiped from the surface, and formulated epoxy was applied immediately. As shown in Table 3, curing agent provides excellent adhesion to damp concrete even when used in conjunction with a diluted epoxy resin at 40 F. By comparison, curing agent exhibits poor adhesion to concrete when cured at low temperatures or when used with diluted epoxy resin. Ancamine K54 curing agent is ineffective at improving the adhesion of to damp concrete. Table Salt Spray Resistance General Corrosion Scribe Corrosion Field Blistering Blister Size Aluminum Mastic Red Primer Note: 5% salt spray, cabinet temperature 95 F ASTM B-, film thickness 2.5 mils. Rating: 0 = Best, 0 = Worst Table 2 Humidity Exposure General Corrosion Blistering Degree Blister Size Aluminum Mastic Red Primer Note: Continuous 00% Humidity Exposure ASTM D-224, cabinet temperature 22 F, film thickness 2.5 mils. Rating: 0 = Best, 0 = Worst Curing Agent Table 3 Adhesion to Damp Concrete Epoxy Resin Tensile Pull Off (psi) 2 F Cure Failure Mode Tensile Pull Off (psi) 40 F Cure Failure Mode DGEBA* 300 Surface 250 Surface 90% DGEBA* 0% Epodil 48* 290 Mortar 340 Mortar DGEBA* 20 Cohesive 60 Cohesive 90% DGEBA* 0% Epodil 48* 60 Cohesive 50 Cohesive 95% DGEBA* 200 Cohesive 60 Cohesive 5% Ancamine K54 90% DGEBA* 0% Epodil 48* 40 Cohesive 40 Cohesive DGEBA: Diglycidyl Ether of Bisphenol-A (EEW=90) Epodil 48: C2 4 Alkyl Glycidyl Ether Surface Failure: Bond failure in the upper 0% of the mortar specimen Mortar Failure: Bond failure in the lower 90% of the mortar sample Cohesive Failure: Bond failure in the epoxy bond line

4 HANDLING PROPERTIES Table 4 compares the handling properties of, 2050 and curing agents. has the lowest viscosity and zero induction time, resulting in easier handling than a conventional polyamide such as. Equivalent loading compared with allows curing agent to be substituted into existing formulations with minimal modifications. FILM PROPERTIES Table 5 shows that the direct and reverse impact resistance levels for are comparable to curing agent. Gloss is superior, while VOC content in a formulated paint can be at least maintained at the same level. Table shows a white gloss enamel preliminary formulation based on liquid epoxy resin and where the VOC has been reduced to.6 lb/gal. Table 6 compares the hardness development of and 2050 curing agents with liquid bis-a resin at ambient temperature. Also shown are film appearance results under various conditions for both curing agents. -based films harden much more rapidly than those based on 2050, and the - based films develop greater ultimate hardness. Film appearance also favors in low temperature/high humidity conditions. Both curing agents give clear, tack-free film appearance at ambient temperature and moderate humidity. Table 4 Handling Properties 2050 Viscosity (cp) 3,000,000 4,000 Mixed Viscosity* 5,800 2,000 6,400 Pot Life (min)* Tack-Free 2 F)* 4.5 Tack-Free 40 F)* *Curing agents were mixed with liquid bis-a epoxy (EEW=90) at 60 phr for and, and 0 phr for Table 5 Film Properties VOC (lb/gal) Direct Impact (in/lb) Reverse Impact (in/lb) 0 2 Gloss, Note: Pigmented formulations based on solid epoxy resin (EEW=325) were mixed with each curing agent, applied to cold rolled steel panels (S) (5 mil DFT) and cured for 2 F before testing. Table 6 Hardness Development and Film Appearance Hardness Development (pendulum) 2050 day 98 5 days days 40 2 Film Appearance day, F, 50% RH clear, tack-free clear, tack-free day, 50 F, 90% RH slight haze, tacky haze, tacky day, 40 F, 80% RH clear, tacky clear, very tacky days, 50 F, 90% RH slight haze, tacky haze, tack-free days, 40 F, 80% RH clear, tacky clear, tacky Note: Clear formulations with liquid epoxy resin (EEW=90)

5 PHYSICAL PROPERTIES Table shows the superior physical properties of curing agent compared with. The high tensile strength, flexural strength and Shore D hardness show that curing agent produces harder, tougher, more resilient epoxy formulations than the conventional polyamide. CHEMICAL RESISTANCE Comparative chemical resistance levels for and curing agents are shown in Table 8. curing agent imparts significantly higher chemical resistance than curing agent, particularly to toluene. The conventional polyamide is destroyed after 3 days' immersion in toluene, while curing agent is virtually unaffected after days' immersion in toluene. -based systems have higher resistance to ethanol, 0% acetic acid and 0% sulfuric acid, particularly as the immersion time increases. Resistance to 50% NaOH is comparable to the conventional polyamide. Table Physical Properties Tensile Strength (psi) 9,0 5,00 Flexural Strength (psi) 6,300 3,900 Compressive Strength (psi) 4,20 3,00 Shore D Hardness 80 5 Note: Curing agents were mixed with liquid epoxy (EEW-90) at 60 phr and cured for days at 2 F before testing. Table 8 Comparative Chemical Resistance (5) Immersion Time Reagent (days) Toluene 3 Ethanol 3 0% HAc 3 0% H 2 SO % NaOH 3 Weight Gain (%) Destroyed.8 Destroyed Note: Curing agents were mixed with liquid epoxy resin (EEW=90) at 60 phr and cured for days at 2 F before immersion.

6 ANCAMIDE STARTING FORMULATIONS TABLE 9: ANTICORROSIVE PRIMER PRELIMINARY FORMULATION Part A lb gal Liquid DGEBA Epoxy MPA-08 (Rheox) Mix well, then add at high speed: TiPure R-900 (DuPont) Wollastekup AS (NYCO) Disperse to 5 Hegman and 25 F. Reduce speed and add: Xylene (Ashland) Totals Part B lb gal (Air Products) MPA-08 (Rheox) Beetle 26-8 (Cyanamid) Mix well at high speed, then add: Red Iron Oxide J-300 (Mineral Pigments) 6.44 Beaverwhite 325 (Cyprus) Phosplus J-0866 (Mineral Pigments) Disperse to 5 Hegman and 25 F. Reduce speed and add: Diacetone Alcohol (Union Carbide) Super High Flash Naptha (Ashland) Totals TABLE 0: ALUMINUM MASTIC PRELIMINARY FORMULATION Part A lb gal Liquid DGEBA Epoxy MPA-08 (Rheox) Wollastekup AS (NYCO) Disperse to 6 Hegman and 30 F. Epodil L (Air Products) High Flash Naptha (Ashland) Beetle 26-8 (Cyanamid) Lansford L243 (Silberline) Diacetone Alcohol (Union Carbide) Cabosil TS 20 (Cabot) 0.4 Totals Part B lb gal (Air Products) Properties: Volume Solids.9% VOC < 2.5 lb/gal PVC 2% Mixing Ratio 4: by Volume CPVC 4.% Pot Life, hr 5 PVC/CPVC.426 Dry to Touch, hr 3 Weight/gallon, Part A.29 Dry Through, hr Weight/gallon, Part B 8.45 Weight/gallon 0.3 Properties: Volume Solids.8% VOC < 2. lb/gal PVC 39.% Mixing Ratio : by Volume CPVC 54.6% Pot Life, hr 3 PVC/CPVC.25 Dry to Touch, hr Weight/gallon, Part A 4.45 Dry Through, hr 6 Weight/gallon, Part B 2.45 Weight/gallon 3.45

7 TABLE : LOW-VOC WHITE GLOSS ENAMEL Part A Grind Base lb gal Liquid DGEBA Epoxy Nuosperse 65 (Hüls America) Surfynol 40 (Air Products) Dowanol PM (Dow) TiPure R-960 (DuPont) Let Down High Flash Naptha (Ashland) Methyl Propyl Ketone (Eastman) Totals TABLE 2: FAST-DRYING WHITE GLOSS ENAMEL Part A Grind Base lb gal DER 660X80 (Dow) Nuosperse 65 (Hüls America) Beetle 26-8 (Cyanamid) Dowanol PM (Dow) TiPure R-960 (DuPont) Let Down High Flash Naptha (Ashland) n-butanol (Ashland) Totals Part B lb gal (Air Products) n-butanol (Ashland) Totals Properties Part A Viscosity 3 KU 0 KU < 2.2 lb/gal Part B Viscosity 64 KU Mix Ratio 2: by Volume Mixed Viscosity 0 KU Induction Time 0 PVC % Pot Life, hr 2 Volume Solids 0% Dry Times Set to Touch, hr 5 Dust-Free, hr Hard Dry Overnight 60 Gloss 02 Part B lb gal (Air Products) n-butanol (Ashland) Totals Properties Part A Viscosity 86 KU 80 KU < 2.8 lb/gal Part B Viscosity 64 KU Mix Ratio 4: by Volume Mixed Viscosity 80 KU Induction Time 0 PVC 5.2% Pot Life, hr 3 Volume Solids 62.2% Dry Times Set to Touch, hr 50 Dust-Free, hr 5 Hard Dry Overnight 60 Gloss 04

8 For More Information If you'd like additional information, write or call Air Products and Chemicals, Inc., at the locations below, or visit our World Wide Web Site at: Air Products and Chemicals, Inc. Performance Chemicals 20 Hamilton Boulevard Allentown, PA For Technical Info, Literature or Samples Call: or Fax: Air Products (Chemicals) Plc Clayton Lane Clayton, Manchester M 4SR England Fax: Air Products Nederland B.V. Chemicals Division Europe Kanaalweg 5 Box GD Utrecht Netherlands Fax: Air Products South Africa (Pty) Ltd 3 Protea Place Sandown South Africa Fax: Air Products Singapore Pte Ltd 9 Temasek Boulevard #08-02 Suntec Tower 2 Singapore Fax: Air Products Australia Pty Ltd 2/20 Hunter Street Parramatta NSW 250 Australia Fax: Air Products Japan, Inc. Shuwa No. 2 Kamiyacho Bldg., Fl 3-8-9, Toranomon Minato-Ku Tokyo 05 Japan Fax: Footnotes () ASTM D (2) ASTM D , Brookfield, RVTD, Spindle 4 (3) Perchloric Acid Titration (4) ASTM D (5) Seta Flash Closed Cup (6) Techne GT-4 Gelation Timer () BK Drying Recorder (8) ASTM D 24- (9) ASTM D (0) ASTM () ASTM D (2) ASTM D (3) ASTM D (4) ASTM D 454 (5) ASTM D January 998 Pub. No