Knowde Enhanced TDS
Identification & Functionality
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Applications & Uses
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- Recommended Applications
ARMORCOTE® 966 gel coats must be mixed prior to use. This includes prior to production spray application and when obtaining material for patching or any material that has been set aside for patching. Several suitable types of mixing equipment and styles of agitators are available for both pails and drums. Regardless of the specific type used, the equipment must have sufficient horsepower (relative to container size) to achieve thorough circulation from top to bottom and out to the sides of the container. The agitator must be properly sized for the container and must allow for uniform mixing regardless of the liquid level in the container.
Mixing once a day for 10 minutes is typically sufficient. Do not overmix ARMORCOTE® 966 gel coats. Overmixing can break down the polymer coating viscosity increasing the tendency to sag. Overmixing can also result in styrene loss which could contribute to porosity. Air bubbling should not be used for mixing. It is not effective and only serves as a potential source of water or oil contamination.
Metallic gel coats are formulated for spray application. Brushing or rolling is not recommended. Flakes of aluminum, bronze, coated mica, copper, glass, iron oxide, and thermoplastic or thermoset plastic are used to impart metallic effects. Type, size, concentration, orientation, transparency and opacity of the flakes, along with the presence of dyes or pigments, contribute to the overall color and appearance of metallic gel coats.
Changes in the setup of the spraying equipment and/or application technique lead to different metallic color shades and patterns. To reproduce the metallic color, it is essential that the following be kept constant: spray equipment, pot pressure, atomization pressure, and distance at which the spraying is done.
If the patterns of the metallic gel coat on the finished part are not satisfactory, a dust coat approach could be used. The dust coat should be consistent and uniform. A heavy dust will yield a different effect than a light dust. If the gel coat is sprayed to an extremely inconsistent dust coat, the different effects will be noticeable. Three to four minutes interval should be allowed before the final spray is applied to achieve the desired film thickness.
For optimum results, uniform catalyst mix must be achieved. Even with the equipment properly calibrated, potential problems can occur due to: poorly atomized catalyst; surging problems (gel coat or catalyst); poor tip alignment (catalyst to gel coat mix); contamination; and poor application procedures, which will quickly negate all benefits of calibration. The equipment (and application procedures) must be monitored on a routine basis to ensure proper application and cure of the gel coat. Ask about and adhere to all equipment manufacturers’ recommendations.
For best overall performance properties, a wet film thickness of 18 ± 2 mils is recommended as ideal. Films less than 12 mils may not cure properly, may be hard to patch, have more print-through, and be more susceptible to water blisters. Films above 24 mils may pre-release, trap porosity, crack and are more subject to weathering discoloration. If weathering (yellowing from sunlight, decks) is of great concern, thinner films (12 to 16 mils) would perform better, but patchability, print-through and blister resistance could suffer.
Proper mold maintenance is important. Minimal repair work is always desirable. Sanding and compounding can hasten the chalking and loss of gloss of all gel coats. Patching metallic gel coats is very difficult and patches will likely be more noticeable than those for solid colors. Fabricators may have to be content with some color and appearance differences between the patch and surrounding area, due to the sanding/polishing disturbance of the metallic pigments.
Properties
- Typical Properties
| Value | Units | Test Method / Conditions | |
| Viscosity (77°F) | 14500 | cps | — |
| Thixotropic Index (77°F) | 5.5 | — | — |
| Weight per Gallon (77°F) | 10 | lbs | — |
| Flash Point (77°F) | 79 | °F | — |
| Gel Time (77°F) | 15.5 | minutes | — |
| Lay-up Time (77°F) | 67.5 | minutes | — |
| Sag Resistance (77°F) | Good @ 24 mils wet | — | — |
| Hide (77°F) | Normally complete @ 10 mils | — | — |
Technical Details & Test Data
- Cure
It is recommended that gel time be checked in the customer's plant because age, temperature, humidity and catalyst will produce varied gel times. All data referencing gel or cure refers specifically to Arkema Luperox® DDM-9 catalyst. United Initiators NOROX® MEKP-9 and NOROX® MEKP-9H, Akzo Nobel CADOX L-50a and CADOX D-50 are expected to yield similar performance. Arkema Luperox® DHD-9, NOROX® MEKP-925 and NOROX® MEKP-925H, and Chemtura HP-90 may yield slightly shorter gel and cure times.
The catalyst level should not exceed 3.0% or fall below 1.2% for proper cure. Recommended range is 1.2% to 3.0% with 1.8% at 77°F being ideal. Normally, the gel coat film is ready for lamination in 45 to 90 minutes. This time element is dependent on material temperature, room temperature, humidity, air movement, and catalyst concentration. Special fast-cure versions are available but must be requested. These products offer lay-up times of 30 minutes or less depending on gel times. Fast cure products have shorter stability and should not be inventoried more than 45 days.
These products (standard or fast cure) should not be used when temperature conditions are below 60°F, as curing may be adversely affected.
Safety & Health
- Product Safety
Metallic gel coats may contain aluminum pigments. Precautions of aluminum pigment-containing products must be exercised. Wearing gloves is recommended when working with these products. Small spills and drops should be cleaned immediately before the concentrate contaminates and spreads in the working area. All equipment should be well grounded. Chlorinated solvents in contact with aluminum can cause an explosion; refrain from cleaning the metallic spray equipment with such solvents.
Storage & Handling
- Handling and Storage
ARMORCOTE® 966 gel coats will have a shelf life of 60 days depending on the type of metallic pigment used. All shelf lives are from the date of manufacture. Consult a Polynt Composites representative for the shelf life of a particular product