Dow 982 NSG Silicone Insulating Glass Sealant

Surface Preparation

Before using this product, clean all surfaces, removing all foreign matter and contaminants, such as grease, oil, dust, water, frost, surface dirt, old sealants or glazing compounds and protective coatings. Clean all metal, glass and plastic surfaces by mechanical or solvent procedures. Always wipe solvents on and off with clean, oil- and lint-free cloths.

Follow solvent manufacturer’s recommended safe handling instructions and applicable federal, state and local laws.

Mixing

To obtain ultimate physical properties, Dow Corning 982 Silicone Insulating Glass Sealant – Base and Dow Corning 982 NSG Curing Agent should be thoroughly mixed using an airless mixing system. As a custom feature for the customer, the cure rate may be adjusted by changing the base-to-curing agent mix ratio from 9:1 to 10.5:1 by volume (10:1 to 12:1 by weight). Sealant physical properties are not significantly changed over this range. Changes in the temperature and humidity of the environment, however, will affect snap time. Dow Corning 982 NSG Silicone Insulating Glass Sealant is compatible with existing commercial two-part silicone dispensing equipment. Neither hand-mixing nor mechanical mixing is satisfactory due to incorporation of air resulting in altered physical properties. Because of its reactivity with atmospheric moisture, Dow Corning 982 NSG Curing Agent should not be exposed to air for prolonged periods. During shutdown of mixing equipment, dispensing and mixing lines should be purged with uncatalyzed base to minimize sealant build-up. Lot matching of Dow Corning 982 Silicone Insulating Glass Sealant – Base and Dow Corning 982 NSG Curing Agent is NOT required.

Testing

Dow Corning recommends several in-house quality control tests to ensure optimum sealant performance. These tests include: Butterfly test to ensure proper mix.

Snap time or cure test to ensure expected sealant cure rate at proper mix ratio.

Tab adhesion to ensure proper sealant adhesion to production surfaces These tests should be performed every time lots of base or curing agent are changed, or every time the production line is started. Specific procedures for these recommended tests can be supplied by Dow Corning.