Lab Adhesion Testing
Dow Corning will evaluate the adhesion of our product to materials representative of those to be used on the job (i.e., glass, metal, masonry, composites, etc.) using a modified ASTM C794 peel adhesion test. All samples submitted for testing should be a minimum of 8″ (200 mm) in length. For example, for aluminum extrusions, supply one 8″ (200 mm) sample for each sealant to be tested. For glass, one standard 12″ by 12″ (300 mm by 300 mm) sample is sufficient.
Upon completion of this testing, Dow Corning will forward in writing product recommendation, surface preparation and primer recommendation (if needed). Testing takes approximately four weeks from receipt of samples. Sealant Sales can assist in the completion of the application form and submission of materials to the test lab.
Lab Compatibility Testing
Chemically incompatible glazing accessories (gaskets, spacers, setting blocks, etc.) can lead to sealant discoloration and/or loss of sealant adhesion to the substrate. To ensure a product’s suitability, Dow Corning tests the compatibility of job site representative accessory materials with its silicone sealants using ASTM Cl087. For each sealant to be tested, supply 4″ (100 mm) minimum length of the gasket, spacer or setting block. Results of the compatibility test will be forwarded in writing. Testing takes approximately four weeks from receipt of samples.
Silicone sealant will yellow when in contact with EPDM, neoprene, bitumen, asphalt and other organic-based membranes, coatings and gaskets. Dark-colored sealants will typically mask the yellowing. ASTM C1087 compatibility testing will confirm the degree of yellowing; testing may be performed with questionable materials upon request. Sealant Sales can also assist in the completion of the application form and submission of materials to the test lab.
Non-Stain Testing Information
If natural stone is being used on the project, Dow Corning can test and evaluate the performance of its sealants to determine if fluid in the sealant has the potential to migrate into porous substrates such as granite, marble, travertine and limestone. Job site representative samples of the stone need to be tested using a modified ASTM C1248 procedure.
For each stone type and sealant to be tested, supply two samples of the dimension 1″ by 3″ (25 mm by 75 mm) the thickness of the stone. Larger samples can be cut for testing. Testing takes approximately six weeks from receipt of samples. Sealant Sales can also assist in the completion of the application form and submission of materials to the test lab.