Accession Number:

ADA027556

Title:

Water-Vapor-Barrier Coatings for Polyurethane Foams

Descriptive Note:

Technical memo.

Corporate Author:

HARRY DIAMOND LABS ADELPHI MD

Personal Author(s):

• Boyd, J. M.
• Van Daalen, David

Report Date:

1976-06-01

Pagination or Media Count:

16.0

Abstract:

The water-vapor transmission rates through a polyether type of polyurethane foam with and without vapor-barrier coatings were determined at 70 C and 91-percent relative humidity. The data indicate that polyurethane foam encapsulation cannot provide satisfactory protection from moisture penetration. The moisture transmission is more severe for low-density foam. Two low- molecular-weight, butyl-rubber coating materials and one epoxy compound were shown to form good coatings on the foam and resulted in 37- to 95-percent transmission-rate reductions when the coatings were nominally 0.020 in. thick.

Descriptors:

• *POLYURETHANE RESINS
• *PROTECTIVE COATINGS
• *WATER VAPOR
• HUMIDITY
• POLYETHERS
• FOAM
• BUTYL RUBBER
• MOISTURE
• INSULATION
• EPOXY RESINS

Subject Categories:

• Coatings, Colorants and Finishes
• Plastics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE