Sealants: These are used to provide more-or-less permanent joints between brick walls and ceilings or between marble slabs. Their main purpose is to exclude water and air. They require no structural properties, in contrast to adhesives, which bind one surface to another and must be capable of transmitting stress and strain. Better sealants are needed with greater imperviousness.

Acoustic Materials: Generally speaking, materials with good acoustic absorption do not have good moisture-absorption properties and also present a potential hazard with respect to fire safety. The best acoustic materials are not satisfactory, and further R&D work in this area is necessary.

Solar-Energy and Coating Materials: New materials are required for better solar-energy absorption, and coating transmission and reflectance properties. Current coating materials do not maintain these critical properties over a sufficiently long period of time.

Gasket Problems: This is somewhat related to the sealant problem. However, the gasket is usually coupled into a moving fixture such as a sliding door and may be subject to periodic compression and expansion. The need is for new rubberlike materials with improved resiliency and durability.

Moisture Effects: Moisture is a primary cause of deterioration in almost all classes of building materials, from concrete to metals. We need better materials that will resist the effects of moisture. Degradation of underground insulating materials due to moisture is a particularly serious problem. The corrosion of metals is another serious problem, particularly with respect to the corrosion of air-conditioning cooling towers.

The National Academies of Sciences, Engineering, and Medicine
500 Fifth St. N.W. | Washington, D.C. 20001

Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement