- Author
- Clifton, J. R.
- Title
- Stone Consolidating Materials: A Status Report. Final Report.
- Coporate
- National Bureau of Standards, Washington, DC
- Sponsor
- National Park Service, Washington, DC
- Report
- NBS TN 1118, May 1980,
- Distribution
- Available from National Technical Information Service
- Keywords
- construction materials; rocks; consolidation; preservatives; durability; deterioration; silicates; calcium hydroxides; barium hydroxides; silanes; polymers; acrylic resins; acrylic copolymers; vinyl resins; epoxy resins
- Identifiers
- strontium hydroxides
- Abstract
- Information on types of stone consolidating materials, their performances, and uses are critically reviewed. Processes responsible for the deterioration of stone and criteria for selecting stone consolidants are also reviewed. The main function of stone consolidants is to reestablish the cohesion between particles of deteriorated stone. In addition, a good consolidant should meet performance requirements concerning durability, depth of penetration, effect on stone porosity, effect on moisture transfer, compatibility with stone, and effect on appearance. Stone consolidants can be divided into four main groups, according to their chemistry. These groups are inorganic materials, alkoxysilanes, synthetic organic polymers, and waxes. Epoxies, acrylics, and alkoxysilanes are currently the most commonly used consolidating materials. Certain waxes have been found to have excellent consolidating abilities. Waxes, however, tend to soften and to accumulate grime and dust. Inorganic materials and some organic polymers have a tendency to form shallow, brittle layers near the surface of stone. These treated layers often separate from the untreated stone. Alkoxysilanes have excellent penetrabilities and are considered by some stone conservators as the most promising consolidating materials. However, a universal consolidant does not exist and many factors must be considered in selecting a consolidant for a specific stone structure.