[Rohm & Haas] A registered trademark for a clear, colorless, thermoplastic acrylic resin. Paraloid B-72 (formerly called Acryloid B-72 in the United States) is composed of an ethyl methacrylate (70%) and methyl acrylate (30%) copolymer. It was a shown to be a very stable resin for use in conservation (Feller 1972). Initially, Paraloid B-72 was supplied as white irregular lumps with a slight acrylic acid smell and a composition of ethyl methacrylate (68%) and methyl acrylate (28%); by 1976 the product changed to the odorless, transparent globules (de Witte et al 1978). Commercially, Paraloid B-72 is used as a general purpose coating. It produces a stable, wear resistant, nonyellowing finish. It is compatible with vinyl, cellulosic, and silicone resins. In conservation, Paraloid B-72 has been used as a coating, consolidant, and adhesive. Paraloid B-72 is supplied as solid pellets or as a 50% solids solution in toluene (Paraloid B-72 50%).
Synonyms and Related Terms
Acryloid B-72; Paraloid B72; Paraloid B-72; Acryloid B-72 (sp); Acryloid B72 (sp); Paraloid B72 (Port.)
Physical and Chemical Properties
- Soluble in toluene, xylene, acetone, carbon tetrachloride, MEK.
- Paraloid B-72 made after 1976 is soluble in ethanol.
- Slightly soluble in isopropanol.
- Insoluble in aliphatic hydrocarbons, water, oils, grease.
- Tg = 40 C
- Refractive Index = 1.479-1.489
Links to Oddy Test results posted on AIC Wiki Materials Database Pages for individual materials below
Paraloid B72 tested in 2013
Resources and Citations
- Ralph Mayer, A Dictionary of Art Terms and Techniques, Harper and Row Publishers, New York, 1969 (also 1945 printing)
- Paintings Specialty Group, Painting Conservation Catalog, Wendy Samet (ed.), AIC, Washington, DC, 1998
- Book and Paper Group, Paper Conservation Catalog, AIC, 1984, 1989
- Marie Svoboda, Conservation Survey Index, unpublished, 1997
- Conservation Support Systems, Catalog, 1997
- Product Information: Rohm and Haas acryloid acrylic resins sheet.1986
- External source or communication: CoOL DistList 2/10/2002
- Website address: www.rohmhaas.com