Paraloid B-72
Description
[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.)
Applications
Risks
Talas: MSDS
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
Additional Information
Jerry Podany, Kathleen M. Garland, William R. Freeman, Joe Rogers, "Paraloid B-72 as a Structural Adhesive and as a Barrier Within Structural Adnesive Bonds: Evaluations of Strength and Reversibility" JAIC 40(1), 2001 (link).
J. Down, M.MacDonald, J.Te'treault, S.Williams, "Adhesive Testing at the Canadian Conservation Institute-An Evaluation of Selected Poly(Vinyl acetate) and Acrylic Adhesives", Studies in Conservation 41:19-44, 1996.
E. de Witte, M.Goessens-Landrie, E.J.Goethals, T.Simonds, "The Structure of 'Old' and 'New' Paraloid B72", ICOM preprints 78/16/3/1-9, Zagreb, 1978.
R.L.Feller, N.Stolow, E.H.Jones, On Picture Varnishes and their Solvents, the press of Case Western Reserve University, Cleveland, 1972.
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