C. R. Lovell, R. Rycroft, D. M. J. Williams
Feb 1, 1985
Citations
2
Influential Citations
14
Citations
Journal
Contact Dermatitis
Abstract
A company had been involved in the manufacture of hydroxypropyl methacrylate for 2 years and hydroxyethyl methacrylate for 3 months before beginning the manufacture of hydroxypropyl acrylate (HP A). These hydroxy monomers are used in polymeric paint formulations for modern car paint systems. The hydroxy ethyl and propyl methacrylates are produced by the catalysed esterification of the corresponding methacrylic acid with either ethylene or propylene oxides and purified by distillation. Typical purities are in excess of90 % with the major impurities being diesters and dendro products (formed by reaction of 2 or more molecules of the alkylene oxide with the acid). Minor impurities include the parent acid. A phenolic inhibitor, p-methoxy phenol (mono-methyl ether of hydro quinone), is present at several hundred ppm to control adventitious polymerisation. Even so, a small amount of polymer is formed in the process equipment and has to be removed manually from a flanged basket strainer incorporated into the pipeline