摘要 |
<p>A process for the preparation of a polymeric material that has a linear curing shrinkage of 1% or less involves mixing a liquid component containing, as its sole polymerisable constituent, one or more monomeric esters of general formula I <CHEM> wherein R is a hydrogen atom or a methyl radical and n is 1, 2, 3 or 4, with a solid component containing an acrylate polymer, a methacrylate polymer or a copolymer of these polymers, and initiating the polymerisation of the one or more monomeric esters in the liquid component. Preferred materials are tetrahydrofurfuryl methacrylate in the liquid component and polyethyl methacrylate in the solid component. The polymerisation is preferably initiated by benzoyl peroxide in the presence of a chemical activator, especially N, N - dimethyl - p - toluidine. The polymeric materials produced are particularly suitable for use in the formation of biomedical appliances, such as hearing aids, tooth filling, dental bridges and crowns, false teeth, artificial eyes and contact lenses, or for use in other biomedical applications, for example as a bone cement.</p> |