| abstract |
Polymerizable compositions comprising a major amount of a first allyl functional monomer, which is an aliphatic polyol (allyl carbonate) monomer, e.g., diethylene glycol bis(allyl carbonate), and a minor amount of a second allyl functional monomer, which is an aromatic polyol (allyl carbonate) monomer, e.g., 4,4'-isopropylidenediphenol bis(allyl carbonate), are described. The second allyl functional monomer is present in the polymerizable composition of the present invention in at least an amount to provide a polymerizate of the composition having (i) reduced cracking relative to a polymerizate prepared from a comparative composition that is free of the second allyl functional monomer, and (ii) a refractive index of less than 1.530. Polymerizable compositions according to the present invention may optionally comprise static dyes and/or photochromic substances. |