| abstract |
The present invention relates to polymerized hydrogel adhesives, in particularnthose wherein the hydrogel is formed from monomers which include acrylamido-2-methanenpropanesulfonic acid or salts thereof (AMPS monomers) and thosenwhich contain glycerol as a humectant. In such adhesives, the levels ofnunpolymerized residual monomers, such as unpolymerized AMPS, acrylonitrile,nacrylamide and t-butyl acrylamide; and the levels of other impurities such asnacrolein, are kept very low. n The present invention also relates to a process for making hydogel adhesivesnwith very low levels of such unwanted materials. Such a process involvesnpreparation of reaction mixtures under selected pH and/or temperature conditionsnand polymerization of AMPS monomers using selected conditions of pH and UVncuring. |