Abstract: A selectively stable latex has discrete polymer particles which have present as bound charges both a pH independent charge (such as sulfonium) and a pH dependent charge of opposite polarity of the pH independent charge (such as carboxyl), wherein the two charges are present in such proportion that the latex is stable in at least one pH range and controllably unstable in at least one pH range. The latexes of the invention are extremely useful in the preparation of fibrous composites such as highly-filled composite paper and fine printing paper.

Abstract: A process is disclosed for the chemical immobilization of biological material such as bacteria and enzymes containing an active hydrogen with a vinyl addition polymer of an isocyanatoalkyl ester of an ethylenically unsaturated carboxylic acid. The vinyl addition polymer is versatile in that it can be copolymerized with varying amounts and types of comonomers.