Abstract: What is described herein are polymerizable pyrrolidonyl 4,5-unsubstituted oxazoline monomers, homopolymers thereof, and copolymers with other monomers. A preferred polymerizable monomer compound is 2-(1-methyl-2-pyrrolidon-4-yl)-2-oxazoline. The polymers herein have excellent hydrotropic properties thus increasing the water solubility of organic compounds previously considered as water insoluble, and exhibit complexation with water soluble cosolutes.

Abstract: An aqueous process is described for preparing water-resistant coatings of hydrophobic copolymers of a predetermined composition. The hydrophobic copolymers are made from hydrophilic comonomers such as a vinyl lactam and a polymerizable carboxylic acid. The hydrophobic copolymers are rendered water soluble with a volatile neutralizing agent, such as ammonium hydroxide, then coated onto a substrate and heated to provide the water-resistant coating, and, if desired, redissolved in an aqueous alkaline solution.

Abstract: The invention relates to a hydrolysis resistant, high molecular weight polymer represented by the formula ##STR1## wherein R is alkylene having from 3 to 8 carbon atoms which is optionally substituted with lower alkyl; R.sub.1 and R.sub.2 are each hydrogen or methyl; wherein R.sub.7 and R.sub.8 are each alkylene having from 1 to 18 carbon atoms and are optionally substituted with alkyl; the sum of r and t is one or two; R.sub.4 and R.sub.5 are each independently lower alkyl; R.sub.6 is alkyl, aralkyl or alkaryl having from 1 to 8 carbon atoms or N-alkylene lactam having from 3 to 8 carbon atoms; X.sup.- is an anion derived from the group of halogen, SO.sub.3, SO.sub.4, HSO.sub.4 and R.sub.6 SO.sub.