Fundamental studies of molecular interactions and dissolution inhibition in poly(norbornene-alt-maleic anhydride)-based resins

The progress of developer base into films of terpolymers of norbornene-male ic anhydride and acrylic acid was shown to be a percolation process with a critical site concentration of x(C) = 0.084, implying that every acrylic ac id site in the terpolymer makes 12 monomer units of the polymer water compa tible. Using these terpolymers, the dissolution inhibition mechanism for tw o types of common additives, tert-butyl carboxylate (e.g., cholates, cycloh exanecarboxylates, and malonates) dissolution inhibititors and onium salt p hotoacid generators (PAG's), were examined. Additionally, the dissolution p romotion mechanism of carboxylic acids released from acidolysis of tert-but yl esters was investigated. For a wide range of cholates and other tert-but yl carboxylate derivatives, increasing hydrophobicity is a good predictor o f increased dissolution inhibition. The molar dissolution promotion ability of a carboxylic acid increases with increasing number of both carboxyl and hydroxyl ester functional groups. For onium salt PAG's, a decrease in diss olution inhibition occurred when increasing the hydrophobicity and size of counteranions. Rather than being tied to hydrophobicity, large changes of d issolution inhibition in this class of materials appear to correlate with t heir ability to interact with carboxyl groups.