An investigation of phenolic functional group accessibility in linear poly(4-hydroxy styrene) (PHS) and novel, branched poly(4-hydroxystyrene) (PHS-B) is presented. The phase behavior and extent of hydrogen bonding in blends of PHS-B with complimentary Lewis base polymers are calculated from glass transition temperature (T-g) enhancements measured using differential scanning calorimetry (DSC) techniques. The fraction of PHS-B hydroxyls accessible for hydrogen bonding were compared to linear PHS chains and small molecular weight analogs to help establish a molecular architecture-functional group accessibility property relationship for use with dissolution inhibition in candidate microlithographic photoresist binders. Design approaches to macromolecular structure and architecture for tailored intermolecular interactions in phenolic systems are discussed with respect to the effects of local steric screening as well as an intriguing thermodynamic competition between inter- and intra-molecular hydrogen bonding via molecular mechanics modeling.