Abstract
The synthesis of well-defined second-generation PS(n)PtBA(2n) dendrimer-like copolymers based on polystyrene (PS) and poly(tert-butylacrylate) (PtBA) is described. The synthetic procedure involves a combination of atom transfer radical polymerization (ATRP) using multifunctional initiators and chain end modification reactions. These structures are composed of a PS core with 2, 4, 6, or 8 arms and a corona of PtBA with 4, 8, 12, or 16 arms, respectively. Third-generation PS(n)PS(2n)PtBA(4n) dendrimer-like copolymers were also derived by repetition of chain end modification and ATRP. Characterization was carried out by size exclusion chromatography online with multiangle laser light scattering and by H-1 NMR spectroscopy. PS(n)PAA(2n) amphiphilic structures based on PS and poly(acrylic acid) (PAA) were subsequently generated by hydrolysis of the tert-butylester groups. Langmuir monolayer studies of PS(n)PtBA(2n) showed the formation of stable films. AFM images demonstrated a significant change in morphology upon increasing surface pressures.