Synthesis and Investigation of Surface Properties of Dendrimer-like Copolymers Based on Polystyrene and Poly(<i>tert</i>-butylacrylate)

Abstract

The synthesis of well-defined second-generation PSnPtBA2n 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 PSnPS2nPtBA4n 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 1H NMR spectroscopy. PSnPAA2n amphiphilic structures based on PS and poly(acrylic acid) (PAA) were subsequently generated by hydrolysis of the tert-butylester groups. Langmuir monolayer studies of PSnPtBA2n showed the formation of stable films. AFM images demonstrated a significant change in morphology upon increasing surface pressures.