Conformation of adsorbed random copolymers: A solid-state NMR and FTIR-PASstudy

The properties of bulk and adsorbed polyethylene-co-acrylic acid (PEA) rand om copolymers were characterized by solid-state NMR and vibrational spectro scopy. FTIR-PAS (Fourier transform infrared photoacoustic spectroscopy) mea surements show that the copolymers are chemisorbed to zirconia surfaces via the carboxylic acid sticker groups. The chain mobility, conformation, and morphology of bulk and adsorbed PEA were studied by C-13 CP-MAS, 2D WISE, a nd H-1 spin diffusion NMR experiments. The effect of the copolymer loading and acrylic acid content on these properties was examined. Whereas adsorbed PEA with a 5% w/w acrylic acid content contain transoid chain segments at all loadings, samples with higher acrylic acid contents (15 % w/w) only dis play an all-trans component at higher loadings where unbound acid groups ar e present.