Asymmetric block copolymers PAAc-b-PAAm (DBCs) and PAAm-b-PAAc-b-PAAm (TBCs) comprised poly(acrylic acid) blocks of constant chain length and polyacrylamide blocks of variable chain length were synthesized using RAFT/MADIX technique. Their properties in a bulk state were studied by differential scanning calorimetry and the hydrogen bond system was investigated by Fourier transform infrared spectroscopy. It was found that DBCs and TBCs possess a homogeneous amorphous structure, whose temperatures of glass transition and destruction beginning increased with growth of PAAm block length. The H-bond system between PAAc and PAAm blocks was most developed in TBC sample and formed manly by the mixed cyclic dimmers of carboxyl and amide groups.