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An X-ray Diffraction Study of γ-Irradiated Siloxane Block Copolymers

“…It was noted that siloxane diblock copolymers differed from multiblock copolymers in many characteristics, for example, supramolecular structure. The multiblock copolymers were distributed as densely arranged globules, whereas the diblock copolymers were structureless matrices [3,4]. Globular formations were observed in the diblock copolymers after irradiation to a dose higher than the dose of gelation.…”

“…According to data obtained by differential scanning calorimetry (DSC), peaks due to cold crystallization ( T = -80° C) and melting ( T ~ − 50° C) were observed in the initial diblock copolymers, as distinct from the multiblock copolymers. Note that, after the irradiation of siloxane diblock copolymers to a dose higher than 100 kGy, which corresponds to the dose of 1 e-mail: pankratova@rc.chem.msu.ru the onset of gelation, two melting peaks appeared in the DSC curve at the temperatures T m1 = -52 ° C and T m2 = +20 ° C. As the dose was increased to 400 kGy, the crystallization temperature T c increased to -35° C, and the melting temperature T m1 increased to +27 ° C; the second melting peak was not observed at radiation doses higher than 100 kGy [4,5]. In [4,5], we first noted the difference between diblock and multiblock copolymers.…”