[摘要]：Thermal transitions in the 20 : 5 polydimethylsiloxane (PDMS)-polyphenylsilsesquioxane block copolymer (BCP) and in PDMS subjected to gamma-irradiation at doses to 100 kGy have been studied. It has been found that the release of a PDMS phase did not occur in the initial and irradiated BCPs. The irradiation of BCP with small doses leads to the formation of a significant amount of a gel fraction (to 25%) as a result of the grafting of cyclodimethylsiloxane (D-x) impurities to the PDMS block of the copolymer. This conclusion is supported by the results of thermal analysis and IR-spectroscopic data.
