DTG2-PSQ exhibited a relatively low Φ of 2% as a film, but Φ was improved to 38% by copolymerization with trimethoxymethylsilane. DTG2 was also copolymerized with a trimethoxysilyl-substituted carbazole derivative (CzS) to provide polysilsesquioxanes with DTG and carbazole units, which showed efficient photo-energy transfer from carbazole to DTG in the films. Similar copolymerization of DTG2 with CzS in