Various cycloolefinic/maleic anhydride/maleimide polymers and compositions thereof useful for forming self-imageable films encompassing such polymers are disclosed. Such polymers encompass norbornene-type repeating units, maleimide repeat units and maleic anhydride-type repeating units where at least some of such maleic anhydride-type repeating units have been ring-opened. The films formed from such polymer compositions provide self imageable, low-k, thermally stable layers for use in microelectronic and optoelectronic devices.