A　series　of　polymers　derived　from　poly(isobutylene-alt-maleic　anhydride)　(PIMA)　with　ca.　1%　to　＞90%　of　the　anhydride　units　randomly　substituted　with　1-pyrenylmethylimido　groups　(Py-PIMA)　has　been　synthesized　and　characterized.　The　remaining　anhydride　units　in　the　Py-PIMA　with　10%　pyrenyl　substitution　have　been　converted　to　N-hexyl　and　N-decyl　imides.　The　photophysical　properties　of　these　polymers,　as　obtained　from　steady-state　fluorescence　intensities,　time-correlated　single　photon　counting　experiments,　and　time-resolved　emission　spectra,　have　provided　insights　into　the　dependence　of　the　polymer　conformations　and　their　labilities　on　the　degree　of　pyrenyl　substitution,　the　nature　of　the　appended　alkyl　chains,　temperature,　and　solvent　properties　according　to　the　Flory　interaction　coefficient　and　Hansen　solubility　parameters.　None　of　the　solvent　characteristics,　alone,　can　account　for　all　aspects　of　the　polymer　behavior.　The　interactions　of　the　medium　with　the　polymer　chains　and　the　excited　singlet　states　of　the　pyrenyl　units　must　be　considered　somewhat　differently.　The　results　also　indicate　that　PIMA　is　a　potentially　very　useful　and　versatile　platform　for　other　investigations　of　polymer　chain　and　probe　dynamics.　©　2017　American　Chemical　Society.