A polymer of the formula: wherein M 1 is an optionally substituted perylene imide selected from: wherein: π-1 is a perylenyl group optionally substituted with 1-6 substituents independently selected from a) an electron-withdrawing group and b) a C 1-40 alkyl group optionally substituted with 1-5 electron-withdrawing groups; π-1' is a perylenyl group optionally substituted with 1-8 substituents independently selected from a) an electron-withdrawing group and b) a C 1-40 alkyl group optionally substituted with 1-5 electron-withdrawing groups; R 1, R 2, and R 5, independently are selected from H, a C 1-40 alkyl group, a C 2-40 alkenyl group, a C 1-40 haloalkyl group, and 1-4 cyclic moieties, wherein: each of the C 1-40 alkyl group, the C 2-40 alkenyl group, and the C 1-40 haloalkyl group can be optionally substituted with 1-10 substituents independently selected from a halogen, -CN, NO 2, OH, -NH 2, -NH(C 1-20 alkyl), -N(C 1-20 alkyl) 2, -S 2 OH, -CHO, -C -C 1-20 alkyl, -C OH, -C -OC 1-20 alkyl, -C NH 2, -C NH-C 1-20 alkyl, -C N(C 1-20 alkyl) 2, -OC 1-20 alkyl, -SiH 3, -SiH(C 1-20 alkyl) 2, -SiH 2 (C 1-20 alkyl), and -Si(C 1-20 alkyl) 3; each of the C 1-40 alkyl group, the C 2-40 alkenyl group, and the C 1-40 haloalkyl group can be covalently bonded to the imide nitrogen atom via an optional linker; and each of the 1-4 cyclic moieties can be the same or different, can be covalently bonded to each other or the imide nitrogen via an optional linker, and can be optionally substituted with 1-5 substituents independently selected from a halogen, oxo, -CN, NO 2, OH, =C 2, -NH 2, -NH(C 1-20 alkyl), -N(C 1-20 alkyl) 2, -S 2 OH, -CHO, -C OH, -C -C 1-20 alkyl, -C -OC 1-20 alkyl, -C NH 2, -C NH-C 1-20 alkyl, -C N(C 1-20 alkyl) 2, -SiH 3, -SiH(C 1-20 alkyl) 2, -SiH 2 (C 1-20 alkyl), -Si(C 1-20 alkyl) 3, -O-C 1-20 alkyl, -O-C 1-20 alkenyl, -O-C 1-20 haloalkyl, a C 1-20 alkyl group, a C 1-20 alkenyl group, and a C 1-20 haloalkyl group; M 2 is a repeating unit comprising one or more monocyclic moieties selected from: wherein: Ar, at each occurrence, is independently an optionally substituted monocyclic heteroaryl group, selected from the group consisting of a thienyl group, an isothiazolyl group, a thiazolyl group, a 1,2,4-thiadiazolyl group, a 1,3,4-thiadiazolyl group, and a 1,2,5-thiadiazolyl group, wherein each group optionally can be substituted with 1-2 substituents independently selected from a halogen, -CN, a C 1-6 alkyl group, a C 1-6 alkoxy group, and a C 1-6 haloalkyl group; π-2 is an optionally substituted polycyclic moiety; Z is a conjugated linear linker; and m, at each occurrence, is independently 1, 2, 3, 4, 5 or 6; and n is an integer greater than or equal to 2. π-1 is a perylenyl group optionally substituted with 1-6 substituents independently selected from a) an electron-withdrawing group and b) a C 1-40 alkyl group optionally substituted with 1-5 electron-withdrawing groups; π-1' is a perylenyl group optionally substituted with 1-8 substituents independently selected from a) an electron-withdrawing group and b) a C 1-40 alkyl group optionally substituted with 1-5 electron-withdrawing groups; R 1, R 2, and R 5, independently are selected from H, a C 1-40 alkyl group, a C 2-40 alkenyl group, a C 1-40 haloalkyl group, and 1-4 cyclic moieties, each of the C 1-40 alkyl group, the C 2-40 alkenyl group, and the C 1-40 haloalkyl group can be optionally substituted with 1-10 substituents independently selected from a halogen, -CN, NO 2, OH, -NH 2, -NH(C 1-20 alkyl), -N(C 1-20 alkyl) 2, -S 2 OH, -CHO, -C -C 1-20 alkyl, -C OH, -C -OC 1-20 alkyl, -C NH 2, -C NH-C 1-20 alkyl, -C N(C 1-20 alkyl) 2, -OC 1-20 alkyl, -SiH 3, -SiH(C 1-20 alkyl) 2, -SiH 2 (C 1-20 alkyl), and -Si(C 1-20 alkyl) 3; each of the C 1-40 alkyl group, the C 2-40 alkenyl group, and the C 1-40 haloalkyl group can be covalently bonded to the imide nitrogen atom via an optional linker; and each of the 1-4 cyclic moieties can be the same or different, can be covalently bonded to each other or the imide nitrogen via an optional linker, and can be optionally substituted with 1-5 substituents independently selected from a halogen, oxo, -CN, NO 2, OH, =C 2, -NH 2, -NH(C 1-20 alkyl), -N(C 1-20 alkyl) 2, -S 2 OH, -CHO, -C OH, -C -C 1-20 alkyl, -C -OC 1-20 alkyl, -C NH 2, -C NH-C 1-20 alkyl, -C N(C 1-20 alkyl) 2, -SiH 3, -SiH(C 1-20 alkyl) 2, -SiH 2 (C 1-20 alkyl), -Si(C 1-20 alkyl) 3, -O-C 1-20 alkyl, -O-C 1-20 alkenyl, -O-C 1-20 haloalkyl, a C 1-20 alkyl group, a C 1-20 alkenyl group, and a C 1-20 haloalkyl group; M 2 is a repeating unit comprising one or more monocyclic moieties selected from: Ar, at each occurrence, is independently an optionally substituted monocyclic heteroaryl group, selected from the group consisting of a thienyl group, an isothiazolyl group, a thiazolyl group, a 1,2,4-thiadiazolyl group, a 1,3,4-thiadiazolyl group, and a 1,2,5-thiadiazolyl group, wherein each group optionally can be substituted with 1-2 substituents independently selected from a halogen, -CN, a C 1-6 alkyl group, a C 1-6 alkoxy group, and a C 1-6 haloalkyl group; π-2 is an optionally substituted polycyclic moiety; Z is a conjugated linear linker; and m, at each occurrence, is independently 1, 2, 3, 4, 5 or 6; and n is an integer greater than or equal to 2.