A　new,　structurally　random　perylene　diimide　(PDI)　copolymer　acceptor,　PPDI,　has　been　readily　synthesized　from　Stille　cross-coupling　polycondensation　of　two　pairs　of　regioisomeric　dibromo-PDIs　with　2,5-bis(trimethylstannyl)thiophene.　PPDI　possesses　a　complex　structural　configuration　with　a　greatly　twisted　conformation,　and　thus　exhibits　weak　intermolecular　interactions.　A　solution　of　PPDI　and　a　polymer　donor　such　as　PBT7-Th　affords　a　smooth　homogenous　film　without　large　crystalline　domain　formation.　This　composite　film　absorbs　strongly　throughout　the　visible　spectrum,　and　when　used　as　an　active　layer　in　all-polymer　solar　cells,　provides　a　power　conversion　efficiency　of　over　5%.　©　2017　Elsevier　Ltd