Luminescent solar concentrators based on molecular dyes are a promising approach to light collection for photovoltaics owing to their potential low cost and wide light acceptance angles. However, they readily suffer from self-absorption, which rapidly reduces device efficiency. We use a perylene-based sensitizer-emitter system to reduce self-absorption. The sensitizer and emitter are copolymerized to enhance energy transfer to the emitter. The sensitizer is susceptible to yield-reducing H-aggregation. We show that a composite polymer can be used to reduce H-aggregation, while maintaining efficient energy transfer.