The reaction of Poly (vinyl chloride) (PVC) with different alcohols (L) in Tetrahydrofuran (THF) forms the PVC-L compounds. The resulted compounds have been characterized by spectroscopic methods. The structures of these complexes were studied by FTIR and UV-VIS spectrophotometry. The optical properties in the region from (200-900 nm) were recorded using UV-VIS spectrophotometer. The optical data analyzed and interpreted in term of the theory of phonon assisted direct electronic transitions. The measured values of energy gap (Eg) for pure and modified PVC get favor the following order: PVC >PVC-LI> PVC-LII >PVC-LIII >PVC-LIV> PVC-LV PVC-LVI >PVC-LVII