Chain‐Regulated Degradation of Polyvinyl Chloride in UiO‐Type Metal–Organic Frameworks

Converting polyvinyl chloride (PVC) into valuable hydrocarbons is hindered by rapid dehydrochlorination, which produces mainly coke and HCl and limits global recycling to below 8%. Existing strategies activate specific bonds but overlook chain regulation. Here we show that regulating PVC chains within the sub‐nanometer channels of UiO‐type metal–organic frameworks (MOFs) redirects degradation from uncontrolled elimination to size‐selective chain scission. In Zr‐based UiO‐66 and UiO‐67, periodic acidic Zr clusters anchor PVC through Zr─Cl bonds, inducing heterolytic C─Cl cleavage and β‐scission of carbocationic intermediates. The yield of volatile hydrocarbons increases from <5 wt% for bulk PVC degradation to ∼30 wt% for degradation in the MOF. The aliphatic chain length is governed by the MOF geometry‐dictated anchoring spacing ( γ ): UiO‐66 ( γ = 8 C─C bonds) favours C9 hydrocarbons, whereas UiO‐67 ( γ = 10) favours C11 hydrocarbons. Molecular dynamics, thermodynamic calculations, and statistical kinetic modelling reveal that γ and carbocation‐mediated scission events control the carbon number of the products. This work establishes chain regulation as a design principle for controlling polymer degradation.