• Top library match: Poly(vinyl alcohol) #30928

• The nearest library hit has zero reported similarity and therefore does not provide strong match confidence.
• A simple assignment to Poly(vinyl alcohol) is limited by the strong 1723 cm-1 carbonyl band, which suggests additional chemistry not required for that polymer.
• The Top-15 library candidates are chemically diverse, including chlorinated, acidic, acetal, sulfonated, and other polymer types, S-O the retrieval does not converge on one specific structure.
• No direct reference match or related literature match was recovered to narrow the assignment.
• The current spectrum cannot distinguish whether the carbonyl arises from an ester-containing polymer, partially oxidized/polymer-blended material, plasticizer, or surface coating component.
• The available evidence does not securely establish whether the sample is a single polymer, a copolymer, or a formulated mixture.
• Bands below 1000 cm-1 are not sufficiently characteristic here to confirm halogenation, aromatic substitution pattern, or a specific repeat unit.

Recommended next steps: Compare the sample specifically against authenticated FTIR references for Poly(vinyl alcohol), poly(vinyl butyral), poly(acrylic acid), and ester-containing oxygenated polymers, focusing on the 1723 cm-1 carbonyl intensity and the 1000-1300 cm-1 C-O pattern. If the sample is a coating, adhesive, or formulated film, examine extraction or separation of additives/plasticizers before repeat FTIR measurement to determine whether the carbonyl band comes from a secondary component. Acquire complementary data such as Raman spectroscopy, DSC, or pyrolysis-GC/MS to determine whether the material is a single oxygenated polymer or a blend. If practical, collect ATR-FTIR from multiple spots and, if possible, a transmission spectrum from a thin section to test whether the carbonyl-containing component is concentrated at the surface.