What absorbs at 3632 cm⁻¹ in an FTIR spectrum?

Quick answer

A band near 3632 cm⁻¹ is usually interpreted by checking which functional groups repeatedly co-occur there in the literature, then confirming at least one or two additional peaks in the same sample. This page ranks those assignments by accumulated evidence rather than by a single fixed textbook rule.

Possible functional-group assignments

Ranking reflects accumulated literature evidence, not a single fixed rule. Always confirm against your sample context.

Possible materials

Materials are shown only when the same literature pool supports this band and at least one additional characteristic peak.

Spectrum logic

This band becomes meaningful only when read with its neighboring peaks. In practice, analysts first look at the assignments above, then check whether the same sample also shows other peaks expected for the same structural motif. A lone band near 3632 cm⁻¹ is usually not enough for material identification by itself.

Real-world usage

This type of query is common in polymer identification, unknown plastic screening, QC troubleshooting, recycled-material verification, and literature-backed peak assignment review.

Common mistakes

• Treating one isolated band as proof of a material without checking at least one or two supporting peaks.
• Ignoring overlap: multiple functional groups can contribute near the same wavenumber.
• Skipping validation when additives, blends, oxidation, or contamination may distort the spectrum.

Verification advice

When ambiguity remains, validate the hypothesis with DSC, GC-MS, or TGA, especially for blends, degraded samples, and filled polymers.

Literature behind these assignments

• Hydroxyl (O-H)

  Reported band

  3632 cm-1

  Assignment

  Hydroxyl (O-H)

  Material / context

  chitosan; polyvinyl alcohol; PVA/CH/AgNPs hydrogel

  Sprayed in-situ synthesis of polyvinyl alcohol/chitosan loaded silver nanocomposite hydrogel for improved antibacterial effects DOI: 10.1016/j.ijbiomac.2019.09.186
• Hydroxyl (O-H)

  Reported band

  3632 cm-1

  Assignment

  Hydroxyl (O-H)

  Material / context

  PP-R micro-specimen

  Temperature dependent degradation of phenolic stabilizers and ageing behaviour of PP-R micro-specimen DOI: 10.1016/j.polymdegradstab.2023.110311
• Hydroxyl (O-H)

  Reported band

  3632 cm-1

  Assignment

  Hydroxyl (O-H)

  Material / context

  sodium bentonite; organobentonite

  Metabolic and molecular methods to evaluate the organoclay effects on a bacterial community DOI: 10.1016/j.envpol.2013.04.012
• Water (H2O)

  Reported band

  3632 cm-1

  Assignment

  Water (H2O)

  Material / context

  —

  Iwata 等 - 2009 - Identification of FTIR Bands Due to Internal Water DOI: 10.1021/bi801990s
• Hydroxyl (O-H)

  Reported band

  3632 cm-1

  Assignment

  Hydroxyl (O-H)

  Material / context

  TiO2; Pt-TiO sample; Pt-loaded TiO2 P25

  Interfacial charge transfer in Pt-loaded TiO2 P25 photocatalysts studied by in-situ diffuse reflectance FTIR spectroscopy of adsorbed CO DOI: 10.1016/j.jphotochem.2018.10.023
• Hydroxyl (O-H)

  Reported band

  3632 cm-1

  Assignment

  Hydroxyl (O-H)

  Material / context

  sub>(P25) to Nanoanatase; nanoanatase; pyrogenic TiO2 (P25)

  Particles Morphology and Surface Properties As Investigated by HRTEM, FTIR, and Periodic DFT Calculations: From Pyrogenic TiO2(P25) to Nanoanatase DOI: 10.1021/jp303942h
• Hydroxyl (O-H)

  Reported band

  3632 cm-1

  Assignment

  Hydroxyl (O-H)

  Material / context

  rutile; water

  Rutile Surface Properties Beyond the Single Crystal Approach: New Insights from the Experimental Investigation of Different Polycrystalline Samples and Periodic DFT Calculations DOI: 10.1021/jp401916q