What absorbs at 2887 cm⁻¹ in an FTIR spectrum?

Quick answer

A band near 2887 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.

Возможные назначения функциональных групп

Ранжирование отражает накопленные литературные данные, а не единственное авторитетное правило. Всегда проверяйте в контексте вашего образца.

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 2887 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.

Литература, лежащая в основе этих назначений

• Alkyl C-H достоверность 1,0

  “cm´1, for the OH group of pure PHB appears between 3200 and 4000 but the broad band of the OH The stretching peaks at 1452, 1379, 1223, and 2887 cm-1 correspond to the methyl group.”

  Influence of Electrospinning Parameters on Fiber Diameter and Mechanical Properties of Poly(3-Hydroxybutyrate) (PHB) and Polyanilines (PANI) Blends DOI: 10.3390/polym8030097
• Carbohydrate достоверность 1,0

  “4000 3500 3000 2500 2000 1500 1000 stronger hydrogen bonding could be concluded from the double (cm-1) Wave Number 2919cm-1 2887cm-1 999cm-1 992cm-1 peaks at to and to in nanocomposites samples when compared with pure starch (Ding, Ainswort”

  Glycerol/starch/Na+-montmorillonite nanocomposites: A XRD, FTIR, DSC and 1H NMR study DOI: 10.1016/j.carbpol.2010.10.018
• Alkyl C-H достоверность 1,0

  “Instead, the large cm-1 vibration band located at 2887 and corresponding to the C-H stretching from the aliphatic chain showed a decrease in intensity during laser irradiation.”

  Spectroscopic Characterization of Emulsions Generated with a New Laser-Assisted Device DOI: 10.3390/molecules25071729
• Hydroxyl (O-H) достоверность 1,0

  “The H-O-H stretching vibrations of a collection of water molecules engaged in crystallization are restretching vibrations of a collection of water molecules engaged in crystallization are stretching vibrations of a collection of water molec”

  Synthesis and Characterization of New Composite Materials Based on Magnesium Phosphate Cement for Fluoride Retention DOI: 10.3390/ma16020718
• Alkyl C-H достоверность 0,8

  “Intense spectra in group 2887-2925 attributed to CH2/CH3.”

  Potato Starch Utilization in Ecological Loose-Fill Packaging Materials—Sustainability and Characterization DOI: 10.3390/ma13061390
• Alkyl C-H достоверность 0,7

  “Context: C-H stretching at three frequencies.”

  Alghamdi 等 - 2021 - Effects of various media on micellization, adsorpt DOI: 10.1098/rsos.211527