What absorbs at 3030 cm⁻¹ in an FTIR spectrum?

Quick answer

A band near 3030 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 3030 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

• Alkene (C=C) confidence 1.0

  “The 3030cm-1 (=C-H methylene protons at 5H of the 3-Octanoylthio-1-propyltriethoxysilane peak at stretching vibration) remains same after 2856cm-1 modification.”

  Reactive grafting of 3-octanoylthio-1-propyltriethoxysilane in styrene butadiene rubber_ Characterization and its effect on silica reinforced tire composites DOI: 10.1016/j.polymer.2019.121693
• N h confidence 1.0

  “The band at 3030 should be assigned to the band of 1 3+ beenpressedfrompowderimmediatelyafterdryingfromsolution the side chain NH groups.”

  Rozenberg 和 Shoham - 2007 - FTIR spectra of solid poly-L-lysine in the stretch DOI: 10.1016/j.bpc.2006.07.008
• Hydroxyl (O-H) confidence 1.0

  “The cm-1 The band shifting of the O-H groups in extract and nanoparticles around 3030 cm-1 conband shifting of the O-H groups in extract and nanoparticles around 3030 constituted”

  Spectroscopic and Antibacterial Properties of CuONPs from Orange, Lemon and Tangerine Peel Extracts: Potential for Combating Bacterial Resistance DOI: 10.3390/molecules26030586
• Alkyl C-H confidence 1.0

  “low-temperature retorting In this routine method, cm-1(stretching the -CH groups), 2960 vibration of C-H in 2 the oil shale sample is heated to 500 °C in the absence of air, cm-1(stretching the -CH groups) and 3030 vibration of CH in 3 and”

  Zhao 等 - 2015 - Evaluation of Oil Yield of Oil Shale by Infrared S DOI: 10.1007/s40242-015-4364-3
• Alkyl C-H confidence 1.0

  “Both spectra, also show an cm-1, which comes from the C-H stretching vibration on absorption peak around 3030 position 3 and 4 of the thiophene ring.”

  Dams 等 - 2006 - Plasma deposition of thiophene derivatives under a DOI: 10.1002/cvde.200606483
• Alkyl C-H confidence 1.0

  “cm-1 with strong absorptions at 701 and 744 Additional peaks are observed at 3030 (C-H cm-1 stretching), 1454 and 1495 (aromatic ring breathing).”

  Germinario 等 - 2016 - Chemical characterisation of spray paints by a mul DOI: 10.1016/j.microc.2015.04.016
• Alkyl C-H confidence 1.0

  “The spectrum shows 3030 cm-1, 2963 cm-1, 2925 cm-1, and 2855 cm-1 lines interpreted as stretch C-H vibrations in =CH-, -CH2-”

  Bound (“Glassy”) Rubber as a Free Radical Cross-linked Rubber Layer on a Carbon Black DOI: 10.3390/ma11101992
• Acetate confidence 1.0

  “A library search result also produced the best match with ester epoxy resins having ATRcm-1 υ(C-H), υ(C-O), δ(C-O-O) having ATR-FTIR peaks at 3030, 912, and 826 due to the and bands, FTIR peaks at 3030, 912, and 826 cm-1 due to the υ(C-H),”

  Multi-Modal Compositional Analysis of Layered Paint Chips of Automobiles by the Combined Application of ATR-FTIR Imaging, Raman Microspectrometry, and SEM/EDX DOI: 10.3390/molecules24071381