FTIR laboratory: quickly identify a degraded polymer

A degraded polymer can become difficult to recognise visually: colour changes, embrittlement, loss of flexibility, cracking, abnormal odour or changes in thermal behaviour. For a plastics manufacturer, processor or user of polymer parts, the challenge is to quickly obtain a reliable answer about the nature of the material in order to secure sorting, incoming inspection, quality investigation or an initial failure assessment. The FTIR laboratory approach enables rapid identification of the polymer family, even in a context of ageing or partial degradation.

In industry, a degraded polymer material can lead to dimensional non-conformities, reduced mechanical performance, appearance defects, premature failures, or processing difficulties. The need is not always to carry out a full de-formulation immediately: often, the first step is to quickly determine which material is involved and whether its degradation has altered its analytical signature. This answer is useful for comparing a batch, checking a supplier substitution, guiding material sorting, or ruling on a production anomaly.

The analytical foundation relies on IRTF, which makes it possible to acquire the infrared spectrum and compare it with an internal library in order to identify the polymer family. This approach is particularly well suited to rapid exploratory requests when the client wants to know whether it is a PE, a PP, a PVC, a PU, or another common polymer. TGA completes this reading by recording mass loss during a temperature ramp that can reach 800°C, making it possible to determine the decomposition profile, degradation temperature, and mass fraction of mineral fillers if present.

The laboratory supports industrial companies that need a clear, fast, and actionable answer about the nature of an altered polymer material. The goal is not only to produce an analytical result, but also to help make a decision: validate a material, investigate a failure, compare two samples, guide sorting, or prepare a more in-depth study. This approach is particularly useful in cases of non-conformity, aging, dual sourcing, or supplier changes.

Identifying a degraded material relies on combining several analytical readings. FTIR makes it possible to acquire the sample’s spectral fingerprint and compare it with an internal library to quickly point toward a family such as PE, PP, PVC, PU, or other organic matrices. In addition, thermal analysis by TGA clarifies the decomposition profile, degradation temperature, and any presence of mineral fillers. Depending on the need, the investigation can be taken further by GC/MS pyrolysis, organic additive screening, morphological observation, or residue characterization. To learn more about thermal decomposition, see our page Analysis Of Polymers By Tga In The Laboratory.

Signs of degradation may be thermal, chemical, or morphological: yellowing, oxidation, mass loss on heating, changes in spectral bands, appearance of mineral residues, or changes in chain structure. A suitable polymer analysis makes it possible to distinguish a simple material variation from more advanced aging. If additional characterization of fillers or morphology is needed, observation in a MEB analysis laboratory can complement the interpretation.

When the material is heavily altered or when its structure needs to be understood in greater detail, the laboratory can use GC/MS pyrolysis to identify the polymer, confirm a copolymeric nature, and qualitatively screen for monomers, oligomers, residual solvents, or certain semi-volatile additives. Other methods may be used depending on the objective: organic additive screening, trace analysis, chain-end determination, or rheological study. For volatile or semi-volatile compounds, a complementary Headspace GC MS laboratory analysis approach may be relevant.

The added value lies in the complementarity of the techniques available: IRTF, TGA, GC/MS pyrolysis, filler observation, and advanced structural analysis. This analytical continuity avoids multiplying contacts and makes it possible to adapt the depth of investigation to the actual need. Depending on the case, additional fine-structure or morphology examinations may be considered via Met analysis laboratory or dedicated tests in Polymer Rheological Analysis Laboratory.

To get started, simply provide a few key details: the type of part or product, the observed degradation context, the material reference if known, the expected objective, and any comparison with a sound control sample. The laboratory can then guide you toward a rapid identification strategy or a more in-depth characterization. To move forward efficiently: describe the observed defect, submit the relevant samples, compare with a reference if possible, request technical advice on the appropriate level of investigation, schedule the analysis according to industrial urgency.