Vibrational Spectroscopy (Allentown Lab)

FTIR, Raman and Near-infrared spectroscopy for the characterization of polymers and chemical systems

Vibrational spectroscopy is a non-destructive identification method that measures the vibrational energy in a compound using various types of spectroscopy analysis.

Intertek Allentown has over 30 years of experience using Fourier Transform Infrared (FTIR), Raman and Near-infrared spectroscopy for the characterization of polymers and chemical systems. This expertise enables the identification of polymers and polymer additives, unknown surface contamination and defects, and characterization of thermoset polymer cure chemistry. Microscopy capabilities are used to identify particulates, fibers, and defects in materials, and when paired with other available techniques, complex systems can be characterized.

Infrared analysis of unknown materials is supported by an extensive collection of commercial and in-house spectrum libraries.

Intertek Allentown’s scientific team provides total quality assurance expertise for your vibrational spectroscopy needs.

FTIR is an analytical technique that uses infrared light to observe properties of a solid, liquid or gas. It produces a spectrum of characteristic bands that help identify and characterize the sample.

- Surface characterization for coatings and contamination with a variety of sampling methods:
- - Attenuated Total Reflection (ATR): direct contact method that obtains spectra of surfaces and surface residues.
- - Photo Acoustic Spectroscopy (PAS): non-contact method that, in combination with phase-modulated infrared spectroscopy, can characterize surface and sub-surface materials.
- - Infrared Reflection-Absorption Spectroscopy (IRRAS): non-contact method used to identify thin coatings or contamination on metal surfaces.
- Particulates and fibers analyzed by infrared microscopy with a variety of methods:
- - Diamond compression cell used to press samples to an appropriate thickness to obtain transmission spectra.
- - Micro-ATR objective used to obtain spectra of small areas on a sample surface.
- - Reflectance spectra obtained from material captured on a silver filter.
- Identification of gas-phase thermal decomposition or oxidation products made possible through combination with thermogravimetric analysis (TGA) instrumentation.
- Analysis of GPC effluents using a fraction collector in combination with a high-sensitivity ATR system.

Near-infrared spectroscopy (NIRS) is a method that uses the near-infrared region of the electromagnetic spectrum based on overtones and combinations of bond vibrations in molecules.

- Process analytical feasibility using fiber optic probes (suitable for either clear liquids or solids/slurries).
- Characterize reaction kinetics for isothermal epoxy thermoset curing.

Raman spectroscopy is a technique used to observe vibrational, rotational, and other low-frequency modes in a system to help identify molecules.

- Particle and fiber analysis using a confocal Raman microscope.
- Composition and thickness of individual layers in laminated packaging film cross-sections measured using a confocal Raman microscope with a mapping (XYZ) stage.
- Surface corrosion and contamination characterized with a confocal Raman microscope.
- FT-Raman spectroscopy used to obtain spectra of bulk materials and materials that present problems with fluorescence.