Why is polystyrene film used in IR calibration?

Polystyrene films have long been used for checking the general performance of infrared (IR) spectrometers and specific tests for wavenumber accuracy and resolution based on such films are enshrined in various pharmacopoeias (1–4).

Which is the important IR peaks for polystyrene?

Bands of the IR spectrum for polystyrene correspond to their functional groups, C-H aromatic tension 3081,2 cm-1 – 3001,11 cm-1; 2923,91 cm-1 and 2850,40 cm-1 CH2 asymmetric and symmetric tension; 1943,19 –1728,23 cm-1 aromatic ring monosubstitution; 1452,28 cm-1 deformation CH2 + C=C of the aromatic ring; 1069,65 cm-1 …

Why KBr is used in IR spectroscopy?

Potassium bromide (KBr, spectroscopic grade) is typically used as the window material because it is transparent in the IR, between 4000–400 cm-1. Alternatively, samples can be contained within a KBr matrix and pressed to form a pellet that is then analysed.

What is the thickness of polystyrene film?

Pair of polystyrene calibration films of different thickness. One film is 38 microns and is provided with certification of traceability to five (5) NIST 1921b frequencies. The second film is 76 microns and is provided without certification.

What is polystyrene film used for?

Polystyrene films are used for a variety of packaging, laminating, and printing applications. Some grades are also approved for direct food contact.

Why is polystyrene used as a sample in FTIR?

Polystyrene and L ow density polyethylene was used as the sample during the analysis. Vis) used as sources. It is capable of measuring transmission, reflectance and absorption in solid or liquid state materials [6 ]. It has an enough energy to excite electrons for anti-bonding.

What are the UV absorption values of polystyrene?

Diagram 1: UV-Vis result for Polystyrene sample. Diagram 1 shows the UV-visible absorption spectrum for polystyrene. Absorbance on the vertical axis is the measure of the amount of li ght absorbed. The higher the value, the mor e of a particular wavelength is being absorbed. The absorption peaks at a value of 238 nm.

How to calculate the spectra of caffeine ATR?

View entire compound with free spectra: 14 NMR, 8 FTIR, 2 Raman, and 52 MS SpectraBase Compound ID 5mzfOFTj9A9 InChI InChI=1S/C8H10N4O2/c1-10-4-9-6-5 (10)7 ( InChIKey RYYVLZVUVIJVGH-UHFFFAOYSA-N Google Searc Mol Weight 194.19 g/mol Molecular Formula C8H10N4O2

What is the absorption band of polystyrene ( PST )?

Polystyrene (PSt) exhibits a new UV absorption band at around 290nm in comparison with ethylbenzene, which is attributed to associative interaction between pendant phenyl groups. Similar absorption bands are also observed for polymers of styrene derivatives.