Why polystyrene is used in IR calibration?
Instrument manufacturers supply polystyrene films for routine checks of their spectrometers. The films have a matte finish that reduces the amplitude of interference fringes but also increases scattering. They vary significantly in thickness, scattering properties, and even chemical composition.
What does infrared spectroscopy detect?
It is used by chemists to determine functional groups in molecules. IR Spectroscopy measures the vibrations of atoms, and based on this it is possible to determine the functional groups. 5 Generally, stronger bonds and light atoms will vibrate at a high stretching frequency (wavenumber).
Which of the following polymer is used in the infrared spectroscopy?
The IR spectra of a number of standard polymers, such as polytetrafluoroethylene (PTFE), polystyrene (PS), polypropylene (PP), and polyethylene (PE), are shown in Figure 1. The PerkinElmer Spectrum Two FT-IR equipped with UATR sampling accessory is used to determine the IR spectra (Figure 2).
How does an infrared spectroscopy work?
Infrared (IR) spectroscopy uses infrared radiation to excite the molecules of a compound and generates an infrared spectrum of the energy absorbed by a molecule as a function of the frequency or wavelength of light. Different types of bonds respond to the IR radiation differently.
What is the principle of infrared spectroscopy?
IR spectroscopy detects the absorption of light by a compound, in the IR region of the electromagnetic spectrum. To absorb light a molecule must have a bond within its structure that can exhibit what is referred to as a ‘dipole moment’ which means electrons within a bond are not shared equally.
How does the infrared spectrometer work?
An infrared spectrometer analyses a compound by passing infrared radiation, over a range of different frequencies, through a sample and measuring the absorptions made by each type of bond in the compound. This produces a spectrum, normally a ‘plot’ of % transmittance against wavenumber.
What type of material is polystyrene?
polystyrene, a hard, stiff, brilliantly transparent synthetic resin produced by the polymerization of styrene. It is widely employed in the food-service industry as rigid trays and containers, disposable eating utensils, and foamed cups, plates, and bowls.
How is infrared spectroscopy used in polymer analysis?
Infrared (IR) spectroscopy is ideally suited to qualitative analysis of polymer starting materials and finished products as well as to quantification of components in polymer mixtures and to analysis of in-process samples. IR spectroscopy is reliable, fast and cost-effective.
How is the use of IR spectroscopy used?
IR spectroscopy is reliable, fast and cost-effective. This application note describes several approaches to the measurement and analysis of IR spectra of typical polymer samples, and applies the techniques to the identification of some industrial polymer samples.
What are the uses of mid infrared spectroscopy?
Polymer Identification using Mid Infrared Spectroscopy Introduction Synthetic polymers are very widely used today, with diverse applications in various industries such as food, automotive, and packaging.
Why are there different spectra for different materials?
The clear differences between the spectra allow a ready discrimination between the materials by visual inspection. Additional interpretation of the spectra can yield information about the structure: for example, looking at the C–H stretch region around 2950 cm-1, differences can be seen between PE and PP due to the differing ratios of CH