Related Experiment Video
Updated: Aug 15, 2026

Submillisecond Conformational Changes in Proteins Resolved by Photothermal Beam Deflection
Published on: February 18, 2014
[The effect of temperature on the structure and properties of polyurethane-urea by FTIR]
1State Key Laboratory of Heavy Oil Processing, University of Petroleum, 102200 Beijing.
Abstract:
The effect of temperature on the structure and properties of polyurethane-urea was investigated by in situ FTIR. Data from FTIR spectra showed that with increasing temperature the nu NHHbonded areas decrease and the nu NHfree band areas increase. The band site of nu NHHbonded shifted to higher wavenumbers and the band site of nu NHfree keeps constant. The band site of Cfree urethane shift from 1,731 cm-1 to 1,736 cm-1. All kinds of carbonly bands sites shifted to high wavenumbers. But the band sites of amide II and the C=C in aromatic ring shifted to low wavenumbers. The properties of PUU polymers was determined by the structure of soft domains.
Related Concept Videos
IR Spectrum Peak Splitting: Symmetric vs Asymmetric Vibrations
IR and UV–Vis Spectroscopy of Aldehydes and Ketones
¹H NMR of Conformationally Flexible Molecules: Variable-Temperature NMR
IR Absorption Frequency: Delocalization
In IR spectroscopy,...
IR Frequency Region: Alkyne and Nitrile Stretching
Comparing the stretching vibrational frequency of C≡C triple bonds with that of double and single bonds, it is evident that C≡C triple bonds exhibit a higher stretching frequency than C=C double and C–C single bonds. Similarly, the C≡N triple bond exhibits higher stretching absorption than the C=N...
Atomic Spectroscopy: Effects of Temperature
At thermal equilibrium, the relative populations of excited and ground state atoms can be estimated using the Maxwell–Boltzmann distribution. For example, an increase in temperature from...

