Photoacoustic procedure for measuring thermal parameters of transparent solids

Abstract

An application of photoacoustic technique is developed for determining the thermal diffusivity coefficient and the thermal conductivity of transparent materials. The backing material which supports the sample is made optically opaque, i.e., it entirely absorbs the incident light, and the converted heat diffuses through the sample heating the gas in contact with its opposite surface. The method is illustrated by fitting voltage amplitude and phase signals versus the chopping frequency in the photoacoustic cell, according to a theoretical model of heat diffusion. Thermal parameters obtained for three polymers compare very well with results from the literature.

Photopyroelectric spectroscopy of polyaniline films

“…Among the PTS techniques the photoacoustic spectroscopy (PAS), which is the most traditional one, and the recent photopyroelectric spectroscopy (PPES) have been used for studying thermal and optical properties of polymeric films. 6,7 This article presents a PPES study of polyaniline films, with different doping degree, whose objective is to obtain their thermal conductivity and thermal diffusivity coefficients. Polyaniline and its derivatives are considered promising conducting polymers for several applications 8,9 because they present good doping characteristics, high environmental stability, and easily solubility and processability.…”

Study of the degree of photoactivation of the Z250 resin by photoacoustics

“…In 1976, Rosencwaig and Gersho published a theoretical model for the photoacoustic signal in solid samples -the Rosencwaig-Gersho Model 1 . Since then, the photoacoustic technique has been employed in different biological and biomedical sciences [2][3][4][5][6][7][8][9] . Until now, there have been few works using the photoacoustic technique to monitor resin polymerization.…”

Генерация Фотоакустического Сигнала Двухслойными Прозрачными Образцами С Поглощающей Подложкой

“…Однако в [13], как и в [14], рассматривался случай, когда подложка является прозрачной. В [15] предложена теория генерации ФА-сигнала для однослойных прозрачных систем, находящихся на поглощающей подложке. Целю настоящей работы является построение теории генерации ФА-сигнала прозрачными двухслойными системами, находящимися на поглощающей подложке.…”