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/npsi/ctrl?lang=en http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/ctrl?lang=fr Access and use of this website and the material on it are subject to the Terms and Conditions set forth at http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/jsp/nparc_cp.jsp?lang=en NRC Publications Archive Archives des publications du CNRCThis publication could be one of several versions: author's original, accepted manuscript or the publisher's version. / La version de cette publication peut être l'une des suivantes : la version prépublication de l'auteur, la version acceptée du manuscrit ou la version de l'éditeur.Applied Spectroscopy, 50, 8, pp. 970-976, 1996 Comparison of IR techniques for the characterization of construction cement minerals and hydrated products Delgado, A. H.; Paroli, R. M.; Beaudoin, J. J.http://www.nrc-cnrc.gc.ca/irc Com pa rison of I R t e c hnique s for t he c ha ra c t e riza t ion of c onst ruc t ion c e m e nt m ine ra ls a nd hydra t e d produc t s NRCC-39008Delgado, A.H.; Paroli, R.M.; Beaudoin, J.J. September 1996A version of this document is published in / Une version de ce document se trouve dans:Applied Spectroscopy, 50, (8), pp. 970-976, 1996 The material in this document is covered by the provisions of the Copyright Act, by Canadian laws, policies, regulations and international agreements. Such provisions serve to identify the information source and, in specific instances, to prohibit reproduction of materials without written permission. For more information visit http://laws.justice.gc.ca/en/showtdm/cs/C-42Les renseignements dans ce document sont protégés par la Loi sur le droit d'auteur, par les lois, les politiques et les règlements du Canada et des accords internationaux. Ces dispositions permettent d'identifier la source de l'information et, dans certains cas, d'interdire la copie de documents sans permission écrite. Pour obtenir de plus amples renseignements : http://lois.justice.gc.ca/fr/showtdm/cs/C-42 The influence of FT-IR sampling techniques on the characterization of cement system", was investigated. Three FT-IR techniques were used to study tricalcium silicate (C 3 S), hydrated C 3 S, calcium hydroxide, and calcium silicate hydrate (C-S-H). They include transmission spectroscopy (TS), photoacoustic spectroscopy (PAS), and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The TS technique (using KBr pellets) was the most labor-intensive but was found to give the simplest spectra with welldefined bands. The PAS technique was found to be the simplest technique but yielded bands at lower wavenumber than TS. DRIFTS was determined to be a good alternative for cement powders since it provided spectra similar to those for the TS technique. DRIFTS required more sample preparation than PAS but less sample preparation than the KBr pellet technique.Index Headings: Portland cementj Tricalcium silicate (C 3 S)j Calcium silicate hydrate (C-S-H); Fourier transform infrared (FT-IR) spectroscopy; Transmission spectroscopy (TS); Diffuse reflectance spectroscopy (DRIFTS); Photoacousti...

A monomer, 3,3′‐bis (4‐fluorobenzoyl) biphenyl, was prepared in high yield in two steps from inexpensive 3‐chlorobenzoyl chloride and fluorobenzene, and polymerized by nucleophilic displacement reaction with various bisphenol monomers in tetramethylene sulfone to produce a series of high molecular weight poly(aryl ether ketone)s containing 3,3′‐dibenzoylbiphenyl (DBBP) moieties. The spectroscopic, thermal, and thermomechanical properties of these polymers and related isomeric polymers having 2,2′‐and 4,4′‐DBBP units were determined and compared to study the effects of changes in the substitution pattern of the biphenyl unit. Except for the 2,2′‐DBBP series of polymers, Tgs were found to increase with increasing linearity of the DBBP unit. The 2,2′‐DBBP series of polymers had exceptionally high Tgs due to the sterically restricted motions in the biphenyl unit caused by the 2,2′‐substitution. In addition, they also showed evidence for torsion with the 2,2′‐DBBP unit, whereas in other isomeric polymers the DBBP units are believed to be relatively coplanar. Thermal stabilities and tensile moduli for these polymers proved to be independent of substitution patterns. © 1995 John Wiley & Sons, Inc.

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