Applications, thermally stimulated current

The book opens with the first three chapters devoted to differential scanning calorimetry (DSC), the most commonly used thermal method. These chapters cover the principles, optimal use, and pharmaceutical applications of the method. Subsequent chapters explore modulated temperature DSC, thermogravimetric analysis, thermal microscopy, microcalorimetry, high sensitivity DSC, dynamic mechanical analysis, and thermally stimulated current, all of which have attracted great interest within the pharmaceutical field. Each chapter includes theoretical background, measurement optimization, and pharmaceutical applications. 

Yoshida, F. Maeta, S. "Proposal of Asymptotic Estimation v Method Evaluating Escape Frequency Factor from a Partial Thermally Stimulated Current Curve Directly", Trans. Inst. Electr. Eng. Jpn., Vol.lll-A, No.4, pp.323-331, (1991) [in Japanese] Yoshida, F., Tanaka, M. Maeta, S. "Proposal of Asymptotic Estimation I Method with High Sensitivity to Thermally Stimulated Current Curve and its Application to New Analysis",Trans. Inst. Electr. Eng. Jpn., Vol.lll-A, No.2, pp.104-110, (1991) [in Japanese]... 

G.P. Simon, A. Schonhals, Dielectric relaxation and thermal stimulated currents, in Polymer Characterization Techniques and Their Application to Blends, ed. by G.P. Simon (Oxford University Press, Oxford/New York, 2003), pp. 96-131 J. Skolnik, R. Yaris, Maciomolecules 15, 1041 (1982)... 

Another TL application is the analysis of the electronics states in materials, which are defined by both material and technology of its production. For example, for PS different contact methods to define the electronics states in metal/PS stmctures have been aheady applied thermally stimulated depolarization currents (TSDC) and thermally stimulated current (TSC) (Ciurea et al. 1998 Anastasiadis and Triantis 2000 Brodovoy et al. 2002), optical charging spectroscopy (OCS) (Ciurea et al. 2000), and deep-level transient spectroscopy (DLTS) (Pincik et al. 1999 Tretyak et al. 2003). The mentioned methods determine the parameters of traps related with both PS material and metal/PS interface and often differ from results obtained from TL experiments. Two advantages of the TL method are that it is contactless and it can reveal the energy distribution of both bulk and/or surface states. The obvious drawback of TL is that it can only be applied to luminescent materials. 

BordaUo HN, Zakharov BA, Boldyreva EV, Johnson MR, Koza MM, Seydel T, Fischer J (2012) Application of incoherent inelastic neutron scattering in pharmaceutical analysis relaxation dynamics in phenacetin. Mol Pharm 9 2434-2441 Bptker JP, Karmwar P, Strachan CJ, Cornett C, Tian F, Zujovic Z, Rantanen J, Rades T (2011) Assessment of crystalline disorder in cryo-milled samples of indomethacin using atomic pairwise distribution functions. Int J Pharm 417 112-119 Boutonnet-Fagegaltier N, Menegotto J, Lamure A, Duplaa H, Caron A, Lacabanne C, Bauer M (2002) Molecular mobihty study of amorphous and crystalline phases of a pharmaceutical product by thermally stimulated current spectrometry. J Pharm Sci 91 1548-1560 Bras AR, Noronha JP, Antunes AMM, Cardoso MM, Schdnhals A, Affouard Fdr, Dionfsio M, Correia NIT (2008) Molecular motions in amorphous ibuprofen as studied by broadband dielectric spectroscopy. J Phys Chem B 112 11087-11099... 

Thermally stimulated depolarization (TSD), e.g. [101]. TSD is applicable to dielectric polymers that are electrets. Depolarization currents are monitored and these currents are related to the relaxation of electric charges in the sample as a function of the number of events that take place in the sample at the molecular and supermolecular level. 

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