Dynamic mechanical analysis, for

Sepe, Michael P., Dynamic mechanical analysis for plastics engineering, pp. 6-16 (1998)... 

Lu El, Obeng Y, Richardson KA. Applicability of dynamic mechanical analysis for CMP polyurethane pad studies. Mater Charact 2002 49(2) 177. 

In dynamic mechanical analysis for thermosetting systems the principal use is to monitor the glass-transition temperature (Tg). In a DMTA Tg is defined as the maximum in loss modulus, loss compliance or loss tangent. For example. Figure 3.57 (Prime, 1997a) shows the various transitions for a cured magnetic ink coating that had previously been cured under air and N2. 

The use of dynamic mechanical analysis for the development of polymeric systems as medical devices has been described by several authors. In one report, Silver et al. (82) examined the physical properties and hemocompatibility of polyurethanes containing polyethylene oxide macrogols. Using this technique, a series... 

Whereas there have been several applications of dynamic mechanical analysis for the characterization of the viscoelastic and mechanical properties of biomedical polymers, the characterization of pharmaceutical polymers has not received similar attention. One possible reason for this disparity has been the relative unavailability of appropriate sample geometries for pharmaceutical systems. However, the availability of newer geometries should address this problem. In spite of these difficulties, several studies have successfully employed dynamic mechanical analysis for the characterization of pharmaceutical systems and some of these are described in the following paragraph. 

M. P. Sepe, Dynamic Mechanical Analysis for Plastics Engineering, Plastics Design Library/ William Andrew, New York, 1998. 

Car Carlowitz, B. Kunststoff-Tabellen. 4. Auflage, Carl Hanser Verlag, Munich, Vienna, 1995. 98Sep Sepe, M. Dynamical mechanical analysis for plastics engineering. Plastics Design Library, Norwich, 1998. 

Figure 9.38 Tan d vs temperature obtained by dynamic mechanical analysis for both solid poly(methyl methacrylate) (PMMA) and porous PMMA with micro- and nanoporous structures.

It is well known that adhesives need to be low-modulus elastomers, so that the resin formulation has to be designed to give, after UV-curing, a soft material with a low glass transition temperature (Fg). Fig. 3 shows some typical elastic modulus E) and tan S profiles recorded by dynamic mechanical analysis for a UV-cured polyurethane-acrylate which is suitable for adhesives applications, based on its E and Tg values. It is quite soft, as shown by its Persoz hardness value of 50 s, on a scale that goes up to 400 s for glassy materials. 

Dynamic experiments. Often a viscoelastic material is subjected to stresses or strains, which change over time. When experiments are set up to mimic such conditions, they are referred to as dynamic experiments or dynamic mechanical analysis. For transient experiments, the time scale is qualitatively proportional to the inverse of the test frequency used for dynamic experiments-We will consider the above equations with respect to a simple sinusoidal stress as is often imposed by common commercial test machines. 

Odlyha, M., Foster G., Hackney, S., and Townsend, J., Dynamic Mechanical Analysis for the Evaluation of the Deacidification Treatment of Painting Canvases, J. Thermal Analysis, 50(l-2) 191-202 (1997)... 

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