Dynamic Mechanical Analysis, fillers

Shock isolation is also possible usiag the dampiag characteristics of FZ elastomer. Dynamic mechanical analysis iadicates multiple transitions and a broad dampiag peak. This dampiag can be enhanced usiag formulatioas containing both siUca and carbon black fillers. 

It was concluded that the filler partition and the contribution of the interphase thickness in mbber blends can be quantitatively estimated by dynamic mechanical analysis and good fitting results can be obtained by using modified spline fit functions. The volume fraction and thickness of the interphase decrease in accordance with the intensity of intermolecular interaction. 

Thermal mechanical analysis (Dupont 990/942 IMA), and dynamic mechanical analysis (Dupont 1090/982 DMA) curves for a designed set of model formulations were evaluated for CTE and tensile storage modulus as a function of filler level and elastomer additive type and level. Fifteen formulations were prepared with 68-75% filler, 0-4% silicone elastomer A, 0-4% non-silicone elastomer B and the balance 17-32%. Both elastomers have Tg s below room temperature. An extreme vertices formulation design was generated by computer (Table I). 

Pasquini et al. reported that cellulose whiskers with high aspect ratio extracted directly from cassava bagasse were used to prepare NR nanocomposite films by mixing with the NR latex emulsion. The mixtures were cast on Teflon plates and dried overnight to obtain composite films. These NR nanocomposite films were not vulcanized by standard process. They found that a significant increase of the storage tensile modulus was observed upon filler addition by dynamic mechanical analysis. 

However, the overall crystallinity and melting temperature decreased with increasing filler content. Tensile and dynamic mechanical analysis measurements indicated that expanded graphite was a better hller than untreated graphite. The overall improvement in mechanical properties was not great, but the mechanical strength and stiffness of high-density polyethylene were improved by the addition of the fillers. 

Dynamic mechanical analysis has also been used to determine the mechanical and thermal properties of low-density polyethylene and ethylene-propylene-diene terpolymer containing jute filler, which had improved flexural and impact properties compared to those of the base polymer [198]. Jeong and coworkers [196] and others [195] investigated the dynamic mechanical properties of a series of polyhexamethyl-ene lerephthalale, poly(l,4-cyclohexylenedimethylene terephthalate), and random copolymers thereof in the amorphous state as a function of temperature and frequency. The effect of copolymer composition on dynamic mechanical properties was examined and the dynamic mechanical properties interpreted in terms of the cooperativity of segmental motions. 

Thongsang S, Vorakhan W, Wimolmala E, Sombatsompop N (2012) Dynamic mechanical analysis and tribological properties of NR vulcanizates with fly ash/precipitated silica hybrid filler. Tribol Int 53 134... 

Table 2.5 summarises the main applications of thermal analysis and combined techniques for polymeric materials. Of these, thermomechanical analysis (TMA) and dynamic mechanical analysis (DMA) provide only physical properties of a very specific nature and yield very little chemical information. DMA was used to study the interaction of fillers with rubber host systems [40]. Thermomechanical analysis (TMA) measures the dimensional changes of a sample as a function of temperature. Relevant applications are reported for on-line TMA-MS cfr. Chp. 2.1.5) uTMA offers opportunities cfr. Chp. 2.1.6.1). The primary TA techniques for certifying product quality are DSC and TG (Table 2.6). Specific tests for which these techniques are used in quality testing vary depending upon the type of material and industry. Applications of modulated temperature programme are (i) study of kinetics (ii) AC calorimetry (Hi) separation of sample responses (in conjunction with deconvolution algorithms) and (iv) microthermal analysis.

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