Investigation of composition

Many cable sheaths are mamrfactured from heavily filled polymers, and TGA has been foimd to be of immeasurable value in studies of such materials and some of their ingredients. The combination of the weight-loss curve, for quantitative analysis, with the derivative, for a qualitative interpretation, has been found to be particularly powerful for these applications particularly when taken together with data obtained by the other thermal methods already discussed but also with that obtained by FTIR spectroscopy. In addition the vinyl acetate content of ethylene-vinyl acetate (EVA) copolymer used in the preparation of some sheathing formulations has been measured and used as a confirmation of grade. 

Data from FTIR spectroscopy were used to corroborate the interpretation of the first weight-loss peak for each sample as due to aluminium hydroxide fire retardant. Data from both techniques were combined with crystalline melting point data obtained by DSC and TMA, as already discussed to form conclusions about the polymers present. Usually, such 

Thermogravimetry on polymer recovered by solvent extraction has also been foimd valuable for testing initial interpretations, although sample preparation can prove somewhat time consuming. A second approach is to prepare small experimental samples with which to test the analytical interpretation. The data from these samples should verify a correct analysis or provide further insight for a second iteration of interpretation. The effort to be given to these more laborious procedures will obviously depend on whether a simple survey, or a very detailed analysis, is deemed most fit for the purpose towards which the original analysis was directed. 

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Thomason, J.L. (1990). Investigation of composite interphase using dynamic mechanical analysis artifacts and reality. Polym. Composites 11. 105-113. 

Yu. N. Bolbukh, Ye. P. Mamunya, and V. A. Tertykh, Thermomechanical investigation of composites based on 2-hydroxyethylmethacrylate and high disperse initial and modified silicas, J. Therm. Anal. Cal. 81(1), 15-20 (2005). 

Data is also available on investigations of composites of PVC/leather fibre (380) and PVC/newsprint fibre (430) as a means of utilising these waste materials. 

For the investigation of composition of the gases evolved at different stages of the volatilization, pyrolyses have been carried out with interruptions of the discharge231 - For both lignite (67% C) and hvab coal (82% C) the concentration of H2 increased but that of CO and C02 decreased, in analogy to thermal decomposition... 

Particular investigations of composites at the temperature of 800 °C confirmed the domination of the mentioned above fracture micromechanisms. At this temperature only cast modifications without thermo-mechanical and heat treatment still have satisfactory fatigue crack growth resistance. 

When selecting any analytical method for copolymers, the basic concepts described in the previous section should be kept in mind. Copolymers are a peculiar class of substances which can be characterized, to a first approximation, only by the combined investigation of composition and constitution. 

Here the interface is defined as a distinct two-dimensional boundary which defines, for instance, where a fiber ends and the binder begins. Most, but not aU, investigators of composite performance believe that an interphase region and not just an interface is developed and exists in fiber composites. One needs only to look at a few of the most noted journals on composites to find extensive discussion of the interface and interphase. Yet, after approximately 20 years what is really understood about the interphase and its effects on composite performance The authors claim that our knowledge is, at best, cursory The authors believe that this is due to a lack of fundamental knowledge about how fiber and matrix are joined. 

Dai Y, Wang Y, Greenbaum S, Bajue S, Golodnitsky D, Ardel G, Strauss E, Peled E (1998) Electrical, thermal and NMR investigation of composite solid electrolytes based on PEO, LU and high surface area inorganic oxides. Electrochim Acta 43(10-11) 1557-1561... 

Analysis of Mesoamericam plumbate pottery surfaces Nd YAG 213 nm ICP-SF-MS Quantitative analysis of slipped surfaces and comparison with NAA Investigation of compositional changes with depth Neff [56]... 

Investigation of compositional diversity among Fijian ceramics Study of climate change and population history in the Pacific Lowlands of Southern Mesoamerica Provenance determination of oriental porcelain... 

In investigations of composite materials, usually the micro- and meso-levels are particularly considered and the macro-level is characteristic for composite structures. In the book by Ashby and Jones (2005b) a more diversified system of levels has been proposed, also characterized by dimensions of observed objects. 

Development and investigation of composite electrode materials, integrating their combined benefits and overcoming associated challenges... 

Wang, Z.B., Zuo, PJ. Yin, G.P Investigations of compositions and performance of PtRuMo/C ternary catalysts for methanol electrooxidation. Fuel-Cells 2 (2009), pp. 106-113. 

Holomek, J. and Bajer, M., 2012. Experimental and Numerical Investigation of Composite Action of Steel Concrete Slab. Procedia Engineering. 2012(40), 143-147, ISSN 1877-7058, DOI 10.1016/j.proeng.2012.07.070. 

K. Siderakis, D. Pylarinos, E. Thalassinakis, E. Drakakis, Performance investigation of composite and RTV SIR coated insulators at a coastal test station, UPEC 46th International Universities Power Engineering Conference, 2011. 

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