Interfacial thermal properties

KE Ikeda, M., Suga, H., and Seki, S., Thermodynamic studies of solid polyethers 5. Crystahine-amorphous interfacial thermal properties, Polymer, 16, 634, 1975. 

Interfacial Thermal Properties of Cross-Linked Polymer-CNT Nanocomposites... 

Both solution and interfacial methods of polymerization produced block copolymers having essentially identical mechanical and thermal properties. Below, the dynamic mechanical results are presented, followed by thermal analyses for each of the compositions AS/AC, SS/AC, and TS/AC. 

The chapter focuses on the studies that have been carried out on the processing and properties of CNT-PMMA composites. The various composite fabrication methods used by different researchers have been described followed by a discussion of the mechanical, electrical and thermal properties of CNT-PMMA composites. The key issues of CNT dispersion and interfacial adhesion between CNT and polymer matrix that are essential to develop these advanced composites have also been discussed. Some new ideas in this direction have also been proposed. 

The physical and thermal properties of the gas and liquid, interfacial area and liquid holdup, physical mass transfer coefficients, diffusion coefficients, and volumetric flow rate of the liquid are independent of temperature and conversion. 

Combination of several properties is becoming increasingly important in modem industry. One example may be taken from electronics, where in addition to mechanical properties and electric resistance, themial stability and conductivity are important requirements. It was estimated that the increase of temperature by 10°C reduces time to failure by the factor of two." A finite analysis model was developed which accounts for the following properties of filled composites microstructure, effect of particle shape, formation of conductive chains, effect of filler aspect ratio, and interfacial thermal resistance. The predictions of the model indicate the most... 

In a commercial context, the end use dictates the properties desired. For solution applications, the rheology of the polysaccharide, its ability to retain water, and its gelling tendency are often the most important. For solids applications, the thermal properties (e.g., and T ), the mechanical properties (e.g., stiffness, tensile, texture, and adhesion), and other features such as water content, crystallinity, and spatial heterogeneity are relevant. Many polysaccharides are used in interfacial applications, in which case the surface-active properties of the polysaccharide are important. 

Camp (19) investigated the morphology of ice growth on different substrates (glass, aluminum, Lucite, gold) and concluded that the two dominant factors determining interfacial ice structure are the temperature of the interface and the material of the substratum, but not its thermal properties. It is not known if the different ice morphologies described by Camp correspond also to differences in the electrochemical interface phenomena. 

Another approach extensively apphed in recerrt years to improve the ion conductivity ((, lithiirm ion transference number (C), mechanical properties, and the electrode-electrolyte interfacial stability of a polymer electrolyte is the addition of inorganic or ceramic fillers into the polymer-salt complexes (Capiglia et al., 1999 Kim et al., 2003 Chen-Yang et al., 2008 Croce et al., 2001 Rahman et al., 2009 Shen et al., 2009 Zhang et al., 2011 Munichandratah et al., 1995 Wiec-zorek, 1992). Micro and nano-sized inorganic filler such as silicone oxide (SiO ), alumina (AI2O3), ceria (CeO ), and so on are incorporated into PEO-salt complex in an effort to improve the mechanical, thermal stabihty, and ion conductivity of PEO-based polymer electrolytes. The effect of nano-fillers on the thermal properties of the PEO-based polymer complex varies with the type of nano-particles as well as the polymer-salt complex host matrix. 

The essential reasons for their significant thermal performance are good radial distribution of gas and flowing solids and large interfacial area available for heat transfer. Thermal properties have been smdied experimentally [7,32-34], and theoretical models have been proposed [7,32]. The heat transfer properties of gas-flowing solids-fixed bed contactors not only depend on gas and solids flow rates and type of packing, but also on the portion of static holdup and axial dispersion. 

The authors [32] took into account the axial dispersion in both phases through the number of overall transfer units (NTUs), which consists both of the number of true transfer units determined by the interfacial transfer rate and the number of dispersion units. The column was divided into sections in which temperatures and thermal properties of both phases were approximately constant. 

Acosta, J. L., Ojeda, M. C., Morales, E., and Linares, A. 1986. Morphological, structural, and interfacial changes produced in composites on the basis of polypropylene and surface-treated sepiolite with organic-acids. 2. Thermal properties, loumal of Avolied Polymer Science 31 1869-1878. 

Samal et al. [35] described the properties of PP/banana-glass fiber composites and concluded that glass fiber addition led to improved mechanical performance of the composite and decreased water uptake. They also reported better interfacial adhesion and thermal properties with compatibilizer addition and hybridization. 

Yang, K., Gu, M. The Effects of triethylenetetramine grafting of multi-walled carbon nanotubes on its dispersion, filler-matrix interfacial interaction and the thermal properties of epoxy nanocomposites. Polym. Eng. Sci. 49, 2158-2167 (2009)... 

Among various nanoparticles like clay minerals, carbon nanotubes and silica nanoparticles are more often used in enhancing physical, mechanical and thermal properties of polymers [7, 8]. Uniform dispersion of nanoparticles produces ultra-large interfacial area per volume between the nanoparticle and polymer. 

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