Carbon epoxy thermal properties

Pure epoxy resins, so-called basic resins, are unsuited to building applications because of their high viscosity. Modifications are necessary to achieve the required viscosity, wettability, carbonate resistance, curing rate, cost reduction and numerous other properties. However, the modifiers must be chosen so as not to impair the other valuable attributes of the epoxy resins. For example volatile solvents are unsuitable for thick coatings, because any solvent retained in the cured system will reduce the mechanical and thermal properties and the corrosion resistance. The specific property needs for a particular application may be tailored to each system to maximise the remarkable potential of epoxy resins (Dow Chemical Company, undated c). 

The storage modulus for the cured resins with different polypropylene carbonate contents (Fig. 21.20) did not change over the temperature range lower than their a-relaxation, compared with the parent epoxy resin. This implied that the epoxy matrix was toughened by the addition of PPC at no expense of its modulus but with a sacrifice to its thermal properties. The molecular weight of polypropylene carbonate... 

Loosa, M.R., Coelhoa, L.A.F., Pezzina, S.H., Amicob, S.C. Effect of carbon nanombes addition on the mechanical and thermal properties of epoxy matrices. Mater. Res. 11,347-352 (2008)... 

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)... 

The in-plane mechanical, viscoelastic and thermal properties of a satin weave carbon fabric impregnated with an amine cured epoxy resin were studied by Abot and co-workers [74]. The in-plane quasi-static behaviour including the failure modes under tension, compression and shear and all the mechanical properties including elastic moduli and strengths were determined. The viscoelastic properties including the glass transition temperature were also measured as well as the coefficients of thermal expansion. These measured properties for the fabric composites were also compared with their corresponding ones for a unidirectional composite with the same fibre and matrix. 

Tantawy and co-workers [26] investigated the effect of Joule heating on the electrical and thermal properties of conductive epoxy resin-carbon black composites. The Joule heating effect was shown to be an effective and promising method for enhancing the electrical and thermal stabilities of epoxy resin-carbon black composites for consumer use as heaters and in other electronic areas, such as effective electromagnetic shielding. 

Abdel-Aal N, El-Tantawy F, Al-Hajry A and Bououdina M (2008), Epoxy resin/ plasticized carbon black composites. Part 1. Electrical and thermal properties and their applications , Polym Compos, 29, 511-517. doi 10.1002/pc.20401. 

As discussed in Chapter 6, the incorporation of reinforcing agents or fillers into plastic formulations can, in some but not all cases, lead to variations in the molecular stability of plastics and also their thermal and thermooxidation stability. Thus, it has been observed that the addition of silica to polytetrafluoroethylene did not adversely affect polymer stability, while the incorporation of 25% of organically modified silica into polyethylene led to a decrease in weight loss of the plastic from 80% to 33.7%. The incorporation of carbon nanotubes in epoxy resins unproved their mechanical and thermal properties. It is fair to say that the effect of reinforcing agents on the thermal and thermooxidative stability of polymers must always be bom in mind when selecting polymer formulations for a particular application. 

Loos et al. [62,63] studied the effect of carbon nanotube addition on the mechanical and thermal properties of epoxy components and matrices. 

General discussions of the effect of reinforcing agents on the thermal properties of polymers include glass fiber-reinforced polyethylene terephthalate [28], multiwalled carbon nanotube-reinforced liquid crystalline polymer [29], polysesquioxane [30, 31], polynrethane [31], epoxy resins [32], polyethylene [33], montmorillonite clay-reinforced polypropylene [34], polyethylene [35], polylactic acid [36, 37], calcium carbonate-filled low-density polyethylene [38], and barium sulfate-filled polyethylene [39]. 

Tantaway et al. [65] investigated the effect of Joule heating on the electrical and thermal properties of conductive carbon black epoxy resin composites. 

Lai et al. [52] and Loos et al. [53] demonstrated a great improvement in mechanical properties and a slight improvement in thermal properties following the addition of carbon nanotubes to epoxy resins. 

Russ M, Rahatekar SS, Koziol K, Parmer B, Peng H-X (2013) Length-dependent electrical and thermal properties of carbon nanotube-loaded epoxy nanocomposites. Compos Sci Technol 81 42 7... 

Until 2003, Chen s [28], Qu s [29-31], and Hu s [32] groups independently reported nanocomposites with polymeric matrices for the first time the. In Hsueh and Chen s work, exfoUated polyimide/LDH was prepared by in situ polymerization of a mixture of aminobenzoate-modified Mg-Al LDH and polyamic acid (polyimide precursor) in N,N-dimethylactamide [28]. In other work, Chen and Qu successfully synthesized exfoliated polyethylene-g-maleic anhydride (PE-g-MA)/LDH nanocomposites by refluxing in a nonpolar xylene solution of PE-g-MA [29,30]. Then, Li et al. prepared polyfmethyl methacrylate) (PMMA)/MgAl LDH by exfoliation/adsorption with acetone as cosolvent [32]. Since then, polymer/LDH nanocomposites have attracted extensive interest. The wide variety of polymers used for nanocomposite preparation include polyethylene (PE) [29, 30, 33 9], polystyrene (PS) [48, 50-58], poly(propylene carbonate) [59], poly(3-hydroxybutyrate) [60-62], poly(vinyl chloride) [63], syndiotactic polystyrene [64], polyurethane [65], poly[(3-hydroxybutyrate)-co-(3-hydroxyvalerate)] [66], polypropylene (PP) [48, 67-70], nylon 6 [9,71,72], ethylene vinyl acetate copolymer (EVA) [73-77], poly(L-lactide) [78], poly(ethylene terephthalate) [79, 80], poly(caprolactone) [81], poly(p-dioxanone) [82], poly(vinyl alcohol) [83], PMMA [32,47, 48, 57, 84-93], poly(2-hydroxyethyl methacrylate) [94], poly(styrene-co-methyl methacrylate) [95], polyimide [28], and epoxy [96-98]. These nanocomposites often exhibit enhanced mechanical, thermal, optical, and electrical properties and flame retardancy. Among them, the thermal properties and flame retardancy are the most interesting and will be discussed in the following sections. 

XA and HM carbon fibres are Courtaulds products note that Courtaulds have ceased making carbon fibres but information on their material has been included here since other manufacturers produce fibres with similar properties, see Figure 3.1, and the thermal properties of Courtaulds materials may be relevant to these other fibres. Aramid fibres used were Kevlar 29, Kevlar 49, Kevlar Hm (du Pont). E-, R- and D-glass fibres were used and Tyranno SiC and Nicalon SiC ceramic fibres (Ube Industries and Nippon Carbon, respectively). 934 (Fiberite) and MY720/HT976 (Ciba Geigy) epoxy resins were used (among others), as was polyester resin and acid cure phenolic resin. 

Alloui, A., Bai, S., Cheng, H., Bai, J. - Mechanical and electrical properties of a MWNT/epoxy composite . Composites Sci. Technol. 62 (2002) 1993-1998 Ruoff, R., Lorents, D. - Mechanical and thermal properties of carbon nanotubes . 

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