Mechanical properties of epoxies

Table 26.11 Mechanical properties of epoxy-glass cloth laminates...

Wilson, W.T. "Effect of Radiation on the Dynamic Mechanical Properties of Epoxy Resins and Graphite Fiber/Epoxy Composites", 1986, Ph.D. Thesis, North Carolina State University, Raleigh, NC. 

Grillet et al. (1991) studied mechanical properties of epoxy networks with various aromatic hardeners. It is possible to compare experimental results obtained for networks exhibiting similar Tg values (this eliminates the influence of the factor Tg — T). For instance, epoxy networks based on flexible BAPP (2-2 - bis 4,4-aminophenoxy phenyl propane) show similar Tg values ( 170°C) to networks based on 3-3 DDS (diamino diphenyl sulfone). However, fracture energies are nine times larger for the former. These results constitute a clear indication that the network structure does affect the proportionality constant between ay and Tg — T. Although no general conclusions may be obtained, it may be expected that the constant is affected by crosslink density, average functionality of crosslinks and chain... 

TABLE 15.15 Effect of Water on Mechanical Properties of Epoxy Structural Adhesives33... 

Some authors assign good mechanical properties of epoxies to high concentrations of H bonds. First, the Young modulus of a polymer is considered to be sensitive to the presence of H bonds. The Young modulus of a polymer can be described by ... 

Other interesting examples of the behaviour of the considered samples are given in Fig. 32. Samples with high Tg which are chemically less defective have lower E25 values. These anomalies in the mechanical properties of epoxy polymers prepared at low Tcure are very difficult to understand in terms of conventional concepts of the relationship between the structure of polymer glasses with their mechanical properties. 

Structures and Dynamic Mechanical Properties of Epoxy Resins Cured... 

In this review, the effect of the cured epoxy resins on the dynamic mechanical properties of epoxy resins is discussed. 

W. J. Mlkols, J. C. Seferls, A. Aplcella, and L. Nicolais, Polymer Composites, 118, (1982) W. J, Mikols, Hygrothermal Effect on the Mechanical Properties of Epoxies and Graphite Epoxy Composites, Ph.D. Dissertation, Department of Chemical Engineering, University of Washington, Seattle, Washington (1982). 

Yamini, S. and Young, R, J., "The Mechanical-Properties of Epoxy-Resins. 2. Effect of Plastic-Deformation Upon Crack-Propagation," Journal of Materials Science. Vol. 15, No. 7, 1980, pp. 1823-1831. 

In this paper we address the area of the structure-property relations of epoxy matrices, with specific emphasis on amine-cured epoxides. In attempts to correlate the structure-property relations of amine-cured epoxides, there have been a number of studies on the mechanical properties of these glasses as a function of epoxide amine ratios and the chemical structure of the constituent epoxide and amine monomers.(1-15) Generally, there is no direct correlation between the chemistry of the epoxide and amine monomers and the mechanical properties of epoxies with the exception that as the distance between crosslinks becomes shorter, these glasses become more brittle.(1,10,15) Also, for a specific amine-cured epoxide system, the Tg is always highest for the fully reacted, highest crosslink density glass.(3,6,9,12,... 

Gojny, F. H., Wichmann, M. H. G., Fiedler, B., and Schulte, K., Influence of different carbon nanotubes on the mechanical properties of epoxy matrix composites a comparative study. Compos. Sci. TechnoL, 65, 2300-2313 (2005). 

Nak Nakamura, Y., Yamaguchi, M., Okubo, M., Matsumoto, T. Effect of particle size on mechanical properties of epoxy resin filled with angular-shaped silica. J. Appl. Polym. Sci. 44 (1992) 151-158. 

Zho Zhong, Z.-K., Zheng, S.-X., Huang, J.-Y., Cheng, X.-G., Guo, O.-P., Wei, J. Phase behaviour and mechanical properties of epoxy resin containing phenolphthalein poly (ether ether ketone). Polymer 39 (1998) 1075-1080. 

Par Park, S.-J., Seo, M.-K., Lee, J.-R. Effect of the substituted benzene group on thermal and mechanical properties of epoxy resins initiated by cationic latent catalysts. J. Polym. Sci. Part B - Polym. Phys. 42 (2004) 2419-2429. 

Wan Wang, L., Wang, K., Chen, L., Zhang, Y.-W., He, C.-B. Preparation, morphology and thermal/ mechanical properties of epoxy/nanoclay composite. Composites Part A - Appl. Sci. Manufacturing 37 (2006) 1890-1896. 

IKis Kishi, H., Kunimitsu, Y., Imade, J., Oshita, S., Morishita, Y., Asada, M. Nano-phase sfructures and mechanical properties of epoxy/acryl triblock copolymer alloys. Polymer 52 (2011) 760-768. 

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