Creep Epoxy matrix

The increase of the glass-transition temperature and the decrease of creep of epo3 polymers with 10% SKD-KTRA demonstrate the effect of the rubber upon the epoxy matrix itself. Such abnormal behavior of EEC can be explained thermodynamically. An SKD-KTRA content of 10% in ERG ensures thermodynamic conditions for separation of the... 

The other information was obtained for the epoxy-diabase composite. Figure 80 shows that, together with the small deformation jumps equal to 0.6-1.2 p.m in size, peculiar to neat epoxy matrix, the larger periodic variations of creep rate arose with L = 4-6 im. These deformation jumps were associated, undoubtedly, with the diabase particles of the same size. The presence of solid diabase micro-particles introduced a new heterogeneity level into the structure. The increased microshears could occur due to weaker interfacial polymer layers and breaking adhesion between polymer and diabase. 

H. Otani, S. L. Phoenix, and P. Petrina, Matrix Effects on Lifetime Statistics for Carbon Fibre-Epoxy Microcomposites in Creep Rupture, Journal of Materials Science, 26, 1955-1970 (1991). 

It has been demonstrated that polydiacetylene single crystal fibres are relatively perfect and have excellent molecular alignment. In consequence they display high values of stiffness and strength and are very resistant to creep. It has been shown that such fibres have considerable promise as reinforcing fibres in an epoxy resin matrix and the study of such composite systems has enabled considerable fundamental information to be obtained concerning the mechanisms of fibre reinforcement. 

Highly cross-linked epoxy resins combine high strength stiffness thermal, chemical, and environmental stability adhesion low weight processability excellent creep resistance and favorable economics. These resins are widely applied as coatings, casting resins, structural adhesives, and matrix resins of advanced composite materials. The broad spectrum of applications ranges from the automotive and aerospace industries to corrosion protection and microelectronics. 

The low density of these fibres - about 0.97 g cm - means that in terms of specific stress and specific modulus (i.e. on a mass per unit length basis) they rank very highly. However, they are limited in composites by their low melting temperatures (about 140°C), tendency to creep, and the need for special surface-activation processes, such as corona discharge treatment, to develop adhesion to matrix polymers. They are sometimes used alone, but more often in hybrid yam and fabric stmctures with glass or carbon fibres in an epoxy or unsaturated polyester resin matrix to improve the impact resistance and energy absorption. Curing temperatures should not exceed 125°C. 

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