Modulus continued specific

Reinforcing material Specific gravity Tensile Strength modulus Compressive strength, 10 psi Flexural strength, 10 psi Izod impact strength, ft-lb/in. Heat resistance continuous, Arc resistance,... 

The strain energy generated by placing a sphere in a hole of different size in a continuous medium depends on the elastic properties of the medium, specifically the Young s modulus ( ) and Poisson s ratio (a). Since, for all liquids. Young s modulus is zero and Poisson s ratio 0.5, the strain energy of substitution into a melt should be zero. This yields the following relationship between the equilibrium constants for reactions (1), Kq, and... 

This point is dealt with specifically by Krigbaum et They use a model in which the small crystallites are interconnected by amorphous chains, for which they act as cross-links. This is tantamount to assuming that the system can be treated as a dispersion or suspension of a discontinuous crystalline phase, in a continuous amorphous phase, to use the terminology of composite materials. On the assumption that the amorphous chains are under tension as the result of the process of crystallisation, they are able to account convincingly for the modulus of the two different polyethylenes they discuss. These have moduli in the range 0-5-10 X 10 Nm" ... 

In Sections 12.1 and 12.2 several important aspects of matrix and interface behavior, such as the effects of an inclusion on modulus and the effect of interfacial adhesion, were described. It is also appropriate to discuss specific molecular effects of rigid inclusions (particulate or fibrous) on a matrix, in order to demonstrate continuity between all types of reinforcements. Effects of environmental exposure on composite behavior are also briefly considered. 

Young s modulus decreases continuously from around 3,200 MPa for pure PEI to around 2,200 MPa for pure PTT. The addition of PEI affects the ciystallinity of PTT (decreases from around 27% for neat PTT to around 3% for 25 wt% blend), but the mechanism of ciystal growth is seen to be unaffected. The blends shows a syneigistic behavior in modulus of elasticity (which is attributed to a decrease in specific volume upon blending). Additionally syneigism is observed in the yield stress of PEI rich blends, and ductile nature. 

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