Crystallinity parameters

From a mechanical point of view the polymer may be regarded as a composite consisting of an alternative stiff (crystalline) and soft-compliant (disordered) elements. Given the geometrical arrangement of these two alternating phases and the hardness value of both of them, the arising question is to predict the hardness value of the material. On the other hand, it is known that density is a crystallinity parameter... 

Taking the crystallinity parameter QA (external standard [6]) as a measure for content of crystallized zeolite. Starting Si02/Al203-ratio in the reaction mixture was 69. The QAi-values of about 1 are representing a tranformation of 100% into the zeolitic material. 

The conversion rates of n-hexane are shown as a function of the crystallinity parameter Qai for different temperatures. We found that the catalytical activity increases simultaneously with the increased crystallinity of the composites, the crystallization products. According this linear correlation it can be concluded that the catalytical active sites, the acidic centers in the zeolitic framework, are always, independent of the crystal content of the composite material, accessible for educt of the test reaction, the n-hexane molecules. This leads to the assumption that the crystallization must start on the interface (at the phase border) between the solution (contains the alkalinity and the template) and the solid (porous glass) surface and has to carry on to the volume phase of the glass resulting finally in complete transformed granules. 

I (HTA) solids I I leaching concentration % crystallinity parameter (nm) total (NMR) 0 total y = Si/Al Amorphous phase... 

Changes in the three crystalline parameters, a, b and c, are given in Table 2. It is shown that all three parameters increase simultaneously during the reaction. This Implies that the increase in the unit cell dimension, and then the insertion of zinc, is directionally random. 

But, evidently, more is learnt about the crystalline parameter effects on detonations. 

Concomitant with improvement of crystallinity parameters such as sharpness of diffraction pattern and coherence length with increased drawing or stretching of CP fibers and films is an enhancement of the conductivity. This is seen for instance in the representative data for Poly(thienylene vinylene) (P(TV)) in Fig. 9-6(aV Results for nearly every other common CP, e.g. P(Py) 1319], are similar, with increased conductivity leveling off at draw ratios of ca. 5.0. 

From these liquid crystalline parameters, one can estimate the steady-state thermal nonlinear coefficient 2 (7) defined by... 

In order of increasing crystallinity parameter (increasing disorder ) and Needle coke, calcined at 1400 C. 

It is most remarkable that the XRD and IR 550 cm band data, which are crystallinity parameters, are strictly correlated with Nj and p-xylene adsorption. This fact indicates that the letters are mainly dependent upon the overall crystallinity. 

Tra] Traore, K., Kappler, J.P., Study ofthe Variation of die Crystalline Parameters of Solid Solutions of Manganese, Cobalt, Nickel and Iron Borides, as a Function of their Composition (in French), Bull. Soc. Chim. Fr, (9-10), 419—425 (1979) (Crys. Structure, Experimental, 16)... 

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