Crystallization kinetics in a homogeneous copolymer of ethene and 1-octene with appended
long chain branches has been investigated in real time by means of time-resolved light scattering under
H
V (cross-polarized) and V
V (parallel-polarized) optical alignments using a CCD camera system,
simultaneous small angle-X-ray and wide angle X-ray measurements using synchrotron radiation and
differential scanning calorimetry (DSC). The data show that in the case of crystallization at large
supercooling, a significant fraction of the crystallinity develops after the spherulites have become volume
filling. The fraction of crystallinity that develops after primary crystallization increases with crystallization
temperature. This opens up a challenge to explore the extent to which this behavior is universal in other
crystallizable ethylene copolymers as well.
(1) It is postulated that the interaction between starch and iodine in the amylose-iodine complex is of dipolar nature.
(2) A model for such dipolar interaction is proposed and the necessity for a cooperative effect is discussed.
(3) The interaction energy is calculated as a function of a parameter x and it is shown that this parameter possesses a critical value at which a ``condensation'' of iodine into the complex occurs.
(4) It is demonstrated that it is physically reasonable for this parameter to attain its critical value.
(5) It is shown that additional stabilization may occur as a result of the formation of a resonating ``polyiodine'' chain at high dipolar interaction having a I–I distance and heat of formation which compares favorably with experiment.
(6) Application of the theory is made in discussing the stability of the polyvinyl alcohol-iodine complex.
(7) The color of these complexes is discussed in terms of the theory.
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