Date: 24 April 2011, 00:01
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This book is devoted to examining the order and disorder in polymers. Understanding these factors is important because they define diffusion properties (molecule motion speed in the polymeric matrix) and the solubility of low molecular substances in polymers. PREFACE “He knew little, but did much.” The opinion of Americans on Ronald Reagan These are well-liked and respectful words of American citizens about their president. Clearly, there are several alternatives of this expression: 1. Knew much and did much, 2. Knew much, but did little, 3. Knew little and did little. Generally, the second or third expression describes people. Let it be so that criticism and self-criticism are shown. Anton Chekhov ? the famous Russian writer, once said that “a man is a fraction, where the denominator shows his personal estimation and the numerator shows his estimation by other people”. Of course, if your personal estimation is low, the fraction will not be very small, even if a person has done little. However, let us find out the readers’ opinion about the authors of this collection and then deduce the fractions for different scientists. Some part of this collection is devoted to an important topic: the order and disorder in polymers. This is a very important factor because it defines diffusion properties (molecule motion speed in polymeric matrix) and solubility of low molecular substances in polymers. Recall that the diffusion coefficient in a glass of water equals 10?4 ? 10?5 cm2/s, in melted polymer ? 10?10, in a solid amorphous polymer ? 10?15, and in crystalline polymer ? 10-21-10- 27 cm2/s. Thus the molecule’s motion and speed at transition from liquid low molecular compound to solid crystalline polymer may vary by 20 orders of magnitude or higher. Hence, a transition from kinetic area (when the reaction rate is defined by reactivities of the substances) to diffusion area (when the situation is completely defined by reagent delivery to the interaction site and the Frank-Rabinovich cage effect) may occur. The rate of chemical processes in polymers strictly depends on the order degree in the polymer matrix. In its turn, this will affect the operation properties of polymeric materials and their storage life and reliable operation. The authors would be grateful for positive comments on the materials of the current collection, which will be taken into consideration in our future work. Prof. Bob A. Howell Central Michigan University Mount Pleasant, Michigan, USA Prof. Gennady E. Zaikov N. M. Emanuel Institute of Biochemical Physics Moscow, Russia
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