Blends based on LDPE and chitin or chitosan were prepared under high-temperature shear deformations in a rotor disperser at different initial ratios of the components. Although one of the components is an infusible polymer (polysaccharide), the powder blends were obtained. The composition of the powder fractions was shown to be identical to the original blend composition. It was found that the addition of poly(ethylene oxide) to the mentioned blends improves the biodegradability of the polymer materials and extends their application areas.Using various physicochemical methods, the structural and morphological changes in the polymer compositions under the action of shear deformations were examined, the mechanical characteristics of prepared films were determined, and also the features of their bio-, thermo-, and photo-oxidative degradation were studied.

In this paper the magnetic field dependence of the resonant frequency, f res , and frequency of maximum absorption, f max , for a ferrofluid sample, for polarizing fields both perpendicular to and parallel with the axis of a coaxial cell, are presented for the first time.Measurements of the complex magnetic susceptibility,as a function of frequency, f (Hz), over the range 100 MHz-6 GHz and external polarizing field, H (kA m −1 ), up to approximately 100 kA m −1 , are obtained by means of the coaxial transmission line technique. The presence of ferromagnetic resonance in the ferrofluid, (at a frequency f res ) is found for all values of the polarizing field and the influence of demagnetizing effects on f res is accounted for. The dependence of f res on H is found to be linear and an average value of internal anisotropy field, H A , and the corresponding magnetic anisotropy constant,K, are determined.The susceptibility component profiles obtained for both cases of polarization are similar to those obtained in an analogous theoretical study of dielectrics subjected to an external electric field.

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The mechanical and rheological behavior of dynamically vulcanized PP/EPDM blends is examined and compared with those of unvulcanized blends. The effect of blend ratio and dynamic vulcanization of EPDM rubber on tensile properties and flow are investigated. The mechanical properties of the blends are strongly influenced by the blend ratio. With the increasing of EPDM content the value of yield stress in a solid state decreases with the elastomer volume fractions less than 0.45 for the unvulcanized blends. For the dynamically vulcanized blends the interval of EPDM content, at which the yield peak is seen, is rather limited below 0.25 elastomer volume fractions. It is shown that dynamic vulcanization changes the deformational behavior of PP/EPDM blends. The rheological properties of dynamically vulcanized blends depending on the ratio of the components may be similar to the properties of polymer composites containing the highly disperse structuring filler. The distinction between the rheological behavior of unvulcanized and dynamically vulcanized blends is related to differences of their structures and viscoelastic characteristics of unvulcanized and vulcanized EPDM phase.

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