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The transport process of charged polymer, through a nanopore in a biological membrane is studied. An expression for the polymers flow in terms of the free energy and the friction coefficient is obtained. Keywords: polymer translocation, polymer flow, nanometric pores, biological membrane

The paper presents the experimental results obtained in processing rubber waste armed with metallic insertions. The experimental results were obtained appliyng a new technology for processing rubber waste reinforced with metallic insertions. The technology presented in this paper, is based on changes of rubber mechanical properties, at temperatures in criogenic domain. Keywords: rubber, waste, processing, cryogenic domain

The Wittig reaction is amongst the most popular methods for regiospecific introduction of carbon-carbon double bonds in organic synthesis. The paper deals with the synthesis of copolymers functionalized with olefin groups by Wittig type polymer-analogous reactions in phase transfer catalysis. The copolymer bond aldehyde was reacted with phosphonium salts to give olefin groups grafted on macromolecular support. Keywords: polymer-suported Wittig reagent, phase transfer catalysed, styrene-divinylbenzene copolymers

The exposure of ethylene-propylene elastomers to the action of gamma-radiation causes the modification of chemical state of polymer matrix by the formation of oxygenated products. The accumulation of these dipoles modifies the electrical behaviour of materials, the value of resistance more than three times at increasing dose up to 200 kGy. The absorbtion/resorbtion current measurements demonstrates the wrong consequence of the inversion of polarity for applied voltages. Differences between the two sorts of synthetic elastomers (ethylene-propylene copolymer and ethylene-propylene terpolymer) were pointed out. Keywords: synthetic elastomers, EPDM, EPR, electrical properties

In this paper the transport process of charged polymer, through a narrow pore in a biological membrane is studied. The translocation time of a single-stranded polymer through a nanopore may be well computed using a physical-chemical model. The general translocation time formula is presented. Keywords: polymer translocation time, nanometric pores, biological membrane

A serials of polyaminobismaleimides with different structures, having amide groups, were synthesized by Michael addition of various diamines (4,4-diaminodiphenylether , 1,4-bis(4-aminophenoxy)benzene, 1,2-bis [2- (4-aminophenoxy)ethoxy ethane to bismaleimides. The obtained monomers and polymers were characterized by infrared (IR) and proton nuclear resonance (1H-NMR) spectroscopy. Thermal characterization of polymer was accomplished by differential scanning calorimetru(DSC) and dynamic thermogravimetric analysis(ATG). The relationship between the structure and the properties was studied as well as the reaction conditions for the synthesis of resins . Keywords: bismaleimides, polyaminobismaleimides, synthesis, thermal and electric properties

The resinic acids, the aniline, the p-aminophenol and the formic aldehyde were reacted at different molar ratios in the presence of hydrogen chlorine. There were obtained formic-aldehyde resins with aminic gropups in their chain. These low molecular mass polymers are solid, friable, soluble in most of molar organic solvents, having colors from red brown for the aniline resin to dark colors for the p-aminophenol resin. The chemical structure of these polymers was identified using IR and H-RMN spectroscopy, as well as by elemental analysis. The thermal properties were also investigated. Keywords: resinic acids, p-aminophenol, aniline, phenolic resin

This paper focuses on the relationships between the chemical structure of mesogenic polymer molecules and the temperature range over which they can form liquid crystalline phases. The purpose of this presentation is to illustrate the influence of the various types of chemical modification upon transition temperatures and to show how polymers can be designed with liquid crystalline stability in an optimum temperature range. Keywords: thermotropic liquid cristalline polymers, transition temperature, design

The paperwork presents the principal constituent equations used on study of mincing rubber waste reinforced with metalic insertion. These equations permit a study of mincing process on analytical ground, without being necessary, in some cases, to conduct experimental research. For verifying these equations, an experimental part is presented here, too . A verification of constituent equations can be done. Keywords: rubber wastes, mincing, metalic insertion, modeling equations

In this paper it is analyzed the influence of epoxy and polyesteric resins reactivity on the characteristics of two types of epoxy-polyesteric powder dyes (7024 graphite grey and 9005 signal black, according to the RAL Design Classic K 7 Card, RAL-Farben, Germany) and of two cover films obtained from them. It was observed that, with the increase of acidity index of poly-esteric resins, a decrease of powder dyes gelification time takes place, as well as the decrease of cover films elasticity and gloss, but also the increase of their tickness. The increase of the epoxy equivalent of the epoxidic resin determines an increase of the powder dyes gelification time and the decrease of the cover films thickness obtained from them. Keywords: epoxy and polyesteric resins, esteric resins, acidity index, powder dyes gelification