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A solvent and catalyst-free synthesis of a polyphosphate was accomplished. The reaction involved a gas-liquid polycondensation between phenylphosphoric dichloride and phenolphthalein. The polyphosphate was characterized by IR, 1H-NMR, inherent viscosity, thermal analysis and molar mass. Polyphosphate was stable up to 260oC. Keywords: gas-liquid polycondensation, polyphosphate

The structural characteristics of polymeric composites based on EPDM, (ethylene-propylene-dien monomer) rubber, which have various percentages of high density polyethylene, were studied by IR spectroscopy and optical microscopy, evidencing the influence of processing parameters. The EPDM rubber was vulcanized using either sulphur and accelerators or peroxides. The influence of the dynamic conditions (rotation rate during the mixing of rubber with polyethylene) on the solvent retaining by maintaing 1-24 hours in benzene, chloroform and MEC (methylethylcetone) was shown by weighing the samples. The results of research could be used for choosing the suitable compositions, processing conditions as well as the fields for application of these composites. Keywords: EPDM (ethylene-propylene-dien monomer) rubber, polyethylene,IR spectroscopy, microscopy

In the paper, a stress strain analysis in the area of central ligament of a cruciform glass-epoxy specimen is presented. Investigation was done experimentally, using strain gauges technique, by application of six gauges in the stress concentration area. The validation of a theoretical model (a special type of a finite element), which was created by authors for analysis of the laminate composite structures, was the aim of this study. A good agreement between numerical calculus and experimental results was observed. Keywords: experimental validation, finite element method, epoxy resin, lamina, cruciform specimen, strain gauges technique

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