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A new type of polyurethane metal-complex was prepared by incorporating the transition metal ions such as copper (II), cobalt (II) and nickel (II), into polyazomethine-urethane-urea, containing functional groups. Polyazomethine-urethane-urea (PAMU) was synthesized from 5,5’-methylene-bissalicylaldehyde (MBS) by reaction with an urethane prepolymer based on polyethylene adipate diol (PEA), hexamethylene diisocyanate (HDI) and ethylene diamine (EDA), in DMF as solvent, using 0.5 wt % dibutyltindilaurate (DBDTL) as catalyst. The polymeric Schiff base was converted to the chelates of the metal salts. This complex was performed by mixing of the polyazomethine-urethane-urea, containing functional groups, with the metal salts in DMF as solvent. The polyurethane metal-complexes were characterized by FT-IR spectroscopy and elemental analysis. The polymer property investigated was their thermal stability which was studied by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The aim of this work is to present a general idea of the various methods of preparation, properties, and applications of metal-containing polyurethanes. Keywords: polyazomethine-urethane-urea, chelate polymers, metal-polymer complex

The applications of membranes and membrane processes in advanced separations from biotechnology have gained lately a great importance determining their inclusion among the top technologies. This paper presents an original variant for preparation of some affinity membranes from acylated polysulphone and brominated polyphenileneoxide, with immobilized starch as affinity ligand for biospecific separations. Keywords: membranes, phase inversion, affinity ultrafiltration , ligand

The aim of this paper is to present a proper methodology for obtaining active mould parts. The originality of the paper consists in the fact that building these active objects starts from some distinctive marks (machine parts) for which there’s no technical documentation. Using reverse engineering procedures (scanning and reconstruction) for polymeric material machine parts and rapid prototyping procedures by material sampling, we will finally obtain both the wanted distinctive mark and its active elements. Keywords: reverse engineering, rapid prototyping, polymeric material, mould

A series of poly(maleic anhydride-alt-vinyl acetate) conjugates with alkylating agents were evaluated regarding antitumoral activity, biodistribution and organotropic effects. The synthesized conjugates exhibits a significant antitumoral activity expressed as ATR (average tumor retention). In addition the obtained macromolecular compounds show a prolonged half-life in sanguine serum and accumulation in tumoral tissue. The last effect is supposed to be enhanced by EPR (enhanced permeation and retention) effect. The analyzed compounds also exhibit some organotropic effects such as the increase of liver, spleen and kidney weight. The LD50 values of the alkylating agents and conjugated ones proved that the coupling reaction decrease the intrinsic toxicity of the alkylating agents. Keywords: poly(maleic anhydride-alt-vinyl acetate), antitumoral activity, EPR effect

New chemically modified polysulphones with both N-phenacyl-4, 4’-bipyridinium bromide and N-alkylacetate-4, 4’-bipyridinium bromide derivatives, have been synthesized by chemical modification reaction of chloromethylated polysulphones with various N-substituted monoquaternary-4, 4’-bipyridinium bromides. The structure of the modified polysulphones was confirmed by elemental analysis and 1H-NMR spectroscopy. Various reaction conditions were checked in view to obtain soluble polymers. Key words: chemically modified polysulphone, chloromethylated polysulphone, N-phenacyl-4, 4’-bipyridinium bromide, N-alkylacetate-4, 4’-bipyridinium bromide, viologen

Composite materials are sometimes harder to machine than metals, because they are anisotropic, not homogenous and their reinforcing fibers are very abrasive. Significant damage to the work piece may be introduced and high wear rates of the tools are experienced while machining. A presentation of the data obtained through experiments and an analysis of the drilling moments when machining composites will be made in this article. Keywords: the polymeric composite materials, cutting, drilling moments

The paper presents the parameters of the ultrasonic welding process of some combinations of materials. These parameters can be divided intro three categories: technological, mechanical and acoustical. A particular attention has to be paid to the technological and acoustical parameters, since they influence the quality of the welds. Keywords: welding horn, energy director, near field, far field, static force

The paper presents a methodology devoted to statistical analysis of welding characteristic process parameters in high frequency for Polyvinyl Chloride. The experimental values for technological parameters assure a high stability during the control processes in production as well as a high quality of joint welding. Key words: high frequency, welding, polymers, process

The characterization study of the molecular structure for some Mannich type condensates, obtained by the replacement of the acid catalysis, is presented. The characterization of the condensation products was conducted by IR and MNR spectroscopy. For the amino-salicylic-formaldehide condensate, the possibility to be used as an activating agent on a standard structure of butadienstyrenic rubber reticulated by a classic vulcanization system based on sulphur and sulphenamide was demonstrated. Keywords: Mannich condensates, structural analysis, vulcanization activating agent

In this paper the authors propose a new method to determine the properties of a composite material made from two different components: fiber glass cloth and resin. On the separation surface between the two materials it is assumed that the continuity conditions concerning the tensors of stresses and strains between these two components are totally satisfied. The constitutive equations were determined for each material as functions of these components with respect to a local system of reference. Medium stresses and strains were defined in order to establish the properties of the material as a whole. Considering the interdependence existing at the level of those properties the constitutive equations of the composite have been found. Mathematical expressions for elastic modulus and Poisson’s ratio have been also determined. A loading with forces applied on a longitudinal as well on a perpendicular direction face to the fibers direction of the composite is considered. We find out that the elastic properties along the fibers of the composite are closer to the properties of the reinforcing fibers and the elastic properties perpendicular to the fibers of the composite are closer to the matrix properties. Keywords: composite, elastic properties, constitutive equations