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The paper presents the results by application of one method to study the behaviour of packaging material in contact with food products, using different type of adhesives and different types of films for the package manufacturing. The presented method is based on primary aromatic amine determination using spectrophotometer analyze. Three different types of adhesives and three types of different films were considered for testing the migration of aromatic amines. The test was made in the same conditions for each product. Results are used for selecting optimum for material and technology in packaging of food and drinks products by multi-layer lamination in flexible approach. Key words: packaging material, adhesives, migration limit, aromatic amines, food products

Currently the leather industry has to face very high costs to treat and eliminate wastes. Therefore, the aim is to treat organic waste (protein and cellulose) by biochemical processes in order to be recycled in industry and agriculture. All treatments applied to waste mainly aim at substantially reducing environmental pollution. Worldwide research on leather recycling is directed towards obtaining protein composites by biochemical treatments using microorganisms/enzymes and obtaining protein hydrolysates and protein binders with different uses. Leather, even in the form of waste, is a valuable protein source for many areas: leather industry, automotive industry, agriculture, animal husbandry, pharmaceuticals, cosmetics, etc. Organic biopolymers are a source of raw materials for agriculture, as protein waste composition provides sufficient elements to improve the composition of and remediate degraded soils, and plants can benefit from elements such as nitrogen, calcium, magnesium, sodium, potassium, etc. This paper presents a new pilot-scale technology for biochemical hydrolysis of tannery waste and obtaining protein biocomposites - multicomponent systems of protein and cellulose biopolymers with application in the footwear industry and in agriculture for the remediation of degraded soils. Keywords: biotechnology, protein wastes, cellulose, biopolymer, tannery

The paper presents a study about obtaining materials with prolonged biocidal effect based on styrene-butadiene block-copolymers (SBS) grafted with methacrylic acid (ACM) and coupled with antibiotics from the ampicillin group. The IR spectroscopy and the elemental analysis were used to confirm the structure of SBS block-copolymers grafted with methacrylic acid and of the medical ones. The content of grafted methacrylic acid was about 18.8 % in accordance with the 1,2 enchained butadiene content, proving that the methacrylation polymer-analogous reaction takes place at these pendant vinyl groups of the polybutadiene chain. The concentration of the methacrylic acid-ampicillin pendant group is about 38 % and corresponds to the theoretical calculated one. The antibacterial testing of the synthesized polymers showed that the final reaction product has a relatively high biocidal activity on gram-positive and gram-negative microorganisms. Keywords: styrene-butadiene block-copolymers, methacrylic grafting, polymer with antibiotic effect

In this paper we study the non-uniformity that appears in the composite bars reinforced with fiber glass fabric. We defined a factor which characterizes the non-uniformity from the composite materials. We will give a formula for calculating this coefficient and a formula for the elasticity modulus of the composite bars, with two zones in which the volumetric proportions of reinforcement are different. We compared the theoretical results, which give the values of the uniformity coefficient and elasticity modulus, with experimental results obtained for three sets of samples made from ambresit and reinforced with fiber glass fabric. Keywords: composite materials, non-uniformity coefficient, elasticity modulus

Over the last years the use of bioabsorbable materials in orthopaedic surgery has increased exponentially. One of the first surgical interventions to take benefit from these absorbable materials was the reconstructive surgery for the anterior cruciate ligament (ACL) of the knee, meaning the use of interference screws for the primary fixation of the ligament graft. The aim of this paper is to present the main types of screws of this kind, used in current practice, the preferred manufacturing materials and to evaluate the standard implantation procedures in terms of the stability they ensure to the ligament graft. Keywords: bioabsorbable screws, ACL reconstruction, ligamentoplasty

The present study pursues the influence of polyelectrolytes based on maleic co-polymers with styrene and vinyl acetate under the form of natrium salt, on the colour parameters CIEL*a*b* of the Melana type polyacrylonitrile fibers dyed with Methylene blue. The work is part of a study on the metachromacy of cationic dyestuffs at dyeing the polyacrylonitrile fibres in the presence of cationic polyelectrolytes. The colours attributes are analyzed in terms of the tinctorial conditions: polyelectrolyte character and concentration, dyeing temperature and during time. Keywords: maleic polyelectrolytes, polyacrylonitrile fibres, colour differences, tinctorial parameters, methylene Blue

The introduction of the thermo and fotopolymerizable acrylic resins for the manufacture of total prostheses base has revolutionized dentistry in the 20th century. Thermopolymerizable acrylic resins (methacrylic acid derivatives) are found to have a low degree of toxicity on oral tissues after resection of the lower facial floor. It raises the question of thermo and fotopolimerizable acrylic resins toxicity compared with transplanted tissues from outside the oral cavity, in these cases compared with free osseomiocutaneous fibular flap. With the help of these resins, the restoration of the mastication, swallowing, phonation and physiognomy functions was achieved. The impact of free flaps in reconstruction of the mandible and oral floor and osseointegration of dental implants ensuring the stability of dentures are remarkable, allowing the reconstruction of the lower facial floor in a very high degree and the restoration of all functions. Keywords: acrilic resins, reconstruction lower floor

In this study, the ethylene propylene terpolymer elastomer (EPDM) was chemically changed by sulphonation which was subsequently used in preparing compounds by adding neutralization agents, ionic and non-ionic plasticizers, fillers, and polyolefines with the view to obtain an ionic thermoplastic elastomer based on sulphonated EPDM. The chemical changes in EPDM were revealed in the following ways: measurement of sulphonation reaction yield, FTIR analysis and tests for physical-mechanical characteristics of the unchanged and chemically changed EPDM. The extent to which the neutralization agent, ionic and non-ionic plasticizers, filler, polyolefines are influencing the characteristics of the resulted products was determined with the purpose of selecting the best types of ionic thermoplastic elastomer based on sulphonated EPDM. The new type of thermoplastic ionic elastomer can be processed by adequate techniques for the thermoplastic materials. Key words: chemical change, sulphonated EPDM, thermoplastic ionic elastomer

This paper presents the investigation of the catalytic agent influence on the crystallinity degree of polymers (metallocene polyethylene). Differential scanning calorimetry was the method used to determine the crystallinity. It was underlined that the catalyst has a great influence on the crystallinity of metallocene polyethylene. The results are in good agreement with the preceeding ones [4]. Keywords: polymer, metallocene polyethylene, crystallinity, differential scanning calorimetry, baseline method, First Law method

Three aromatic silicon-containing poly(1,3,4-oxadiazole-amide) were synthesized by solution polycondensation reaction of aromatic diamines containing performed 1,3,4-oxadiazole ring with a diacid chloride incorporating diphenylsilane unit. All polymers are soluble in polar organic solvents such as N-methylpyrrolidinone, dimethylformamide or dimethylacetamide. Thin films having good mechanical properties were made by casting polymer solutions onto glass substrates. These polymers exhibit high molecular weights and narrow molecular weight distribution. They are highly thermally stable, their decomposition being above 415°C. Glass transition temperature (Tg) is within the range of 246-346°C. The values of Tg, tensile strength and elastic modulus were correlated with the conformational rigidity parameters. Absorption and photoluminescence properties were also measured and discussed. Keywords: aromatic silicon, poly(1,3,4-oxadiazole-amide), aromatic diamines