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Recently, a robust tool for assessment of different teaching methodologies in engineering education has been developed by the consortium of the iTeach project (www.iteach-chemeng.eu). The tool was initially tested for its applicability in teaching units of chemical engineering education, evaluating several educational approaches used to deliver core knowledge and employability competences in different geographical and educational contexts. After some modifications, the framework was subjected to a wider testing, including teaching units that are part of other engineering disciplines, but also, extended to other higher education disciplines. In the presented case-study, the framework, including six metrics, was used in the assessment of two pedagogical approaches, practical instructions via lab and self-instruction delivery, applied in the teaching units Microbiology and Engineering Economy, respectively. Necessary data were collected by online surveys, carried out among four target groups of stakeholders, i.e. academics, employers, graduates and students. The results of this testing will be presented and discussed.

The basic objectives of food packaging materials are to provide safety and to pre- vent physical damage of the product, to retain or improve sensory characteristics, to offer a pleasing appearance, to be functional, to facilitate distribution, to give dimensional stability, but also to be compatible with the requirements regulated by the law. Consumers’ demands for an extended shelf life of the product, as well as increased competition in the packaging industry, foster the need for continuous growth and application of innovative solutions for food packaging. While the tradi- tional packaging acts as a passive barrier toward atmospheric effects, the innovative packaging systems offer “active” interactions with the foodstuff, providing increased shelf life and improved quality of the product. The selection of the appropriate pack- aging material is influenced by many factors, and, among many packaging materi- als offered on the market, polymer materials and articles have a significant place. On the other hand, some interactions occur between the plastics and the food in contact. The migration of the low-molecular-weight components from the polymer packaging to the packed food is emphasized when the so-called active and intelli- gent systems are used. Therefore, all the issues related to the packaging materials for food and the substances used as part of the packaging systems, are elaborated in the directives and regulations of the materials and articles intended to come in contact with the food.

Biodegradable polymers for medical and pharmaceutical application have been in the focus of scientific interest in the last two decades. Among the others, features like biocompatibility, supportive cell proliferation and biodegradation are considered as crucial in the fabrication of scaffolds in tissue engineering and controlled drug delivery systems. Polymers based on polyesters, polyethers, polyanhydrides, poly(ether esters), poly(ortho esters), poly(amino acids) are very significant for the application in medicine and pharmaceutics. Porous polymer matrices in tissue engineering encourage the growth of cells, at the same time allowing the exchange of nutrients and residuals. Drug delivery systems, where biological agent is dispersed / dissolved in the polymer matrix, act as reservoirs, while drug carriers are those systems where the active substance and matrix are chemically bonded. Of particular interest to many researchers are the systems in which degradation profile of polymer matrix is crucial in the determination of the rate by which the medicament is released. Biodegradable nanosized systems as devices of controlled release or selected targeting of active component attract significant attention. This paper provides a brief outline of biodegradable polymers, the properties important for their application in medicine, with particular interest in their hydrolytic degradation, and at the same time, it will serve as a basis for further research in this area.

Poly(l-lactic acid)–TiO2 nanocomposite films were prepared by twin-screw mixer and compression molding. Compatibility between polymer matrix and nanoparticles were improved by modification of the TiO2 surface with fluorocarbons plasma treatment. 2 and 5 were the % in weight of modified functionalized TiO2 (fTi) used in this work. Not modified TiO2 nanoparticles were also used at the same % for comparison. The nanocomposites were analyzed in terms of molecular mass, structure, morphology, thermal stability, mechanical properties and UV absorbance. It was found that TiO2 nanoparticles affected slighly the PLA molecular weight during mixing and the phenomenon was more marked for functionalized nanoparticles (fTi). All the films presented a good dispersion of nanoparticles in PLA matrix. However, a better interfacial interaction was found for nanocomposites containing modified nanoparticles, and this was reflected in the improved mechanical properties. Moreover, all the nanocomposites showed extension of UV absorption area and increase of the thermal stability. Both UV adsorption and thermal stability increased by increasing TiO2 content and at a given composition for nanocomposites containing modified TiO2.

The presence of phenolic compounds as one of the most common organic pollutants in natural water (surface and ground waters) has been detected as a worldwide problem. Very small concentrations of phenols affect the quality of both environmental and household waters, and directly or indirectly impact lives in aquatic systems and humans, as well. Most of the organic compounds, containing certain functional groups, such as amino, amines, carbonyl, hydroxyl, groups containing sulfur and others, have shown ability of adsorption on metal surfaces from aqueous solutions. Cyclic voltammetry (dE/dt = 100 mV s-1) with simultaneous monitoring of the double layer (dl) capacitance (at 100 Hz and 1 mV ac signal) was used for an adsorption study of phenol on polycrystalline gold from 0.5 mol dm-3 aqueous solutions of NaHCO3. Thus, in this study an effort was made to establish a fast method, an electrochemical procedure for qualitative and quantitative determination of phenols in natural water systems. Keywords: Electrosorption, phenol, polycrystalline gold, natural water

Polypyrrole, along with polyacetylene, polyparaphenylene polyaniline, polythiophene and other polymers structured by conjugated double bonds, is considered as one of the most attractive conducting materials for various applications, such rechargeable batteries, supercapacitors, sensors, gas membranes, magnetic shields, etc. Regarding their biocompatibility and biodegradability in addition to the possibility of controlling their porosity, as well as incorporation of different biological species, and latter by stimulation (e.g. applying electrical field) to control the release of these moieties from polymer matrix, make these polymers suitable for preparation of drug delivery systems, as well as tissue engineering applications. On the other hand, problems concerning poor mechanical properties and environmental instability could be compensated by preparation of blends, copolymers or composite materials. Systems including two components, e.g. conjugated polymers and carbons, supplement the two diverse electrochemical behaviors of both. Lately, composites of polypyrrole, with pseudocapacitance properties and/or carbons (activated carbon, carbon nanotubes) showing double layer capacitance, have been reported in the literature. So, we have made an effort to outline some of most significant results published.

Electrochemical synthesis of polypyrrole (PPy) and polypyrrole / activated carbon (PPy / AC) - composite films, with a thickness between 0.5 and 15 ?m were performed in a three electrode cell containing 0.1 mol dm-3 Py, 0.5 mol dm-3 NaClO4 dissolved in ACN, and dispersed particles of AC (30 g dm-3). Electrochemical characterization of PPy and PPy / AC composites was performed using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) techniques. The linear dependences of the capacitance (qC), redox capacitance (qred), and limiting capacitance (CL) of PPy and PPy / AC - composite films on their thickness (L), obtained by electrochemical and impedance analysis, indicate a nearly homogeneous distribution of the incorporated AC particles in the composite films (correlation coefficient between 0.991 and 0.998). The significant enhancement of qC, qred, and CL, was observed for composite films (for ?40 ? 5%) in respect to that of the ?pure? PPy. The decreased values of a volume resistivity in the reduced state of the composite film, ? = 1.3 ? 106 ? cm (for L = 7.5 ?m), for two orders of magnitude, compared to that of PPy - film with the same thickness, ? ? 108 ? cm, was also noticed.

New ABC type terpolymers of poly(ethoxyethyl glycidyl ether)/poly(ethylene oxide)/poly( d , l -lactide) were obtained by multi-mode anionic polymerization. After successive deprotection of the ethoxyethyl groups from the first block, highly hydroxyl functionalized copolymers of polyglycidol/poly(ethylene oxide)/poly( d , l -lactide) were obtained. These copolymers form elongated ellipsoidal micelles by direct dissolution in water. The micelles consist of a poly( d , l -lactide) core and stabilizing shell of polyglycidol/poly(ethylene oxide). The hydroxyl groups of polyglycidol blocks situated at the micelle surface provide high functionality, which could be engaged in further chemical modification resulting in a potential drug targeting agents. The micellization process of the copolymers in aqueous media was studied by hydrophobic dye solubilization, static and dynamic light scattering, and transmission electron microscopy.

Tri- and pentablock amphiphilic copolymers containing hydrophobic poly(D,L-lactide) block(s) and hydrophilic polyethers were synthesized in order to obtain new precursor architectures suitable for drug delivery systems. Polyglycidol-b-poly(ethylene oxide)-b-poly(D,L-lactide) possess high hydroxyl functionality provided by the linear polyglycidol block. Thus very stable hydroxyl functionalized micelles in aqueous media were obtained. On the other hand poly(D,L-lactide)-b-poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide)-b-poly(D,L-lactide) form temperature sensitive aggregates. The copolymers obtained were analyzed by SEC and NMR, and their aqueous solution properties were followed by cloud point measurements and determination of critical micellization temperature. TEM was used for particles visualization.

This study focused oil the synthesis and characterization of poly(ethylene glycol)-poly(D,L-lactide-co-glycolide)-poly(ethylene glycol) tri-block co-polymer (PEG-PDI-LG-PEG), and its modification with type-I collagen. To this aim, a PEG-PDLLG-PEG tri-block co-polymer was synthesized in two steps by reacting poly(ethylene glycol)bis(carboxymethyl)ether with thionyl chloride to obtain all acyl-halide-terminated poly(ethylene glycol) and Subsequently Coupling this compound to hydroxyl-terminated poly(D,L-lactide-co-glycolide) (PDLLG). The new carboxyl end-groups of PEG-PDLLG-PEG were subsequently reacted with N-hydroxysuccinimide (NHS) in the presence of the hetero-bifunctional cross-linking agent dicyclohexylcarbodiimide (DCC) in order to activate the co-polymer for coupling with collagen. PEG-PDLLG-PEG and its activated form PEG-PDLLG-NHS were characterized by Fourier transform infrared (FT-IR) and H-1-NMR spectroscopy. Molecular weights of the polymeric products were determined by SEC. Type-I collagen in phosphate buffer was reacted with PEG-PDLLG-NHS. The resultant product. PEG-PDLLG-Col, was characterized by FT-IR. This biopolymer was used for preparation of a suitable Surface for cell growth experiment. To measure the degree of cell proliferation, the films prepared with PDLLG. PEG-PDLLG-NHS and PEG-PDLLG-Col were seeded with L929 mouse fibroblasts. Cell growth was followed by SEM photography and quantitated by the neutral red uptake assay. It was shown that the attachment of collagen significantly increased the number of cells oil the co-polymers.

Poly(DL-lactide-co-glycolide) (PDLLGA) and poly(L-lactide-co-glycolide) (PLLGA) copolymers were prepared by bulk ring opening polymerization of lactide and glycolide and characterized by GPC, FTIR, 1H NMR and DSC. Copolymers with different molar masses at a constant lactide/glycolide ratio were used for preparation of bovine serum albumin (BSA)-loaded microparticles by the double emulsion w/o/w method. The influence of the copolymer molar mass and composition on the microparticle morphology, size, yield, degradation rate, BSA-loading efficiency and BSA release profile were studied. For microparticles prepared from PDLLGA copolymers, a biphasic profile for BSA release was found and for those made from PLLGA copolymers the release profile was typically triphasic; both of them were characterized by high initial burst release. Possible reasons for such behavior are discussed.

Dynamic electrical thermal analysis (DETA) is considered as a valuable technique for determination of polar polymer structure or changes in the polymer structure as a result of different treatments. Therefore, with this study, we wanted to check whether this technique can indicate structural changes in the PET packaging material in contact with specific media. Positive response give the opportunity to use the study of PET packaging dielectric properties after a programmed contact with some medium, to indicate possible interactions between packaging material and the medium, or packaging and foodstuff. It is also known that official simulants may have some drawbacks as migration of the potential contaminants depends on the interaction between the simulant and packaging and thus the values for measured migration could be exaggerated or too low.The possibility of DETA to indicate structural changes in the packaging material give also the opportunity to adjust the aggressiveness of some medium to the packaging, that is, some solvent, or mixture of solvents with different polarity, and thus to choose the most appropriate simulant – medium which will behave in the same way as the foodstuff.In this study we have chosen several conventional fatty food simulants: olive oil, isooctane, 3% acetic acid, and ethanol, and using the DET analysis we compared the influence of these media and the real foodstuff (mayonnaise) on the structure of poly(ethylene terephthalate) (PET) food containers.