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The population growth and the limited reservoir of fossil resources have ignited the attention of scientific communities and entrepreneurs to produce alternative products with raw-materials from renewable sources. In this work, proteins derived from the recycling of waste textiles were studied as raw-material in the synthesis of thermosetting polymers of phenolic type (phenol-formaldehyde resins) suitable for use as adhesives in the production of wood-based panels. The physical, thermal, and morphological properties of the thermosetting polymers were investigated. For comparison reasons, a typical phenol-formaldehyde (PF) resin was also presented in this study. In detail, the chemical bonds between raw-materials and PF resins were verified with Fourier Transform Infrared spectroscopy (FTIR). The curing performance and thermal stability of the thermosetting PF resins were studied with Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA), respectively. Wood-based panels were prepared and tested at a lab scale following a simulation of the industrial practice. Optical Microscope and Scanning Electron Microscopy (SEM) were applied for the study of the interaction between PF resins and woodchips at the lab scale. It was found that the resins were successfully prepared. The maximum curing temperature of the experimental resins was shifted to higher values than the control PF. According to the TGA results, the protein-based resins seem to lose mass with a lower rate, which denotes that they are more thermally stable than a typical PF resin. It can be concluded that protein from waste textiles can effectively replace part of the petrochemical phenol in the PF resin synthesis, thereby increasing the bio-content of the PF resin and making them more friendly to the environment.

Phenol-formaldehyde (PF) resins are widely used in wood-based applications by reason of their heat and water resistance, high mechanical strength and chemical stability. Challenges regarding the environmental impact of petroleum-based resources lead to an increased interest of developing new resins where components such as phenol are replaced with renewable materials. This work evaluates the environmental impact of phenol-formaldehyde resins using an organosolv lignin as phenol replacement. Two life cycle analysis (LCA) boundaries (i.e. Cradle-to-Gate, Gate-to-Gate) are studied for PF resin having different substitution levels of phenol: 0%, 40% and 100%. The LC Soft (ICAS) is used for the LCA, which provides information regarding the carbon footprint (CF), fifteen environmental impact categories (e.g.: soil, water, air, human toxicity) and the life cycle inventory (LCI) contribution. The results show improvements for all environmental impact categories for the lignin substituted resins compared to PF resin, confirming the significant role of lignin. Moreover, the impact of the raw materials (Cradle-to-Gate) is significantly higher than the impact of the production process (Gate-to-Gate).

Economic activity that takes environmental protection into account and uses the environmental benefits of an area or country may continuously combine growth with sustainability thereby providing prosperity and societal quality. This paper aims to complement European research on Bioeconomy by reviewing current situation and future trends in Greece. Current data testify that there are significant opportunities for Greece to progress towards a lucrative economy based on renewable resources. The effective growth of such Bioeconomy in Greece depends on the successful cooperation of all stakeholders (state, business, citizens). This is the first study that provides a numerical analysis of the Bio-economy opportunities for Greece and may constitute the foundation for future research, suggestions for policy measures and strategic planning

The last decades, investigators have been striving to find alternatives to materials and products from fossil sources in response to the need to get independent from petroleum. So far, the most attractive renewable source has been found to be biomass and especially wood that is easily accessible and offers a wide range of building blocks with diverse chemistries and structures that can then be used to build materials for the modern world. In this study, wood from Aspen, Pine and Birch as well as a mixture of Spruce and Pine was subjected to torrefaction and the fraction of the condensables with a dew point above 140 °C was used for the partial replacement of phenol (up to 40% wt) in the synthesis of resol phenol-formaldehyde resins suitable to be used as adhesives in the manufacturing of plywood panels. The condensables and the resins were subjected to typical lab analysis and thermal study with TGA and DSC while the plywood panels were tested and evaluated according to the European standards used by the relative industry. It was found that the studied torrefaction condensables may be successfully used in this application while the one from pine was the best performed overall.

Scientists today are intensively seeking alternatives to petrochemical materials. Among others, lignin is a promising candidate because it is available in large quantities while its chemical structure makes its use possible in a variety of chemical reactions. Lignin, received by numerous methods from various feedstocks, is a promising material for the synthesis of many products like active carbon, thermosetting and thermoplastic polymers, surfactants, phenolic chemicals, etc. In this paper, the potential of using Biolignin – a trademarked organosolv lignin from straw prepared by Compagnie Industrielle de la Matière Végétale (CIMV; Neuilly-sur-Seine, France) – in the synthesis of phenol-formaldehyde (PF) resins was studied by CHIMAR HELLAS S.A. (Kalamaria, Greece). Before its use, Biolignin was further purified and subjected to mechanical treatment for the reduction of its particle size in order to increase its reactivity. The effectiveness of the treatment was verified by atomic force microscopy (AFM) measurements that were carried out by SYNPO Company (Pardubice, Czech Republic). Resol phenolic resins were prepared with various substitution levels of phenol up to 80%. However, their synthesis process was smooth only up to the substitution level of 50%. The properties of the resins were determined with typical lab analysis. Their thermal behavior was studied with differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) measurements that were conducted by the Aristotle University of Thessaloniki in Greece. Their bonding ability was evaluated by CHIMAR HELLAS via their application in the production of plywood panels of three layers that were prepared following a simulation of the industrial process. The panels were tested for their properties according to the relevant European standards, while their performance relative to fire was studied with cone calorimetry measurements that were performed by the Latvian State Institute of Wood Chemistry (LIWC; Riga, Latvia). All results were compared with that of a typical PF resin. It was found that the particle size of lignin affects the performance of the resins, while lignin-based PF resins are suitable for the production of plywood panels and have somewhat better performance relative to fire than typical PF resins. This study has been performed within the framework of the European project BIOCORE (biocommodity refinery for biofuels, chemical intermediates, polymers and materials).

Polymers from renewable feedstocks are receiving increasing attention as the awareness about environmental issues derived from petroleum exploitation and waste accumulation is growing. With unsaturated polyester resins being one of the most used classes of polymers worldwide, the utilization of biobased monomers for manufacturing is more relevant than ever. In the present work, succinic acid, one of the most promising biobased building blocks, was incorporated in the structure of the resins in question to increase their biobased content. By reacting with ethylene glycol (EG) or poly(ethylene glycol) and maleic anhydride (MA) at several molar rations, unsaturated polyester resins (UPRs) were prepared. Their synthesis was evaluated by a variety of spectroscopical techniques, and their rheological properties made use of the reactive diluent mandatory for facilitating processing. Thus, in a second stage acrylic acid (AA) was used as cross-linking agent in the present of initiators and accelerators producing thermosetting resins. Differential scanning calorimetry (DSC) was employed to screen the cross-linking procedure, whereas with X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) it was proven that thermosetting resins were prepared. The thermal stability of the cured materials was evaluated by thermogravimetric analysis (TGA).

The aqueous phase resulting from the catalytic pyrolysis (AQcatPy) of biomass has been successfully applied for acidification of urea-formaldehyde (UF) resins. The resins were synthesized at a laboratory scale and characterized by gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The bonding ability of the resins was tested through the preparation of particle boards (PBs). It was found that the UF resins prepared with AQcatPy as acidification medium have a similar performance to typical UF resins, where conventional chemicals like formic acid (FA) or acetic acid (AA) serve for pH adjustments. The new resins give PBs with somewhat improved thickness swelling (TS) values, while all other properties are at the same level.

In the present work, the effective use of polyethylene-grafted maleic anhydride (PE-g-MA) copolymer as a compatibilizer in high-density polyethylene composites containing 10–50 mass% hemp fibers was evaluated through mechanical and thermal properties measurements. The results revealed a significant reinforcement on the tensile strength of the composites as a consequence of the incorporation of the compatibilizer. Less pronounced effects were found on the elongation at break and impact strength of the composites. The notable enhancement of tensile strength on the compatibilized composites was related to the improved adhesion of hemp with the matrix in the presence of PE-g-MA, which was revealed through scanning electron microscopy observations. Furthermore, Fourier transform infrared spectroscopy analyses suggested that covalent bonding occurs between the fibers and the matrix in the highest PE-g-MA concentrations. Differential scanning calorimetry experiments revealed that the presence of compatibilizer increases the crystallinity of the composites. Thermogravimetry studies revealed that for low compatibilizer concentrations the thermal stability of the composites is further reduced, while for the highest concentration, when bonding occurs, it is enhanced. The biodegradation studies of all the composites revealed that the incorporation of compatibilizer enhances the stability of the composites, especially in the higher concentrations, and reduces their final residue.

Conventional composites from wood and synthetic polymers, like particleboards, find many applications in the construction and furniture sector. However, deforestation, global warming, the concern about adequate wood supplies in the long term, countries that have no land suitable for the development of forests, high volumes of unused agricultural wastes, accumulation of nondegradable plastics, and the unceasing interest of the consumers for new products, are some of the reasons that motivate scientists to seek alternative solutions to wood and petrochemical polymers. The most feasible solution so far seems to be the manufacturing of particleboards with materials from renewable resources that are also biodegradable. To this direction, various agricultural wastes, mostly from lignocellulosic crops like hemp, kenaf, jute, etc., but also residues from other cultivations like rye, rice, wheat, as well as grasses, have been successfully used in combination with biodegradable polymers from natural resources like starch, proteins, PLA, etc. for the production of panels like particleboards. Such panels may be used in a plethora of indoor applications like veneer substrates, flooring, cupboards, furniture, and many others. The demand for both particleboards and biodegradable polymers are expected to increase significantly in the forthcoming years and their future market outlook is very promising.

In the present work urea–formaldehyde resins (UF) containing different amounts of SiO2 nanoparticles were synthesized and studied in depth. All the hybrids were characterized with Fourier transform infrared spectroscopy (FTIR) and powder X-ray diffractometry (XRD), while the dispersion of nanoparticles was studied with scanning electron microscopy with associated energy dispersive X-ray spectrometer (SEM/EDS). It was found that even though silanol groups of SiO2 can interact with UF resin and form hydrogen bonds, aggregates of SiO2 nanoparticles can still be formed in UF resin. Their size increases as SiO2 content is increased. The curing reactions were examined with differential scanning calorimetry (DSC) and it was revealed that curing temperature of UF resin is slightly affected by the addition of nanoparticles. Furthermore, the activation energy of the curing reactions, for every hybrid, was calculated using the Kissinger's method, which implied the existence of interactions between the nanoparticles and the polymer chain. Thermogravimetric analysis (TGA) revealed that SiO2 nanoparticles do not have an effect in the thermal stability of the resin. From the application of the prepared UF/SiO2 resins in wood panels it was found that the mechanical properties of the panels, like the internal bond and the modulus of rapture, are enhanced with increasing nanoSiO2 concentration.

Urea-formaldehyde (UF) resins are the most used polycondensation resins today, in manufacturing particleboards. UF resins possess some advantages such as fast curing, good performance in the panel, water solubility and low price. However, the main chemical bonds of the UF resins macromolecules are hydrolysis sensitive. This causes low water and mositure resistance performance and subsequent formaldehyde release from the UF-bonded panels. A multitude of pathways have been explored for the improvement of UF resins’ behavior relating either to their synthesis procedure or application parameters during panel manufacture. In this study, two UF resins (a conventional and an innovative one produced at very low pH and temperature conditions) were analyzed for their specifications and characterized with TG-DTA technique in dynamic heating conditions and FTIR measurements both in their pre-polymer and cured state.

Left ventricular (LV) remodeling after acute myocardial infarction (AMI) is related to increased morbidity and mortality. The aim of the present study was to examine whether LV deformational and torsional parameters can predict LV remodeling in patients with AMI.Forty-two patients (age 57 ± 14 years) presenting with an anterior ST-elevation AMI and treated with primary percutaneous transluminal coronary angioplasty (PTCA) were included in the study. Four days post MI, LV ejection fraction (EF), LV torsion, longitudinal (4-, 3-2-chamber) and circumferential strain of the LV apex were evaluated by conventional and speckle-tracking echocardiography. The echocardiographic study was repeated at 3 months post-AMI and patients with LV remodeling, i.e. an increase15% in LV end-systolic volume (LVESV), were identified.The 13 patients with LV remodeling had significantly more impaired apical circumferential strain (-7.3 ± 2.2% vs. -18.9 ± 5.2%, p=0.001), EF (42 ± 7% vs. 48.9 ± 6%, p=0.005), LV apical rotation (6.8 ± 4.8° vs. 11.1 ± 4.0°, p=0.027), and LV global longitudinal strain (-9.7 ± 1.9% vs. -12.9 ± 2.9%, p=0.03) on the 4th day post-AMI, in comparison to those without LV remodeling. Apical circumferential strain on the 4th day post-AMI showed the strongest correlation with the LVESV 3 months post-AMI (r=0.76, p=0.001), compared to EF (r=-0.60, p=0.001), global longitudinal strain (r=0.56, p=0.001), and LV apical rotation (r=-0.53, p=0.001). Furthermore, apical circumferential strain demonstrated the highest diagnostic accuracy: area under the receiver operating characteristic (ROC) curve 0.98, with sensitivity 100% and specificity 96% for prediction of LV remodeling, using a cutoff value-11.0%.In patients with anterior AMI, LV apical circumferential strain in the early post-MI period constitutes a significant prognostic factor for LV remodeling at 3 months. Assessment of this parameter may identify patients at high risk for heart failure development.

The aim of this study was to investigate the effect of coronary flow (CF) changes and inflammatory indices on myocardial microcirculation--assessed by myocardial contrast echocardiography (MCE)--and on left ventricular remodelling, in an experimental ischaemia-reperfusion model.In 15 pigs, weighing 30 +/- 5 kg, ligation of the left anterior descending (LAD) coronary artery was performed, followed by reperfusion for 120 min. Peak, mean, duration and volume of systolic and diastolic components of CF distal to the LAD ligation were measured using a butterfly flowmeter and their ratio was calculated. The following two-dimensional echocardiography indices of LV geometry/function were measured from the apical four-chamber view: LV end-systolic (ESD) and end-diastolic (EDD) dimension long- (Ls, Ld) and short-axis (Ss, Sd) and their ratio (Ld/Sd, Ls/Ss, defined as the sphericity index). Interleukin (IL) 1beta, 6, 10 and tumour necrosis factor (TNF) were measured in samples obtained from the LV cavity and coronary sinus. A 0.5 ml/min injection slow bolus over 30 s of SonoVue was made into the left ventricle (LV) in order to assess myocardial perfusion by MCE. Standard apical four-chamber views were digitally acquired and stored for off-line analysis using the Echofit system. The peak intensity (Ac) of the microbubbles at the apex, distally to ligation, was normalised with respect to the peak intensity of the microbubbles in the LV cavity. All parameters were recorded at baseline, immediately after ligation and at 5, 15, 30, 60, 120 min during reperfusion. The percentage changes of CF indices, echocardiographic parameters, interleukins and Ac between baseline and reperfusion were calculated.Mean systolic CF, systolic volume, peak and mean diastolic flow (MDF) changes and epicardial mean CF, Ld/Sd, Ls/Ss changes and coronary sinus IL-6 (IL-6 cs) were inversely correlated with Ac changes during reperfusion. At 5 and 15 min of reperfusion (hyperaemic phase), the greatest median increase of mean diastolic (172% and 86%), and mean systolic CF (713% and 344%) and the greatest reduction of Ac (-41% at 5 min) compared to baseline (P0.05) were observed. The maximum increase of IL-6 cs (40%) was detected at 120 min. ROC analysis showed that of all examined echocardiography indices an increase of mean diastolic CF22% was the best predictor of a25% reduction of Ac with 76% sensitivity and 65% specificity (area 71%, CI 54%-85%, P = 0.02). In addition an32% increase of IL-6 at 120 min of reperfusion predicted a25% reduction of Ac with a 76% sensitivity and 65% specificity (area 71% CI 61%-97%, P = 0.01).Changes of mean diastolic CF and IL-6 cs are associated with alterations in myocardial microvascular integrity after ischaemia-reperfusion and may be used as a predictor of myocardial dysfunction.