Assessment of the impact of bacteria Pseudomonas denitrificans,Pseudomonas fluorescens,Bacillus subtilis and yeast Yarrowia lipolytica on commercial poly(ether urethanes)

The assessment of the impact of the bacteria Pseudomonas denitrificans, Pseudomonas fluorescens, Bacillus subtilis and yeast Yarrowia lipolytica on commercial poly(ether urethanes) Tecoflex^® and Tecothane^® is presented. The polyurethane samples were incubated with pure cultures of the microorganisms at 30 °C for five months. The changes in the chemical structure of the polymers were evaluated using loss of weight and contact angle measurements, infrared spectroscopy (ATR-FTIR), mass spectrometry (Py-MS), differential scanning calorimetry (DSC) and the thermogravimetric analysis (TG). In addition, scanning electron microscopy (SEM) and atomic force microscopy (AFM) were applied for imaging changes in surface morphology of the poly(ether urethanes). Comparative analysis of these polyurethane features before and after incubation with the microorganism cultures showed that Tecoflex^® was less stable than Tecothane^®. This can be explained by the presence of aromatic rings within the diphenylmethane diisocyanate group in the chemical structure of the latter. Bacterial strains of Bacillus subtilis and Pseudomonas fluorescens showed a much more prominent destructive effect compared to the strain of yeast Y. lipolytica.     

New sights into the electrochemical interface provided by in situ X-ray absorption fine structure and surface X-ray scattering

Various important processes, such as electron transfer reactions, adsorption/desorption, solvation/desolvation, and formation/cleavage of chemical bonds, take place at electrolyte/electrode interfaces during electrocatalytic reactions. Those processes have been understood on the basis of changes in the surface composition, atomic arrangement, and molecular and electronic structures of the interfaces by using various in situ analysis techniques. To date, in situ analysis and observation of those interfacial processes at an ideal single-crystal surface are indispensable not only for fundamental understanding of the reaction mechanism but also for rational design of the highly efficient and durable electrocatalytic materials. Here, historical and recent progress of in situ studies on electrocatalytic reactions is briefly reviewed with a focus on two major techniques, X-ray absorption fine structure and surface X-ray scattering.     

Poly (ethylene-co-vinyl acetate) films prepared by solution blow spinning: Surface characterization and its relation with E. coli adhesion

Solution blow spinning, SBS, a quite novel processing method, was used to obtain poly (ethylene-co-vinyl acetate), EVA, films with controlled surface properties. The influence of the surface characteristics of EVA films on the adhesion of DH5α Escherichia coli was studied. In particular, the initial concentration of the EVA solution to be blow spun was varied in order to get different surface topographies. Considering the potential use of EVA based materials in applications such as food packaging or scaffolds for tissue engineering all factors affecting proliferation of microorganisms on their surfaces should be studied and understood. Structural, morphological and surface characterizations based on the use of infrared spectroscopy, FTIR, scanning electron microscopy, SEM, and contact angle measurements were performed to ascertain the main factor influencing the E. coli adhesion on the EVA films. Roughness data were determined at different scales from 3D surfaces obtained using a stereoscopic reconstruction of SEM images. It was concluded that, depending on the conditions of the SBS process, only variations of topography were found on the EVA films, being therefore the unique cause of different adhesion capacity of E. coli cells. A correlation between roughness and the number of attached E. coli cells showed that the higher the roughness at microscale level the higher the biofilm development, demonstrating that, apart from specific interactions at nanoscale surface, heterogeneity at microscale can greatly modify the antibacterial action.     

Effect of gelatin on micellization and microstructural behavior of amphiphilic amitriptyline hydrochloride drug solution: A detailed study

Herein we have investigated the dealings between amphiphilic antidepressant drug amitriptyline hydrochloride (AMT) and gelatin interaction using different proposed techniques. AMT is used for the treatment of mental/mood problems such as depression. Gelatin interacts with this drug alike fashions to the interaction of polymers and surfactants i.e., critical aggregation concentration (cac) and polymer saturation point (psp) were together achieved significantly. AMT and gelatin interaction starts due to the highly surface active complex formation as disclosed by decreasing of surface tension of gelatin solution by adding of AMT. It was uncovered from results that cac decreases on increasing the gelatin concentrations, whereas psp increases which is a sign of the attraction between AMT and gelatin. Thermodynamic parameters were also evaluated and discussed in detail. Fluorescence measurements were used to find the values of average aggregation numbers (N_agg) and various other parameters like Stern–Volmer constant (K_sv) and micropolarity. The nuclear magnetic resonance (¹H NMR) data suggested that AMT interacts with gelatin by the means of hydrophobic interaction. The ¹H NMR experiments explain that the extent of chemical shifts (δ) and line width (lw) increases with the increase in gelatin concentration. Secondary structure of gelatin was also examined via circular dichroism (CD) technique at different concentration of AMT. CD results confirmed that with increasing drug concentration the random coil portion of gelatin enhances. Field emission scanning electron microscope (FESEM) provided clear pictures of (drug + gelatin) interaction.     

Needleless electrospinning of poly(acrylic acid) superabsorbent: Fabrication,characterization and swelling behavior

In this work, nanofibrous hydrogel has been fabricated from needleless electrospinning of Poly(acrylic acid) (PAA) in an aqueous solution with different concentrations. First, all solution samples were characterized for pH, surface tension, conductivity and viscosity. Next, electrospinnability of the PAA-water dope solution was investigated using the needleless electrospinning technique under constant conditions. Results indicated that the PAA-water solution was not electrospinnable. Therefore, the neutralization of carboxylic groups in the PAA chemical structure using the NaOH solution was investigated to enhance the PAA electrospinnability. Morphology observation revealed that the fiber diameters ranged from 40 to 250 nm and increased with increasing the solution concentrations. Increasing the neutralization degree (10%, 15% and 20% with 50 wt% NaOH solution) led to increase the dope viscosity and conductivity. The resultant nanofibers could be rendered water-insoluble by incorporating 1,4-butanediol diglycidyl-ether in the PAA-water dope solution, then heat-induced crosslinking was performed using a microwave at different curing times (1–5 min) and temperatures (45–105 °C). The nanofibrous hydrogel mat was then characterized by FTIR. The resulting nanofibrous hydrogel showed remarkable water absorption capacity up to 17,000% and 51,000% (within 15 min) in the standard saline solution and distilled water, respectively.     

Effect of post-deposition annealing temperature on RF-sputtered HfO2 thin film for advanced CMOS technology

Structural and electrical properties of HfO₂ gate-dielectric metal-oxide-semiconductor (MOS) capacitors deposited by sputtering are investigated. The HfO₂ high-k thin films have been deposited on p-type <100> silicon wafer using RF-Magnetron sputtering technique. The Ellipsometric, FTIR and AFM characterizations have been done. The thickness of the as deposited film is measured to be 35.38 nm. Post deposition annealing in N₂ ambient is carried out at 350, 550, 750 °C. The chemical bonding and surface morphology of the film is verified using FTIR and AFM respectively. The structural characterization confirmed that the thin film was free of physical defects and root mean square surface roughness decreased as the annealing temperature increased. The smooth surface HfO₂ thin films were used for Al/HfO₂/p-Si MOS structures fabrication. The fabricated Al/HfO₂/p-Si structure had been used for extracting electrical properties such as dielectric constant, EOT, interface trap density and leakage current density through capacitance voltage and current voltage measurements. The interface state density extracted from the G–V measurement using Hill Coleman method. Sample annealed at 750 °C showed the lowest interface trap density (3.48 × 10¹¹ eV⁻¹ cm⁻²), effective oxide charge (1.33 × 10¹² cm⁻²) and low leakage current density (3.39 × 10⁻⁹ A cm⁻²) at 1.5 V.     

A comparative study on the AC/DC conductivity,dielectric and optical properties of polystyrene/graphene nanoplatelets (PS/GNP) and multi-walled carbon nanotube (PS/MWCNT) nanocomposites

Polystyrene/graphene nanoplatelets (PS/GNP) and polystyrene/multi-walled carbon nanotube (PS/MWCNT) nanocomposites were prepared through solution mixing processing. The effect of carbon filler (CF) (GNP or MWCNT) doping on the DC/AC electrical conductivity, dielectric characteristics and optical parameters (absorption coefficient, α and band gap energy, E_g) of nanocomposites were investigated and compared for similar doping concentrations. The observed behavior of the DC surface conductivity for PS/CF nanocomposites was explained according to the classical percolation theory, where the percolation thresholds (ϕ_c) for PS/GNP and PS/MWCNT nanocomposites were determined as 12.0 vol% and 3.81 vol% and the critical exponents (t) were calculated as 2.19 and 2.13, respectively. These results indicate that CFs create three dimensional CF network in PS matrix. The dielectric relaxation properties and the AC conductivity studied by means of Broadband Dielectric Spectroscopy (BDS) measurements, showed that the presence of carbon fillers significantly enhanced the capacitive/charge storage capabilities of the nanocomposites. The optical band gap energies (E_g) of PS/GNP and PS/MWCNT nanocomposites were obtained by using Tauc method. From applicative point of view, with their enhanced dielectric and AC conductivity properties of the PS/GNP and PS/MWCNT nanocomposites have the potential to be used in energy storage and electromagnetic interference (EMI) shielding applications.     

Structural and mechanical studies on modified reused tyres composites

Reused tyres powder was used as reinforcement in HDPE-reused tyre composites. In order to improve the compatibility between both components, several pre-treatments performed over the rubber tyres were applied: sulphuric acid etching, use of a silane coupling agent and chlorination with trichloroisocyanuric acid (TCI). Mechanical properties of the resulting materials (e.g. tensile strength, Young’s Modulus, toughness and elongation at break) were studied and compared. Chemical modifications on the surface of reused tyres were monitored by FTIR and physical modifications and behaviour to fracture were followed by means of SEM. The influence of rubber pre-treatment was assessed by comparing the results of treated and untreated composites with those for neat HDPE. Reused tyre rubber, added to the HDPE in small quantities, acts as a filler, improving the stiffness and providing a more brittle behaviour. Pre-treatment with TCI gave poor results in terms of mechanical properties obtaining lower values than neat HDPE in some cases and always worst properties than sulphuric or silane coupling agent. Treatments with H₂SO₄ and silane coupling agent improve the ability of rubber to interact with the HDPE, increasing the material’s stiffness and its tensile strength. Sulphuric acid modificates chemical and physically the particles’ surface improving mainly mechanical adhesion, whereas silane acts as a compatibilizer developing chemical matrix-reinforcement interactions.     

Antimicrobial activities of polyethylene glycol and citric acid coated graphene oxide-NPs synthesized via Hummer’s method

Graphene oxide (GO)-NPs possess excellent physicochemical and biological properties and could have prominent antimicrobial activities. We used solution-based Hummer’s method to synthesize pure, CA coated and PEG coated GO-NPs and the XRD revealed hexagonal lattice structure and the crystallite size of pure and coated GO-NPs calculated in the range of 7–16 nm. In addition, a spongy like surface in pure GO-NPs and randomly crumpled like surface by using the CA and PEG coating agents was also identified and SEM images irregular, non-uniform and rod shape morphology of the graphite powder. The GO in the UV region and the band gap decreased from 2.30 to 2.03 eV while different modes (CC and CO) on the surface of pure and coated GO-NPs were evident as indicated by Raman spectra. Finally, in-vitro antimicrobial activity was assessed against two-gram negative bacterial strains viz. A. hydrophilaand E. coli and one fungal stain F. avenaceum at 10 and 20 mg/mL concentrations. Our results indicated enhancement in the inhibition zones of pure GO-NPs from 8 to 17 mm, PEG coated GO-NPs from 8 to 20 mm and CA coated GO-NPs from 8 to 17 mm respectively. Overall the PEG coated GO-NPs had prominent antimicrobial activities and we recommend application of polymer coated GO-NPs for wound healing process.     

Determination of dissociation constants for coordination compounds of Cr(III) and Co(III) using potentiometric and spectrophotometric methods

The acid–base properties of analogous complex ions of chromium(III) and cobalt(III) in aqueous solution have been studied. The equilibrium constants for all metal complexes were determined by using potentiometric and spectrophotometric titration methods. First, dissociation constants for the studied complexes of Cr(III) and Co(III) were determined by means of the potentiometric titration method and using the STOICHIO computer programme. Then, pH-spectrophotometric titrations were performed and the OriginPro 7.5 computer programme was used to calculate the same constants. The measurements using both methods were carried out under the same conditions of temperature, T = 298.15 K, and over the same pH range 2.00–10.00, respectively. It turned out that the two methods used enabled us to obtain acidity constants in very good agreement.     

Multiparametric optimization of a new high-sensitive and disposable mercury (II) electrochemical sensor

An electrochemical sensor for mercury (II) determination was developed by modifying the surface of a commercial screen-printed carbon electrode (SPCE) with a polystyrene sulfonate-NiO-carbon nanopowder composite material. Mercury measurements were performed by differential pulse anodic stripping voltammetry (DPASV). Sensor composition and measurement conditions were optimized using a multivariate experiment design. A screening experiment by using a Plackett-Burman design was first performed in order to determine the main contributing factors to the electrochemical response. The most important factors were employed to establish the interactions between different experimental variables and get the best conditions for mercury determination. For this purpose, a five level central composite design and a response surface methodology were used. The optimized method using the developed NiO-PSS-SPCE sensor presents a very low limit of detection of 0.021 μg L⁻¹ and a linear response over two concentration ranges with two different slopes, from 0.05 to 2.0 μg L⁻¹ and between 2.0 and 75 μg L⁻¹. The sensor was successfully applied to mercury determination in water samples.     

Swift heavy ion induced modification in dielectric and microhardness properties of polymer composites

Polymer composites with different concentrations of organometallics (ferric oxalate) dispersed PMMA were prepared. PMMA was synthesized by solution polymerization technique. These films were irradiated with 120 MeV Ni¹⁰⁺ ions in the fluence range 10¹¹-5 × 10¹² ions/cm². The radiation induced modifications in dielectric properties, microhardness, structural changes and surface morphology of polymer composite films have been investigated at different concentrations of filler and ion-fluences. It was observed that electrical conductivity and hardness of the films increase with the concentration of the filler and also with the fluence. The dielectric constant (?) obeys the Universal law given by ?αfⁿ⁻¹. The dielectric constant/loss is observed to change significantly due to irradiation. This suggests that ion beam irradiation promotes the metal to polymer bonding and convert polymeric structure into hydrogen depleted carbon network. This makes the composites more conductive and harder. Surface morphology of the films has been studied using atomic force microscopy (AFM) and scanning electron microscopy (SEM). The average surface roughness is observed to increase after irradiation as revealed by AFM studies. The SEM images show the blisters type of phenomenon on the surface due to ion beam irradiation.     

Influence of electron beam irradiation on physicochemical properties of poly(trimethylene carbonate)

Electron beam (EB) irradiation of poly(trimethylene carbonate) (PTMC), an amorphous, biodegradable polymer used in the field of biomaterials, results in predominant cross-linking and finally in the formation of gel fraction, thus enabling modification of physicochemical properties of this material without significant changes in its chemical structure. PTMC films (M_w: 167-553 kg mol⁻¹) were irradiated with different doses using an electron accelerator. Irradiation with a standard sterilization dose of 25 kGy caused neither significant changes in the chemical composition of the polymer nor significant deterioration of its mechanical properties. Changes in viscosity-, number-, weight-, and z-average molecular weights of PTMC for doses lower than the gelation dose (D_g) as well as gel-sol analysis and swelling tests for doses above D_g indicate domination of cross-linking over degradation. EB irradiation can be considered as an effective tool for increasing the average molecular weight of PTMC and sterilization of PTMC-based biomaterials.     

An inorganic-organic hybrid material from the co-intercalation of a cationic surfactant and thiourea within montmorillonite layers: application to the sensitive stripping voltammetric detection of Pb2+ and Cd2+ ions

A smectite-based inorganic-organic hybrid material was prepared by a one-step intercalation of cetyltrimethylammonium ions and thiourea within the interlayer space of montmorillonite (MT). The surface and textural properties of the resulting material were examined using several techniques (X-ray diffraction, elementary analysis and N₂ adsorption-desorption experiments (BET method)) that demonstrated the presence of both modifiers in the clay mineral structure. The presence of thiourea molecules in the modified MT greatly improved its ability towards the fixation of Pb²⁺ and Cd²⁺ ions when the organoclay material was used for sensing purposes as a glassy carbon electrode modifier. The electro-analytical procedure was based on the chemical accumulation of both analytes under open-circuit conditions, followed by the detection of the preconcentrated species using square wave voltammetry. Upon optimization of different parameters likely to influence the electrode response, linear calibration graphs were obtained in the concentration ranges from 0.1 to 1 μM and 0.01 to 0.1 μM for Cd²⁺ and Pb²⁺, respectively, leading to low limits of detection (4.2 × 10⁻¹⁰ M for Pb²⁺and 1.2 × 10⁻⁹ M for Cd²⁺).     

Potential of atmospheric pressure chemical ionization source in gas chromatography tandem mass spectrometry for the screening of urinary exogenous androgenic anabolic steroids

The atmospheric pressure chemical ionization (APCI) source for gas chromatography-mass spectrometry analysis has been evaluated for the screening of 16 exogenous androgenic anabolic steroids (AAS) in urine. The sample treatment is based on the strategy currently applied in doping control laboratories i.e. enzymatic hydrolysis, liquid–liquid extraction (LLE) and derivatization to form the trimethylsilyl ether-trimethylsilyl enol ether (TMS) derivatives. These TMS derivatives are then analyzed by gas chromatography tandem mass spectrometry using a triple quadrupole instrument (GC-QqQ MS/MS) under selected reaction monitoring (SRM) mode. The APCI promotes soft ionization with very little fragmentation resulting, in most cases, in abundant [M + H]⁺ or [M + H-2TMSOH]⁺ ions, which can be chosen as precursor ions for the SRM transitions, improving in this way the selectivity and sensitivity of the method. Specificity of the transitions is also of great relevance, as the presence of endogenous compounds can affect the measurements when using the most abundant ions. The method has been qualitatively validated by spiking six different urine samples at two concentration levels each. Precision was generally satisfactory with RSD values below 25 and 15% at the low and high concentration level, respectively. Most the limits of detection (LOD) were below 0.5 ng mL⁻¹. Validation results were compared with the commonly used method based on the electron ionization (EI) source. EI analysis was found to be slightly more repeatable whereas lower LODs were found for APCI. In addition, the applicability of the developed method has been tested in samples collected after the administration of 4-chloromethandienone. The highest sensitivity of the APCI method for this compound, allowed to increase the period in which its administration can be detected.     

Modification of microstructure of the surface and the bulk in ion-irradiated membrane studied using positron annihilation spectroscopy

The effect of ion irradiation and etching on the microstructure of polyethyleneterephthalate (PET) membrane has been studied using positron annihilation spectroscopy. PET membrane of 25 μm thickness was irradiated by 100 MeV ³⁵Cl beam (7×10⁷ ions/cm²) and then etched with NaOH for 45 min. The modification in the microstructure at the surface of the membrane was probed by depth-dependent Doppler-broadened S-parameter and positronium 3γ–2γ annihilation ratio using a slow positron beam, while the free volume properties in the bulk of the membrane were studied using the conventional positron lifetime technique. Positron annihilation parameters were found to be very sensitive to the microstructural changes occurring in the polymer at such a low fluence. It was observed that on ion-irradiation, the surface of the membrane is modified in a different way than the bulk. While the ion-irradiation produces large fraction of excess free volumes at the surface of the membrane due to chain scission, the free volumes are reduced in the bulk of the membrane due to cross-linking. FTIR and XRD measurements were also carried out to investigate the changes occurring in the chemical structure and crystallinity of the polymer samples on ion-irradiation and etching.     

Modification of poly(propylene carbonate) with chain extender ADR-4368 to improve its thermal,barrier, and mechanical properties

Melt blending with the application of epoxy compound ADR-4368 as a chain extender was used to chemically modify polypropylene carbonate (PPC). ¹H nuclear magnetic resonance spectroscopy (¹H NMR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and tests using a universal material testing machine, a gas permeability tester, a water vapor permeability tester and other instruments were used to assess changes in the chemical structure, thermal and mechanical properties, and barrier efficacy of PPC before and after modification.The epoxy group in ADR-4368 reacted with the terminal hydroxyl group in PPC, considerably enhancing its mechanical properties, thermal stability and barrier efficacy to O₂ and CO₂. With the addition of 1% ADR-4368, the glass transition temperature of PPC was increased from 17 °C to 26.9 °C, while the thermal decomposition temperature (T_−5%) of PPC was increased from 177.3 °C to 240.6 °C. Moreover, the tensile strength of the modified PPC was improved from 3.3 MPa to 20.7 MPa.     

Novel conducting poly(3,4-ethylenedioxythiophene) – Graphene nanocomposites with gigantic dielectric properties and narrow optical energy band gap

Novel nanocomposites, consisting of conducting poly(3,4-ethylenedioxythiophene) [PEDOT] and graphene nanoplatelets [GNPs], were successfully synthesized by in-situ chemical-oxidative polymerization of 3,4-ethylenedioxythiophene [EDOT] using ammonium peroxydisulfate as an oxidizing agent. The formation of PEDOT and its incorporation onto the surface of GNPs were confirmed by scanning electron microscopy, Fourier-transform infrared-spectroscopy, and X-ray diffraction. The optical energy band gap, E_g^opt, was determined by UV–Vis spectroscopy. Dielectric constant and loss as well as AC electrical conductivity, σ_AC, were determined in the frequency range from 10 Hz to 8 MHz. The PEDOT-GNP nanocomposites were found to have extremely large dielectric constant, ε′, significantly high σ_AC, and narrow E_g^opt values. In particular, PEDOT-GNP nanocomposite with 10 wt% GNP has a gigantic dielectric constant of the order of 9 × 10⁵ at 1 kHz and a narrow optical energy band gap of 1.26 eV. The ε′ values (10⁸ to 10⁵ in the frequency range from 10 Hz to 5 MHz) of PEDOT-10 wt% GNP are the highest among those reported in the literature for carbon based polymer nanocomposites. The massive quantity of micro-capacitors formed in the nanocomposites, prior to the creation of conductive networks, leads to the gigantic dielectric properties. The ε′ and σ_AC values of PEDOT-10 wt% GNP nanocomposite were about 90 and 400 times larger than those of pure PEDOT. Our method should be particularly promising in the development of new materials for high energy storage applications.     

Isothermal (vapour + liquid) equilibrium and thermophysical properties for (1-butyl-3-methylimidazolium iodide + 1-butanol) binary system

Experimental isothermal (vapour + liquid) equilibrium (VLE) data are reported for the binary mixture containing 1-butyl-3-methylimidazolium iodide ([bmim]I) + 1-butanol at three temperatures: (353.15, 363.15, and 373.15) K, in the range of 0 to 0.22 liquid mole fraction of [bmim]I. Additionally, refractive index measurements have been performed at three temperatures: (293.15, 298.15 and 308.15) K in the whole composition range. Densities, excess molar volumes, surface tensions and surface tension deviations of the binary mixture were predicted by Lorenz–Lorentz (n_D-ρ) mixing rule. Dielectric permittivities and their deviations were evaluated by known equations. (Vapour + liquid) equilibrium data were correlated with Wilson thermodynamic model while refractive index data with the 3-parameters Redlich–Kister equation by means of maximum likelihood method. For the VLE data, the real vapour phase behaviour by virial equation of state was considered. The studied mixture presents S-shaped abatement from the ideality. Refractive index deviations, surface tension deviations and dielectric permittivity deviations are positive, while excess molar volumes are negative at all temperatures and on whole composition range. The VLE data may be used in separation processes design, and the thermophysical properties as key parameters in specific applications.     

Synthesis and hydrolytic degradation of poly(ethylene succinate) and poly(ethylene terephthalate) copolymers

The conditions of synthesis of statistical poly(ethylene succinate-co-terephthalate) copolymers (2GTS) and high molecular weight poly(ethylene succinate) (PES) with good hydrolytic and optical parameters, designed for the production of biodegradable products and resins, are presented in this article. Copolymers were prepared by melt polycondensation of bis-(β-hydroxyethylene terephthalate) (BHET) and succinic acid (SA) with excess of ethylene glycol (2G) in the presence of a novel titanium/silicate catalyst (C-94) and catalytic grade of germanium dioxide (GeO₂) as cocatalyst. The chemical structure and physical properties of those materials were characterized by ¹H NMR, FT-IR, dynamical-mechanical thermal analyses (DMTA), differential scanning calorimetry (DSC), solution viscosity and spectroscopic methods. The hydrolytic degradation was performed in a water solution with variable pH, also in garden soil and in compost. The highest hydrolytic degradation rate was observed for pH 4 and for compost. Better hydrolytic degradation values in compost medium were observed for copolyester prepared in the presence of GeO₂ as polycondensation cocatalyst. The copolyester with 40 mol% of aliphatic units was chosen for industrial syntheses which were performed in ELANA and subsequently the processing parameters and compatibility with potato starch of this polyester were checked by BIOP Biopolymer Technologies AG.