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Fluorescence and colorimetric solid sensors for caustic media and biogenic amine vapors have been prepared. For this purpose, several hydrazone derivatives of naphthalimides were synthesized and anchored to a photo-crosslinked membrane functionalized with acid chloride groups. The membranes were characterized using different techniques, and their thermal properties and swelling degree were determined. The new naphthalimides and the membranes were evaluated as sensors by determining the change in their spectroscopic properties of absorption and fluorescence with pH. The polymeric sensors exhibit improved stability and can be reused, as a consequence of their solid character and the reversibility of the process. Furthermore, membranes were evaluated as a sensor of trimethylamine vapors through their absorption and fluorescence bands, and the color change in the membrane showed that it could be used to detect basic media with the naked eye. Finally, membranes were packaged in Petri dishes at a controlled temperature with fresh fish bought in the local market. Then, the real chance of using the sensory materials was determined by analyzing the color change in samples.

Novel water-swollen photo-crosslinked membranes were obtained by copolymerization of the N-vinylpyrrolidone, butyl acrylate and ethyl methacrylate monomers functionalized with naphthalimide groups, as pH sensitive fluorescence probes. For that purpose, two monomers with pending naphthalimide groups anchored to ethyl methacrylate through alkyl chains with different length, were previously synthesized. The membranes were characterized using different techniques. The pH dependence of absorbance and the corresponding quenching of fluorescence were investigated and related to the structure of naphthalimide substituents linked to the membrane. The new solid sensors exhibited sensitive fluorescence changes at pH < 3, and lower time response was determined for membranes where the sensing group was linked through longer alkyl chain to the polymer matrix. The membranes were solid, thermally stable and easily handled to be applied as sensor materials, and showed a reversible behavior, which is an important feature for further fabrication of an economical on-site tool for the acidity detection in aqueous environments.

In this study, new blends of PCL/PEC have been prepared in an easy manner by casting with the objective of obtaining new biomaterials to apply to tissue engineering and bone regeneration. The PCL/PEC blends obtained, together with neat polymer blends, were characterized by infrared spectroscopy (FTIR), atomic force microscopy (AFM), scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). This full characterization is the key to disentangle the miscibility, which means good compatibility, of the polymer blends used in this work. The addition of increasing amounts of PEC, has shown in the new biomaterials obtained, a remarkable improvement in relation with the mechanical properties (manageable materials) and above all, in terms of an increase in their hydrophilic character with respect to the PCL neat polymer. The improvement of all these properties is reflected in their biological properties. With these thoughts in mind, the blends obtained were tested through the assessment of several biological parameters such as cell viability, proliferation, and differentiation of both the MC3T3-E1 osteoblastic cell line and hMSCs to evaluate their cell response to different polymer membranes aimed at bone tissue regeneration. “In vitro” biocompatibility methods have been chosen rather than in vivo studies due to their lower cost, faster procedure time, and minimum ethical concerns, and because it was the first time that the biological effects of these blends were studied. The results show that the PCL/PEC blends obtained, with tunable properties in terms of hydrophilic character and hydrolytic degradation, may be regarded as good candidates to perform “in vivo” tests and check their real-life applicability for bone regeneration. The polymer acronym (the weight percentage in the sub index) is PCLx/PECy as noted in table one with the summary of compositions.

Novel fluorescent solid sensors for Fe detection in aqueous medium have been developed by photopolymerization of N-vinylpyrrolidone (VP), butyl acrylate (BA) and imidazolium-based ionic liquids obtained by anion change (Br, BF, TFSI and PF). The correlation between the hydrophilicity and the stability of the membranes was established, as well as the influence of the anion in their behavior. The resulting fluorescent sensors undergo fluorescence quenching upon binding iron ions. This study provides a convenient method to obtain PILs sensors easy to use and reusable, with high selectivity and sensitivity.

A range of prepared titania nanoparticles were characterised by Brunauer-Emmett-Teller (BET) surface area, X-ray Diffraction (XRD), CPS Disc Centrifuge, Transmission Electron Microscope (TEM), Scanning Electron Micrographs (SEM), Thermogravimetric Analysis (TGA) and Fourier Transform Infrared Measurements (DRIFTS). In addition, the activities of the different catalysts were determined via rapid assessment methodologies like Microwave Dielectric Spectroscopy (MDS), Hydroxyl content, Phosphorescence and Chemiluminescence Spectroscopy and Isopropanol Oxidation Test and the data related to actual weathering properties of the pigments doped in metallocene polyethylene under dry and humid conditions. Quantum size effects, which lead to high surface areas and blue shifts and diminish electron–hole recombination, are used to explain the high activities of the nanoparticle products. In situ FTIR data and OH content determination show the presence of high contents of hydroxyl groups and large amounts of adsorbed water on TiO nanoparticles. The Disc Centrifuge results and BET surface area combined with the XRD particle size results show that a careful distinction between the crystal and aggregate sizes must be made in order to properly interpret the activity of TiO pigments. Aggregation of TiO pigments affects not only the surface area offered by the TiO but also the type of interaction between the light and the TiO. The treatment conditions used for the crystallization of the primary material (precursor) in order to prepare the nanoparticle pigments, not only influenced the anatase crystal size but also other anatase properties (such as the surface hydroxylation, adsorbed water, recombination rate, aggregation state and type of structural defects). Chemiluminescence of the titania particles is discussed in light of potential surface active peroxidic species.

Two commercial mulching films based on aliphatic–aromatic copolyesters, poly(butylene adipate-co-terephthalate) (PBAT) and its blend with poly(lactic acid) (PBAT/PLA) were selected to study their photodegradation and their biodegradation under thermophile conditions. The films were buried in an agricultural field and bacteria were isolated from these. Bacterial strains were characterized with a combination of culture-dependent methods and sequencing of part of the 16S ribosomal RNA gene (rDNA). The most prevalent genus isolated was Bacillus and other related genera were found as well. Consortia of the isolated indigenous bacterial strains, IDN-EF and IDN-EC, and an additional consortia that had been previously isolated from exposed polyethylene, Bacillus-MIX, were prepared to perform the biodegradation assay at 45 °C on highly photodegraded films. Changes in the films were studied using chemiluminescence, ATR–FTIR, contact angle, SEM, GPC, DSC and TGA. A biodegradation assay was also performed on the four monomers that constitute the polymers using Bacillus subtilis and Bacillus licheniformis. Mineralization was evaluated by carbon dioxide measurements using an indirect impedance technique. This technique showed that overall there was a higher mineralization for the photodegraded materials. However, the biodegradation was most efficient when B. subtilis was present in the bacterial consortium and especially when the materials had been previously photodegraded.

Ion gel polyelectrolytes (IGPs) were prepared by photopolymerization of the synthetic cationic monomers: 1-(2-methacryloyloxy)ethyl-3-butylimidazolium bis(trifluoromethane sulfonyl)imide (IMMATFSI)/bisfluorosulfonylimide (IMMAFSI) or 1-(2-methacryloyloxy)ethyl-1-methylpyrrolidinium bisfluorosulfonylimide (PYRMAFSI)/bis(trifluoromethane sulfonyl)imide (PYRMATFSI) in the presence of bis(trifluoromethane)sulfonamide (LiTFSI) solutions at different concentrations in either 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide (EMIFSI), 1-ethyl-3-methylimidazolium bis(trifluorosulfonyl)imide (EMITFSI) or N-propyl-N-methylpyrrolidinium bis(fluorosulfonyl)imide (PMPFSI). The resulting IGPs are thermally stable, easy-to-handle solids wherein the overall ionic conductivity ranges from about 1 to about 10 mS cm at 25 °C. The diffusivity of the ions Li, FSI and TFSI was studied at 25 °C by PGSE-NMR. In IGPs containing imidazolium groups both in the polycationic scaffold and the ionic liquid phase, their large Li ion diffusivities (up to 40 × 10 m s, well above that of the anions) suggest the existence of an important contribution of anion exchange Li transport. To a lesser extent anion exchange may also be occurring in IGPs containing pyrrolidinium groups in the polycationic scaffold and imidazolium groups in the ionic liquid phase and to an even lesser extent in those IGPs with pyrrolidinium in both the polyelectrolyte and the ionic liquid phase. Because of the dimensional and thermal stabilities of IGPs, safety of their components, and their large Li-ion diffusivity, these types of electrolytes appear as excellent candidates for Li and Li-ion batteries.

A water soluble derivative in 98% yield with 23.1% incorporation of maleoyl groups was obtained by esterification of agarose with maleic anhydride. Graft copolymers were synthesized through vinyl groups of maleoylagarose with N-isopropylacrylamide using ceric ammonium nitrate or ammonium persulfate as initiator, by conventional method or microwave irradiation. High nitrogen content (4.6%) was obtained in the grafting process using ceric ammonium nitrate as initiator without microwave irradiation. Copolymers were characterized by FT-IR and NMR spectroscopies, TGA, DSC and morphological analysis by AFM and SEM microscopy, confirming the grafting of PNIPAAm onto polysaccharide backbone. Hydrogel films were obtained by ionic complexation between opposite charged groups of maleoylagarose-g-poly(N-isopropylacrylamide) and chitosan. The swelling of 1:1 w/v maleoylagarose-g-PNIPAAm:chitosan film was higher than 2:1 w/v film at 25 and 37 °C. 53% release in vitro of diclofenac sodium from 1:1 w/v maleoylagarose-g-PNIPAAm:chitosan was obtained at 37 °C and pH 6.0 with <0.5 diffusional constant values.

A Selective fluorescence solid sensor for Hg detection in aqueous solution (M-MBZN) has been developed by grafting N-(2-hydroxyethyl)-4-(4-(1H-benzo[d]imidazol-2-yl)methyl) piperazine-1-yl)-1,8-naphthalimide (MBZN) to a photo-crosslinked M-Cl membrane reaction through the acid chloride groups. The resulting fluorescence sensor undergoes fluorescence enhancement upon binding mercuric ions which provokes a photo-induced electron transfer (PET) inhibition process from the piperazine to the naphthalimide moiety. Various photochemical parameters were determined by using pH-dependent absorption and fluorescence spectroscopies as well as the selective detection of Hg. The sensing membrane possesses a switchable “turn-on” fluorescence response to Hg in pure water; it is easy to use and reusable and shows high selectivity and sensitivity.

A photocrosslinked membrane (M-Cl) based on vinyl-pyrrolidone/butyl acrylate containing ethylene glycol dimethacrylate as a crosslinking agent and methacryloyl chloride as reactive monomer has been prepared for further functionalization. A series of hydroxy substituted piperazine naphthalimide compounds have been synthetized as pH sensitive Off-On fluorescence probes using two methods: microwave and reflux. Three of the derivatives were selected to be anchored to the M-Cl membrane through the acid chloride groups by the Schotten-Baumann reaction. All the obtained water-swollen membranes were characterized using different techniques. Photo-induced electron transfer (PET) and its pH-dependent optical changes were investigated and various photochemical parameters were determined by using pH-dependent absorption and fluorescence spectroscopies. In the pH range of 9.0–4.0, these solid sensors undergo PET process from the piperazine to the naphthalimide moiety leading to a fluorescence quenching. However, in the pH range of 4.0–1.0, the PET is inhibited to give a fluorescence enhancement. The sensitivity of the functionalized membranes to pH changes depended on the size and position of the naphthalimide substituents.

Several polyethylene resins; high density polyethylene (Ph-HDPE, Phillips metal oxide catalyst) and linear low density polyethytlenes (LLDPE, formed using Ziegler-Natta catalyst and metallocene catalyst technology, m-LLDPE) were used in order to acquire an insight in to the effect of different polymerization catalyst systems on the melt stabilization performance of single AO. Chemiluminescence (CL) and melt flow rate (MFR) were used to analyze the degradation as a function of the number of passes through a twin-screw extruder. A good correlation was obtained, and the additives resulting with the best melt flow stability in the polymer were the same as those that promote the best CL results.

All rights reserved. Coumarin chromophores were successfully bonded onto ethylene-co-butyl acrylate (EBA) with a butyl ester content of 17% under mild conditions in solution via microwave irradiation. The synthesis consisted of three steps: partial conversion of butyl esters into carboxylic acid groups, conversion of carboxylic acid functionalities into acid chloride groups and esterification using 7-(3-hydroxy-propoxy) coumarin. The EBA modified with coumarin groups was characterized using FTIR, NMR, UV spectroscopy and thermal methods. The EBA modified with coumarin moieties (EBA-g-coum) was crosslinked by irradiating at 365 nm, and the coumarin photodimers were cleaved by irradiating at 280 nm. The reversibility of the photoreactions in the solid state was monitored using UV spectroscopy. Additionally, the mechanical properties of the materials were determined.

We have developed silica stabilized ferrimagnetic magnetite nanocubes (MNCs) as effective heat mediators for magnetic hyperthermia. To do that, large hydrophobic magnetite nanoparticles, with a mean size of 79 and 124 nm were synthesized and transferred to water by silica surface modification. The heating ability of these water suspensions was studied by measuring the Specific Power Absorption (SPA) applying an AC magnetic field of amplitude H0 = 45 kA/m and frequency f = 360 kHz. High SPA values were obtained, ranging from 560 to 1160 W/g. The normalization of the SPA values by the inverse of the frequency and squared field amplitude was performed in order to compare our results with these described in literature. The SPA value for our samples, normalized in this way, yielded values of 0.7-1.5 nH m2/kg.