Poly(vinyl chloride)-supported triazoles grafted onto calix[4]arene for chromium ions extraction

A new suitable material was synthesized using click reaction between dialkynyl-p-tert-butylcalix[4]arene and poly(vinyl chloride) azide (PVC-N3). This novel dialkynyl-p-tert-butylcalix[4]arene with triazole groups grafted onto PVC polymer (PVC-0.75CX[4]) has an excellent extraction capability for chromium ions from aqueous solutions. It shows a unique ability to extract chromium (VI) ions from aqueous solutions, thanks to the soft cavity, the presence of π-triazole rings and hydrogen bonds. Cr (VI) ion sorption capacity is 95.5% at pH = 3.

Determination of moxifloxacin hydrochloride in AVELOX pharmacological formulations using modified potentiometer sensors

Three different carbon paste (CP), silk-screen (SP) and poly (vinyl chloride) (PVC) modified electrodes were obtained to verify the reliability of AVELOX, the generic name of which is Moxifloxacin HCl (AV-MOXH). The sensing membranes were containing AVELOX ion associated complexes with sodium tetraphenylborate (NaTPB), phosphomolybdic acid (PMA), phosphotungstic acid (PTA), and ammonium reineckate (RN) as electroactive materials. All three electrodes gave fast, viable, and near-Nernstian linear responses over a relative wide concentration range that ranged from 1.010-6 to 1.010-2 mol / L AV-MOXH at 25° C with a monovalent cationic decrease. The sensors demonstrated a good discernment of AV-MOXH from numerous inorganic and organic compounds such as glucose, sucrose, Na+, Ca+, etc. Additionally, the isothermal coefficients along with selectivity coefficients were calculated. The modified Screen Printed Electrode sensor appeared to be highly sensitive for the determination of AV-MOXH. The electrode response was observed in pH range 2--6 for ISPE electrodes and IPVC electrodes and 3--7 for ICPE electrodes under various temperature conditions. The short response time, lifetime validity, recovery, and all the methods of validation such as limit of detection and limit of quantification were estimated. The potentiometric method turned out to be suitable for determining AV-MOXH in pharmacological formulations, and the findings obtained are comparable to the “HPLC official method” in terms of the agreement. As a result, the postulated potentiometric approach was verified in accordance with IUPAC guidelines.

The new functional filler TiO2-SiO2/polyhedral oligomeric hybrid silsesquioxane as a potential modifier of polyethylene

The paper presents preliminary application studies of the innovative TiO2-SiO2/ POSS filler as a potential low-density polyethylene modifier. It was found that the addition of the filler increases the stiffness and hardness of the composite and slightly changes the intensity of its color.

Synthesis of polymer-grafted gold nanoparticles via gamma radiation

The research focused on the synthesis of poly(tetrafluoroethylene) (PTFE) grafted with gold nanoparticles (AuNP). The Turkevich method, one of the common techniques of AuNP synthesis, was used to obtain an AuNP solution with a nanoparticle size of 20 nm. The PTFE-AuNP samples were subsequently irradiated and the absorbed doses were 0.5, 2, 5, 10 and 20 kGy. It was noticed that samples irradiated with 0.5 and 2 kGy were less stable and less concentrated than samples irradiated with higher doses due to aggregation and formation of precipitation after 30 days.

Synthesis of polymer-grafted gold nanoparticles via gamma radiation

The research focused on the synthesis of poly(tetrafluoroethylene) (PTFE) grafted with gold nanoparticles (AuNP). The Turkevich method, one of the common techniques of AuNP synthesis, was used to obtain an AuNP solution with a nanoparticle size of 20 nm. The PTFE-AuNP samples were subsequently irradiated and the absorbed doses were 0.5, 2, 5, 10 and 20 kGy. It was noticed that samples irradiated with 0.5 and 2 kGy were less stable and less concentrated than samples irradiated with higher doses due to aggregation and formation of precipitation after 30 days.

Pineapple leaf fibers as a reinforcement of biocomposites - an overview

Based on 87 references, a literature review was presented on PLA reinforced with pineapple leaf fibers (PALF). The properties of PALF were compared with those of other natural fibers. Mechanical properties of PLA composites and factors influencing them, such as filler content, adhesion at the interface between polymer fiber and matrix, as well as fiber length and their modification were discussed. Potential applications of PLA/PALF composites were also presented.

Influence of molecular weight on dielectric properties and piezoelectric constant of poly(vinylidene fluoride) membranes obtained by electrospinning

A significant influence of the molecular weight on the dielectric properties and piezoelectric constant of poly(vinylidene fluoride) (PVDF) membranes obtained by electrospinning was demonstrated. Electrochemical impedance spectroscopy and d33 meter were used to evaluate dielectric properties and piezoelectric constant respectively. The presence of the β-phase was determined by Fourier transform infrared spectroscopy (FTIR) and X-Ray diffraction (XRD). The membranes with the lowest molecular weight (180,000 g/mol) possessed the best dielectric properties. They also had the highest piezoelectric constant (21 pC/N) and dielectric constant (2.9 at 50 Hz) as well as the highest β-phase content (80.25%).

Influence of weather conditions on the durability of acrylic-polyurethane car coatings in an industrial area

The influence of weather conditions on the durability of acrylic-polyurethane car coatings during their exposure to industrial plants (Grupa Azoty, Zakłady Chemiczne "Police" SA) was investigated. The surface structure and the general appearance of the paint coatings (after 16 months of the test) were examined using an optical microscope and a scanning electron microscope, an optical profilometer and a gloss meter. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) were used to study the composition and chemical structure of the coatings. Convex spots of various sizes were observed on the surface of the tested coatings. Quantitative profilometric analysis showed a clear increase in surface roughness. However, the results of the XPS and FTIR tests did not confirm the chemical degradation of the tested samples. It was shown that the convexities observed on the surfaces of the aged coatings were atmospheric deposits consisting mainly of oxygen, calcium, phosphorus, iron, silicon and carbon. Thorough cleaning of the surfaces resulted in their complete removal.

Nanogels obtained by gamma radiation induced polymerization

The influence of 2-(dimethylamino)ethyl methacrylate (DMAEMA) concentration on the temperature sensitivity of nanogels based on N-isopropylacrylamide (NIPAAM), poly(vinylpyrrolidone) (PVP), poly(ethylene glycol) diacrylate (PEGDA) by gamma radiation induced polymerization was investigated. Dynamic light scattering (DLS) and zeta potential measurements were used to characterize the nanogels. Temperature has been found to cause the nanogel particles to swell and shirnkage, allowing controlled dosing of the drug contained in capsules. The developed nanogels are promising materials with great potential for biomedical applications.

Synthesis and applications of calcium-aluminum layered double hydroxides - an overview

The synthesis and application of layered calcium-aluminum double hydroxides (Ca-Al LDHs) for the encapsulation of organic anions is discussed. The mechanism of the encapsulation process was explained. These types of compounds have great potential and can be used in targeted therapies, including in drug dosing systems.