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Five commercial products, based on acrylic polymers, have been used for cotton coating. The structures of the polymers have been established based on their IR spectra of the active compound from the acrylic dispersion. The properties of the coated materials have been discussed in connection with the structure of the acrylic polymer.

New poly(succinimide-ether)s with maleimidic rings in the side chain were synthesized by a chemical modification reaction on the polymers containing hydroxylic pendant groups. The polymers were obtained in good yields and they were characterized by elemental analysis, infrared and proton nuclear magnetic resonance spectroscopy, gel permeation chromatography, dynamic thermogravimetric analysis and solution viscometry.

A simple, efficient and general one-pot method has been developed for the synthesis of aminophosphonates grafted on styrene-divinylbenzene copolymers from benzaldehyde grafted on styrene-divinylbenzene copolymer with amines and diethyl phosphite in tetrahydrofuran. The aminophosphonates grafted on insoluble macromolecular supports were characterized by infrared spectroscopy, thermogravimetric analysis and scanning electron microscopy. Keywords: aminophosphonate groups, stirene-divinylbenzene copolymers

Coating powders are finely grounded polymeric materials containing binders, pigments, extenders and special additives, used to obtain decorative and protective organic coatings. There are two major categories: thermoplastic and thermoreactive coating powders, based on thermoplastic and on thermoreactive binders, respectively. This paper presents the classes of thermoplastic coating powders, and their main characteristics.

Two compounds containing mesogenic cores based on dithiophene and dithienothiophene or fluorene units and hexyl end groups have been synthesized and their thermotropic properties were studied. The mesomorphic behaviour has been analyzed in the thermal stability range, by three complementary methods: polarized light microscopy, differential scanning calorymetry and variable temperature wide angle X ray diffraction. It was established that both compounds form a mesophase at low temperature, whose architecture depends by the mesogen molecular structure. By thermal treatment of the compounds in the mesophase stability range continuous ordered films have been obtained. Keywords: liquid crystal, internal plasticizer, ordered film

Assuming that the “structural” elements of a multiphase fluid (hydrogel, drug or fluid particles) move on continuous and non-differentiable curves (fractal curves), a new theoretical model that describes the drug release processes from polymeric hydrogels is established. This model, namely fractal hydrodynamic model, is based on two equations: the momentum and probability density conservation laws. The fractal potential, from the momentum conservation law, is a measure of the non-differentiability of the movement curves and controls the drug release processes. The model allows us to evaluate some characteristics of the hydrogel network, such as a distribution parameter for drug particle inside hydrogel. The novelty of this approach is that the system complexity is replaced by fractality, eliminating thus the whole classical “arsenal” of quantities from the standard physics based on the assumption of continuity and differentiability of physical quantities (differentiable physics). Keywords: fractal hydrodynamic, drug release, polymer, hydrogel

The carpet waste fibers and waste glass that create a serious environmental problem can be converted into useful products. The use of these waste materials in a cement-based composite can be a promising direction for waste reduction and resources conservation. In this study, several tests carried out to investigate the performance of control mortar using recycled glass and fibers as a fraction of aggregates in a cement-based composite. These tests included compressive strength, flexural strength, flexural toughness and water absorption. The results revealed that carpet waste fiber and waste glass could be reused as substitutes for conventional materials in cement-based composites. Keywords: Cement-based composite, carpet waste, waste glass, polypropylene fibers

The objective of this study was to develop some new hybrid hosts based on dendrimers and montmorillonite designed for 5-Fluorouracil drug encapsulation. The presence of drug within the hosts was pointed out using different methods like FTIR Spectroscopy, X-Ray Photoelectron Spectroscopy (XPS), Thermogravimetric analysis (TGA), UV-Vis Spectroscopy and X-Ray Diffraction. The UV-Vis results showed that the dendrimer type involved in the hybrid hosts influenced the drug release. Keywords: antitumoral drug, dendrimer, montmorillonite, drug release system

The thermo-mechanical behavior of silica-reinforced crosslinked elastomers has been examined by conducting shear thermorheological experiments and microstructural evaluation on two series of randomly crosslinked poly(dimethyl-siloxane) (PDMS). For all the samples studied here it was found that due to the featureless mechanical spectrum, the time temperature superposition (TTS) principle could not be applied to expand the accessible frequency range by the construction of master curves. Characterization of the filler particles before and after their inclusion into the PDMS matrix was conducted by dynamic light scattering (DLS) and transmission electron microscopy (TEM). These observations are discussed with respect to recent evidence that particle clustering may occur in non-crosslinked systems. Finally, short time high temperature aging (up to 30 hrs) experiments were observed not to influence the viscoelastic behaviour. Keywords: highly crosslinked siloxane elastomers, linear viscoelasticity, time-temperature superposition, silica filler