It has been demonstrated experimentally that pre-stretch affects the swelling of an elastomeric membrane when it is exposed to a solvent. We study theoretically the one-dimensional swelling of a pre-stretched thin elastomeric sheet, bonded to an impermeable rigid substrate, to quantify the influence of pre-stretch. We show that the solvent uptake increases when pre-stretch increases, both at eq...

Fluorescent molecular rotors belong to a group of twisted intramolecular charge transfer complexes (TICT) whose photophysical characteristics depend on their environment. In this study, the influence of solvent polarity and viscosity on several representative TICT compounds (three Coumarin derivatives, 4,4-dimethylaminobenzonitrile DMABN, 9-(dicyanovinyl)-julolidine DCVJ), was examined. While s...

A series of new squaraine rotaxanes have been synthesized with a tetralactam macrocycle and stopper groups of varying sizes and functionalities. In chloroform solvent, the relative size of the stopper group appears to have little influence on the high mechanical stability of the rotaxane structure. There is no evidence for unthreading (sometimes referred to as deslipping), even in the presence ...

Cationic biaryl derivatives were synthesized by Suzuki-Miyaura coupling of 3-bromonaphtho[1,2-b]quinolizinium bromide with arylboronic acids. The resulting cationic biaryl derivatives exhibit pronounced fluorosolvatochromic properties. First photophysical studies in different solvents showed that the emission energy of the biaryl derivatives decreases with increasing solvent polarity. This red-...

The 'guaco' lianous herb Mikania laevigata, which is widespread in Southern Brazil, is traditionally used to treat bronchitis, asthma and cough. This work investigates the influence of the extraction method, solvent:drug ratio, ethanol proportion, harvest season (summer or winter) and solvent heating on the physicochemical profile of the extracts (dry weight, density, pH) and the coumarin (1,2-...

Today, the economic consumption of biodegradable polymers is of capital importance in many applications. One of the most commonly used biopolymers is polylactic acid (PLA). The printability of the biodegradable film has not been fully investigated. This work tested the printability of polylactic acid (PLA) films and compared the print qualities to common packaging films like low density pol...

Compositionally dependent solution structure is found to influence the solubility, crystallisability and nucleation mechanism of eicosane when crystallising from toluene : acetone mixed-solvent solutions.

The influence of the sample matrix in the analysis of pesticides in vegetable samples has been studied in order to determine if the matrix content introduces a systematic or proportional (or both) bias in the measurements. Experiments have been carried out during a 4-month period, in which calibration curves, prepared in solvent and in vegetable matrix, were prepared and analysed. A statistical...