The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Novel blends made of ionic naphthalene thermotropic polymer (NTP) and poly(ethylene terephthalate) (PET) have been prepared by melt mixing. Homogeneous blends were formed when a small amount (5wt%) of ionic NTP was blended with PET; but, phase separation occurred at a higher composition of the ionic NTP (10wt%). Both the stiffness and the strength are enhanced in all the blends studied as compared...
By using a powder method, a new method for producing semiconductor/polymer nanocomposites, lead sulfide (PbS) nanoparticles were prepared and dispersed in either poly(methylmethacrylate-co-methacrylic acid) or poly(styrene-co-styrenesulfonic acid). The size of the nanoclusters was less than 2nm, and the size distribution was rather sharp, determined by UV–vis absorption spectroscopy. The absorption...
The effect of a small amount of ionic groups (interactions) on the morphology and deformation behavior of stoichiometric blends made of poly(styrene-co-styrenesulfonic acid) (SPS) and poly(methyl methacrylate-co-4-vinylpyridine) (MVP) was investigated by Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). FTIR data revealed that intermolecular ion–ion interactions...
Molecular composites have been prepared by mixing rigid rod molecules of PPTA anion (K-salt) and poly(propylene oxide) in a common solvent and compression molding the precipitated material. As the PPTA anion content of the composites is increased, an upward shift occurs in both the glass transition temperature and the decomposition temperature. The tensile strength, stiffness and resistance to stress...
The influence of a polar plasticizer glycerol, and a nonpolar plasticizer, dioctylphthalate (DOP), on the microstructure and relaxation properties of poly(methyl methacrylate) ionomers has been investigated by dynamic mechanical thermal analysis. The test results indicate that glycerol strongly interacts with and weakens the ionic cluster ‘phase’, and also significantly increases the mobility of backbone...
Modified PPTAs were made by introducing ionic, propanesulfonate groups and nonionic, propyl groups. Ionic groups caused polyelectrolyte behaviour for the modified PPTA in a polar solvent and propyl groups improved solubility of the modified polymer. Modified PPTA having small amounts of side groups (less than 40 mol% in total) showed birefringence, reflecting rigidity of polymer chains. In contrast,...
PPTA anion shows polyelectrolyte behaviour in solution and birefringence in film specimens, reflecting rigid conformation of backbone chains. The PPTA anion was blended with a flexible-coil polymer, poly(vinylpyridine) to make molecular composites. Optical clarity, polarizing optical microscopy, and dynamic mechanical thermal analysis all indicate the formation of homogeneous molecular composites...
The resistance to fracture under alternating cycles of stress is examined for sulfonated polystyrene (SPS) ionomers. The influence of ion content on the number of cycles to failure and on fracture surface morphology has been determined. At low ion contents below 3 mol%, the fatigue resistance was found to be essentially unaffected, or slightly increased; but, in the range of ion contents from 4...
The influence of ion content and ionomer morphology on deformation modes of poly(styrene-co-sodium methacrylate) ionomers has been examined. Dynamic mechanical thermal analysis indicates a morphology characteristic to amorphous ionomers: two separate loss peaks are observed, one associated with the glass transition of the multiplet-containing matrix phase and the higher temperature loss peak with...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.