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This paper reports the fabrication of conductive polypyrrole (PPy)-SiO2 hybrid thin films having a flat surface (surface roughness value < 10 nm) through vapor phase polymerization (VPP) of pyrrole and tetraethyl orthosilicate (TEOS) on a ferric p-toluenesulfonate-coated substrate. Substantial improvement in the physicochemical and electrical properties of the hybrid film, compared to those of...
Poly[2,2’-(m-phenylene)-5,5’-bibenzimidazole] (PBI) is used in extremely high temperature harsh environment applications. It is a unique engineering material that is formed into parts by powder-sintering at temperatures as high as 500 °C. Recently, ever increasing demands for high temperature polymers have led to significant interest in PBI such that engineering guidelines could be established for...
The sorption of CO2 in two commercial grades of multiblock copolymers (PolyActive™) is investigated using a magnetic suspension balance in the temperature range 30–70 °C. The isotherms follow Henry's law when the poly(ethylene glycol) (PEG) blocks of PolyActive™ are in a molten state. A significant deviation is observed when the PEG blocks are still in a semicrystalline state. Differential scanning...
Nucleating agents (NA) is a kind of the most important additives in polymer industry. The phenomena of NA self-assembling/crystallizing into various supramolecular aggregations in the polymer melt and showing different nucleation effects have been widely reported. However, the process of the self-assembly formation, which is essential for understanding the exact nucleating mechanism of NAs, is not...
This study illustrates that amine functional groups on the ends of telechelic poly(dimethylsiloxane) (PDMS) can undergo post-processing reactions with surface epoxy groups on graphene oxide (GO) to form a robust elastomer during simple heating. In these materials, GO acts both as a nanofiller which reinforces the mechanical properties and participates as a multifunctional crosslinker, thereby promoting...
Smart assemblies have been widely studied in recent years for their capability to respond to the environment. As a series of building blocks of smart assemblies, multi-stimuli responsive polymers have also attracted a great deal of attention. In this article, notable recent advances in the fields of synthesis and assembly of amine-containing polyethers are summarized. Amine-containing polyethers,...
A novel class of perfluorocyclobutyl (PFCB)-containing reactive polymer with adjustable phenolic hydroxyl contents (PFCB-OH-xx) has been developed. A serial of PFCB-OH-xx polymers with high molecular weights (Mw > 100,000) and narrow molecular weight distributions (Mw/Mn < 1.15), were facilely prepared from 2-methoxy-1,4-bis(trifluorovinyloxy)phenyl via thermal cyclopolymerization and demethylation...
Strain-induced crystallization (SIC) is studied in networks of epoxidized natural rubber crosslinked with eco-friendly dodecanedioic acid, by X-ray scattering measurements during cyclic stretching. An orientation parameter is calculated to quantitatively describe the behaviour of the amorphous phase during loading and unloading. Comparison with sulphur-vulcanized rubbers shows that SIC lattice parameters...
Polypeptides bearing a reactive alkene moiety, including poly-dl-allylglycine (PGly(allyl)) and poly-dl-pentenylglycine (PGly(pent)) have been prepared through the polycondensation of activated urethane derivatives, N-phenoxycarbonyl derivative of α-amino acids. These urethane derivatives of dl-allylglycine (NPC-Gly(allyl)) and dl-pentenylglycine (NPC-Gly(pent)), are prepared by the N-carbamylation...
The role of polymeric tethers on the effective thermal conductivity of polymer nanocomposites is evaluated for the particular case of silica particle fillers dispersed within poly(methyl methacrylate) (PMMA). The effective thermal conductivity of both thin film and bulk composites is found to sensitively depend on the interaction between tethered and matrix chains. In particular, tethering of polymeric...
Complexes were formed via the electrostatic interaction between 30–50 nm anionic liposomes and a star-shaped polyelectrolyte, poly{[2-(methacryloyloxy)ethyl]trimethyl ammonium iodide}, having cationic arms that radiate from a silicon-based central core. The complexation was investigated with attention given to assessing the capacity of the cationic stars for the anionic liposomes (both liquid and...
Two donor–acceptor polymer semiconductors based on highly electron-deficient pyrrolo[3,4-d]pyridazine-5,7-dione unit were synthesized by Stille cross-coupling polymerization, and their thermal property, photophysical property, electrochemical property, microstructure, application as organic thin-film transistors, and photovoltaic property were investigated. Because of the strong electron-accepting...
In the present work, solution-blowing was adopted to form nanofibers from fish sarcoplasmic proteins (FSPs). Nanofiber mats containing different weight ratios (up to 90/10) of FSP in the FSP/nylon 6 blended nanofibers were formed from formic acid solutions, and compared to electrospun fibers made from the same solutions. The nanofiber mats produced by the two methods were characterized in terms of...
Miktoarm star copolymers, which are in the simplest form of branching, are particularly of interest to biomedical applications. Nevertheless, their synthesis is facing troubles of seeking inner cores with heterogeneous functional groups as well as tedious protection and deprotection. Herein, ethyl-β-d-glucopyranoside, a sugar molecule containing homogeneous groups, was directly employed as a core...
Aiming the obtainment of materials with useful properties for bio-applications, as thermal and mechanical (in particular flexibility), chitosan and low molecular weight poly(lactic acid) were chosen due to their biodegradability and biocompatibility in various bio-environments. Networks formed by oligo(dl-lactic acid) segments linked to the chitosan chains were prepared, in which the ratio between...
Polymeric ionic liquids (PILs) have emerged as promising membrane materials for CO2 separation. The present work is aimed at investigating the effects of incorporation of rigid polyaromatic hydrocarbons, viz., pyrene and anthracene, in polybenzimidazole-based PILs. The effects of substituent and anion variation on the gas permeation properties of PILs using pure gases were examined at 20 atm upstream...
Heat-induced gelation mechanism of ovalbumin (OVA) in neutral, salt-free aqueous solution was investigated by dynamic light scattering and small-angle neutron scattering. The scattering profiles obtained from OVA solutions/gels showed a correlation peak. It is clarified that the position of the peaks was independent of the concentration after heating. From this fact, we described the gelation mechanism...
Chitosan Oligosaccharide (COS) nanoparticles prepared by ionotropic gelation method using sodium tri-polyphosphate (Na-TPP) coated with Hyaluronic acid (HA). The coating confers biological advantage to the nanoparticles in terms improved circulation time in the plasma and targeting ability. This nanoparticulate system has potential application in targeted nucleic acid delivery as they can be tuned...
The temperature dependence of structural development in a self-exfoliating nano-composite system has been studied utilizing time resolved small angle x-ray scattering (SAXS) and time resolved mechanical spectroscopy (TRMS) employing small amplitude oscillatory shear (SAOS). This system consists of a montmorillonite organoclay and end-functionalized polybutadiene. Self-exfoliation refers to a system...
Graphene oxide produced by Tour's method (GO) and GO functionalized with 4-4′ oxydianiline (ODAGO) are incorporated at 0.01 to 0.10 weight percent (wt%) into a polyimide (PI) made from 3,3′-benzophenonetetracarboxylic dianhydride (BTDA) and 4-4′ oxydianiline (ODA). The performance properties of these two systems GO-PI and ODAGO-PI at extremely low GO concentrations are compared. ODAGO-PI nanocomposite's...
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