The mechanical properties of electrospun fibers play an important role in determining their applications. Most the reported literature measures mats, scaffolds, or films instead single fibers; however, a basic understanding relationship between fiber and that mat is critical to obtain precise information for choosing application. This Review aims evaluate variables influence those properties. An overview on recent inputs development given, illustrating attempts tailor and/or mats. necessity...

Sodium hyaluronate NaHA in phosphate-buffered saline behaves as a typical polyelectrolyte the high-salt limit, Newtonian viscosities are observed over wide range of shear rates. There is no evidence intermolecule hydrogen bonding causing gel formation solutions without protein present. The concentration dependences viscosity, relaxation time, and terminal modulus consistent with observations on flexible, neutral polymers good solvents, which known to be same universality class flexible...

Chitosan-based, defect-free nanofibers with average diameters ranging from 62 ± 9 nm to 129 16 were fabricated via electrospinning blended solutions of chitosan and polyethylene oxide (PEO). Several solution parameters such as acetic acid concentration, polymer molecular weight investigated optimize fiber consistency diameter. These evaluated using the rheological properties well images produced by scanning electron microscopy (SEM) electrospun nanofibers. Generally, SEM imaging demonstrated...

Bovine synovial fluid and albumin solutions of similar concentration are rheopectic (stress increases with time in steady shear). This unusual flow characteristic is caused by protein aggregation, the total stress enhanced entanglement this tenuous network long-chain polysaccharide sodium hyaluronate under physiological conditions. Neutron scattering measurements on demonstrate aggregation all consistent a weak dipolar attraction energy (of order 3 kT ) that most likely augmented hydrophobic...

Chitosan is an abundantly common, naturally occurring, polysaccharide biopolymer. Its biocompatible, biodegradable, and antimicrobial properties have led to significant research toward biological applications such as drug delivery, artificial tissue scaffolds for functional engineering, wound-healing dressings. For scaffolding, formation of highly porous mats nanometer-sized fibers, those fabricated via electrospinning, may be quite important. Previously, strong acidic solvents blending with...

Graphene oxide was successfully reduced to graphene using a bacterial cellulose culture medium that further processed fabricate <italic>in situ</italic> composites of cellulose/reduced gelatinous hybrids, aerogels, and membranes.

The development of an innovative interfacial wetting strategy known as liquid infused systems offers great promise for the advanced design superwetting and superantiwetting substrates to overcome drawbacks textured surfaces classified under heading Cassie/Wenzel states. potential value nature-inspired has significant address scientific technological challenges within field chemistry. objective current review is provide insights into a fruitful young research, highlight its historical...

Bacterial cellulose (BC) nanofibers secreted by <italic>Komagataeibacter xylinus</italic> 10245 were applied alone or with chitosan to prepare highly aligned and porous scaffolds through a liquid nitrogen-initiated ice “templating” freeze-drying process.

Using the de Gennes scaling model for configuration of a polyelectrolyte chain in semidilute solution, we construct simple AC conductivity solutions strongly charged polyelectrolytes without added salt. We compare predictions this with literature data and new on two very different affinities water. The sodium salt sulfonated polystyrene water is hydrophobic (the uncharged monomer does not dissolve water), where locally collapsed. poly(2-acrylamido-2-methylpropanesulfonate), much more...

The engineering of supports for enzyme immobilization while retaining competent functionality is nontrivial.

A facile and effective method is described to engineer original bacterial cellulose fibrous networks with tunable porosity. We showed that the pore shape, volume, size distribution of nanocellulose membranes can be tailored under appropriate culture conditions specifically carbon sources. Pore characterization techniques such as capillary flow porometry, bubble point method, gas adsorption-desorption technique well visualization scanning electron atomic force microscopy were utilized...

The goal of this work was to use molecular dynamics (MD) simulations build amorphous surface layers polypropylene (PP) and cellulose inspect their physical interfacial properties. A new method produce models for these surfaces developed, which involved the a “soft” confining layer comprised xenon crystal. This compacts polymers into density distribution degree roughness that corresponds well experimental values. In addition, calculated properties such as density, cohesive energy coefficient...

We report rheological data on anionic polyelectrolyte solutions of variable chain length and concentration, specifically sodium poly(2-acrylamido-2-methylpropanesulfonate), with no added salt. Our results are consistent literature the salt sulfonated polystyrene. find a strong dependence viscosity η length: ∼ M2.4. This is in reasonable agreement scaling theory proposed by Witten Pincus (η M2) much stronger than prediction Dobrynin et al. M). The ratio relaxation time gives modulus at time,...

An assay technique capable of differentiating six to nine types CNS drug specificity is described. The method involves an intravenous infusion Metrazol mice by motor driven apparatus and utilizes a polyethylene cannula permit free movement the animals during infusion. The differential effect drugs on three relatively independent endpoints (Metrazol threshold, extensor tonus time death), observable in each animal studied, forms basis for determination specificity. The following drugs, among...

Using the dielectric strength and relaxation time of a high-frequency (1 MHz−1 GHz) relaxation, we estimate effective charge on polyelectrolytes their net thermodynamic repulsive interaction with solvent. The utility this method is demonstrated for semidilute aqueous solutions sodium salt several sulfonated varying water, no added salt. At high concentrations, as concentration increased, strongly charged always increases, previously observed in conductivity osmotic pressure measurements....

Nanocellulose fibers bioengineered by bacteria are a high-performance three-dimensional cross-linked network which can confine dispersed liquid medium such as water. The strong chemical and physical interactions of water molecules with the entangled cellulosic allow these materials to be ideal substrates for effective separation. This type phenomenon characterized green no equivalent precedent; its performance sustainability relative other cellulose-based or synthetic membranes shown herein...

Poly[bis(adamantylamino-co-trifluoroethoxy)phosphazene], poly[bis(adamantyloxy-co-trifluoroethoxy)phosphazene], and poly[bis(adamantylmethoxy-co-trifluoroethoxy)phosphazene] with different ratios of adamantyl to trifluoroethoxy groups were synthesized by macromolecular substitution. This work was preceded model compound studies cyclophosphazene trimers tetramers. Polymers in which all the side units could not be prepared because steric restrictions imposed groups. However, mixed-substituent...

Pt/carbon composite nanofibers were prepared by depositing Pt nanoparticles directly onto electrospun carbon using a polyol processing technique. The morphology and size of controlled 1-aminopyrene functionalization. noncovalent functionalization is simple can be carried out at ambient temperature without damaging the integrity electronic structure nanofibers. resulting characterized running cyclic voltammograms in 0.5 M H2SO4 0.125 CH3OH + 0.2 solutions. Results show that with have smaller...