http://nathan.instras.com/ResearchProposalDB/doc-109.pdf

A review on polymer nanofibers by electrospinning and their applications in nanocomposites

Electrospinning: a fascinating fiber fabrication technique.

Electrospinning is a highly versatile method to process solutions or melts, mainly of polymers, into continuous fibers with diameters ranging from a few micrometers to a few nanometers. This technique is applicable to virtually every soluble or fusible polymer. The polymers can be chemically modified and can also be tailored with additives ranging from simple carbon-black particles to complex species such as enzymes, viruses, and bacteria. Electrospinning appears to be straightforward, but is a rather intricate process that depends on a multitude of molecular, process, and technical parameters. The method provides access to entirely new materials, which may have complex chemical structures. Electrospinning is not only a focus of intense academic investigation; the technique is already being applied in many technological areas.

Electrospinning: A Fascinating Method for the Preparation of Ultrathin Fibers

Progress in preparation, processing and applications of polyaniline

Electrospinning has been applied to prepare uniaxially aligned nanofibers made of organic polymers, ceramics, and polymer/ceramic composites The key to the success of this method was the use of a collector consisting of two pieces of electrically conductive substrates separated by a gap whose width could be varied from hundreds of micrometers to several centimeters As driven by electrostatic interactions, the charged nanofibers were stretched to span across the gap and thus to become uniaxially aligned arrays over large areas Because the nanofibers were suspended over the gap, they could be conveniently transferred onto the surfaces of other substrates for subsequent treatments and various applications Materials that have been successfully incorporated into this procedure include conventional organic polymers, graphite carbon, and metal oxides By controlling the parameters for electrospinning, we have also fabricated a number of simple device structures, for example, an individual nanofiber spanning 

http://nathan.instras.com/ResearchProposalDB/doc-120.pdf

Electrospinning of polymeric and ceramic nanofibers as uniaxially aligned arrays

The first use of electrospun nanofibrous membranes as highly responsive fluorescence quenching-based optical sensors for metal ions (Fe3+ and Hg2+) and 2,4-dinitrotoluene (DNT) is reported. A fluorescent polymer, poly(acrylic acid)−poly(pyrene methanol) (PAA−PM), was used as a sensing material. Optical chemical sensors were fabricated by electrospinning PAA−PM and thermally cross-linkable polyurethane latex mixture solutions. These sensors showed high sensitivities due to the high surface area-to-volume ratio of the nanofibrous membrane structures.

Electrospun Nanofibrous Membranes for Highly Sensitive Optical Sensors

A novel strategy for the enzymatic synthesis of a water-soluble, conducting polyaniline (PANI)/sulfonated polystyrene (SPS) complex is presented. The enzyme horseradish peroxidase (HRP) is used to polymerize aniline in the presence of a polyanionic template, sulfonated polystyrene. The synthesis is simple, and the conditions are mild in that the polymerization may be carried out in a 4.3 pH buffered aqueous solution, with a stoichiometric amount of hydrogen peroxide and a catalytic amount of enzyme. UV−visible absorption, FTIR, GPC, elemental analysis, and conductivity measurements all confirm that the electroactive form of PANI, similar to that which is traditionally chemically synthesized, is formed and complexed to the SPS. The reversible redox activity of the polyaniline displays a unique hysteresis loop with pH change. Cyclic voltammetry studies show only one set of redox peaks over the potential range of −0.2 to 1.2V, which suggests that the PANI/SPS complex is oxidatively more stable. The conductiv...

Enzymatically Synthesized Conducting Polyaniline

Electrospinning is a process for making extremely fine submicron fiber by a process of charging polymer solutions to thousands of volts. This method of manufacturing man-made fibers has been known since 1934, when the first patent on electrospinning was filed by Formhals'. Since that time, many patents and publications have been reported on electrospinning. This paper describes our latest accomplishments in the development of useful fabric membranes from electrospun fibers and describes the properties of these membranes with respect to their strength and performance as protective layers. This paper reviews the electrospinning process and its current status as a manufacturing method. New data and properties of electrospun membranes are reported, including structural effects upon moisture transport, air convection, aerosol filtration, porosity, tensile strength, and enhanced chemical activity of these membranes, demonstrating the potential of these nanofiber layers in laminates for specialty textiles.

Protective textile materials based on electrospun nanofibers

Polymers were synthesized from substituted phenolic and aromatic amine compounds with hydrogen peroxide as the source of an oxidizing agent and horseradish peroxidase enzyme as the catalyst. The polymerization reaction was carried out in a monophasic organic solvent with small amounts of water at room temperature. Conditions for the synthesis of polymers with respect to reaction time and yield were studied with a number of monomers at different concentrations and in solvents with different buffers with pH range of 5.0–7.5. Physical and chemical properties of these homo-and copolymers were determined with respect to melting point, solubility, elemental analysis, molecular weight distribution, infrared absorption (including FTIR), solid-state 13C nuclear magnetic resonance, thermal gravimetric analysis, and differential scanning calorimetry. The enzyme catalyzed reactions produced polymers of molecular weight greater than 400,000 which were further fractionated by differential solubility in solvent mixtures and the molecular weight distribution of the polymer fractions were determined. In general, the polymers synthesized have low solubilities, high melting points, and some degree of branching.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/pola.1991.080291105

Synthesis and characterization of polymers produced by horseradish peroxidase in dioxane

Zwitterionic sulfobetaine polymers with a catechol chain end (DOPA-PSB) were applied to a variety of hydrophobic polymer sheets and fibers. In addition, a silica surface was tested as a representative hydrophilic substrate. The polymer-coated surfaces showed significantly lower fouling levels than uncoated controls. Because of the anti-polyelectrolyte nature of sulfobetaine zwitterionic polymers, the effect of salt concentration on the coating solutions and the quality of the polymer coating against fouling are studied. The coating method involves only water-based solutions, which is compatible with most surfaces and is environmentally friendly. To demonstrate the versatility of the reported method, we evaluated the fouling levels of the polymer coating on commonly used polymeric surfaces such as polypropylene (PP), polydimethylsiloxane (PDMS), polystyrene (PS), nylon, polyvinyl chloride (PVC), and poly(methyl methacrylate) (PMMA).

Kris Senecal

Papers

Electrospun Nanofibrous Membranes for Highly Sensitive Optical Sensors

Enzymatically Synthesized Conducting Polyaniline

Protective textile materials based on electrospun nanofibers

Synthesis and characterization of polymers produced by horseradish peroxidase in dioxane

One-step dip coating of zwitterionic sulfobetaine polymers on hydrophobic and hydrophilic surfaces.