background and objectives: kefiran (kef) is a water-soluble polysaccharide that can form transparent film however, it is brittle. therefore, in order to improve the mechanical properties of kefiran film, a mixture with other polymers can be offered. the expansion of mixed systems can propose kefiran and polyvinyl alcohol (pvoh) as a new composite film. materials and methods: solutions of 20 gra...

the effects of operating parameters such as feed temperature and permeate-side pressure on the performance of a commercial pva membrane in the dehydration of toluene by a pervaporation (pv) membrane system is studied in the present work. the results obtained indicate that increasing temperature in the range of 40 to 70 °c and reducing permeate pressure in the range of 1 to 10 mmhg increase memb...

In this paper, we studied a new preparation method of microcapsules for entrapment of genetically engineered cells. Polyvinyl alcohol microcapsules having well defined shape, high mechanical strength, good biochemical and permeability properties were prepared by using low temperature physical cross-linking method. Comparing with currently used alginate-polylysine-alginate microcapsules, polyvin...

Polyvinyl alcohol and calcium oxide composites appeared by casting technique. The calcium oxide added to polyvinyl alcohol with different weight percentages are (0,1,2 and 3) wt.%. Results showed that the absorbance increases with increase the weight percentage of calcium oxide. The absorption coefficient, extinction coefficient, refractive index and real and imaginary parts of dielectric const...

Films of oriented bacteriorhodopsin have been formed in polyvinyl alcohol with excellent optical quality. Images with high contrast have been impressed and erased on these films. Second-harmonic microscopy has been used to read the image on a bacteriorhodopsin-polyvinyl alcohol film without erasure. The potential of these films for molecular information storage and computation is discussed.

A novel nanocomposite polyvinyl alcohol precursor-based material dispersed with the web of carbon microfibers and carbon nanofibers is developed as lithium (Li)-ion electrolyte battery separator. The primary synthesis steps of the separator material consist of esterification of polyvinyl acetate to produce polyvinyl alcohol gel, ball-milling of the surfactant dispersed carbon micro-nanofibers, ...

background and objectives: preparation and evaluation of nanocomposite films have become prevalent in recent years. one of the most important methods for dispersing nanoparticles in polymers is the use of ultrasound radiation. polyvinyl alcohol-montmorillonite (pva-mmt) nanocomposite films were prepared via solvent casting method. materials and methods: the effects of different ultrasound times...

nowadays, hydrogels are widely used as wound dressings in biomedical applications. similar to other types of the moist (wet) wound dressings, it is necessary to have sufficient information about their dehydration kinetics during the pre-usage period (e.g. storage duration) and also the wound healing process. in this work, hydrogel wound dressings based on polyvinyl alcohol were prepared by cycl...

we report the synthesized and preparation of graphene oxide (go) nanocomposite functionalized with polyvinyl alcohol (pva) with different concentration of graphene oxide 0, 1, 1.5, 2, 2.5, 3, 3.5 and 4% weight. this synthesized confirmed by ft-ir. the electrical conductivity of the all nanocomposite was measured at 25°c for all samples and the resulted showed electrical conductivity was increas...