scholarly journals Preparation of a Water-Based Photoreactive Azosulphonate-Doped Poly(Vinyl Alcohol) and the Investigation of Its UV Response

Polymers ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 169 ◽  
Author(s):  
Philipp Nothdurft ◽  
Jörg Schauberger ◽  
Gisbert Riess ◽  
Wolfgang Kern
Keyword(s):  
Vinyl Alcohol ◽  
Water Solubility ◽  
Uv Spectroscopy ◽  
Poly Vinyl Alcohol ◽  
Resonance Spectroscopy ◽  
Aromatic Rings ◽  
13C Nuclear Magnetic Resonance ◽  
Vis Spectroscopy ◽  
Water Based ◽  
Uv Response

Two different azosulphonate dyes were synthesised and purified for the preparation of a water-based photoreactive azosulphonate-doped poly(vinyl alcohol). The aim was the investigation of a novel azosulphonate-poly(vinyl alcohol) photoresist with decreased water solubility after illumination, setting a focus on environmentally benign substances. The electron distribution of the aromatic rings of the two different azosulphonate molecules were changed by the UV-induced cleavage of the –N=N–SO3− groups, which was evidenced by UV spectroscopy. The formation of ester groups was detected by Fourier-transform infrared and 13C nuclear magnetic resonance spectroscopy. UV–Vis spectroscopy was used to investigate the photoreactivity of the prepared films. Photolithographic experiments demonstrated the applicability of these newly produced materials as photoresist materials. In addition, these materials provide high thermal stability.

scholarly journals 8-Hydroxyquinoline-5-Sulfonic Acid-Containing Poly(Vinyl Alcohol)/Chitosan Electrospun Materials and Their Cu2+ and Fe3+ Complexes: Preparation, Antibacterial, Antifungal and Antitumor Activities

Polymers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2690
Author(s):  
Milena Ignatova ◽  
Nevena Manolova ◽  
Iliya Rashkov ◽  
Nadya Markova ◽  
Rositsa Kukeva ◽  
...  
Keyword(s):  
Vinyl Alcohol ◽  
Sulfonic Acid ◽  
Electron Paramagnetic Resonance Spectroscopy ◽  
Local Treatment ◽  
Poly Vinyl Alcohol ◽  
Resonance Spectroscopy ◽  
Fibrous Materials ◽  
Antitumor Activities ◽  
Antibacterial And Antifungal Activities

Novel poly(vinyl alcohol) (PVA)/chitosan (Ch)-based fibrous materials containing an ionizable model drug, 8-hydroxyquinoline-5-sulfonic acid (SQ), were successfully fabricated by electrospinning. Complexes between the components of the crosslinked PVA/Ch/SQ mats and Cu2+ and Fe3+ ions were formed. The coordination of these ions in the mats was examined by electron paramagnetic resonance spectroscopy (EPR). The microbiological screening against S. aureus and C. albicans revealed that both the incorporation of SQ in the mats and the complexation with Cu2+ and Fe3+ imparted to these materials antibacterial and antifungal activities. Moreover, the SQ-containing mats and their complexes displayed good cytotoxicity against human cervical HeLa tumor cells. The most prominent was the cytotoxicity of the Cu2+ complex of the mats. The combined antibacterial, antifungal and in vitro antitumor activities render these novel materials promising candidates for wound dressing applications and for application in the local treatment of cervical tumors.

Ionic Impurities in Poly(vinyl alcohol) Gate Dielectrics and Hysteresis Effects in Organic Field Effect Transistors

2008 ◽  
Vol 1091 ◽  
Author(s):  
Martin Egginger ◽  
Mihai Irimia-Vladu ◽  
Reinhard Schwödiauer ◽  
Andreas Tanda ◽  
Siegfried Bauer ◽  
...  
Keyword(s):  
Vinyl Alcohol ◽  
Field Effect ◽  
Water Solubility ◽  
Field Effect Transistors ◽  
Gate Insulator ◽  
Poly Vinyl Alcohol ◽  
Organic Field Effect Transistors ◽  
Electronic Circuits ◽  
Metal Insulator Metal ◽  
Ionic Impurities

AbstractPoly(vinyl alcohol) (PVA) is a water based dielectric often used as a coating layer in paper industry. Due to its water solubility PVA is also interesting as gate insulator in organic field effect transistors. Depending on the preparation of the PVA gate, transistors with and without hysteresis can be produced, with applications in organic electronic circuits or memory elements. In the production of PVA, a major side product is sodium acetate, an ionic salt not completely removed during industrial purification. Such ionic impurities likely influence the hysteresis in PVA based organic field effect transistors. While a hysteresis is desirable in memory elements it is unwanted in transistors for electronic circuits. Ways to prepare transistors with a desired transfer characteristic are described, for example by using electronic grade products directly from the purchaser of PVA, or by employing PVA purified by means of dialysis. Measurements are performed with metal-insulator-metal (MIM) structures and organic field effect transistors (OFETs), where Buckminsterfullerene C60 is employed as organic semiconductor.

scholarly journals Effect of boric acid on poly vinyl alcohol- tannin blend and its application as water-based wood adhesive

2020 ◽  
Vol 23 (1) ◽  
pp. 188-196
Author(s):  
Ravindra V. Gadhave ◽  
Vineeth S.K. ◽  
Pritam V. Dhawale ◽  
Pradeep T. Gadekar
Keyword(s):  
Boric Acid ◽  
Vinyl Alcohol ◽  
Wood Adhesive ◽  
Poly Vinyl Alcohol ◽  
Water Based

Genesis of podzols on coastal dunes in southern Queensland .IV . Nature of the organic fraction as seen by 13C nuclear magnetic resonance spectroscopy

Soil Research ◽  
1992 ◽  
Vol 30 (5) ◽  
pp. 667 ◽  
Author(s):  
JO Skjemstad ◽  
AG Waters ◽  
JV Hanna ◽  
JM Oades
Keyword(s):  
Organic Matter ◽  
Carboxylic Acid ◽  
Signal To Noise Ratio ◽  
Coastal Dunes ◽  
Resonance Spectroscopy ◽  
Organic Fraction ◽  
Aromatic Rings ◽  
13C Nuclear Magnetic Resonance ◽  
Close Proximity ◽  
Inorganic Components

The organic matter in the A, Bh, Bhs and Bs horizons from a number of profiles from a chronosequence of podzols spanning some 7x105 years was studied using solid state 13C n.m.r. spectroscopy. Organic matter was effectively concentrated without chemicals using a Spex mixer and sedimentation. Acid dithionite treatment of samples containing appreciable amounts of iron significantly improved the signal to noise ratio. Acid oxalate treatment had a lesser effect. The organic matter from the A horizon was highly aromatic but was low in carboxylic acids. In the B horizons, aromaticity decreased in the order Bh-Bhs-Bs and increased with the degree of profile development. Only in the Bh horizons of the older highly developed profiles did aromatic carbon exceed alkyl carbon. The 'core' structure of these materials appeared to be aromatic rings heavily substituted (>90%) with alkyl and carboxylic acid groups. The Bhs and Bs horizons contained substantial amounts of carboxylic acid substituted alkyls with structures similar to the polymaleic or hydroxy acid models. Sixty per cent of the organic matter removed with iron on dithionite treatment was found to be alkyl. The aromatic and alkyl dominated horizons can exist in close proximity, occurring less than 10 cm apart in the case of the giant pipey podzols. None of the current theories on podzol genesis can adequately explain the arrangement of organic and inorganic components found in these profiles and a revised model based on existing theories is proposed.

Poly(Vinyl Alcohol) (Core)-Polyurethane (Shell) Nanofibers Produced by Coaxial Electrospinning

2016 ◽  
Vol 705 ◽  
pp. 68-71 ◽  
Author(s):  
Ga Young Park ◽  
So Young Lee ◽  
Woo Jin Kim ◽  
Jin Hyun Choi
Keyword(s):  
Vinyl Alcohol ◽  
Water Soluble ◽  
Polymer Mixture ◽  
Poly Vinyl Alcohol ◽  
Coaxial Electrospinning ◽  
Resonance Spectroscopy ◽  
Bioactive Substances ◽  
Water Contact ◽  
Water Soluble Polymer ◽  
Small Pore

Nanoweb fabricated by electrospinning has a large specific area and a small pore size which can be controlled through a spinning process to enable a strong adsorption and selective permeability. It is required to produce nanofiber of different polymer mixture with a limited miscibility for improvement of physical, chemical, or biological properties. In this study, poly (vinyl alcohol) (PVA)/polyurethane (PU) nanofibers were produced by coaxial electrospinning. PVA (core)/PU (shell) nanofibers were defect-free and had a uniform thickness. The pseudo core/shell structure of PVA/PU nanofibers was confirmed by transmission electron microscopy. The presence of PVA and PU in the nanofibers was identified by 13C solid state nuclear magnetic resonance spectroscopy, fourier transform infrared spectroscopy, and X-ray diffraction analysis. Water contact angle was reduced by incorporation of PVA in a core of PU nanofiber. For variety of biomedical applications, bioactive substances such as antibiotics and proteins can be incorporated in a core of hydrophobic PU nanofiber by coaxial electrospinning of water-soluble polymer/bioactive substance mixture.

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