scholarly journals Kinetic Studies on Lipase-Catalyzed Acetylation of 2-Alkanol with Vinyl Acetate in Organic Solvent

2007 ◽  
Vol 56 (6) ◽  
pp. 309-317 ◽  
Author(s):  
Hirofumi Hirata ◽  
Mio Kawanishi ◽  
Yusuke Iwata ◽  
Keiji Sakaki ◽  
Hiroshi Yanagishita
Keyword(s):  
Organic Solvent ◽  
Vinyl Acetate ◽  
Kinetic Studies

scholarly journals Kinetic Studies on the Optical Resolution of 2-Alkanol by Pseudomonas cepaciaLipase Catalyzed Transesterification with Vinyl Acetate in Organic Solvent.

2002 ◽  
Vol 51 (10) ◽  
pp. 643-653 ◽  
Author(s):  
Masako OHNO ◽  
Naoki KAMO ◽  
Takashi KITAMOTO ◽  
Naoya YAMAZATO ◽  
Naoki HOSHIBA ◽  
...  
Keyword(s):  
Organic Solvent ◽  
Vinyl Acetate ◽  
Optical Resolution ◽  
Kinetic Studies

scholarly journals Kinetic Studies on Lipase-Catalyzed Acetylation of 1-Alkanol with Vinyl Acetate in Organic Solvent

2006 ◽  
Vol 55 (5) ◽  
pp. 239-248 ◽  
Author(s):  
Hirofumi HIRATA ◽  
Gen KONDO ◽  
Keiyo KAWAUCHI ◽  
Yun-Gang CHEN ◽  
Keiji SAKAKI ◽  
...  
Keyword(s):  
Organic Solvent ◽  
Vinyl Acetate ◽  
Kinetic Studies

scholarly journals Testing the Effectiveness of Protocols for Removal of Common Conservation Treatments for Radiocarbon Dating

Radiocarbon ◽  
2017 ◽  
Vol 60 (1) ◽  
pp. 35-50 ◽  
Author(s):  
Fiona Brock ◽  
Michael Dee ◽  
Andrew Hughes ◽  
Christophe Snoeck ◽  
Richard Staff ◽  
...  
Keyword(s):  
Organic Solvent ◽  
Vinyl Acetate ◽  
Radiocarbon Dating ◽  
Cellulose Nitrate ◽  
Acid Base ◽  
Acrylic Polymers ◽  
Archaeological Wood ◽  
Conservation Treatment ◽  
Chemical Pretreatments ◽  
Selection Of

AbstractTo achieve a reliable radiocarbon (14C) date for an object, any contamination that may be of a different age must be removed prior to dating. Samples that have been conserved with treatments such as adhesives, varnishes or consolidants can pose a particular challenge to 14C dating. At the Oxford Radiocarbon Accelerator Unit (ORAU), common examples of such substances encountered include shellac, the acrylic polymers Paraloid B-67 and B-72, and vinyl acetate-derived polymers (e.g. PVA). Here, a non-carbon-containing absorbent substrate called Chromosorb® was deliberately contaminated with a range of varieties or brands of these conservation treatments, as well as two cellulose nitrate lacquers. A selection of chemical pretreatments was tested for their efficiency at removing them. While the varieties of shellac and Paraloid tested were completely removed with some treatments (water/methanol and acetone/methanol/chloroform sequential washes, respectively), no method was found that was capable of completely removing any of the vinyl acetate-derived materials or the cellulose nitrate lacquers. While Chromosorb is not an exact analog of archaeological wood or bone, for example, this study suggests that it may be possible to remove aged shellac and Paraloid from archaeological specimens with standard organic solvent-acid-base-acid pretreatments, but it may be significantly more difficult to remove vinyl acetate-derived polymers and cellulose nitrate lacquers sufficiently to provide reliable 14C dates. The four categories of conservation treatment studied demonstrate characteristic FTIR spectra, while highlighting subtle chemical and molecular differences between different varieties of shellac, Paraloid and cellulose nitrate lacquers, and significant differences between the vinyl acetate derivatives.

scholarly journals Application of Singh-Jha Equation in the Evaluation of b* Parameter of Laidler-Landskroener Equation in the Hydrolysis of Vinyl Acetate

2010 ◽  
Vol 7 (4) ◽  
pp. 1170-1173
Author(s):  
Sangita Sharma ◽  
Bijal Vyas ◽  
Falguni Thakkar ◽  
Ketan Patel ◽  
J. J. Vora
Keyword(s):  
Organic Solvent ◽  
Transition State ◽  
Vinyl Acetate ◽  
Alkaline Hydrolysis ◽  
Initial State ◽  
Closed Approach ◽  
Rate Of Hydrolysis ◽  
Solvent Molecules ◽  
Hydrolysis Of

Singh-Jha method is applied to calculate b* of Laidler-Landskroener equation, the distance of closed approach of solvent molecules to the activated complexes in alkaline hydrolysis of vinyl acetate. This method is applied to alkaline hydrolysis of vinyl acetate in water enriched ethanol between 30 °C and 35 °C. The rate of hydrolysis decreases with the increase of content of organic solvent at both temperatures. The size of transition state was found to be large as compared to the initial state. The b* was found to be 3.7693Å which is in agreement with the values obtained earlier.

KINETIC STUDIES OF SEMI-BATCH EMULSION CO-POLYMERIZATION OF 80:20 VINYL ACETATE-BUTYL ACRYLATE

1984 ◽  
Vol 5 (3-4) ◽  
pp. 301-322 ◽  
Author(s):  
T. Makgawinata ◽  
M.S. El-Aasser ◽  
A. Klein ◽  
J.W. Vanderhoff
Keyword(s):  
Vinyl Acetate ◽  
Butyl Acrylate ◽  
Kinetic Studies

Free-radical homo- and copolymerization of vinyl acetate and n-butyl acrylate: Kinetic studies by online 1H NMR kinetic experiments

2011 ◽  
Vol 123 (1) ◽  
pp. 543-553 ◽  
Author(s):  
Mahdi Abdollahi ◽  
Bakhshali Massoumi ◽  
Mohammad Reza Yousefi ◽  
Farshid Ziaee
Keyword(s):  
Free Radical ◽  
Vinyl Acetate ◽  
1H Nmr ◽  
Butyl Acrylate ◽  
Kinetic Studies

The electrocopolymerization of styrene with vinyl acetate in an organic solvent

1989 ◽  
Vol 27 (3) ◽  
pp. 847-854
Author(s):  
Bettina A. L. Calafate ◽  
Maria Elizabeth F. Garcia ◽  
Eloisa B. Mano
Keyword(s):  
Organic Solvent ◽  
Vinyl Acetate
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