Note High Yield Synthesis of Low Molecular Weight Poly(Vinyl Acetate) in Aqueous Acidic Media

1989 ◽  
Vol 26 (12) ◽  
pp. 1661-1664
Author(s):  
G. C. Joshi ◽  
A. K. Chatterjee ◽  
P. S. N. Murthy
Keyword(s):  
Molecular Weight ◽  
Vinyl Acetate ◽  
High Yield ◽  
Low Molecular Weight ◽  
Acidic Media

Influence of low-molecular-weight copolymers of ethylene with vinyl acetate on the low-temperature properties of diesel fuel

1974 ◽  
Vol 10 (8) ◽  
pp. 615-618 ◽  
Author(s):  
G. G. Krasnyanskaya ◽  
B. V. Gryaznov ◽  
V. A. Kryunina ◽  
S. L. Lyubimova ◽  
V. N. Monastyrskii ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Low Temperature ◽  
Vinyl Acetate ◽  
Diesel Fuel ◽  
Low Molecular Weight

scholarly journals Fractionation of lignosulphonates released during the early stages of delignification

1983 ◽  
Vol 61 (2) ◽  
pp. 416-420 ◽  
Author(s):  
Norman G. Lewis ◽  
David A. I. Goring ◽  
Alfred Wong
Keyword(s):  
Molecular Weight ◽  
High Performance ◽  
Black Spruce ◽  
Gel Permeation Chromatography ◽  
Bimodal Distribution ◽  
High Yield ◽  
Low Molecular Weight ◽  
Lower Yield ◽  
Spruce Wood ◽  
Gel Permeation

High-yield spent bisulphite liquor (HY-SBL) from sulphonated black spruce wood (Piceamariana) was fractionated by gel permeation chromatography (GPC) and by high-performance liquid chromatography (HPLC). The GPC fractionation gave a wide bimodal distribution, whereas with HPLC, a more detailed resolution was seen with the bulk of the fraction giving several clearly defined peaks. The paucidisperse material was further concentrated by a bulk fractionation of the crude SBL which included complexing the lignosulphonates with dicyclohexylamine. The isolated paucidisperse material was found to be dialyzable and to constitute 90% of the lignosulphonate in the sample of SBL. If the bisulphite pulp obtained was recooked in fresh acid sulphite liquor to a lower yield, most of the lignosulphonate dissolved was widely polydisperse with no indication of the discrete components resolvable by HPLC. However, 25% of the lignin made soluble was in the form of the paucidisperse fractions. In all, we were able to obtain about 50% of the lignin in spruce wood as a relatively low molecular weight lignosulphonate resolvable into discrete fractions by HPLC.

High Yield Stress Associated with Capillary Attraction between Alumina Surfaces in the Presence of Low Molecular Weight Dicarboxylic Acids

Langmuir ◽  
2010 ◽  
Vol 26 (5) ◽  
pp. 3067-3076 ◽  
Author(s):  
E-Jen Teh ◽  
Yee-Kwong Leong ◽  
Yinong Liu ◽  
Vincent S. J. Craig ◽  
Rick B. Walsh ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Yield Stress ◽  
Dicarboxylic Acids ◽  
High Yield ◽  
Low Molecular Weight ◽  
High Yield Stress ◽  
Capillary Attraction

A Fluorescence Probe Study of Low Molecular Weight Poly(Methallyl Sulfonate-Vinyl Acetate) Copolymers

1992 ◽  
Vol 29 (8) ◽  
pp. 689-698 ◽  
Author(s):  
M. Tiera ◽  
M. G. Neumann ◽  
S. G. Bertolotti ◽  
C. M. Previtali
Keyword(s):  
Molecular Weight ◽  
Vinyl Acetate ◽  
Fluorescence Probe ◽  
Low Molecular Weight

Biosynthesis of Low Molecular Weight Bacterial Cellulose

2006 ◽  
Vol 309-311 ◽  
pp. 497-502 ◽  
Author(s):  
Yu Hong Feng ◽  
Xi Bin Wang ◽  
Qiang Lin ◽  
Zhou Xin Wu ◽  
Su Juan Pang ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Bacterial Cellulose ◽  
Culture Medium ◽  
Ph Value ◽  
High Yield ◽  
Low Molecular Weight ◽  
Culture Temperature ◽  
Culture Time ◽  
N Compounds ◽  
Medium Culture

The biosynthesis of low molecular weight bacterial cellulose (LMBC) by Static culture of Acetobacter xylinum HN001 has been investigated. The medium was prepared with coconut-water by adding sugar and N-compounds. Several conditions effected LMBC yields, such as start pH value of culture medium, culture temperature and culture time were investigated. In view of high yield of LMBC, the optimal culture time and culture temperature was about 70 hours and 32°C with yield of LMBC 1.2g/L. Molecular weight (MW) and molecular weight distribution (MWD) of LMBC were tested by GFC. Results showed that, though the start pH value of culture medium varied from 3.5 to 5.5, the MW of the product cellulose varied not notable and MWD of LMBC were all almost 1.3.

Sign in / Sign up

Export Citation Format

Share Document