scholarly journals Effect of Molecular Weights of Poly(acrylic acid) on Crystallization of Calcium Carbonate by the Delayed Addition Method

2007 ◽  
Vol 40 (2) ◽  
pp. 154-162 ◽  
Author(s):  
Shu-Chen Huang ◽  
Kensuke Naka ◽  
Yoshiki Chujo
Keyword(s):  
Calcium Carbonate ◽  
Acrylic Acid ◽  
Addition Method ◽  
Molecular Weights ◽  
Poly Acrylic Acid

scholarly journals Effects Of Environmental Factors On The Dispersion Behavior Of Iron Oxide In Aqueous Solutions With Poly Acrylic Acid

2015 ◽  
Vol 60 (2) ◽  
pp. 1561-1564
Author(s):  
E.-H. Lee ◽  
K.-M. Kim ◽  
W.-Y. Maeng ◽  
D.-H. Hur
Keyword(s):  
Molecular Weight ◽  
Acrylic Acid ◽  
High Molecular Weight ◽  
Low Molecular Weight ◽  
Solution Ph ◽  
Molecular Weights ◽  
Aqueous Suspensions ◽  
Magnetite Particles ◽  
The Stability ◽  
Poly Acrylic Acid

Abstract After preparing aqueous suspensions from magnetite particles with a poly-acrylic acid, we investigated the effects of several experimental parameters. We characterized the stability of the suspensions using visual inspection, sedimentation, adsorption, and thermal stability of the dispersant. The dispersion stability is affected by the solution pH, the concentrations of magnetite particles, the molecular weight, the concentration of the dispersants, and the temperature. The stability of the suspensions increased as the concentration of the dispersant and the temperature increased. In terms of the molecular weights of the dispersant, the suspensions with dispersant of low-molecular weight (1800) were more stable than those of high-molecular weight (250000) at room temperature. However, at high temperature the suspensions with high-molecular weight showed stability. The adsorption efficiency of the dispersant was very low. The dispersant of high-molecular weight showed a higher thermal integrity than that of low-molecular weight. From this work, we obtained the optimum conditions for stable aqueous suspensions of magnetite particles.

Preparation of amorphous calcium carbonate nanoparticles from impure dolomitic marble with the aid of poly(acrylic acid) as a stabilizer

2014 ◽  
Vol 25 (2) ◽  
pp. 591-598 ◽  
Author(s):  
M.M.M.G.P.G. Mantilaka ◽  
R.M.G. Rajapakse ◽  
D.G.G.P. Karunaratne ◽  
H.M.T.G.A. Pitawala
Keyword(s):  
Calcium Carbonate ◽  
Acrylic Acid ◽  
Amorphous Calcium Carbonate ◽  
Dolomitic Marble ◽  
Poly Acrylic Acid

scholarly journals Antibacterial activity of chitosan and the interpolyelectrolyte complexes of poly(acrylic acid)-chitosan

2010 ◽  
Vol 53 (3) ◽  
pp. 623-628 ◽  
Author(s):  
Hortensia Ortega-Ortiz ◽  
Baltazar Gutiérrez-Rodríguez ◽  
Gregorio Cadenas-Pliego ◽  
Luis Ibarra Jimenez
Keyword(s):  
Antibacterial Activity ◽  
Acrylic Acid ◽  
Antimicrobial Agents ◽  
Water Soluble ◽  
Amino Groups ◽  
Molecular Weights ◽  
Carboxylic Acid Groups ◽  
Microbial Inhibition ◽  
Interpolyelectrolyte Complexes ◽  
Poly Acrylic Acid

The antimicrobial activity of chitosan and water soluble interpolyelectrolyte complexes of poly(acrylic acid)-chitosan was studied. Chitosans of two different molecular weights were tested at different concentration for 0.5 to 5 g·L-1 as antimicrobial agents against P. aeruginosa and P. oleovorans. In both cases, the best microbial inhibition was obtained with the concentration of 5 g·L-1. However, the interpolyelectrolyte complexes of poly(acrylic acid)-chitosan with composition φ =2 produced higher antibacterial activity than the two chitosans at the concentration of 0.5 g·L-1. The NPEC2 complex was more effective than chitosans. This could be attributed to the number of moles of the amino groups of chitosan and the carboxylic acid groups of the interpolyelectrolyte complexes poly(acrylic acid).

Synthesis and Characteristics of Interpenetrating Polymer Network Hydrogels Based on Konjac Glucomannan with Different Molecular Weights and Poly(acrylic acid)

2011 ◽  
Vol 393-395 ◽  
pp. 1004-1007
Author(s):  
Xue Yao ◽  
Xue Gang Luo ◽  
Ben Chao Han
Keyword(s):  
Acrylic Acid ◽  
Enzymatic Degradation ◽  
Drug Carrier ◽  
Polymer Network ◽  
Konjac Glucomannan ◽  
Interpenetrating Polymer Network ◽  
Swelling Ratio ◽  
Molecular Weights ◽  
Ft Ir ◽  
Poly Acrylic Acid

Konjac glucomannan with different molecular weights/poly(acrylic acid) hydrogels were prepared in this paper. The structure of the IPN hydrogels was characterized by FT-IR and SEM. The swelling ratio of these hydrogels showed they had pH-sensitive properties and the enzymatic degradation tests showed the hydrogels retain the enzymatic degradation character of KGM. Furthermore, hydrogel composed of native KGM degraded sharply in enzymatic degradation test and it had bigger swelling ratio and weight loss ratio than those hydrogels which composed of lower molecular weights KGM. Therefore, hydrogels composed of lower molecular weight might release drug more stable when they were used as drug carrier.

Crystallization of vaterite and aragonite on chitin whiskers

2021 ◽  
Vol 16 (2) ◽  
pp. 23-30
Author(s):  
Michael Ikpi Ofem
Keyword(s):  
Calcium Carbonate ◽  
Acrylic Acid ◽  
Room Temperature ◽  
Spherical Shape ◽  
Time Frame ◽  
Sem Images ◽  
Volume Fractions ◽  
Chitin Whiskers ◽  
Calcium Carbonate Polymorphs ◽  
Poly Acrylic Acid

The need for the possibility of producing calcium carbonate crystals by the evaporation method within five minutes and the growth of different calcium carbonate polymorphs on chitin whiskers within the same time frame at room temperature necessitated these report. Chitin whiskers (CHWs) were used as insoluble substrates, while poly (acrylic) acid (PAA) is used as soluble additive. The crystals were grown in chitin whiskers, Poly (acrylic) acid and CHW/PAA composites. The volume fractions for aragonite, vaterite, and calcite are 0.10, 0.25, and 0.65, respectively, in the absence of chitin whiskers or Poly (acrylic) acid. Calcite and aragonite volume fractions decrease in favour of vaterite when PAA and or CHWs were added. SEM images in the absence of CHWs and PAA shows rhombohedral calcites that display steady and step like plane appearances with an average edge of between 1.3 and 1.4 μm. In the presence of only CHWs, the SEM images show a mixture of ellipsoidal and spherical shape vaterites. The spherical vaterites have smooth, rough, and some irregular surfaces. Rod-like aragonite polymorphs were seen when only PAA was used as the template. In the presence of both PAA and CHWs, the rhombohedral shape showed roughness with irregular faces. Keywords: Chitin whisker, Calcium carbonate, Calcium, vaterite aragonite, Polymorph, Mole fraction

scholarly journals Synthesis of nanoporous calcium carbonate spheres using double hydrophilic block copolymer poly(acrylic acid-b-N-isopropylacrylamide)

2018 ◽  
Vol 230 ◽  
pp. 143-147 ◽  
Author(s):  
Sudhina Guragain ◽  
Nagy L. Torad ◽  
Yousef Gamaan Alghamdi ◽  
Abdulmohsen Ali Alshehri ◽  
Jeonghun Kim ◽  
...  
Keyword(s):  
Calcium Carbonate ◽  
Block Copolymer ◽  
Acrylic Acid ◽  
Copolymer Poly ◽  
Poly Acrylic Acid

Nanosized Amorphous Calcium Carbonate Stabilized by Poly(ethylene oxide)-b-poly(acrylic acid) Block Copolymers

Langmuir ◽  
2006 ◽  
Vol 22 (4) ◽  
pp. 1875-1879 ◽  
Author(s):  
Baptiste Guillemet ◽  
Michael Faatz ◽  
Franziska Gröhn ◽  
Gerhard Wegner ◽  
Yves Gnanou
Keyword(s):  
Calcium Carbonate ◽  
Block Copolymers ◽  
Acrylic Acid ◽  
Ethylene Oxide ◽  
Amorphous Calcium Carbonate ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene ◽  
Poly Acrylic Acid
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