Effect of Side-Chain on Conformation of Poly(acrylic acid) and Its Dielectric Behaviors in Aqueous Solution: Hydrophobic and Hydrogen-Bonding Interactions and Mechanism of Relaxations

2013 ◽  
Vol 117 (39) ◽  
pp. 11843-11852 ◽  
Author(s):  
Jingliang Li ◽  
Kongshuang Zhao
Keyword(s):  
Aqueous Solution ◽  
Hydrogen Bonding ◽  
Acrylic Acid ◽  
Side Chain ◽  
Hydrogen Bonding Interactions ◽  
Poly Acrylic Acid

A Proton-Exchange Poly (acrylic acid) Supramolecular Hydrogel for Ultrahigh Uranium Adsorption

2021 ◽  
Author(s):  
Zhongkuan Sun ◽  
Yongyi Chen ◽  
Yan Liu ◽  
Bing Na ◽  
Cheng Meng ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Acrylic Acid ◽  
High Efficiency ◽  
Proton Exchange ◽  
Cross Linking ◽  
Supramolecular Hydrogel ◽  
Uranium Adsorption ◽  
Hydrogen Bonding Interactions ◽  
Poly Acrylic Acid

Development of high-efficiency absorbents is ongoing demand to purify uranium-containing wastewater. This study reports a poly (acrylic acid) (PAA) supramolecular hydrogel with hydrogen bonding interactions via physical cross-linking in acidic...

scholarly journals Thermo-Responsive Behavior of Mixed Aqueous Solution of Hydrophilic Polymer with Pendant Phosphorylcholine Group and Poly(Acrylic Acid)

Polymers ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 148
Author(s):  
Hirokazu Fukumoto ◽  
Kazuhiko Ishihara ◽  
Shin-Ichi Yusa
Keyword(s):  
Aqueous Solution ◽  
Acrylic Acid ◽  
Solution Temperature ◽  
Interpolymer Complex ◽  
Mixed Aqueous Solution ◽  
Upper Critical Solution Temperature ◽  
Acidic Conditions ◽  
Decreasing Ph ◽  
Increasing Temperature ◽  
Poly Acrylic Acid

A mixed aqueous solution of hydrophilic poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) and poly(acrylic acid) (PAAc) becomes cloudy under acidic conditions at room temperature. The pendant carboxylic acid groups in PAAc form hydrogen bonds with the ester and phosphate groups in PMPC. While the polymers aggregate under acidic conditions, neither one associate under basic conditions because of the deprotonation of the pendant carboxy groups in PAAc. We observed that the interpolymer complex formed from PMPC, and PAAc was dissociated in aqueous solutions with increasing temperature, which is an upper critical solution temperature behavior. With increasing temperature, the molecular motion increased to dissociate the interpolymer complex. The phase transition temperature increased with increasing polymer and salt concentrations, and with decreasing pH.

Determination of the complexation properties of a crosslinked poly(acrylic acid) gel with copper(II), nickel(II), and lead(II) in dilute aqueous solution

2001 ◽  
Vol 79 (4) ◽  
pp. 370-376 ◽  
Author(s):  
Catherine Morlay ◽  
Yolande Mouginot ◽  
Monique Cromer ◽  
Olivier Vittori
Keyword(s):  
Aqueous Solution ◽  
Ionic Strength ◽  
Acrylic Acid ◽  
Metal Ion ◽  
Conditional Stability ◽  
Binding Properties ◽  
Complex Species ◽  
Complexing Capacity ◽  
Dilute Aqueous Solution ◽  
Poly Acrylic Acid

The possible removal of copper(II), nickel(II), or lead(II) by an insoluble crosslinked poly(acrylic acid) was investigated in dilute aqueous solution. The binding properties of the polymer were examined at pH = 6.0 or 4.0 with an ionic strength of the medium µ = 0.1 or 1.0 M (NaNO3) using differential pulse polarography as an investigation means. The highest complexing capacity of the polyacid was obtained with lead(II) at pH = 6.0 with µ = 0.1 M, 4.8 mmol Pb(II)/g polymer. The conditional stability constants of the complex species formed were determined using the method proposed by Ruzic assuming that only the 1:1 complex species was formed; for lead(II) at pH = 6.0 and µ = 0.1 M, log K' = 5.3 ± 0.2. It appeared that the binding properties of the polymer increased, depending on the metal ion, in the following order: Ni(II) < Cu(II) < Pb(II). The complexing capacity and log K' values decreased with the pH or with an increase of the ionic strength. These results were in agreement with the conclusions of our previous studies of the hydrosoluble linear analogues. Finally, with the insoluble polymer, the log K' values were comparable to those previously obtained with the linear analogue whereas the complexing capacity values expressed in mmol g-1 were slightly lower.Key words: insoluble crosslinked poly(acrylic acid), copper(II), nickel(II), and lead(II) complexation.

The significance of the Cα substituent in the selective inhibition of matrix metalloproteinases 1 and 9

2011 ◽  
Vol 392 (11) ◽  
Author(s):  
Riyad Domingo ◽  
Kelly Chibale ◽  
Edward D. Sturrock
Keyword(s):  
Hydrogen Bonding ◽  
Matrix Metalloproteinases ◽  
Active Sites ◽  
Unsaturated Compound ◽  
Selective Inhibition ◽  
Acid Group ◽  
Side Chain ◽  
Carboxylic Acid Group ◽  
Lead Compounds ◽  
Hydrogen Bonding Interactions

Abstract Matrix metalloproteinases (MMPs) cleave and degrade most components of the extracellular matrix, and unregulated MMP activity has been correlated to cancer and metastasis. Hence there is a burgeoning need to develop inhibitors that bind selectively to structurally similar MMPs. The inhibition profiles of peptidomimetics containing Cα substituents at the α,β unsaturated carbon were evaluated against the recombinant forms of ADAM17, MMP1, and MMP9. The dicarboxylic acid D2 and hydroxamate C2 inhibited MMP9 but not MMP1. The unsaturated compound E2 displayed selective inhibition for MMP1, compared with the saturated precursor C2, with an IC50 value of 3.91 μm. The molecular basis for this selectivity was further investigated by the molecular docking of E2 and D2 into the active sites of MMP1 and MMP9. These data demonstrate hydrogen-bonding interactions between the carbonyl group of the Cα substituent of E2 and the side chain of Asn180 present in the active site of MMP1. Conversely, the docked MMP9-D2 structure shows hydrophobic and hydrogen bonding between the ligand’s morpholine substituent and second carboxylic acid group with Leu187 and an amide, respectively. This study suggests that substituents other than P1′ and P2′ may confer selectivity among MMPs and may aid in the search for novel lead compounds.

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