Water-soluble copolymers: 22. Copolymers of acrylamide with 2-acrylamido-2-methylpropanedimethylammonium chloride: Aqueous solution properties of a polycation
“…Therefore, ethylamide, a monosubstituted amide, can be a hydrogen bond donor or acceptor depending on the environment. Because the dimethylamino group in DMAEMA is known to be a powerful hydrogen bond acceptor, it is reasonable to suggest efficient hydrogen bondings between ethylamide and N , N -dimethylamino groups. 2 N−H stretching region of the infrared spectrum of (A) polyDMAEMA, (B) copolymer I, (C) copolymer II, and (D) copolymer III.…”
The pH/temperature-induced phase transition of
poly((N,N-dimethylamino)ethyl
methacrylate (DMAEMA)-co-ethylacrylamide (EAAm)) was investigated.
Although polyDMAEMA and polyEAAm
were reported to exhibit a lower critical solution temperature (LCST)
at 50 and 80 °C, respectively, a
LCST shift from 50 to 4 °C was observed with copolymers of DMAEMA
with EAAm, and this behavior
was quite different at pH 4.0 and 7.4. This is due to the
formation of hydrogen bonding between DMAEMA
and EAAm residues with a hydrophobic contribution to the LCST. To
apply this polymer system to
glucose-controlled insulin release, a molded matrix consisting of
poly(DMAEMA-co-EAAm), glucose
oxidase, and insulin was prepared. This matrix exhibited a rapid
change from insolubility to solubility
when exposed alternately to solutions with ions and a high glucose
concentration, resulting in glucose-controlled insulin release.
“…Therefore, ethylamide, a monosubstituted amide, can be a hydrogen bond donor or acceptor depending on the environment. Because the dimethylamino group in DMAEMA is known to be a powerful hydrogen bond acceptor, it is reasonable to suggest efficient hydrogen bondings between ethylamide and N , N -dimethylamino groups. 2 N−H stretching region of the infrared spectrum of (A) polyDMAEMA, (B) copolymer I, (C) copolymer II, and (D) copolymer III.…”
The pH/temperature-induced phase transition of
poly((N,N-dimethylamino)ethyl
methacrylate (DMAEMA)-co-ethylacrylamide (EAAm)) was investigated.
Although polyDMAEMA and polyEAAm
were reported to exhibit a lower critical solution temperature (LCST)
at 50 and 80 °C, respectively, a
LCST shift from 50 to 4 °C was observed with copolymers of DMAEMA
with EAAm, and this behavior
was quite different at pH 4.0 and 7.4. This is due to the
formation of hydrogen bonding between DMAEMA
and EAAm residues with a hydrophobic contribution to the LCST. To
apply this polymer system to
glucose-controlled insulin release, a molded matrix consisting of
poly(DMAEMA-co-EAAm), glucose
oxidase, and insulin was prepared. This matrix exhibited a rapid
change from insolubility to solubility
when exposed alternately to solutions with ions and a high glucose
concentration, resulting in glucose-controlled insulin release.
“…Intrinsic viscosity is generally accepted to be an effective measure of the hydrodynamic volume of the polymers containing the same molecular weight. − Therefore, determining the intrinsic viscosity of poly(SDMPAPS)/NA in the presence of different salts should reflect the influence of these salts on the hydrodynamic volume of the polymer chain for poly(SDMPAPS)/NA. The intrinsic viscosity, [η], of the dilute solutions of polyelectrolyte can usually be calculated by the Huggins equation. ,, …”
Section: Resultsmentioning
confidence: 99%
“…Intrinsic viscosity is generally accepted as an effective measure of the hydrodynamic volume of polymers with the same molecular weight. , Therefore, determining the intrinsic viscosity of poly(SDMPAPS)/NA in the presence of different salts should reflect the influence of these salts on the hydrodynamic volume of the polymer chain for poly(SDMPAPS)/NA. The intrinsic viscosity, [η], of the dilute solutions of polyelectrolyte can usually be calculated by the Huggins equation. ,, The data reveal an increase in the intrinsic viscosity of poly(SDMPAPS)/NA in 0.1 M aqueous salt solution in the order KF < KCl < KBr < KI (different electrolytes with common cation K + ), LiCl < NaCl < KCl < RbCl < CsCl (different electrolytes with common anion Cl - ) and MgCl 2 < CaCl 2 < SrCl 2 < BaCl 2 (different electrolytes with divalent cations; Table ). These phenomena are the same as those of the corresponding naphthalene-labeled acrylamide-sulfobetaine copolymer [poly(ADMMAPS)/NA] …”
The photophysical and solution properties of
naphthalene-labeled styrene/N,N-dimethyl
maleimido
propylammonium propane sulfonate copolymer, poly(SDMPAPS)/NA, were
studied in terms of fluorescence,
cloud point, and viscosity measurements. The ratio of intensities
of the excimer and monomer fluorescence
(I
E/I
M) was shown as a
function of polymer concentration in deionized water. The value of
I
E/I
M
decreases
with an increase in the salt concentration. The addition of
anionic surfactants to the aqueous solution
of poly(SDMPAPS)/NA can either induce or break the interpolymer
aggregation. When the electrolyte
concentration increases, the Stern−Volmer quenching constant
(K
sv) also increases. The phase
behavior
of poly(SDMPAPS)/NA shows an upper critical solution temperature
around 17 °C. The intrinsic viscosity
of the poly(SDMPAPS)/NA in the presence of different salts
reflects the influence of these salts on the
hydrodynamic volume of the polymer chain for poly(SDMPAPS)/NA.
A model of the interaction between
poly(SDMPAPS)/NA and surfactant in aqueous solution is
proposed.
“…The intrinsic viscosity [g] of dilute solutions of polyelectrolyte can usually be calculated by the Huggins equation. 28,37,38 The data in this study show that in the dilute solution regime in various salts, even at high added salt concentrations, there is an up-turn in reduced viscosity that in a typical polyelectrolyte would be attributed to the ionization and subsequent repulsion of the ionic groups attached to the chain backbone. These phenomena were also observed by Pei †er and Lundberg, Salamone and co-workers,14,17, C by extrapolating the curves to zero concentration.…”
Section: Measurement Of the Viscosity Of Poly(admmaps)/namentioning
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