Effect of electrostatic interactions on phase transition in the swollen polymeric network

Ilavský, M.

doi:10.1016/0032-3861(81)90387-6

Cited by 112 publications

(50 citation statements)

References 10 publications

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“…2. a nervous pulse promotes ionic interchanges between the myofibril and the surrounding in a few microseconds. 3 . the free energy of AlP hydrolysis drives conformational changes in the myosin head resulting in the net movement of myosin along the actin filament 4. the movement occurs through the formation of complexes between two macromolecules ( myosin and actm) and an ion, ATP, and the subsequent dissociation ofthose complexes with formation of ADP.…”

Section: Life and Movement Eukariotic Musclesmentioning

confidence: 95%

“…A great advance in the understanding of chemomechanical systems was done few years later, when Flory (2) proposed an equation of state for equilibrium swelling of gels. It consists of four terms: a rubber-like elasticity term, a mixing entropy term, a polymer-solvent interaction term and an osmotic pressure term due to free counterions (3). The gel volume is, as well, influenced by temperature, the kind of solvent, the free ion concentration, the degree of crosslinking and the degree of dissociation of groups on polymer chains.…”

Section: Approach Through Electrochemical Systemsmentioning

confidence: 99%

See 1 more Smart Citation

<title>Artificial muscles working in aqueous solutions or in air</title>

Otero

Cantero

Sansiñena³

et al. 1999

SPIE Proceedings

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Macroscopic electrochemomechanicaldevices formed by bilayers or triple layers between electroactive polymers and a non conducting, adherent and flexible poplymer, able to describe angular movements in liquid electrolytes under electrochemical control are presented. Using a polymeric electrolyte, able to conduct ions, sandwiched between two polypyrrole layers, a muscle working in air was constructed. Any of those devices work under electrochemical control of the conformational changes occuring in polymeric chains. They act simultaneously as actuators and sensors. Similitudes with natural muscles are underlined.

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Section: Life and Movement Eukariotic Musclesmentioning

confidence: 95%

Section: Approach Through Electrochemical Systemsmentioning

confidence: 99%

<title>Artificial muscles working in aqueous solutions or in air</title>

Otero

Cantero

Sansiñena³

et al. 1999

SPIE Proceedings

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“…In the Flory-type swelling model, the swelling pressure of a gel is assumed to be sum of three contributions [23].…”

Section: Swelling Characteristics Of the Gelsmentioning

confidence: 99%

Crosslinked DADMAC polymers as cationic super absorbents

Korpe

Erdoğan

Bayram

et al. 2009

Reactive and Functional Polymers

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“…1 -3 For comparison of swelling results with theory, we use our generalized model in which the effects of repulsion of charges on the chain and finite chain extensibility are included. 3 In this model, all molecular parameters are independently accessible. This theory semiquantitatively describes collapse in water/ acetone mixtures and aqueous NaCl solutions of various charged gels.…”

Section: Comparison Of Swelling Data With the Theory Of Polyelectrolymentioning

confidence: 99%

“…We consider that polyelectrolyte gel is immersed in a solution of a uni-univalent salt (e.g., NaCl solution) so that, 3 where M 0 is molecular weight of the monomeric unit, i molar ratio of the number of charges bound to the chain to number of monomeric units (ionization) and c_ and f-, respectively, are concentrations of co-ions and activity coefficient (for f _ we use f _ = 0.66-0.13 log c, but the highest admissible value is f _ = 1, see ref 3).…”

Section: Comparison Of Swelling Data With the Theory Of Polyelectrolymentioning

confidence: 99%

Phase Transition in Swollen Gels XXVIII. Swelling and Mechanical Behavior of Poly(1-vinyl-2-pyrrolidone-co-N-vinylcaprolactam) Gels in Water/Acetone Mixtures

Ilavský

Mamytbekov

Sedláková

et al. 2001

Polym J

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ABSTRACT:Networks of statistical copolymers of 1-vinyl-2-pyrrolidone and N-vinylcaprolactam (molar ratios of VPNCL= 1/0, 0.8/0.2, 0.6/0.4, and 0.5/0.5) with ionic comonomer, N,N-dimethyl-N,N-diallylammonium chloride (mole fractions x8 =0, 0.03, and 0.05) and crosslinker, 1-1'-divinyl-3,3'-(ethane-1,1-diy])di(1-vinyl-2-pyrrolidone), were prepared by radiation polymerization in a water/ethanol mixture (H20/EtOH = 0.5/0.5 by vol.). Swelling and mechanical behavior was investigated in water/acetone (w/a) mixtures. For charged copolymers, a first-order phase transition (collapse) was found. The extent of collapse (stepwise change in the gel volume), 1' >, and critical acetone concentration in the mixture at collapse, a" slightly increase with content ofVCL and ammonium salt in gels. Shift of transition to higher a, is caused by increasing hydrophobicity of network chains with VCL content. Decrease in swelling with increasing acetone concentration in w/a mixtures is accompanied by increase in equilibrium modulus, so that mechanical behavior is predominantly determined by swelling. The theory of swelling equilibria of polyelectrolyte networks, in which the effects of electrostatic interactions of the charges on the chain and finite chain extensibility are included, semiquantitatively describes the swelling data provided an effective concentration of charges (lower than x,) was introduced.KEY WORDS First-Order Phase Transition I 1-Vinyl-2-pyrrolidone I N-Vinylcaprolactam Copolymers I Polyelectrolytes I Swelling Equilibria I Mechanical Behavior I Collapse Phenomenon I One advantage of hydrogels consists in capability of high swelling and exhibiting first-order phase transition (collapse) caused by small change in external conditions such as temperature, electric field, solvent compositions etc. 1 The presence of charges on the chain ( 1-10 mol%) seems to be an important condition for the occurrence of a jump change in gel volume. 2 -4 Most results were obtained with charged networks of polyacrylamide (gels sensitive to solvent composition) or with networks of ionic poly(N,N-diethylacrylamide) and charged poly (N-isopropylacrylamide) (temperature sensitive hydrogels). This transition, in particular temperature-induced collapse, can be widely used. 5 lapse in poly(N-isopropylacrylamide) hydrogels, report that while incorporation of a hydrophilic comonomer leads to higher transition temperature (LCST), incorporation of a hydrophobic monomer lowers transition temperature. This work investigates the effects of composition of ionized networks of statistical copolymers of 1-vinyl-2-pyrrolidone)/N-vinylcaprolactam (VPNCL) prepared by radiation polymerization in water/ethanol mixture (H20/EtOH=0.5/0.5 by vol.) on swelling and mechanical behavior in water/acetone (w/a) mixtures at room temperature. VCL is a more hydrophobic component due to the higher number of CH2 groups than in VP. Progressive interest in hydrogels based on poly(1-vinyl-2-pyrrolidone) (PVP) and copolymers can be found in recent literature. 6 -8 This interest is...

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Effect of electrostatic interactions on phase transition in the swollen polymeric network

Cited by 112 publications

References 10 publications

<title>Artificial muscles working in aqueous solutions or in air</title>

<title>Artificial muscles working in aqueous solutions or in air</title>

Crosslinked DADMAC polymers as cationic super absorbents

Phase Transition in Swollen Gels XXVIII. Swelling and Mechanical Behavior of Poly(1-vinyl-2-pyrrolidone-co-N-vinylcaprolactam) Gels in Water/Acetone Mixtures

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