Water sorption and transport in blends of polyethyloxazoline and polyethersulfone

Schult, K. A.; Paul, Donald R

doi:10.1002/(sici)1099-0488(19970430)35:6<993::aid-polb13>3.0.co;2-a

Cited by 27 publications

(20 citation statements)

References 3 publications

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“…For all four polymers, absorption and desorption data overlap at high activities, whereas they form a hysteresis loop at low activities; the amount of solvent in each polymer film is larger during the desorption process than that during the sorption process at the same water activity. A similar absorption/desorption hysteresis has been observed for several glassy water/polymer42–46 and organic solvent/polymer mixtures 47–49. We believe that the deviation of the desorption data from the sorption data is connected to a rubber‐to‐glass transition occurring during water‐vapor absorption/desorption.…”

Section: Resultssupporting

confidence: 78%

Sorption kinetics and equilibrium uptake for water vapor in soft‐contact‐lens hydrogels

Weinmüller

Langel

Fornasiero

et al. 2006

J Biomedical Materials Res

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A gravimetric-sorption technique was used to obtain kinetic and equilibrium adsorption/desorption data for water vapor in four different soft-contact-lens (SCL) polymers at 35 degrees C. The SCL materials are a conventional hydrogel (polymacon) with a low water content at saturation (<50 wt %); two conventional hydrogels (hilafilcon A and alphafilcon A) with a high water content at saturation (>50 wt %); and a siloxane hydrogel (balafilcon A). Absorption and desorption equilibrium isotherms (water activity versus water weight fraction) overlap at high water contents, whereas significant hysteresis is observed at low water contents. The hysteresis loop is likely due to trapping of water in the polymer during the desorption process because of a rubber-to-glass transition of the SCL-film surfaces. Sorption data were interpreted using Flory-Rehner theory. The positive Zimm and Lundberg cluster function suggests that water tends to cluster in these SCL materials, except at very low water content. For polymacon and hilafilcon A, Fickian diffusion is observed for all activities for both water sorption and desorption. However, for alphafilcon A and balafilcon A, non-Fickian features appear at intermediate/low activities, in particular during water desorption, suggesting coupling of the diffusion process with polymer-matrix relaxation. The diffusion coefficient increases significantly with water concentration for polymacon and hilafilcon A (from approximately 0.3 x 10(-8) to 4.0 x 10(-8) cm2/s) because of augmented mixture free volume induced by water sorption, whereas a more complex composition dependence is observed for alphafilcon A and balafilcon A probably as consequence of a combined effect of polymer relaxation, plasticization, and water clustering.

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Section: Resultssupporting

confidence: 78%

Sorption kinetics and equilibrium uptake for water vapor in soft‐contact‐lens hydrogels

Weinmüller

Langel

Fornasiero

et al. 2006

J Biomedical Materials Res

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“…The polymer membranes were more stable at a lower region, whereas the membranes were more affected by the membrane swelling and plasticization induced by the sorbed water molecules at a higher region. Permanent gases (i.e ., H 2 , O 2, N 2 , and CO 2 ) that did not strongly interact with the polymer generally showed increased solubility with increased free volume of polymer, which can be expected theoretically . PI, PSF, PA, OH‐containing Ad, PSF + PVP, PES + PEOX, and SUPI exhibited an opposite trend at low and high pressures because the membrane structure changed (i.e., increased FFV ), such as membrane swelling and plasticization.…”

Section: Resultssupporting

confidence: 54%

“…Furthermore, Paul et al . reported that hydrophilic polymer with high glass‐transition temperature tended to increase the amount of sorption sites of water compared with hydrophilic polymer having a low glass‐transition temperature . Based on these results, the sorbed water in hydrophilic polyimide component and the effect of high mobility of methacrylate chain in the PMAdMA component tended to decrease the glass‐transition temperature of Block(61/39).…”

Section: Resultsmentioning

confidence: 85%

“…For comparison, Figures and present the relationship between water vapor solubility at low and high pressures in each polymer membranes as a function of FFV with some series of polymer‐family membranes, such as polyimides, polysulfones (PSF), polyarylates (PA), and adamantane‐containing methacrylate polymers (Ad) [Figure (a,b)], as well as composition polymer membranes, such as PSF + poly(vinyl pyrrolidone) (PVP), polyethersulfone (PES)+polyethyloxazoline (PEOX), and sulfonated polyimide (SUPI) [Figure (a,b)]. Solubility at low and high pressures was given focus to investigate the effect of membrane swelling and plasticization.…”

Section: Resultsmentioning

confidence: 99%

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Phototransparency and water vapor sorption properties of ABA‐type triblock copolymers derived from 6FDA‐TeMPD and poly(2‐methyl‐2‐adamantylmethacrylate)

Ando

Konishi

Yoshida

et al. 2016

J of Applied Polymer Sci

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The phototransparency and water vapor sorption properties of ABA-type triblock copolymer membranes derived from 4,4-(hexafluoroisopropylidene) diphthalic anhydride-2,3,5,6-tetramethyl-1,4-phenylenediamine (PI) and poly(2-methyl-2-adamantylmethacrylate) (PMAdMA) were investigated, with focus on the effect of the adamantane component. The phototransparency of PMAdMA-block-PI-block-PMAdMA [Block(PI/PMAdMA)] was about 10-20% higher than that of poly(methyl methacrylate)-block-PI-block-Poly(methylmethacrylate) [Block(PI/PMMA)] because the high symmetric structure of adamantane inhibited photoabsorbance. The water vapor solubility of Block(PI/PMAdMA) decreased with increased PMAdMA because the PMAdMA had a hydrophobic property. Interestingly, in all relative-pressure regions, Block(PI/PMAdMA) with the least PMAdMA content showed a higher solubility coefficient than PI because the high mobility of PMAdMA in Block(PI/PMAdMA) resulted in additional sorption sites in the PI segment. A comparison of Block(PI/PMAdMA) with Block(PI/PMMA) in terms of relative pressure at the beginning of clustering further revealed that cluster formation in Block(PI/PMAdMA) was inhibited compared with Block(PI/PMMA) because bulky structure of adamantane restricted the mobility of the polymer main chain. V C 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43795.

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“…The chemical structures and the physical properties of a large number of water vapor transport properties in a series of family polymers, polymer blends, and copolymers have been investigated [6][7][8][12][13][14][15][16][17][18]. However, studies on the effects of the hydrophilic OH group on the hydrophobic polymers focusing on the chemical structure have not been conducted.…”

Section: Introductionmentioning

confidence: 76%

Effect of OH group on the water vapor sorption property of adamantane-containing polymer membranes

Kanehashi

Konishi

Takeo

et al. 2013

Journal of Membrane Science

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Water sorption and transport in blends of polyethyloxazoline and polyethersulfone

Cited by 27 publications

References 3 publications

Sorption kinetics and equilibrium uptake for water vapor in soft‐contact‐lens hydrogels

Sorption kinetics and equilibrium uptake for water vapor in soft‐contact‐lens hydrogels

Phototransparency and water vapor sorption properties of ABA‐type triblock copolymers derived from 6FDA‐TeMPD and poly(2‐methyl‐2‐adamantylmethacrylate)

Effect of OH group on the water vapor sorption property of adamantane-containing polymer membranes

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