Effects of Water on the Mobility of Nonionic Spin Probes in Nylon 6 Film

Hamada, Kunihiro; Iijima, T.; McGregor, R.

doi:10.1295/polymj.17.1245

Cited by 9 publications

(4 citation statements)

References 21 publications

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“…Rearrangement of eq 1 leads to eq 2. (2) As shown in Figure 1, the plot of CsfCP against Cs gave a straight line, supporting the Langmuir type sorption of the anionic probe molecule by the positively charged membrane. From the slope and intercept of the straight line, K and n were determined as 470 dm 3 mol-1 and 4 x 10-4 mo!…”

Section: Location Of the Spin Probes In The Membranessupporting

confidence: 69%

See 1 more Smart Citation

Mobility of Spin Probes in Quaternized Poly(4-vinylpyridine) Membranes

Yoshihiko

Hamada

Iijima

1987

Polym J

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ABSTRACT:The mobility of nonionic and anionic spin probes in water-containing quaternized poly(4-vinylpyridine) membranes was investigated by means of an electron spin resonance (ESR) technique. Poly(4-vinylpyridine) was quaternized and crosslinked by dibromoalkane Br(CH2).Br (n = 4, 6, 8, I 0), and the effects of the side alkyl chain length were studied. Three spin probes, 2,2,4,4-tetramethyl-1,2,3,4-tetrahydro-y-carboline-3-oxyl (SPII), 2,2,6,6-tetramethyl-lpiperidinyloxy (SPIV), and sodium 2,2,5,5-tetramethyl-l-pyrrolidinyloxy-3-carboxylate (ASP!), were used. In the temperature region examined, the side methylene chain length had no effect on the mobility of SPII and SPIV, but a little effect for ASPI. This suggests that the ASP! can monitor the mobility of the side alkyl chain. In addition, the effects of water on the mobility of the spin probes were investigated. The mobility of the spin probes was much greater in the membrane containing 30 wt% water than in that containing 3 wt% water, and the polarity around the probes was larger in the former than in the latter membrane. From this, as pointed out in our previous papers on nylon 6/spin probe systems, the effects of water are divided into (!) the effects on the mobilities of the polymer chains and probe molecules, and (2) the effects on the microenvironment around the spin probes. KEY WORDSSpin Probe / Nitroxide / Poly(4-vinylpyridine) / Molecular Motion / Water/ ESR / In the study of membrane transport phenomena, knowledge on the states of penetrants in membranes gives a clue to the mechanism of the transport involved. From this point of view, we investigated the mobilities of spin probes in nylon films by means of an electron spin resonance (ESR) technique. 1 -5 As a results, their mobilities increased with increasing methylene chain length of the nylon, and were strongly affected by water.measurements. P4VP has a high chemical reactivity which is due to its nucleophilic and weakly basic ring nitrogens. This reactivity makes it very attractive a material for a number of applications. 6 Recently quaternized P4VP membranes were applied to charged reverse osmosis membranes, and the dependence of the hydrodynamic permeability and the salt rejection on the charge density of the membrane was investigated. 7 In the present study, poly(4-vinylpyridine) (P4VP) membranes were prepared by quaternizing and crosslinking with dibromoalkane Br(CH 2 )"Br (n = 4,6,8,10), and the mobility of nonionic and anionic spin probes in these membranes was studied by means of ESR We focus our attention on the effects of the side methylene chain length and water on the mobility of the spin probes in the quaternized P4VP membranes. The effects of the side chain length on the mobility of 4-hydroxy-2,2,6,6-tetramethyl-l-piperidinyloxy in a series of * Present address:

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Section: Location Of the Spin Probes In The Membranessupporting

confidence: 69%

“…6,1987 resulting in an increase of 2Az'. 2 This effect shifts the curve vertically along the ordinate. The superposition of these two effects gives the curves shown in Figures 5 and 6.…”

Section: Extrema Separationmentioning

confidence: 99%

Mobility of Spin Probes in Quaternized Poly(4-vinylpyridine) Membranes

Yoshihiko

Hamada

Iijima

1987

Polym J

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“…12). [128][129][130] Water lowers the steric hindrance for the localized mode of dipolar orientation. 131 As a result, it weakens the interchain hydrogen bonds, enhances the mobility of the polymer chains, and dramatically affects the polymer properties; this includes lowering T g .…”

Section: Mechanism Of Hydrationmentioning

confidence: 99%

Hydrogen bonding, mobility, and structural transitions in aliphatic polyamides

Murthy

2006

J Polym Sci B Polym Phys

222

197

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Some salient results in nylon research are reviewed to identify the fundamental principles that are applicable to other strongly interacting or hydrogenbonded polymers, including proteins. The effects of hydrogen bonds on stress-, heat-, and solvent-induced changes in macroscopic properties are discussed. These data provide a window into the chain mobility and linkages between the crystalline and amorphous domains, both of which are important for any predictive model. The changes in the characteristics of the amorphous phase with the crystallinity and orientation require that it be modeled with at least two components: a rigid/immobile/ anisotropic component and a soft/ mobile/isotropic component. The deformation and shrinkage behavior of these polymers are discussed in terms of the relative contributions of the amorphous and crystalline domains and of the interactions between them. The premelting crystalline transition is accompanied by the merging of intersheet and intrasheet diffraction peaks in some nylons, as observed by Brill, and not in others even though the underlying mechanism that gives rise to these transitions, the onset of volume-increasing librational motion of the crystalline stems, is the same. Because the effects of the temperature, deformation, and solvent have a common origin associated with mobility, a fictive temperature can be associated with a given solvent activity or stress level. The magnitude of this fictive temperature is the amount by which the glass or Brill transition temperature is reduced in the presence of solvents ($50 8C) or stress or by which the annealing temperature can be reduced in the presence of a solvent (or active stress) to achieve the same structural state as that of a dry (or static) polymer.

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“…We have investigated the mobility of spin probes in nylon films by means of electron spin resonance (ESR) measurements. [1][2][3][4] The mobility was strongly affected by water in the nylon films,2,3 by drawing of the nylon films,4 and by the methylene chain length of the nylons. 4 In these studies we focused our attention on the interactions between the spin probes and the nylon chains and explained the above-mentioned effects on the basis of these interactions.…”

Section: Introductionmentioning

confidence: 99%