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Volume 43, Issue 11
Displaying 1-12 of 12 articles from this issue
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AND TEXTILES: PART VI. MEASUREMENT OF THE HEAT OF MOISTURE SORPTION BY A HEAT TRANSFER TYPE CALORIMETERMitsuhiro Fukuda, Kaneko Ohtani, Masami Iwasaki, Hiromichi Kawai1987 Volume 43 Issue 11 Pages 567-577
Published: November 10, 1987
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSThe heat of wetting W and further the differential heat of moisture sorption QL were observed as a function of moisture regain α for normal viscose rayon and nylon 6 fiber at 30°C by using a heat transfer type calorimeter in order to investigate the interaction of water with textiles in terms of thermodynamic parameters.
Critical value of W at dryness, W(α=0), was found to be 23.4±0.5 and 5.8±0.3 cal/gram of dry material, for the normal viscose rayon and the nylon 6 fiber, respectively. The differential heat of moisture sorption QL was determined from negative slope of empirical formula: i.e. QL(α)=-dW(α)/dα The critical value at dryness, QL(α=0), was found to be 273±4 and 218±18 cal/gram of liquid water for the respective specimens with good agreement with the reported values of these materials. The excess energy of the sorbed water, (TΔSL), was estimated to attain around 100 cal/gram of liquid water at dryness for both specimens, which is roughly equal to the latent heat of fusion of ice.
Another critical value of W at saturation regain, W(α=αs), which had been supposed to be zero by several authors, was found to be small in magnitude but definitely finite for both specimens. QL(α=αs) as well as (TΔSL) at saturation were also found to be finite, strongly suggesting the sorbed water, even near saturation, to be still in a little more ordered state than in the liquid state. All of these results confirms the heat transfer type calorimeter adopted here to be fully reliable for the determination of thermodynamic quantities in the moisture sorption process of the textile materials.View full abstractDownload PDF (755K) -
Ichiro Matsuno, Akira Takizawa, Takatoshi Kinoshita, Yoshiharu Tsujita1987 Volume 43 Issue 11 Pages 578-586
Published: November 10, 1987
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSThe flux equations for positive and negative directions in one dimensional flux through laminated membrane are constructed taking into account the concentration dependences of diffusion coefficient and solubility coefficient of penetrant in respective component layer, and the flux ratio about the two directions is calculated. The calculation is carried out in accordance with the experimental permeation results of laminated membranes of various combinations of hydrophilic and hydrophobic layers. The flux ratio shows the maximum at a certain relative vapor pressure. The vapor pressure which shows the maximum of flux ratio is analysed by the sorption and permeation behaviors of the component single membranes.View full abstractDownload PDF (506K) -
Wan Shik Ha, Sang Kyun Oh, Joon Ho Kim, Kea Yong Kim1987 Volume 43 Issue 11 Pages 587-594
Published: November 10, 1987
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSSilk fibroin (SF) and polyacrylic acid (PAA)-grafted silk fibroin were dissolved in calcium chloride/ethanol/water mixture (1/2/8 in mole ratio) at 70°C for 4 hrs. The dissolved silk fibroin and SF-g-PAA polymer were regenerated by casting the dialyzed solutions into the films, respectively. The freshly prepared silk fibroin film was soluble in water and mainly consisted of random coil structure. By treating with aqueous solutions of organic solvents, such as formic acid, trichloroacetic acid, and methanol, the silk fibroin was denatured into insoluble β-pleated sheet structure. The contact angles of silk fibroin and SF-g-PAA films were measured after treating the films with aqueous methanol solution. The surface tensions of the films were calculated in three dimensions consisting of dispersion, polar, and hydrogen bond components from the contact angle data by using determinant method. As IR crystallinity indices of silk fibroin films treated with solvents increased, the total surface tension, polar, and especially, hydrogen bond components increased linearly. However, the dispersion component was nearly independent of the IR crystallinity index of the film. On the other hand, in SF-g-PAA film, with increasing graft yield the total surface tension, polar and hydrogen bond components increased and the dispersion component decreased.View full abstractDownload PDF (540K) -
Shigeo Hirose, Kunio Nakamura, Tatsuko Hatakeyama, Hyoe Hatakeyama1987 Volume 43 Issue 11 Pages 595-601
Published: November 10, 1987
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSAromatic polyethers, polyether I and II were synthesized by the reaction of bis (4-fluorophenyl) phenylphosphine oxide (BFPO) with alkali salt of 2, 2-bis (4-hydroxyphenyl) propane and 4, 4′-dihydroxybiphenyl, respectively. The thermal properties of the polyethers were studied by differential scanning calorimetry (DSC) and thermogravimetry (TG). In order to establish the characteristics of the polymerization, the alkali metal was changed, along with other reaction conditions such as the temperature and the time were changed. It was found that the polymerization in dimethyl sulfoxide (DMSO) using potassium at 185°C gave polyether I and II having 0.64 and 0.48dl/g of inherent viscosity, respectively. X-ray diffractograms of those polyethers indicated typical halo patterns, suggesting that they were amorphous. The glass transition was observed in DSC measurements at 197°C for polyether I and 225°C for polyether II. TG measurements showed that polyether I and II started to decompose in nitrogen at 505°C and 535°C, respectively. The activation energies (E's) of thermal degradation were also determined using TG. The values of E's were 164 kJ/mol for polyether I and 217 kJ/mol for polyether II.View full abstractDownload PDF (441K) -
SYNTHESIS AND STRUCTURE DETERMINATION OF LEUCO-MONO AMINONAPHTHOQUINONE DERIVATIVES BASED ON NAPHTHAZARINMasashi Kikuchi, Motokiyo Nakano1987 Volume 43 Issue 11 Pages 602-607
Published: November 10, 1987
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSNovel compounds related to leuco-monoaminonaphthoquinones derived from naphthazarin were synthesized. These leuco-compounds were stable even in aerated solvents. Their structures in tautomeric isomers were definitely elucidated by 1H, 13C-NMR spectroscopies. The assignment of 13C-NMR was achieved by 1H, 13C long range selective proton decoupling (LSPD) method. The structure of leuco-compound of naphthazarin was confirmed to be 2, 3-dihydro-5, 8-dihydroxynaphthalene-1, 4-dione. The structures of leuco-compounds of 2-butylaminonaphthazarin and 5-butylamino-8-hydroxynaphthoquinone were revealed to be 6-butylamino-2, 3-dihydro-5, 8-dihydroxynaphthalene-1, 4-dione and 5-butylamino-2, 3-dihydro-8-hydroxynaphthalene-1, 4-dione, respectively.View full abstractDownload PDF (417K) -
Hideo Kusaoke, Shinpachi Iso, Kunihiko Hirose, Takehisa Sakurai, Kazuo ...1987 Volume 43 Issue 11 Pages 608-613
Published: November 10, 1987
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSAn immobilization method of enzyme in acylchitosan gel as a novel support, which was prepared by the reaction of chitosan with carboxylic anhydride in aqueous solution of carboxylic acid, was investigated. Invertase was immobilized in acylchitosan gel using the bifunctional agent, glutaraldeahyde. The most active preparation is based on the enzyme bound acetylchitosan gel with degree of substitution of acetyl groups of 1.05. Its activity yield was 37.7% after incubation at pH 4.2 for 20 min, using sucrose as substrate. The optimum pH was shifted to acidic side as the result of the immobilization. The optimal temperature of gel-immobilized enzyme was 60°C, and higher than that of native enzyme (50°C). The activity of gel bound enzyme through the column showed no significant drop even after being used over 20 days.View full abstractDownload PDF (383K) -
BINDING OF A NON-IONIC AZO DYE BY SODIUM SALT OF β-NAPHTHALENESULFONIC ACID-FORMALDEHYDE CONDENSATESEFFECT OF THE DEGREE OF THE CONDENSATION ON THE BINDING EQUILIBRIUMTakao Shibusawa1987 Volume 43 Issue 11 Pages 614-621
Published: November 10, 1987
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSThe binding of a model azo disperse dye by β-naphthalenesulfonic acid and formaldehyde condensates (βNSF) in water was discussed. The binding constants, K, for the bidding by βNSF with different degrees of condensation, N=2, 3, 4, 5, 7.2, 12 and 40 were determined spectrophothometrically. The thermodynamic parameters, the enthalpy change, ΔH° and the entropy change, ΔS° calculated from the values of K in the temperature range 15-40°C revealed following facts.
The value of K increases with N up to N=ca. 10 and then level off gradually. This is ascribed to an increase in ΔS° with N; the value is negative for βNSF with N=2, 3 and 4 but it becomes positive for βNSF with N=12, 40 under the low concentration of added salts. The value of ΔH° is negative irrespective of N but its absolute value decreases with the increase in N.
The increase in the concentration of added salts gives no appreciable change in the thermodynamic parameters for βNSF with N=3 but for βNSF with N=12 and 40, the increase gives significant changes in the parameters; both values of ΔH° and ΔS° decrease significantly. These results may be explained in terms of the conformational change of polyelectrolytes. βNSF with N=12 and 40 behave as a typical polyelectrolyte; their conformation varies from an expanded form to a compact one on addition of electrolytes. The extended conformation is favorable for the hydrophobic interaction between the linear dye and successive naphthalene nuclei of βNSF with a high degree of the condensation. The increase in the value of ΔS° with N may be explained in terms of the contribution of the hydrophobic bonding to the binding.View full abstractDownload PDF (469K) -
Yuji Kimura, Kunihiro Hamada, Toshiro Iijima1987 Volume 43 Issue 11 Pages 622-625
Published: November 10, 1987
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSThe rotational mobility of a cationic nitroxide spin probe in carboxyethyl cellulose, sulfoethyl cellulose and phosphoric cellulose membranes was investigated by electron spin resonance (ESR). The rotational motion of the probe was observed to be almost isotropic. The mobility of the probe in these membranes decreased to 30_??_50% of that in aqueous solution and was thought to be affected by the charge density and the state of water in the membranes. The rotational correlation time, τR, in water-swollen membranes was smaller than that in dried membranes by a factor of 103_??_104View full abstractDownload PDF (192K) -
YOSHIO IMAI, YOSHIYUKI OISHI1987 Volume 43 Issue 11 Pages P435-P441
Published: November 10, 1987
Released on J-STAGE: November 28, 2008
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MICHIHIKO TANAKA1987 Volume 43 Issue 11 Pages P442-P448
Published: November 10, 1987
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSDownload PDF (995K) -
YASUO KATO, YUHIKO YAMASHITA1987 Volume 43 Issue 11 Pages P449-P455
Published: November 10, 1987
Released on J-STAGE: November 28, 2008
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TAKESHI ENDO1987 Volume 43 Issue 11 Pages P456-P462
Published: November 10, 1987
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSDownload PDF (953K)
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