49 research outputs found

    Hydration and Dehydration of Poly (Acrylic Acid) Lithium Salts

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    Drying and water uptake of poly(acrylic acid)lithium salts with different degrees of neutralization were studied. The slowing down of drying speed in solid state was not due to Tg but due to the difficulty of the release of water molecule bound to two metal carboxylates or carboxyls. Though the equilibrium water uptake increased with increasing neutralization %, the slope of the plot above ca.3396 neutralization was greater than that below this neutralization %. The enhanced water uptake was explained by the appearance of vacant sites in octet coordination of lithium ion

    ポリアクリル酸塩の固相及び濃厚溶液における水和に関する研究

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    第1章 緒論 第2章 ポリアクリル酸塩の合成 第3章 ポリアクリル酸塩の濃厚溶液における部分モル体積 第4章 収着 第5章 重量法によるポリアクリル酸塩の結合水の定量 第6章 DSCによるポリアクリル酸塩の結合水の定量 第7章 結合水の存在状態-NMRによる検討Made available in DSpace on 2012-07-03T23:56:49Z (GMT). No. of bitstreams: 2 hiraoka1.pdf: 9225944 bytes, checksum: 96cc85da30757b4c4b2baeb900431295 (MD5) hiraoka2.pdf: 7486813 bytes, checksum: 67eff543252dc026512b6935d8469d10 (MD5) Previous issue date: 1991-02-2

    Hydration of Poly(acrylic Acid) Rubidium and Cesium Salts

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    Drying and water uptake of poly(acrylic acid) rubidium and cesium salts with different degrees of neutralization were studied. Though the equilibrium water. uptake increased with increasing neutralization %. the slope of the plot above ca. 45 % neutralization was greater than that below this neutralization %

    Density Measurements of Poly(Acrylic Acid) Potassium Salts

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    Density measurements of poly(acrylic acid) potassium salts (PAK) with different degrees of neutralization and water contents are presentea. The apparent partial molar volumes of polymer, V2, and the partial molar volumes of water, V1, were calculated from the densities. The values of V2 decreased with increasing water content and eventually leveled off. The values of V1, which at low water contents were much smaller than that of free water, increased with increasing water content and reached that of free water, showing consequently the appearance of free water. Before reaching the final value of free water, the data indicated the formation of primary and secondary hydration shells. The structure of primary, hydration was suggested to be of body-centered cubic coordination in which carboxyl oxygen atoms participate

    Syntheses and Characterization of Polymers Containing Nucleic Acid Bases

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    Two different types of the polymers containing nucleic acid bases in backbone or in pendant groups were prepared. The polymers of the first type were polyureas obtained by the polyaddition reaction of uracil and adenine with hexamethylene diisocyanate (HMDI). The second type, that is cationic polyurethanes containing nucleic acid bases in pendant groups, were obtained by Menschutkin reaction of halogenated derivatives of uracil and adenine with a linear polyurethane containing, tertiary nitrogen atoms which was based on HMDI and N-methyldiethanolamine. Base-base interactions were studied for the polymers by UV and NMR spectra. A relatively high value of hypochromicity, ca. 19%, was observed for the mixture of the ionic polyurethane with uracil pendant and herring sperm DNA. Complementary hydrogen bonding interaction was detected for the mixture of the ionic polyurethane with adenine pendant and that with uracil pendant. Nonthrombogenic character of the polymers was examined according to the modified Lee-White method. The ionic polyurethanes with adenine and uracil pendant exhibited fairly good anti-clotting property

    POLYMERIZATION OF o-VINYLPHENOL

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    The structure of the polymer of o-vinylphenol was studied. o-Vinylphenol(o-VP) was prepared by thermal decarbonization of o-cumaric acid which was obtained by hydrolysis of cumarin with sodium ethylate. Free radical and cationic polymerization of o-VP were carried out in bulk or in CH2Cl2 solution by using BPO, AIBN, BF3・OEt2, AlCl3, and TiCl4 as initiator. The polymers were reprecipitated by water from methanol solution and residual monomer was removed with dilute aqueous alkaline solution. The resulting polymers were white powder or viscous materials. The structure of the polymers were investigated by UV, IR, and NMR spectral measurement. UV spectra showed that the polymers have similar structures except for the one prepared by using BF3・OEt2. IR spectra showed the presence of methyl group and 1,2,4-trisubstituted benzene structure which are not expected from ordinary vinyl polymerization mechanism. The relative intensities of -CH3 and -CH2 group differ among polymers and suggested only the polymer prepared by using AIBN had relatively few -CH3 group. NMR spectral study supportedthe results obtained from IR spectra. The presence of -CH3 group was confirmed by C-methyl determination method (chromic acid oxidizing method) and the the amounts of C-CH3 groups were determined. From these results it was concluded that o-VP polymerizes through two different propagation steps, one is ordinary vinyl polymerization mechanism and the other the addition of vinyl group to pheno1ic nuclei

    北九州地域における着生蘇苔類の金属含有量

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    Metal contents in epiphytic bryophytes growing at Yahata Nishi-ku, Kitakyushu City and its vicinity were measured. Measurements were made both on the contents in the plant body of a single species Clastobryella kusatsuensis and on those of the whole bryophytic community. Contents of eight elements (Fe, Zn, Mn, Cr, Pb, Ni, Cu and Cd) decrease generally with increase in distance from the center of the industrialized area. No such marked regional difference was seen in the contents of Ca and Mg. The ratios of seven klnds of elements (Fe, Mn, Cr. Pb, Ni, Cu and Cd) in bryophytes almost coincide with those in airborne particulates. It was proved that C. kusatsuensis and communities of bryophytes can be an indicator of air pollution by metals.(Received 12 November 1982)高度開発地域での企属による環境治染を探る基礎資料を得る目的のため, 北九州市八幡西区とその周辺地域の着生薊苔類の体内金属量を, コモチイトゴケ1種および群落全体についで測定した. Fe, Zn, Mn, Cr, Pb, Ni, Cu, Cdの量は工業の中心地域から遠ざかる程減少する傾向を示したが, Ca, Mgは地域的な差が見られなかった. Fe, Mn, Cr, Pb, Ni, Cu, Cdの蘇苔類体内の含有量の比率は, 大気中の比率とほぼ一致した. コモチイトゴケ1種, 薊苔類群落全体について, 大気の金属汚染の生物指標となることが示唆された
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