巻号一覧
30 巻, 5-6 号
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赤堀 忠義, 林 治助, 渡辺 貞良1974 年 30 巻 5-6 号 p. T167-T178
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーThe fine structure in Rayon fibers is to be interplated more reasonably by the folded chain model than by the fringed micellar model. This paper presents the folded chain model with about 200Å period on the basis of the following experimental facts: 1) all the rayon fibers uniformly gave a Levelling-off DP of about 40, equivalent to about 200A, at the early stage of heterogeneous acid hydrolysis, 2) the crystallite length and the long period measured by the X-ray technique are about 200A without exception. 3) A family of GPC chromatogams of the hydrolysed cellulose exhibited a single peak, suggesting mono-disparsion.
The theoretical basis of this model has been demonstrated by the authers. Single cellulose molecule chain is essentially folded back and forth in the (101) plane to form a sheet-like structure to fit into the cellulose II lattice. A fairly sharp U-turn of a cellulose molecule at the fold is achieved with only one glucose unit of halfboat type. A crystallite is consisted of the sheet-like structure units which are held together by secondary forces between the units. In crystallographic registry, the crystallites are colsely packed at the surface of each fold in its longitudinal edges to make up the microfibril of Rayon.抄録全体を表示PDF形式でダウンロード (911K) -
赤堀 忠義, 林 治助, 渡辺 貞良1974 年 30 巻 5-6 号 p. T179-T189
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーIn the previous paper1) the possibility of molecular chain folding for cellulose molecule by accommodating in a molecular model and the fine structure in cellulose crystallite were discussed, and the folded chain model of Rayon was also presented on the ground of x-ray diffraction and acid hydrolysis studies.
In the present paper, the folded chain structure of the various cellulose modifications derived from native cellulose and rayon is discussed. All cellulose modifications can be interpreted as the same fine structure of rayon, which consists of the folded chain molecule with the basic period of about 200Å. However, the scheme of acid hydrolysis reaction of the most cellulose modifications from native cellulose differs from that of rayons: the molecular chains of cellulose I family are only hydrolyzed at each alternate folding part. Thus their levelling-off degrees of polymerization result in 80 corresponding to the chain length of about 400Å.
The difference between cellulose I and II family appears in the arrangements of a polarity of folded chains caused from a cellulose molecule itself. From the modeling consideration, there are two types in them: parallel and antiparallel. The former is resistant to acid, and the latter is accessible to acid. It is anticipated that the hydrogen bonding is only that of the latter type in cellulose II family and alternating the former and the latter types in cellulose I family.抄録全体を表示PDF形式でダウンロード (773K) -
林 治助, 山田 拓司, 渡辺 貞良1974 年 30 巻 5-6 号 p. T190-T198
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーIt was found that there was a difference between X-ray diffractograms of Na-Cellulose I derived from the cellulose I family (I and IIII) and that from the cellulose II family (II, IIIII and IVII), and we calssified them as Na-Cellulose II and Na-Cellulose III, respectively. Both Na-Cellulose II and III regenerated cellulose II by washing with cold water. When decomposed with hot water, however, Na-Cellulose II regenerated mixture of cellulose I and II, and Na-Cellulose III regenerated cellulose II. Namely, Na-Cellulose has memory of the crystalline structure of the original cellulose.
As described in our previous paper, the chain conformation of cellulose is thought to be a difference between cellulose I and II families, the former has “bent” type and the latter has “bent and twisted” type comformation.
The memory of the original structure may be due to the retaining of chain conformation during meroerization and regeneration. When Na-Cellulose II is decomposed by cold water, the chain conformation is changed from “bent” to more stable “bent and twisted” type owing to strong swelling and hydration, and cellulose II was regenerated.抄録全体を表示PDF形式でダウンロード (1204K) -
張 東豪, 宮坂 啓象, 石川 欣造1974 年 30 巻 5-6 号 p. T199-T202
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーThe crystallinity and the disorder of crystallites were measured by X-ray diffraction method for ramie fibers treated with various concentrations of caustic soda with and without constraints.
The crystallinity monotonously decreases with increasing concentration of caustic soda in the samples treated under constraint, whereas it decreases and again increases with the increases of concentration in the samples treated without constraint.
In the case of sample treated under constraint, the order of crystallites increases remarkably with the concentration of caustic soda, while it remains unchanged for the samples treated without constraint.抄録全体を表示PDF形式でダウンロード (268K) -
甲斐 昭, 戒能 俊邦, 小林 靖二1974 年 30 巻 5-6 号 p. T203-T207
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーThe fine structure of microfibril of Valonia macrophysa was examined from the experimental results; weight loss, leveling off _??_ and the observation of the residue by electron microscope after treatment with hydrochloric acid at boiling point.
The following results were obtained;
1) Amount of crystalline region was 80%.
2) Leveling off _??_ of Valonia was found to be about 2000. The value was 10-20 times larger than that of other native cellulose.
3) The crystallites with the length of the leveling off _??_ (about _??_ μ) were not observed by electron microscope.
The facts described above suggest that the Valonia microfibril is composed of extended chain and less disordered region in longitudinal section.抄録全体を表示PDF形式でダウンロード (1265K) -
山崎 晃, 臼田 誠人, 中野 準三1974 年 30 巻 5-6 号 p. T208-T213
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーFine structure of tobacco cellulose was studied with respect to the change of highly ordered region of cellulose by the alkali treatments.
Holocelluloses were prepared from leaf midribs and stalk shreds of native and flue cured tobaccos by the peracetic acid method. The leaf midrib holocellulose has a larger quantity of mannose and smaller quantity of xylose than the stalk holocellulose. It should be emphasized that the hemicellulose of leaf midribs is softwoodlike, while the hemicellulose of stalk is harwood-like. There is no characteristic difference in sugar composition between native and flue cured tobaccos.
A conclusion that the highly ordered region of stalk cellulose is larger in size and higher in degree of order than that of the leaf midrib cellulose can be drawn from the lateral order distribution of cellulose and acid hydrolysis rate constants, water adsorption and average degree of polymerization of hydrolyzed residue of alkli treated holocellulose.
The amounts of crystalline region and the levelling-off DP of flue cured tobacco cellulose: are larger than those of native tobacco. However, there is no remarkable difference in the fine structures of cellulose between native and flue cured tobaccos.
Comparing with wood cellulose, tobacco cellulose has a larger solubility in alkali fractional dissolution. The levelling-off DP of alkali treated tobacco cellulose is about one half of that of wood cellulose. The water adsorption of the highly ordered region of the alkali treated tobacco cellulose is higher than that of wood cellulose by 1%.
These results show that the highly ordered region of tobacco cellulose is smaller in size and lower in degree of order than that of wood cellulose.抄録全体を表示PDF形式でダウンロード (376K) -
Hyoe Hatakeyama, Tatsuko Hatakeyama1974 年 30 巻 5-6 号 p. T214-T220
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーThe change in the structure of amorphous cellulose containing drawn amorphous cellulose, by heat-treatment, has been investigated with the use of differential scanning calorimetry (DSC) and infrared spectrometry.
The exothermic peak observed from 100 to 180°C in DSC curves of undrawn and drawn amorphous cellulose was assumed to come from the formation of hydrogen bonding by free OH groups formed during the preparation of amorphous cellulose from cellulose triacetate. It was also inferred that some of the orientation of the cellulose molecules observed in drawn cellulose triacetate was retained in drawn amorphous cellulose even after the saponification, since the apparent heat of formation (ΔH) values of drawn amorphous cellulose samples were lower than those of undrawn amorphous cellulose.
It appeared that the exothermic peaks observed in DSC curves correlated well with the band at 1590cm-1 in infrared spectrometry. This band, which appeared with the heat-treatment of amorphous cellulose was supposed to be due to OH groups, which tend to form hydrogen bonds in amorphous cellulose. X-ray diffractograms of undrawn and drawn amorphous cellulose, heat-treated under dry nitrogen atmosphere, did not show crystal formation despite the formation of hydrogen bonding.抄録全体を表示PDF形式でダウンロード (465K) -
木村 実, 臼田 誠人, 門屋 卓1974 年 30 巻 5-6 号 p. T221-T227
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーThe mechanical properties of pulp sheet, cellulose and hemicellulose were studied by means of the torsion pendulum over a temperature range from -120°C to 190°C. The samples were kept under a vacuum of 10-2mm Hg for more than 48 hours at 20°C, and then for 2 hours at 120°C prior to the measurements. Heating rate was about 1.5°C/min. for all samples.
Below room temperature, three mechanical damping peaks were observed for linter cellulose at-100°C, -40°C and -25°C. When the damping vs. temperature curve of linter cellulose is compared with that of triphenylmethyl cellulose, the peak at -100°C is attributed to the motion of C-6 methylol group in the glucose residue. A drastic decrease in the relative rigidity and a large damping peak in pine glucomannan and birch xylan were observed at room temperature, and they are attributed to the motion of side chains of hemicellulose. The shear modulus and damping behavior of pulp sheet are similar to those of linter cellulose over a temperature range from -120°C to room temperature. However, the damping peaks of pulp sheet shift to lower temperature. These results suggest that hemicellulose within pulp sheets has no significant contributions to the molecular motion of cellulose, and that the shift of the damping peaks to the lower temperature region is attributed to the lower degree of orientation of cellulose.抄録全体を表示PDF形式でダウンロード (472K) -
小足 克衛, 森 秀夫, 京極 与寿郎1974 年 30 巻 5-6 号 p. T228-T233
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーThe properties and structure of natural cellulosic fibers were investigated by sonic velocify, visible dichroism and x-ray diffraction methods. The following results were obtained: (1) There is a good agreement between the orientation factor determined from the x-ray diffraction method and the visible dichroism of dyestuffs. (2) A linear relation exists between the sonic velocity (C) and the orientation factor from x-ray diffraction (fx); C=8.54fx-0.72(km/sec)for0.6<fx<0.9 (3) A relation between the sonic velocity or modulus and the moisture regain is in two states. This behavior corresponds to the absorption mechanism and is comparable with those of regenerated cellulose and acetate fibers.
A fibrillar structure gives a good explanation of the behavior of natural cellulosic fibers. The dichroic dyestuffs are believed to absorb onto the surface of the fibrils and orient along with them. The frber modulus E of the assembly of the fibril is given by Hearle1); Where Ef is the fibril modulus taken along the fibrii length, Kfthe bulk modulus for the assembly, θ the angle between the fiber axis and the fibril, σ the fiber Poisson's ratio. When σ is 1/2 or θ is small, the fiber modulus is given by the fibril extension mechanism alone; When this equation is combined with the Hermans'orientation factor, the fiber modulus is: Where C and Cf are the sonic velocity along the fiber axis, and the fibril, respectively. This equation gives a good explanation of the experimental relation between the sonic velocity and the orientation factor determined from x-ray diffraction, and the fibrillar orientation can be derived from the sonic velocity measurements. The value of the fibril modulus Ef calculated is 11.3×1011 dyne/cm2. This value is close to 12.7×1011dyne/cm2 which is the value of the modulus for the cellulose crystal lattice calculated from an x-ray technique2).抄録全体を表示PDF形式でダウンロード (400K) -
山崎 茂幸, 中尾 統一1974 年 30 巻 5-6 号 p. T234-T244
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーThe dissolution of cellulose in 100 organic solvents in the presence of small amounts of amines and SO2 has been investigated.
It is found that natural cellulose is dissolved in 34 solvents, while regenerated one is not dissolved under the conditions investigated. Microscopic observation of the dissolution process shows that the cellulose fibers are at first cleaved and then dissolved into the solution from the fracture surfaces without appreciable swelling.
The specific conductivities of the tertiary and the related solutions, the solubility of cellulose in the solution which contains amine excess to SO_??_, and the IR spectra of the cellulose solutions are measured. Considerations on the properties of effective organic solvents and amines, together with the discussions on the results of above measurements, give the conclusions: 1) organic solvents which act as electron acceptor are effective for the dissolution, and 2) cellulose is dissolved by forming the tertiary complex, a small fraction of which dissociates to Cell-O-SO_??_2N_??_R3H.抄録全体を表示PDF形式でダウンロード (788K) -
大河原 信1974 年 30 巻 5-6 号 p. P245-P253
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーPDF形式でダウンロード (553K) -
荻原 允隆, 久保田 仁1974 年 30 巻 5-6 号 p. T245-T249
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーThe complex formations between carbohydrates and ferric ion(Fe3+) were confirmed by UV-visible absorbing spectrum, indicating the peculiarity of Fe3+ among the other metallic ions. A large contribution of carboxylic groups in addition to hydroxyl groups was also found in the formation of the complex. It is believed that the adsorbing reactions of Fe3+ on cellulosic materials take place essentially in the hydroxyl groups in glucose unit by examining some cellulose derivatives.
However, the affinities between the introduced groups and Fe3+, and the change in the structure of cellulose by modifications can be added to the causes of adsorption.
It is interesting to note that in the cellulose samples modified moderately with nitrate or acetyl group a markedly large Fe3+ adsorption takes place, despite of their poor affinities for Fe3+抄録全体を表示PDF形式でダウンロード (321K) -
片岡 和正, 青木 昭二, 古畑 研一, 酒井 哲也, 礪波 宏明1974 年 30 巻 5-6 号 p. T250-T254
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーReverse osmosis of aqueous sodium chloride and maltose solutions was studied for cellulose acetate asymmetric membranes.
Similar results were obtained concerning the effects of heat treatment of the membrane and permeation pressure on the reverse osmosis, which operated in the normally used or reverse directions. The value of apparent activation energies of permeation implies that the mechanism of permeation of maltose is different from that of sodium chloride. It was also suggested that the mechanism of permeation in the reverse direction may differ from that of permeation in the normally used direction.抄録全体を表示PDF形式でダウンロード (279K) -
京極 与寿郎1974 年 30 巻 5-6 号 p. P254-P259
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーPDF形式でダウンロード (1878K) -
稲垣 訓宏, 山中 正博, 勝浦 嘉久次1974 年 30 巻 5-6 号 p. T255-T259
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーThermal degradation of cellulose methyl phosphonate(I) and cellulose methyl phosphate(II) was studied by thermogravimetry(TG) and infrared spectroscopy.
TG curves showed that the threshold temperature of I was lower than that of II and the amount of the residue of I larger than that of II. The value of activation energy estimated by kinetic analysis explained these observations. Both I and II were degraded in two stages. The first was the formation of double bond in cellulose chains. The second was the formation of polyene structure in cellulose. Compared with the thermal degradation of cellulose phenyl phosphonate and cellulose phenyl phosphate reported previously, the introduction of methyl group into phosphorus ester group accelerated to the formation of double bond. The formation of double bond seemed to relate closely to the electron density in phosphoryl group. The cis-β-elimination mechanism of phosphorus ester group was proposed for the formation of double bond.抄録全体を表示PDF形式でダウンロード (295K) -
牧田 実1974 年 30 巻 5-6 号 p. P260-P267
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーPDF形式でダウンロード (2852K) -
加納 直, 石津 敦, 細谷 修二, 中野 準三1974 年 30 巻 5-6 号 p. T260-T265
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーThe behavior of glycosidic linkages to the oxygen-alkali treatment has been studied, using low molecular compounds. This treatment of cellobiitol yielded many kinds of acids (Fig.1) together with glucitol which was only one neutral product. These acids, except 3-deoxy-pentonic acid (VII) and 3, 4-dihydroxybutyric acid (VIII), were also formed from glucose by the same treatment. This result suggests that glucose may be a precursor of the acids other than the acids (VII) and (VIII), although it was not detected among the degradation products owing to its low stability under the severe alkaline conditions adopted. The formation of the acids (VII) and (VIII), and glucose from cellobiitol may be explained by the scheme shown in Fig.2. A scheme in which hydroxyl radical is involved in the cleavage of glycosidic linkages (Fig.3) was expected, but found not to be important, if any, because the yield of gluconic acid was lower than that of mannonic acid. The formation of glucitol from cellobiitol can be explained by the scheme in Fig.4, but the cyclic acid (XII) which should be formed according to this scheme could not be detected.
The oxygen-alkali treatment of methyl 4-O-methyl-β-_??_-glucopyranoside yielded only three kinds of acids. They were separated gas-liquid chromatographically as TMS derivatives (Fig.5) and identified as glyceric acid, methyl 2-carboxy-3-deoxy-β-D-pentofuranoside (XIV) and methyl 2-carboxy-3-O-methyl-β-D-pentofuranoside (XVII) by the use of a mass spectrometer (Fig.6).
Methyl β-D-glucopyranoside has the same stability to oxygen-alkali as methyl β-D-xylopyranoside, though the former contains an extra primary hydroxyl group (Table 1).抄録全体を表示PDF形式でダウンロード (374K) -
高橋 史朗, 愛甲 裕1974 年 30 巻 5-6 号 p. T266-T272
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーPurified cotton linter was oxidized with NaIO4 to dialdehyde cellulose, and oximated with NH2 OH•HCl. The dioxime cellulose obtained was reduced to amino cellulose with NaBH4 in alkaline solutions. In the preparation of amino cellulose, the optimum conditions of the oximation and the amination were studied.
The rate constant of oximation, which was calculated from the N% of dioxime cellulose obtained, was 4.18 × 10-4 l/mol•min. at 20°C, and the activation energy was 1.98 kcal/mol. By treating dialdehyde cellulose with a 0.4M NH2OH•HCI solution at pH 5.20 for 90min. at 25°C, about 97-100% of carbonyl groups was converted to oxime groups. The dioxime cellulose were unstable to alkaline solutions, and the content of oxime groups decreased by the treatment with NaOH solutions (pH>11).
The maximum degree of amination was attained by the treatment with a 10% NaBH4 solution at an initial pH of 9.5 for 24 hrs. at 25°C, and about 50% of oxime groups were aminated. When the concentration of NaBH4 was higher than 10%, the degree of amination decreased. The degree of amination decreased when the initial pH value was either below 8.5 or above 10.5. When the reaction time was longer than 24 hrs., the content of amino groups resulted was decreased by the attack of alkaline solutions.抄録全体を表示PDF形式でダウンロード (400K) -
藤本 礼造, 細野 正夫, 辻 和一郎, 和歌崎 信夫1974 年 30 巻 5-6 号 p. T273-T279
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーA new processing for the carboxymethylation of cotton fabrics was studied. In order to prevent the byreaction of chloroacetic acid to glycolic acid, the cotton fabrics were first immersed in a mixed aqueous solution of sodium chloroacetate and sodium hydroxide at low temperatures and then carboxymethylated by heating. Some properties of the fabrics carboxymethylated by this procedure under different conditions were examined. It was found by these examinations that the cotton fabrics were carboxymethylated more uniformly than by conventional methods.
This new method is considered to be useful for the continuous carboxymethylation of cotton fabrics.抄録全体を表示PDF形式でダウンロード (423K) -
藤本 礼造, 辻 和一郎1974 年 30 巻 5-6 号 p. T280-T285
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーPartial carboxylmethylation of cotton fabrics was examined using glycolic acids and sulfuric acid, phosphoric acid. or acetic acid as acidic catalyzers. It was found that the reaction of this procedure gave a partially carboxylmethylated cellulose having the crystalline lattice of cellulose I, whereas the usual method used to date where the reaction was achieved in the chloroacetic acid-sodium hydroxide system gave crystalline lattice of cellulose II.抄録全体を表示PDF形式でダウンロード (346K) -
坂本 宗仙, 崔 錫哲, 村上 二郎, 佐藤 敏雄, 手代木 琢磨1974 年 30 巻 5-6 号 p. T286-T291
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーA new crosslinking agent for cellulose, bis-γ-isocyanatopropyl disulfide (BIPD) was synthesized from γ, γ′-dithiodibutyric acid and its reaction with cotton cellulose in dimethylacetamide was investigated in comparison with the reaction of homologous bis-β-isocyanatoethyl disulfide (BIED). Diisocyanate-treated cotton was reduced with tri-n-butylphosphine and the crosslinking efficiency (crosslinks/total diisocyanate combined) was calculated from the nitrogen contents determined by the Kjeldahl method before and after reduction. BIPD reacted with cotton more slowly than BIED. The crosslinking efficiency of BIPD increased with reaction time and high efficiencies (>80%) were attained by prolonged treatment. No significant difference in the crosslinking efficiency was observed between BIPD and BIED.抄録全体を表示PDF形式でダウンロード (417K) -
池田 徹雄, 池田 洋子, 伊東 澄子, 辻 和一郎1974 年 30 巻 5-6 号 p. T292-T298
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーCrease recovery of cotton fabric grafted with acrylic acid and further treated with tris (_??_-aziridinyl) phosphine oxide (APO) was studied with a view of preventing the decrease of tensile strength accompanied with crosslinking.
Although the chemical structure of reaction products of APO with acrylic acid grafted cotton is more complicated owing to the presence of the carboxyl groups in the grafted polyacrylic acid than that of the reaction products of APO with ungrafted cotton, APO seems to react not only with hydroxyl groups in the cotton cellulose, as observed for the ungrafted cotton, but also with carboxyl groups in the grafted cotton fabric.
Crease recoveries of ungrafted and grafted cotton fabrics in both conditioned and wet states are much improved by treating with APO solution containing 2.5% zinc fluoroborate catalyst. Considerable crease-proofing effect is also observed when the grafted cotton fabrics are treated with APO solution without zinc fluoroborate catalyst, and the decrease in the warp tensile strength is prevented by this treatment. This method is particularly favorable to obtain a good crease recovery-strength relationship.抄録全体を表示PDF形式でダウンロード (459K) -
島田 真知子, 中村 好雄, 日馬 康雄, 松田 修, 田村 直幸, 景山 英一1974 年 30 巻 5-6 号 p. T299-T304
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーThe types of free radicals formed by γ-irradiation in cellulose I and II were studied. The ESR spectra obtained with the γ-irradiated cellulose I and II were changed by contacting the fibers with water, and also the spectra for these fibers after immersion in water were varied by orientations of fiber axes to the magnetic field. These spectra seem to be related to the free radicals generated in the highly ordered regions inaccessible to water in irradiated cellulosic fibers. And the spectral differences between cellulose I and II may be due to the differences in the molecular conformation in the crystal lattices. As a model of typical amorphous regions in cellulose, decrystallized cellulose was prepared. The ESR spectrum of irradiated decrystallized cellulose was simple. When the sample was contacted with moisture, the ESR spectrum changed to a narrow singlet, which gradually decreased the intensity until the spectrum completely disappeared. By subtracting the spectrum of free radicals remaining in decrystallized cellulose after contacting with moisture from the spectrum of decrystal-lized cellulose, it was found that the types of free radicals formed in the decrystallized cellulose consisted of the overlap of narrow singlet (line width 8G, g-value 2.0050) and doublet (splitting 10G, g-value 2.0045) spectra. The singlet spectrum is attributed to alkoxyl radical formed by the rupture of glycosidic linkage at C1 or C4 position, and the doublet spectrum is ascribed to the radical formed by hydrogen abstraction from C1 position. When the ESR spectra of free radicals formed in the highly ordered regions of the irradiated cellulose I and II were added to the spectra of the singlet and doublet in adequate ratio, the constructed spectra were similar to the spectra of free radicals scavenged by water in cellulose I and II. From these facts the spectra generated by free radicals in the amorphous regions accessible to water in the irradiated cellulose I and II are considered to be composed of the ringlet and doublet formed by free radicals in the typical amorphous regions, and the spectra of other types of radicals, which are similar to the spectra for free radicals formed in crystal regions inaccessible to water. It is considered that the radicals are generated mainly in the typical amorphous regions in cellulose, since the contribution of the doublet spectrum is great in these constructed spectra for both cellulose I and II.抄録全体を表示PDF形式でダウンロード (394K) -
木戸 猪一郎, 池田 功夫, 鈴木 公宏, 山下 研治, 岩田 健, 伊藤 義信1974 年 30 巻 5-6 号 p. T305-T312
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーRayon filament yarn was metallated with Li, Na and K methoxide solutions in methanol, and then graftcopolymerized with acrylonitrile (AN) and other monomers such as methyl acrylate (MA) and methyl methacrylate (MMA) solutions in dimethyl sulphoxide (DMSO).
The degree of Na-metallation vs. Na methoxide concentration curve had a maximum for the non-swollen rayon, while the degree of alkali-metallation of the swollen rayon was directly proportional to the alkali methoxide concentration irrespective of alkali ions (Li, Na or K) except for the region of lower methoxide concentration.
The degree of metallation for the swollen rayon were in the order of Li>Na>K in the region of the higher methoxide concentration, while the order of Li<Na<K was observed in the region of the lower methoxide concentration. It was assumed that the methoxide concentrations inside of the swollen fiber would be so much increased by the sorption of methoxides and the effect was more remarkable in the order of Li<Na<K, i. e. with increasing ionic radii, that the degrees of metallation were proportionally increased in the region of the lower methoxide concentration. The activation energy of Na-metallation was obtained to be 2.4 Kcal/mol for the swollen rayon.
The graft-on vs. AN concentration curve for the Na-metallated rayon had a maximum at AN 40-60 vol% in AN-DMSO medium. The graft-on vs. degree of metallation curves for Li, Na and K had maxima, respectively, and the graft-ons approached zero in the regions of higher degree of metallation. Therefore it could be presumed that the alkoxide groups were combined so strongly by polar bondings with each other that the rayon turned homy and inactive to the anionic polymerization at higher methoxide concentrations.
The number average molecular weights (_??_) of the graft polymers were 1, 000-16, 000 and gave a maximum against the AN concentration in the AN-DMSO medium. The initiation efficiency of the combined Na, which was obtained from ratio of the calculated _??_ to the found _??_., also gave a maximum with increasing AN concentration.
In the case of methyl acrylate as monomer, the graft-on vs. degree of metallation curves had maxima whose positions nearly coincided with the maxima of the AN grafting. These facts also would prove the assumption that the rayon turned horny and inactive at the higher methoxide concentrations.抄録全体を表示PDF形式でダウンロード (544K) -
上床 恒弘1974 年 30 巻 5-6 号 p. T313-T314
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーThe cationic pulp has characteristic properties due to a positive zeta potential, which are essentially different from those of the negatively charged conventional pulp.
A method was studied to prepare the cationic pulp inexpensively without damaging of cellulose. Commercial softwood bleached kraft pulp (N-BKP) was treated with cyanamide compound. The following conditions are recommended; concentration of sodium acid cyanamide: 50-200g/l,
PH: 10-13, reaction temperature: 10-40°C, reaction time: 4-24 hrs. The maximum degree of substitution (DS) of nitrogen of cationic pulp was less than 0.05 for the original N-BKP and slightly higher than 0.05 for the alkali pre-treated pulp. This implies that the alkali pre-treatment of cellulose increases the DS.抄録全体を表示PDF形式でダウンロード (129K) -
松沢 秀二, 小笠原 健二, 松村 峰彰1974 年 30 巻 5-6 号 p. T315-T316
発行日: 1974/05/10
公開日: 2008/11/28
ジャーナル フリーA polyvinyl alcohol having aldehyde groups at the ends of molecule (APVA) (DP=320) was prepared by the oxidative cleavage with periodic acid of polyvinyl alcohol derived from polyvinyl acetate polymerized at 60°C in bulk. Rayon staples were immersed in a acidic aqueous solution of the APVA and allowed to react with it. The rate of crosslinking was estimated by the insoluble fraction in copper ethylene diamine hydroxide.
The fraction of the rayon staples treated with APVA was smaller than that treated with formaldehyde.抄録全体を表示PDF形式でダウンロード (118K)
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