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Carbon fibre (CF) is widely used in CF reinforced plastic (CFRP) components. However, waste CF, CFRP and the end-of-life (EOL) CFRP structures will cause an even bigger problem in the next years because of strict environmental regulations. Currently, recycling is carried out almost entirely by the use of pyrolysis to regain CF as a valuable resource. This high temperature process is very energy consuming and the resulting fibres are brittle. Hence, not suitable for textile processing into yarns or fabrics. To enable a grave to cradle circle, a new approach based on a solvolytic recovery of CF and the subsequent spinning process to obtain a hybrid yarn suitable for weft knitting processing is the focus of the international research project IGF/CORNET 256EBR “3D-r-CFRP”.

The local structure of cellulose, dissolved in the frequently used ionic liquid EMIm-OAc, is modelled by a coaxial double layer cylinder. The cylinder’s core consists of a cellulose chain while the sheath is formed by a solvent layer with lower electron density than the bulk solvent. We studied 2% cellulose solutions in EMIm-OAc and their behavior upon addition of increasing amounts of water. At this cellulose concentration, 15 wt% of water induced the precipitation of cellulose. Water molecules did not form an independent phase, but were bound to EMIm-OAc in the cellulose/water/EMIm-OAc solution. The conformational of a cellulose chain changes by adding water into the solution, and the square of the apparent cross-sectional radius of gyration of the cellulose chain becomes zero to negative. This phenomenon is explained by the formation of a solvation shell with lower electron density than the bulk solvent around the cellulose chain.

Although cellulose is the oldest macromolecule we have known, its intrinsic properties are still not well understood because of the lack of suitable solvents. The recent development of ionic liquids enables preparation of cellulose solutions in which cellulose molecules are supposed to be dispersed molecularly. Conventionally a semi-flexible-chain model or a worm-like chain model has been applied to describe the dilute solution properties of cellulose. A semi-flexible chain model is specified in terms of a persistent length to determine the chain stiffness of a solute molecule, completely neglecting details of the solvent–solute interaction, and the discussion is mainly focusing on the conformation of a solute molecule. In this paper we adapt a cylinder model which at least specifies the local shape of a solute molecule. Since the ionic liquids are now available as a new solvent of cellulose, we have prepared cellulose/ionic liquid solutions for small-angle X-ray scattering (SAXS) measurements which provide information on the local structure of cellulose molecules in the restricted range. The SAXS measurements were performed on the cellulose/ionic liquid solutions at two independent synchrotron facilities and confirmed the consistency of the observed scattering profile. Standard methods were applied to analyze the scattered data first, and afforded a model for representing a cellulose molecule in ionic liquid solutions. Two types of ionic liquids were used, and it was ascertained that cellulose was not degraded under the conditions used. The solution characteristic was found to change by heating during the preparation of each solution. The heating effect on the conformational change of cellulose was discussed in terms of the solute–solvent interaction from the simulation with a coaxial double layer cylinder model. The state of solvent packing was considered as well from the thickness and relative electron density of the sheath in the simulated coaxial double layer cylinder model.

The perception on clothing of elderly female were compared with that of youth, especially focusing on the sense of cool. The information were collected through the questionnaires given to the groups of elderly females in their 60, 70, and 80s and also to the female in their 20s for a comparison. In terms of the color taste, opinions and feelings about clothes, the sense of “cool” seems to be received in a different way between the youth and the elderly. However, when their lifestyle (behavior and information sources) were concerned, the perception of the 60s was closer to 20s. The 70 and 80s were divided by two groups. It could be by the sensitivity to information.

The emergence of Japanese street fashion in the 1990s in young girls has created a notion of generation identity and new fashion styles. Although Japanese street fashion was studied by scholars from multiple-disciplines, little research has been carried-out on its evolution overtime. This paper aims to examine its transition over a five year period from 2006 to 2011, and to explain the factors that led to these changes. In order to follow the transition of street fashion, survey questionnaires were distributed to a total of 1,094 female college students in Tokyo between 2006 and 2011. Further, fashion magazines were studied and surveyed to understand their evolution and the influence on their readers. The findings showed that economic recession in 2007, the fast fashion business, and the fashion models played a significant role in shifting the popularity of each style, and Casual style became the most popular style throughout the years of the study. In addition, fashion styles have merged and became difficult to differentiate by their appearances. Many fashion magazines also added Casual style to their publication. Finally, this paper suggests that teens created their own styles by combining several fashion elements, and as a result new styles such as Ageha and Mori girl were observed in the fashion scenario.

The purpose of this study is to elucidate a role of the street fashion as a habitual communication tool for the youth through the comparative study on the habitual behavior of the Japanese and Thai youths. The questionnaires concerning the fashion behavior were submitted to a total of 363 female college students in Japan and Thailand in 2011. The results revealed the significant differences in fashion behavior between the two countries, which were affected by the climate, personal income, and traditional lifestyle. The Japanese youths care much about their personal surroundings and adapt fashion as a communication tool for social networking to be accepted in a group. The Thai youths care less about fashion and seek for other tools for social networking. By the time of the survey, the Japanese street fashion has been already matured as a communication tool with a variety of expression ways and is transfiguring spontaneously by repeated diversification and integration of several fashion elements. On the other hand, Thai street fashion is in the early stage and has not yet fully developed to affect a way of personal communication. However, the Thai youths have been increasing interest in fashion as confirmed by the increasing popularity of domestic fashion magazines, and provide a potential for Thai street fashion to develop.

This article compares color assessments of automotive exteriors at four locations in China, Thailand and Japan. This study employed painted panels of twelve colors, thirty sensory words and fifteen pairs of emotion variables. It also used reference figures of nine cars that included four styling categories, namely sedans, compacts, sport utility vehicles and sports cars. The results of like–dislike tests revealed that basic automotive exterior colors, such as black, white and red, were highly preferred across locations. However, geographical differences are apparent in the preference for some non-basic colors. To elucidate these geographical differences, a Chi-square test and principal component analysis were performed on the data on emotion variables. The results revealed both similarities and differences in color preferences among the four locations. Color preferences were similar in Hong Kong and Shanghai when simply evaluated by color samples. However, similar preferences for automotive exterior colors were observed in Hong Kong, Kyoto and Bangkok, but not in Shanghai. These results suggest that there is fluctuation in the emotion evoked by a color when the color is considered in the context of automotive exteriors. Therefore, this study indicates that automotive sales can be secured in the global marketplace by creating a single palette of exterior colors based on similar color preferences across countries. However, these results also indicate that preparing market-specific automotive-color line-ups can be an effective marketing strategy.

Consumers' tolerance of the color of recycled paper was evaluated by the visual assessment of such pa- per by 30 Japanese university students. The assessment was performed to measure color tolerance using 266 color samples in eight conditions specifying the situation of paper as (1) ''either paper is recycled or not recycled,'' (2) ''whether you will buy/use,'' and (3) ''use for office paper or for workbook paper.'' The responses of the subjects were sorted out quantitatively in terms of the colorimetric values of color samples and then correlated with International Organization for Standardization (ISO) brightness and CIE whiteness. Both the ISO brightness and CIE whiteness were found to be dependent on hue factors and also to be restricted for use in direct repre- sentation of the consumers' responses to paper quality. Since the consumers' evaluation of paper quality is due to visual whiteness, we propose a new equation to predict the consumers' tolerance of paper color, in which the equation contains two factors concerning the color dis- tance from the white point and the hue impact. The new tolerance equation was confirmed to predict the consum- ers' tolerance successfully, particularly when the consum- ers are aware that the paper is recycled. 2011 Wiley Peri- odicals, Inc. Col Res Appl, 00, 000 - 000, 2011; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/col.20676

This is a preprint of an article published in Journal of Polymer Science: Part B: Polymer Physics. 46(19): 2126-2142 (2008)., The initial stage of fiber structure development in the continuous neckdrawing of amorphous poly(ethylene terephthalate) fibers was analyzed by in situ wide-angle X-ray diffraction, small-angle X-ray scattering, and fiber temperature measurements. The time error of the measurements (\600 ls) was obtained by synchrotron X-ray source and laser irradiation heating. A highly ordered fibrillar-shaped two-dimensional (smectic-like) structure was found to be formed less than 1 ms after necking. By analyzing its (0010) and (0020) diffractions, the length of the structure 60–70 nm were obtained. A three-dimensionally ordered triclinic crystal began to form with the vanishing of the structure around 1 ms after necking. The amount and size of the crystal were almost saturated within several milliseconds of necking, during which time a mainly exothermic heat of crystallization was also observed., Article, Journal of Polymer Science: Part B: Polymer Physics. 46(19): 2126-2142 (2008)

The effect of surfactants on the colour of hair dyed by an oxidation dye was studied paying attention to the difference in charge of the hydrophilic part of the surfactants. The surfactants employed in the experiments were anionic, nonionic and cationic ones. It was found that in the presence of cationic surfactants, the resulting colour of hair dyed by the p-aminophenol (PAP) and 5-amino-o-cresol (5AOC) system is more vivid than that of hair dyed without surfactants or with anionic or nonionic ones. The changing behaviour of hue, lightness and chroma with time for hair dyed by the PAP-5AOC system with cationic surfactants is different from that of other systems, which contain anionic or nonionic surfactants, or contain no surfactants. Especially the hair chroma (C*) for the cationic-surfactant-containing system increases monotonously with time, while C* for other systems increases at first and then decreases with time. The C* - L* (lightness index) relation curve for the cationic system shows a same tendency even at longer dyeing time (140 min). The C* of hair dyed by PAP-5AOC system for 40 min has maximum value at 0.03 M of cationic surfactant added, of which hydrophobic chain is hexadecyl.

General principles of electromagnetic wave scattering are sum-marized, with emphasis laid on small-angle X-ray scattering. Theconventional analysis of scattering data is based on the various waysof plotting the data according to the simple model approximation. Inorder to avoid the artifact due to the simple model approximation,the analysis of the scattering data is performed by either adaptinga triaxial model of homogeneous density distribution, a molecularmodel, or a density distribution function.

The performance of a ventilated mattress (VM) used as a bed-integrated local exhaust ventilation system combined with air cleaning fabric (acid-treated activated carbon fibre (ACF) fabric) was developed and studied. The separate and combined effect of the VM and the local air cleaning for reducing the exposure to body generated bio-effluents in a hospital room was determined. Full-scale experiments were conducted in a climate chamber furnished as a single-bed patient room. Two heated dummies were used to simulate a patient and a doctor in the room. The patient was lying on a bed equipped with the VM. The patient's body was covered with either a cotton sheet or with the ACF material used as a blanket. Ammonia gas released from the patient's groins simulated the body generated bio-effluents. At the location of the groins the surface area of the VM was perforated through which the contaminated air of the bed micro-environment was exhausted. Two modes of operation were studied: 1) the exhausted polluted air was discharged out of the room and 2) the polluted air was cleaned by the ACF material installed inside the mattress and recirculated back into the room. Both modes of operation efficiently reduced the generated bio-effluents in the room with about 70%. Reduction in the exposure to body-emitted ammonia was up to 96% when the VM was operated at only 1.5 L/s and the ACF was used as a blanket.

This study investigates the relationship between color perceptual attributes and color emotions, as well as the influence of different cultural backgrounds. Totally 214 color samples were evaluated on 12 emotion variables by subjects from seven different region groups in the psychophysical experiment. By factor analysis, it was found that three factors were sufficient to represent 80 11 "region-emotion" variables. For each variable, there is no distinct difference among different region groups. The 12 emotion variables could be divided into four categories, namely, activity index, potency index, definition index, and temperature index. Factor scores were further calculated to study the determinants on each factor. The analysis showed that the three factors were mainly related to chroma, lightness, and hue, respectively. It was concluded that chroma and lightness were the most important factors on color emotion, whereas the influences of hue and cultural background were very limited. (c) 2007 Wiley Periodicals, Inc.

The chemical crosslinking of funoran, a sulfated galactan, was attempted by using polyethylene glycol diglycidyl ethers in order to prepare a gel for using as a water-absorbing network polymer contained in disposable napkins. The funoran gel was not obtained under a series of crosslinking conditions. Other sulfated polysaccharides, such as Kappa-and Lambda-carrageenan, were not also crosslinked by the diglycidyl ethers, while agarose was chemically crosslinked to give its gel. Agarose has the same chemical main chain as funoran but has no sulfuric acid groups. The bulky sulfuric acid groups may intercept sterically the reaction between the hydroxyl groups and the glycidyl groups of the crosslinker.

In order to clarify the mechanism of interaction between FGF-2 and heparin, the association structures between human FGF-2 and different kinds of regioselectively desulfated heparins were observed by small angle X-ray scattering. In the FGF-2-native heparin complex, the global FGF-2 molecules appeared to attach along heparin chain as strained unilaterally. The complexes with the 6-O-, or N-desulfated heparin seemed to have randomly associated structure as compared with above system. On the other hand, 2-O-desulfated heparin did not indicate the aggregation with FGF-2, indicating that the sulfate groups at O-2 of iduronate residues in heparin is most essential for association with FGF-2. These structural characteristics will be deeply related with signal transduction in the association with FGF-2 receptor.

This is a preprint of an article published in JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS. Vol 43(9): 1090-1099 (2005)., Article, JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS. 43(9): 1090-1099 (2005)

Effect of counter-anion on the properties and morphology of aliphatic poly(oxytetramethylene) ionenes was investigated, and the relationship between the properties and morphology was elucidated. The ionenes possess elastic properties at low elongations whereas they predominantly exhibit a plastic deformation at high elongations. The morphology of the ionenes was analysed in the nanometer scale by fitting a cascade model for randomly branched f -functional polycondensates incorporated in Debye–Bueche random-two-phase model and the interference term by the interdomain interaction on their small-angle X-ray scattering profiles. The size of ionic domains and distance between the domains were smaller and shorter in the ionene with bromide counter-anion than those in the ionene with chloride counter-anion, respectively. The formation of crystallite of poly(oxytetramethylene) (POTM) segments was detected in the ionene with chloride counter-anion at room temperature. These characteristics of aliphatic POTM ionenes gave the difference in their mechanical and thermal properties.

We have studied the strip biaxial tensile behavior of natural rubber vulcanizates filled with silica by the conventional milling method and by the in-situ silica filling method. The rapid increase of both stresses along the stretching and the fixed axes after the initial stretching was observed on samples filled with a conventional silica by the milling method. Low strain dependence of stresses in the successive strain regions was followed by the rapid increase of the stresses at the higher deformation region. On the other hand, we did not observe such behavior for the samples filled with silica generated in-situ in the rubber matrix before curing. The transmission electron microscopic measurements showed that a highly developed aggregated structure of silica particles was suggested in the conventional silica filled samples and just a simple aggregation was suggested in the case of the in-situ silica filled samples. The differences between samples reinforced with two different filling methods in low tensile region are mainly attributed to the aggregate structure of the silica particles dispersed in the rubbery matrix. We estimated the functional form of the strain energy density function for the samples filled with silica in intermediate and large deformation regions: =C10(I1−3)+C01(I2−3)+C20(I1−3)2 The estimated W was found to reproduce the experimental stress-strain curves in intermediate and large deformation region. The relative contributions of three terms in the estimated W for the samples prepared by the in-situ method show the different dependence on the silica content from those of the samples containing silica mixed by the conventional method.

Static and dynamic structures of water molecules have been inspected in aqueous solutions of di-and penta-α- and -β- d -glucopyranose (maltose, cellobiose, maltopentaose, and cellopentaose) outside the first hydration shell around the saccharides, using a molecular dynamics simulation which includes all degrees of freedom concerning atomic motion. The aim is to inspect the solute effect on water molecules in the aqueous solution systems corresponding to the length or the kind of the glycosidic linkage. We use the partial radial distribution function and two kinds of angular distribution functions for the static analysis, and find peculiarities in the solutions of both α-linked saccharides, maltose and maltopentaose. The broadness of the hydrogen bond network distribution in the maltose solution is particularly related to the translational motion of water molecules which is slowest in the maltose solution. The rotational motion of water molecules is significantly slow in the cellopentaose solution. The solute effect can be detected outside the first hydration shell around the solute, and is most noticeable in the translational motion.

The gelation mechanism of κ- and ι-carrageenan with various types of monovalent counter ions are considered by means of small-angle X-ray scattering. The extent of chain aggregation was discussed with the cross-sectional radius of gyration estimated from cross-sectional Gunier plots. The gelation of κ-carrageenan found to involve the multiple aggregation of double helices except for Li+ and Na+-type, while ι-carrageenan gel was consisted of just double helices.

A molecular dynamics simulation, which includes all degrees of freedom of atomic motion, has been carried out for aqueous maltose and cellobiose solutions in order to investigate whether the solvent as a background of solutes changes its dynamic characteristics or not. Mean square displacement, velocity autocorrelation function, rotational correlation function, and newly defined hydrogen bond correlation function have been calculated for the whole solvent from which the first hydration shell of the solute was omitted. The first three functions concern motions of each water molecule, and the last one reveals relative motions of water molecules. Translational and rotational motions of water molecules are restricted more in the solution than in the bulk water, because the network defects, which weaken the power of a water molecule to retain others, exist less in the solution than in the bulk water. Between two solution systems, this tendency is stronger in the maltose solution than in the cellobiose one. The difference between two solution systems is clearly demonstrated in the present study dealing with the dynamic structure, although it was not clear in the static structure revealed in our previous paper.

The characteristics of the running of color (“nijimi”) were quantitatively analyzed in order to elucidate the difference of natural indigo dyeing and conventional synthetic indigo dyeing. The luminance distribution curves and half-widths of the running of color were evaluated for the clothes tie-dyed with traditional natural indigo and conventional synthetic indigo. A single Gaussian function fits to the profile of the running of color produced by natural indigo reduced by fermentation, while the running of color produced by synthetic indigo prepared with sodium hydrosulfite was approximately represented by a linear sum of two Gaussian functions. The half-width profile of the running of color is in the following order : synthetic indigo ⁄ reduction method (sodium hydrosulfite) > synthetic indigo ⁄ reduction method (zinc powder) > natural indigo ⁄ reduction method (fermentation). The running of color is thus concluded to be due to the mode of indigo penetration into fiber, which depends on dyebath preparation. A critical difference in dyeing process is the speed of reduction of indigo, and could not be attributed to a small amount of impurity contained in natural indigo.

The effects of washing on color were quantitatively examined using a colorimeter to elucidate subtle color difference between cotton cloth samples dyed with natural indigo and synthetic indigo. Color produced by reactive dye and indigo was also compared and the results were analyzed by a CIELAB color system. Color unevenness was subjectively evaluated by seven professional indigo dyers. With repeated washing, L* value in cloth dyed with natural indigo increased at a lower rate than in cloth dyed with synthetic indigo. Color unevenness is related to dye absorption and dye aggregation.

The structure, mechanical properties, and thermomechanical properties of poly(ethylene terephthalate) (PET) fibers obtained by laser-heated drawing were investigated in terms of their dependence on the draw ratio and feed speed and the differences between neck-drawn fibers and flow-drawn fibers. The long period at a draw ratio of 6.0 reached 19.0 nm, notably larger than at lower ratios, whereas the tilting angle of the laminar structure was constant at about 60°, regardless of the draw ratio. A maximum value of 15.0 GPa was attained for the initial modulus, and 1.07 GPa was attained for the tensile strength. A higher tensile strength orientation-induced crystallized fiber at the same initial modulus was obtained from higher molecular weight PET. The relationship between the compliance and molecular orientation of the amorphous phase was studied with a series model of crystalline and amorphous phases. The results revealed that, in the high-draw-ratio fibers, the compliance of the amorphous phase decreased with the draw ratio at a higher rate than indicated by extrapolation to intrinsic values. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 79–90, 2004

κ- and ι-carrageenan in aqueous solution undergoes reversible sol/gel transition by cooling or increasing concentration. The small-angle X-ray scattering profiles from carrageenans were observed at different temperatures and concentrations. The results were analyzed by means of molecular models of double helix or associated double helices. It was found that κ-carrageenan formed two or three associated double helices by gelation, although gelation took place in ι-carrageenan mostly by the transition from single chain to double helix without association. λ-carrageenan exhibited the normal scattering behavior of polyelectrolyte in solution.

Gellan gum in aqueous solution undergoes gelation by adding the metal salts. The cross-linking domain structure in various concentrations of potassium salt was observed by small angle X-ray scattering. The results were analyzed by means of molecular models of associated double helices. It found that the gelation yielded the mono-layer flat particles constructed by side-by-side aggregation of double helices at lower salt concentration and then they grew up to the multi-layer aggregates by a further addition of salt.

The effects of copper plate surface-treatment with 3-aminopropyltriethoxysilane (APS) on the adhesion between the copper plate and polyethylene plate through polyethylene gel have been investigated by tensile shear test, DSC measurement, and FT-IR measurement. The copper plate was treated with an ethanol–water mixed solvent containing water content of 30 vol% as a solvent of the APS, the polysiloxane structure favorable for the adhesion between polyethylene and copper plate is formed rapidly. The interfacial shear strength goes up to over 8 MPa when treated with the APS solution in concentration of about 5.0 × 10-2 moll-1. The flexible polysiloxane networks formed from the APS solution on copper plate were found to act effectively for the adhesion. Experiments for model substances corresponding to the interphase in the present adhesion on the basis of DSC measurement and FT-IR measurement have revealed that the flexible polysiloxane networks formed from the APS solution and polyethylene chains as an adhes...

The method for the formation of adhesive phase onto polyethylene (PE) fiber surface by passage of the PE fiber through hot PE solutions has been investigated for making composite materials reinforced by the PE fibers. When the PE fiber is treated by the low density PE (LDPE) solution in o-xylene in the range of 120 to 135°C, the tensile strength of the PE fiber is maintained at that of the original PE fiber. Adhesive strength between the PE fiber surface and LDPE phase formed on the PE fiber through the hot PE solution is found to be so high that the PE fiber itself is torn off. The application of the present method to PE fiber-reinforced PE composites will be expected.

Gellan gum undergoes gelation by forming domains composed of associated double helices. Here the further random aggregation of associated double helices seems necessary for the formation of the network in the case of Na-gellan with adding NaCl. Gellan gum aqueous solutions were prepared with or without adding various concentrations of NaCl, and their gel-sol transitions were observed by the differential scanning calorimetry (DSC) and the small-angle X-ray scattering (SAXS). The DSC endothermic peaks are attributed to the dissociation of the ordered domains, and the network dissociation in the case of gel samples. The SAXS results are analyzed in terms of the molecular models of associated double helices.

1 H NMR measurements on spin–lattice relaxation time ( T 1 ) and spin–spin relaxation time ( T 2 ) were carried out on water contained in water-swollen copolymer gels prepared from hydrophilic methacrylic acid and hydrophobic stearyl methacrylate (SMA) or lauryl methacrylate (LMA). The degree of swelling of the copolymer gels decreases drastically with increasing component of hydrophobic monomers. 1 H T 1 and T 2 of water show linear relationship with the cube root of the degree of swelling. Motion of water is restrained with the decreasing network size and the amount of hydrophobic groups in the network. T 1 measurements with temperature change revealed that the hydrogen bondings in water are decreased by introducing hydrophobic groups into the hydro gel..

膨潤時に応力を印加して伸長する, いわゆるプレ延伸を付加した膨潤-延伸法に重量平均分子量330万のポリエチレンを適用して, 超延伸が可能になる条件を探索した. その結果, シート成形時の融解温度に保持する時間 (融解時間) および冷却速度がプレ延伸性および延伸性に大きな影響を及ぼすことがわかった. 融解時間については8時間, 冷却側速度については4℃/minのとき延伸率は極大を示すことがわかった. この条件で成形したシートを104℃のトルエン-シクロヘキサン (体積比, 95: 5) の混合溶媒中で2.2×102kg/m2の応力を印加して26倍までプレ延伸した後115℃で延伸すると, 得られる最大強度および弾性率は, それぞれ5.3GPaおよび215GPaに達することを明らかにした.

Color reflectance from the cloth dyed with natural indigo was quantitatively compared with that from the cloth dyed with synthetic indigo by the spectrophotometric method, and the results were analyzed by a CIELAB color system. The cause of the color difference between the clothes dyed with natural and synthetic indigo was attributed to the mode of dye dispersion in fiber resulted from the aggregation of dye molecules during the reduction process. The results are summarized as follows: 1) The color produced by natural indigo is bluer and brighter than color produced by synthetic indigo reduced by sodium hydrosulfite. 2) The color produced by synthetic indigo using zinc powder is more similar to the color of natural indigo than the color of synthetic indigo prepared with sodium hydrosulfite. 3) The chroma and hue of the cloth dyed with natural indigo are higher than the respective values of the cloth dyed with synthetic indigo reduced by sodium hydrosulfite when the clothes are dyed repeatedly. 4) The diffusion coefficient of synthetic indigo reduced by sodium hydrosulfite is higher than that of natural indigo, where the diffusion coefficient of synthetic indigo reduced by zinc powder is similar to that of natural indigo.

Poly(ethylene terephthalate) fibers were continuously drawn to high draw ratios under heating by CO2 laser irradiation. The structure of the drawn fiber was analyzed based on measurements of refractive index, wide-angle x-ray diffraction, and small-angle x-ray scattering. The average refractive index, birefringence, crystallite size, crystal orientation and the long period of the fiber structure were found to increase with the draw ratio. However, for fibers drawn to a final ratio of 6:1, neither the diameter of the laser beam, the feed speed, nor the laser power affected the fiber structure appreciably. The crystallite size and long period of a fiber drawn to a ratio of 4:1 were both altered more after annealing at fixed fiber length than for the 6:1 fiber. The lamellae structure inclination angle of samples drawn to both 6:1 and 4:1 was about 60°, decreasing after annealing to 50° for the 6:1-drawn samples and 30° for the 4:1-drawn samples.

The carrageenans are a family of sulfated polysaccharides extracted from red seaweed, and are conventionally classified into three major groups as κ-, ι- and λ-carrageenan according to the maximum number (1, 2 and 3, respectively) of sulfate groups per disaccharide repeating unit in corresponding ideal structures. β- and θ- carrageenan (not available in nature) possessing none and two sulfate groups per repeating unit, respectively, were prepared from κ- and λ-carrageenan by desulfonation. Here the aqueous solutions of κ-, ι-, β- and θ-carrageenans undergo the thermoreversible gelation by lowering temperature, whereas the aqueous solution of λ-carrageenan forms no gel.Light scattering and small-angle X-ray scattering were observed from the aqueous solution of κ-, ι-, λ-, β- and θ-carrageenans, and the results were analyzed conventionally and by adapting the molecular model in order to elucidate the effect of sulfate groups and anhydrous residue on the conformational characteristics of carrageenans.

植物種子由来キシログルカンの多様性と汎用性を、Tamarindus indica と Detarium senegalense Gmelin を例にとって総説する。植物種子由来キシログルカンは、いずれもセルロース骨格で構成される同様な一次構造をもっている。Tamarindus indica と Detarium senegalense Gmelin 種子粉末は食品添加剤として日常的に食されているが、私たちの体に及ぼす生理的効果は植物種により異なる。キシログルカンのモノマー単位は3タイプある。従ってキシログルカンの生理的機能は、異なるモノマーの並び方によって決まる高次構造に依存すると考えられる。光散乱と小角X線散乱は、キシログルカンの溶液中の構造を調べる有力な手段である。まずキシログルカンの溶液中の構造を調べる方法について述べる。光散乱と小角X線散乱の解析結果は、Tamarindus indica は本質的に直鎖状多糖であるのに反し、Detarium senegalense Gmelin は分岐構造をもっている可能性を示唆する。

New series of tri-sulfated (τ-carrageenan) and tetra-sulfated (ρ-carrageenan) carrageenans were prepared by the sulfating reaction from ι-carrageenan. The chain conformations of new carrageenans in aqueous solutions were investigated in the presence of various metal salts by means of static/dynamic light scattering and small-angle X-ray scattering, and their conformational characteristics were discussed with respect to the gelation behaviour. Although the overall conformation of newly prepared carrageenans is specified as a random coil, the local chain retains a rigid-rod-like structure by forming a helical conformation. The sulfate groups on C2 of (1→3)-linked β-D-galactoses were found primarily responsible to prevent gelation.

The cascade model for randomly branched f-functional polycondensates incorporated in Debye–Bueche random-two-phase model and the interference term by the interdomain interaction was found to good fit the small-angle X-ray scattering profiles of physically cross-linked amphiphilic elastomers. The samples were poly(oxyethylene)-grafted butyl rubber, butyl rubber with D-maltose derivative as pendant groups, and microcrystalline ionene elastomer composed of poly(oxytetramethylene) and 4, 4′-bipyridinium unit. The hydrophilic segments of these amphiphilic elastomers aggregated in the flexible polymer matrix to form the domains that function as cross-linking sites and fillers. Good fitting for all samples by using the proposed model gave the size of the physically aggregated domains, the average distance between the centers of neighboring aggregated domains and the their interdomain interaction distance. All samples were found to be in the vicinity of the gel point from the viewpoint of the cascade model. The r...

Thermally stable hydrogels have been prepared starting from aqueous gellan physical gels by partial self-cross-linking of the polysaccharide chains (formation of essentially interchain ester bonds, with no added bridging moieties) with the aid of the water-soluble 1-ethyl-3-[3-(dimethylammino)propyl]carbodiimide (EDC). The structure of the hydrated networksphysicochemical gelswas analyzed on the basis of the results of small-angle X-ray scattering experiments. Here a molecular model, which is composed of a bundle of 48 gellan double helices aligned in parallel, was proposed to represent the ordered domains in the hydrogels. The rigid bundles formed by associated gellan double helices constitute the junction zones which sustain the overall gel structure displaying solidlike properties. Relatively large cavities supported by rigid bundles inside the gels absorb water quickly as indicated by kinetic water uptake data. A network structure formed by rigid microfibrils of associated gellan double helices connec...