The chain conformations of polyethylene (PE), polypropylene (PP), poly (vinyl chloride) (PVC), polystyrene (PS), and poly (methyl methacrylate) (PMMA) were analyzed by MM2 (91) in which oligomeric model compounds composed of several repeating units were used as the initial structures. The optimized steric structures of the model compounds were found to correlate with those of the extended chains of the original polymers both in the crystalline and amorphous states. Therefore, these structures were used for estimating the values of birefringence of the polymers, for which a new program called MBES was newly developed. It was found that the resulting values of birefringence based on the structural data of MM2 are more reliable than those calculated by the conventional estimation method, especially for amorphous polymers.

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The preparation of cellulose esters with aromatic carboxylic (substituted benzoic) acids in the presence of p-toluenesulfonyl chloride (TsCl) in pyridine (Py) was investigated. Cellulose was readily acylated with substituted benzoic acids, such as nitro-, chloro-, methyl- and methoxybenzoic acid, by use of the Py/ TsCl/ acid system, and corresponding cellulose esters with high degrees of substitution (DS) were obtained. The difference among the substituents and among the isomers (o, m- and p-isomers) of the acid did not influence the reaction significantly. With an amino-substituted benzoic (p-aminobenzoic) acid, the cellulose ester could not be obtained, because acylation of the NH₂ group with the other p-aminobenzoic acid took place in preference to the OH group of cellulose. When the NH₂ group was protected with a methyl group, on the other hand, the corresponding ester was obtained by this method.

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The surfaces of corona-treated cellulose fibre sheets were characterized by a chemical modification in gas phase-ESCA technique. Whatman #1 filter paper, handsheets from softwood bleached sulfate pulp (N•BKP), handsheets from hardwood bleached sulfate pulp (L•BKP) and handsheets from thermomechanical pulp (TMP) were prepared as cellulose fibre sheet samples. The following results were obtained. (1) Corona-treated cellulose fibre sheets were chemically modified (derivatized) in gas phase by pentafluorophenylhydrazine (PFPH) or trifluoroethanol (TFE), and ESCA spectra of the derivatized sheets were examined. The results show that carbonyl and carboxyl groups were formed on the surface of the cellulose fibre sheets. (2) The quantity of the introduced carbonyl and carboxyl groups, which were obtained by derivatization in gas phase, was larger than those obtained by derivatization in liquid phase. Furthermore, the quantities of the functional groups formed on the surface of the sheets by derivatization in gas phase after washing with some organic solvents and those by washing with organic solvents after derivatization were found to be less than those derivatizing only in gas phase. These results suggest that carbonyl and carboxyl groups were introduced onto the framework or main chain in the surface layer of the sheets. At that time, depolymerization occurs in the framework and the resulting fragmental low molecular compounds have carbonyl and carboxyl groups. (3) The total concentration of the carbonyl and carboxyl groups in the ethanol extracts from the corona-treated sheet were determined by oxime formation and hydroxamic acid-Fe chelate complex formation method, respectively. The increase of 0.98% in the carboxyl group for Whatman #1 filter paper and that of 0.58% for TMP handsheet were found, compared with those of untreated sheets. The increase of 0.02% in the carboxyl group for the Whatman #1 filter paper and that of 0.04% for the TMP handsheet were also found. These results indicate that the low molecular compounds were formed by corona discharge and the compounds possess carbonyl or carboxyl groups.

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Solvolysis pulps (CWPs) were prepared from two species of softwoods using the cresol-water system. The crystallinity, degree of polymerization (DP) and α-cellulose content of the CWPs were measured to elucidate the influence of delignification with sodium chlorite on the physicochemical properties of CWP. X-ray diffractograms revealed that the crystalline regions of CWPs maintained the cellulose I structure. An increase in the crystallinity of CWPs with increasing delignification was observed by X-ray diffraction and ¹³C-CP/MAS NMR studies. A further delignification brought about a slight destruction of the crystalline regions. DP was decreased significantly at the initial stage of the delignification and then was gradually decreased. α-Cellulose content of the delignified pulp was also reduced slightly at the final stage. A similar tendency was observed for commercial unbleached kraft pulp and sulfite pulp which underwent the same treatment. These results suggested that the amorphous regions of unbleached pulps were destroyed during the delignification treatment due to the acidic medium follwed by collapse of the crystalline regions.

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A new technique of topographic scanning scanning electron microscopy was used to study the influence of tracking with the stylus on contact profilometry of paper surface. Microscopically determined profile curves were analyzed in terms of Fourier components. By selecting a wavelength range below a cut-off wavelength, the profile change caused by the tracking with the stylus was detected effectively. With an optimal cut-off wavelength of 16μm, the deformation of the surface of a woodfree paper by stylus tracking was clearly shown. This cut-off wavelength corresponds to three times of the radius of curvature of the stylus tip.

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The effect of methylacrylate (MA) on dyeing acrylonitrile/MA copolymer fibers with cationic and disperse dyes was studied at equilibrium. The fibers were spun from copolymers having MA content varied from 2 to 14% by weight and were found to increase with increasing MA content. Irrespective of MA content, saturation values for the cationic dyes became equivalent to the content of the strong acid group of the fibers. The weight fraction of the fiber structures molten at the heat-treating temperatures, mf (T), was calculated according to the kinetics of copolymerization and the depression of melting temperature as a function of the AN sequence. The increasing behavior of the partition coefficient for the disperse dyes has heen satisfactorily interpreted on the basis that the internal volume for the disperse dyeing increases by the molten volume increment calculated from mf (T).

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The gravitational effect on the forced bending vibration of a fabric strip was studied experimentally and analytically. The transfer function of the vibration and the eigen frequency of the fabric were measured by the vibrating reed method with a sweep oscillation device. The equation of motion of a vibrating reed in the gravitational field was derived, on the basis of which the eigen frequency and vibration mode of the reed were analyzed by a finite-element method for two situations with and without taking into account the gravity effect. Through these works, it was found that, for soft materials as fabrics. vibration could be appreciably affected by gravity, the degree of which increased with the ratio of the sample length to the bending length defined by the cantilever technique for stiffness measurement

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A new method for produsing replicas of pores in porous acrylic fibers has been developed for transmission electron microscopy. The method involved filling the pores with styrene followed by its polymerization. The resulting fibers impregnated with polystyrene were microtomed into sections of thickness of ca. 70nm, from which acrylic part was removed by extraction with dimethyl sulfoxide. This procedure resulted in pore replicas with minimum of artifacts. Application of this method to the wet spun acrylic fibers revealed morphology of the internal pore networks which were slightly oriented along the fiber axis.

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