The effect of the curing conditions on the physical properties and the crosslinking structure of cotton fabrics treated with dimethylol ethylene urea was studied.
The dry crease recovery angle (DCRA) was related to not only the product of the root of the crosslinking length and the number of crosslinks, but also the degree of the completion of crosslinkage. It was also substantially affected by the hydrogen bond effect. Wet crease recovery angle (WCRA) was related to the product of the crosslinking length, the number of crosslinks, and the degree of the completion of crosslinkage. WCRA was also affected by the fiber's swelling property. In addition, the strength loss was found to be caused by the degradation of cellulose molecules, and the stiffness formed by crosslinkage. This strength loss caused by the stiffness was related almost linearly to the product of the number of crosslinks and the degree of the completion of crosslinkage in all curing conditions.

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The interaction between moisture and cellulose was investigated by pulsed proton broadline NMR spectroscopy. Five kinds of cellulosic fibers; such as scoured ramie, scoured cotton, mercerized cotton, normal viscose rayon, and high-tenacity rayon, were used as test specimens differing in the degree of crystallinity as widely as possible. The specimens were conditioned at various relative humidities from dryness up to saturation at 30°C. The investigation was performed by resolving the proton free induction decay signal into three different j's relaxation processes with fractional initial intensities, A_j, and spin-spin relaxation times, T_{2, j}: i.e., a fast decay process shown as A_s and T_{2, s}, and two slow decay processes shown as A_m and T_{2, m} and A_l and T_{2, l}.
The relaxation times, T_{2, s}, T_{2, m}, and T_{2, l}, were found to be in the orders of several μsec, several hundred μsec, and several msec, respectively, according to the amount of moisture sorbed in the specimens. The results enabled us to assign the relaxation processes to the motion of protons of cellulose and tightly bound water, of bound water, and of loosely bound water, respectively.
Subtracting the water proton contents determined from the values of A_m and A_l, from total water proton content determined from the moisture sorption isotherm of the specimen, the value of A_{s, w} for the tightly bound water was estimated as a function of relative humidity. The results also enabled us to resolve the isotherm of each specimen into three components attributed to the tightly bound water, bound water, and loosely bound water.
The three components of the isotherm were discussed with reference to the analysis of the isotherm in terms of the B. E. T.'s multilayer adsorption of finite number of layers, n, deducing the following conclusions: 1) sum of the resolved isotherms of the tightly bound water and the bound water accords with the Langmuir's monolayer adsorption with n=1; 2) the resolved isotherm of the loosely bound water corresponds to the B. E. T.'s multilayer adsorption with n_max_??_n>1; but 3) no distinction between n_max_??_n>1 and n>n_max is achieved.

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For the porous membranes of nylon-66, the sorption effects of alkaline-earth metal ions on the melting behaviors were investigated by differential scanning calorimetry (DSC) and were compared with the methoxymethylation effects. In the case of the membranes annealed at a high temperature above 235°C, it was found that sorbed calcium and magnesium ions suppressed recrystallization and reorganization of crystalline regions during DSC heating process similarly to the case of methoxymethyl residue. The starting temperature of melting was almost equal to the annealing temperature. The sorption of sodium and potassium ions gave no change on DSC curves, except for the depression of the melting peak temperature within 2_??_3° resulting from the dilution effect. In the methoxymethylated nylon-66 membranes, the relationship between the melting peak temperature and the composition was explained very well by the modified Flory's equation (1) of random copolymers.

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A mixture of poly (ether sulphone) (PES) and poly (ethylene oxide) (PEO) exhibits LCST (lower critical solution temperature) behavior; i.e., they are miscible at low temperatures but immiscible at high temperatures. Of this polymer-polymer pair, we prepared two series of blend specimens; one was a single-phase system and the other was a phase-decomposed one. The latter system was obtained by annealing the former at above LCST and rapid-quenching at below glass transition temperature.
Surface tensions of the blends were estimated by measuring liquid contact angle. The phasedecomposed system showed higher surface tension than the single phase system. This difference was shown to be caused by the increase of polar and hydrogen bond components in surface tension with phase-decomposition. By Fourier-transform infrared spectroscopy this phenomenon was ascribed to the dissociation of the hydrogen bonding type interaction between PES and PEO in the single phase system.

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A new method has been developed for acetylating cellulose using acetic acid. It has been found that cellulose is easily acetylated by acetic acid (AcOH) with the system of pyridine (Py) containing p-toluenesulfonyl chloride (TsCl) or Methanesulfonyl chloride (MsCl). Especially, rayon was acetylated to about 3.0 of D. S. within 2hr at 50°C by this system. The ratio of TsCl and AcOH was found to be an important factor for this reaction. When the equimolar ratio of TsCl and AcOH was used, the reaction proceeded most rapidly. Infrared spectra of the cellulose acetates obtained were also investigated.

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As a factor affecting the hard-twist yarn's physical properties during heat set, the heat transfer of a yarn package was studied with a simple model.
The simple model used regards the yarn package as the complex of yarn and air without radiation and convection, and implies the effect of barrel to the heat transfer coefficient of inner side.
The results obtained are as follows:
(1) Heat transfer of the yarn package in dry air is able to analyze with the simple model. On the other hand, heat transfer in humid air is difficult to analyze only with the simple model because of humid air's diffusion in the yarn package. But, this method is useful to predict the behavior of yarn that forms the yarn package.
(2) Irregularity of hard-twist yarn's physical properties that appears during heat set is caused by obstruction of shrinking by barrel, difference in temperature rise and irregularity of relaxation of winding tension.

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The foam dyeing apparatus has been developed for the saving of water and/or energy-saving in dyeing processes, the reduction of contamination of natural environment by the waste fluid, and the prevention of injury or damage of dyeing substrates. Consequently, the physical function that damages dyeing substrate is reduced, and extremely low bath ratio is realized, further the energy needed in heating up is diminished.
In this report, the application of the foam dyeing method to the woolen fabric-acid dye system, and the investigation of the dyeing property, the blow ratio, the foaming property of the bulk liquid or the foam stability, and the dye content of the foam film were carried out, and following results have been obtained:
1) A dye uptake of fabric was increased with the reduction of the bath ratio. This might be considered that a dye concentration in the bulk liquid is more concentrated as a results of decrease of bath ratio.
2) The good dyeing property was brought by the use of the foaming agent characterized by its rather hydrophobic property. But the cloud point of the bulk liquid must be taken into consideration from the viewpoint of the foaming property and foam stability.
3) The dye content of the foam film was slightly lower than that of the bulk liquid, though the correction of the dye content could be simply done by the addition of dye to the bulk liquid conforming to a linear calibration curve.
4) In the foam dyeing method, a foam was formed continuously and rose into the cylindrical dye-bath, the dyeing substrate was initially wetted by the foam, and dye molecule transported by the foam film was adsorbed on the substrate-liquid interface, and it was uniformly diffused into the substrate under the appropriate dyeing condition; 3l/min of the air flow rate, 2.0 to 2.5% region of acetic acid content, at 80°C, and for 30min.

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