Thermal degradation and solid-state polymerization of poly-trans-4-γ-propoxycyclohexyl amide (PPCA) were investigated. From the results of thermal gravimetric analysis with the multiple heating rates method, the activation energy for thermal degradation reaction of PPCA was found to be 53.7kcal/mole, and this value was essentially identical with that obtained from the investigation at the constant temperatures between 340 and 380°C (51.7kcal/mole; in vacuo, 48.1kcal/mole, in N₂). The small value of activation energy (37.7kcal/mole) for a first stage of degradation suggests that PPCA is thermally unstable.
The activation energy for solid-state polymerization of PPCA at the temperature from 170 to 230°C was found to be a small value 10.7kcal/mole, this indicates a high mobility of polymer chain at this temperature range. The results are in good agreement with the consideration being described in the previous paper for relationship between the high value of T_g/T_m (0.73, °K/°K) and the chemical structure of PPCA.

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Preparing of polypeptide fibers having the excellent characteristics of both poly(methyl glutamate) (PMG) and poly(glutamic acid) (PGA) fibers was examined, and the following results were obtained.
(1) By uniformly saponifying PMG fiber, a uniform (methyl glutamate-glutamic acid) copolymer fiber was obtained, and the water-sorptive capacity and the dyeability were improved without serious deterioration of mechanical properties. By surface saponifying PMG fiber, which yielded a continuous composite fiber of copolymer of surface part and PMG of core part, especially the wet strength and the wet modulus were much improved.
(2) The tensile strength of polypeptide fibers depended more on the content of β-form structure than on the degree of molecular orientation.
(3) The water vapor sorption of fiber was higher than that of membrane, because of the β-form structure of fiber.
(4) The water sorption process in the β-form structure may be described as follows: water molecules are sorbed on free polar groups of main chain at low relative vapor pressure, and hydrogen bonds between polar groups in the main chain are in some extent broken at the higher relative vapor pressure for water molecules to be absorbed on those parts.

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A study on the dyeing behavior of an acid dye on extended and unstretched wool fibers was made in connection with the structural transformation of the fibers. It was observed that in a pH range between 4 and 6 remarkable differences in dye uptake for extended and unstretched fibers were obvious and the extended fibers adsorbed a larger amount of the dye compared to unstretched fibers do at the same pH. It was suggested that this result was attributable to changes of dissociation constant(s) and/or micro-environment of dissociative groups of wool fiber. Furthermore, the amount of dye uptake increased with increasing the extent of extension up to 50% and the amount of dye uptake reached a constant value at extensions beyond 50%. It was recognized that these dyeing behaviors were correlated with the structural transformation of wool fiber from α- to β-form.

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Gas chromatographic behavior of cotton fiber, as column stationary phase, was investigated by injecting water as probe. The retention volume decreased with temperature over a range of 70-120°C, while it decreased with increasing the probe size until a point of inflexion then increased linearly with larger sample size. Carrier gas flow rate did not affect the amount of sorption at 90°C. Though the amount of sorption by inverse gas chromatography was slightly smaller than that by static method, a reasonable agreement of BET constants suggested that inverse gas chromatography was useful for determination of adsorption isotherm even below T_g BET monolayer capacity corresponded to the amount of sorption at a point of inflexion with regard to flow rate of 20ml/min and 40ml/min, adsorption monolayer was formed around this point and multilayer adsorption occurred at higher probe concentration.

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Deterioration of filaments and films of polyethyleneterephthalate were investigated with crude enzyme solutions of Cladosporium cladosporioides FERM J-8. The test pieces of filaments or films were immersed at given pH (5.5, 7.0, 8.0) in the enzyme solutions prepared from the fungus. The mixture was shaken at 30°C for two weeks. The incubated samples were observed by scanning electron micrography and some physical properties of the filaments or films were examined. Furthermore, the chemical changes of the filaments or films and the liberations of carboxyl group and ammonia were measured.
The tensile strength, viscoelasticity, extension behavior and relative viscosity were remarkably changed. It was recognized that these changes were caused by the hydrolysis with esterase of Clad. cladosporioides. This deterioration phenomena was not the swelling soluble type such as Nylon-6, Diacetate, Cotton cellulose and Silk fibroin. But, it has a similar property of Polyurethane, Triacetate and Diacetate filter. As the above result, it was considered that the lyric mechanism was almost same as the action of the organic bases or ammonia.

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Poly[ethylene 3, 3'-ethylenedioxy dibenzoic acid] (m-Ph) was prepared by polycondensation, and its thermal properties, crystallinity, and mechanical properties for melt spun fibers were investigated. m-Ph containing the m-phenylene groups was difficult to crystallize, however the stretched filaments showed slightly crystallized and oriented x-ray diffraction patterns. Intrinsic viscosity [η] of m-Ph was 0.61 in phenol-tetrachlorethane mixed solvent (1/1 wt) at 25°C. Glass transition temperature of amorphous sample of m-Ph was 44°C (DSC) and melting temperature of annealed sample was 151°C (DSC).

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