The viscoelastic properties of polyester films, crystallized by heat treatment at various temperatures, were measured in the phenol solution of several concentrations.
Dynamic modulus, E′ of polyester films and the apparent glass transition temperature determined from the peak temperature of E″ curve decreased with increasing in the concentration of phenol solution.
The dynamic modulus of amorphous region of polymer, E_A were calculated using the theory of mixed bicomponent polymer system. E_A′ against concentration of phenol solution curves obtained for each temperature could be superimposed by shifting the curves along the concentration axis. It was suggested that the decrease in E_A′ by the sorption of phenol was equivalent to the decrease in E_A′ by the increase in temperature for each sample film. The relationship between shifting value Δc and temperature depends on crystallinity of sample films. It was related with the difference of the internal fine structure of films.

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The effects of degree of polymerization, remaining catalyst, varieties of end group, and aftertreatment of polymer on the thermal degradation behavior of nylon 4 have been investigated.
From the weight loss data obtained by thermogravimetry under the condition of the temperatures ranging from 250 to 325°C (3 mmHg, N₂), 24.0 kcal/mole was obtained as the value of activation energy of thermal degradation for nylon 4 having η sp/C of 0.68. This value suggests that nylon 4, which prepared using two different types of antiators in this experiment is much less thermally stable than commercial fibers. The molecular weight dependency on thermal degradation was observed markedly, at the same time it was proved that the relative thermal stability of nylon 4 should be exactly estimated the amount of remaining catalyst and of oligomer. Although a formation of α-pyrrolidone by thermal degradation reaction occurred predominantly at the end of polymer, it was presumed that the reaction occurred also at the main chain of polymer when the degradation temperature was higher than 300°C or the molecular weight of polymer was appreciably low.
A slight decrease in thermal degradation was observed by after-treatments due to the removal of remaining catalyst and oligomer from polymer, however the marked improvement for thermal stability of nylon 4 has hardly obtained.

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Photo-induced graft polymerization of methyl methacrylate onto mesyl cellulose has been studied with and without azobisisobutylonitrile (AIBN). The graft polymerization in the absence of AIBN proceeds mainly via the photolysis of mesyl cellulose. Since using a quartz tube may result in the scission of cellulose molecule, the grafting also occurs at the end of cellulose. The graft polymerization in the presence of AIBN takes place not only by the photolysis of mesyl cellulose but also by the chain transfer of homo polymer to the trank polymer. The graft polymerization with AIBN starts at lower temperature than without AIBN. The termination is caused by the reaction between cellulose radicals and growing polymer radicals. As a small amount of dimethylformamide solution is added in the polymerization system, the affinity between mesyl cellulose and monomer increases, and owing to this reason the degree of grafting and the number of grafted chains increase. The photolysis of mesyl cellulose was also investigated by the I. R. spectra.

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Pressure effect on the diffusion coefficient D of nine disperse dyes in poly (ethylene terephthalate) (PET) sheet was investigated at 130°C under pressures up to 1kbar by the multiple membrane method. The values of In D showed linear decrease with increasing pressure, giving the activation volume ΔV_??_ for diffusion, 64-123cm³/mol for p-nitroaniline (pNA) and C. I. Disperse Blue 1 (DBl), respectively. The molecular volumes of the penetrants in crystalline state were evaluated from the density measurements, x-ray data and the van der Waals contact models of the molecules. For example, the molecular volumes of pNA and DB1 were 99 and 182 cm³/mol, respectively. The results of ΔV_??_ were now compared with the molecular volumes of the penetrants. It was found that ΔV_??_ increased almost linearly with increasing molecular volume. It was further demonstrated that the anthraquinone derivatives needed larger ΔV_??_ than the azo derivatives compared at the same molecular volume. These as well as the differences between the observed ΔV_??_ and the molecular volumes of the penetrants were discussed from the viewpoint of the free volume theory.

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In a previous paper, the improvement in wet fastness of acid dyes on nylon fiber by aftertreatment with tannic acid (backtanning) was investigated. From the results obtained by the diffusion of dyes in the nylon film treated with tannic acid prior to the experiment, it was deduced that the improvement might be attributed to suppression of dye diffusion by the electrostatic repulsion between dye and tannic acid and the filling up of voids in nylon by tannic acid.
In this paper, the effect of electrostatic interaction between dye and tannic acid on the dye fixation was investigated by measurement of desorption rate of dye from nylon 6 fiber backtanned after dyeing in practical convention and further by microscopic observation of distributions of dye and tannic acid in the fiber. Four disperse, 10 acid, 1 direct and 4 basic dyes were used in this experiment.
The informations obtained are as follows:
1) The wet fastness of these dyes on the fibers is improved by backtanning and further by a successive treatment with tartar emetic (full backtanning).
2) The anionic (acid and direct) dyes, which are adsorbed in skin layer of the fiber, are moved into core by backtanning and then tannic acid is adsorbed in the skin layer. Consequently, tannic acid is concentrated at surface layer of the skin, and the dyes, especially those having two or more sulfonic groups, are fixed effectively. This may support the favorable effect of electrostatic repulsion between the dye anion and tannic acid on the dye fixation.
3) In the case of nonionic (disperse) dye, considerable amount of tannic acid easily permeates into the dyed fiber and simultaneously the dye appreciably bleeds out during the backtanning because of the absence of electrostatic interaction between the dye and tannic acid. Therefore, the fixation effect for nonionic dye seems to be not so remarkable.
4) The cationic (basic) dye forms a lake with tannic acid by electrostatic attraction and it is deposited in the skin layer of the dyed fiber. It brings unfavorable desorption of dye and decreases fairly the fixation effect.

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For polyester filament threads applied with silicone oil of single component, the sewability and slipperiness were evaluated from the maximum speed of sewing machine and the frictional coefficient, respectively. Sewability was the lowest at 0 percent of the lubricant application. It was abruptly improved in the 0_??_0.5 percent range and kept the highest level above 1.0 percent. The frictional coefficient, which measures the slipperiness of the thread, assumed the highest value at 0 percent application, decreased abruptly in the 0_??_0.5 percent range and kept the lowest level above 1.0 percent. The sewability was suppressed with an increase of the frictional coefficient.

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