Granular polypropylene polymer dissolved in toluene was spread on glass plate and after the evaporation of the solvent the polymer was melted at 180°C and then supercooled. From this sample the spherulitic film (larger part is consisted of spherulite) was obtained after the heat-treatment for 100 min. at 130°C. Drawn film was prepared by stretching the spherulitic film at the speed of 110%/min. at 130°C. The effects of the temperature on the stresses of these two kinds of films were examined under equilibrium conditions.
(1) Restoring forces, f, developed in the range of less than 2% lower elongation consist of two parts of contributions, that is, enthalpy term, and correction term on the length at varying temperatures. Entropy term at constant length, which may be considered due to the change in molecular configurations, may be neglected. Thus the expression between the restoring force and the temperature may be expressed: where l is length, β the coefficient of linear expansion of the film, P pressure, f stress, H enthalpy, γ elongation and T temperature.
(2) Both the spherulitic and drawn films, which are equal in crystallinity, obey the linear relation between stress and temperature cited above. Deviation observed above 80°C become more serious in the drawn film than in the spherulitic one. This may be caused by any transition of crystalline parts. The abrupt deviation observed in drawn film may be due to the orientation of molecular chains in the drawing process.

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Tentering of milled felt was studied. Relations between changes of area of felt by tentering and breaking strength, breaking extention and splitting resistance were examined. Breaking strength of the felt increases by tentering, and the increase was especially pronounced in the early stage of tentering, but it tends to decrease in the later stage of tentering. Splitting resistance and breaking extention decreases by tentering, and the decrease is pronounced in the early stage of tentering.
Experimental results may be explained by assuming that breaking strength and splitting resistance are mainly affected by both the degrees of entanglement of fibers and the fiber orientation. Where it is suggested that the increasing degree of tentering increases the degree of fiber orientation in two dimentional direction, and decrease the orientation in the vertical direction and decrease the degree of entanglement of wool fibers.

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A tester (Fig. 1.) was designed to measure the torque and tension generated when the slubbing is twisted under a constant length or constant tension.
Using this tester, the mechanism of false twisting system, which controls drafting by frictional twisting between twister tube and slubbing, was investigated. Some results are shown in Fig. 2_??_Fig. 6.
The twist turns which are inserted is decided by the balance between the moment of false twister and the torque of sliver. These relation were analyzed theoretically in equations (4)_??_(7). The theory is applied to the results of the experiment on thread angle and sliver thickness in the preceding pa_??_er (V).

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Various methods for the preparation of cellulose acrylic-acetic mixed acid esters were investigated.
(1) Celluloses pretreated with 40% aqueous solution of CH₃COOK or CH₂=CHCOOK were treated with a mixture of CH₃COOH, (CH₃CO)₂O, CH₂=CHCOOH and a diluent at 120°C. Three to fourteen weight % of acrylic acid ester groups were introduced together with the acetic acid groups.
(2) Celluloses were treated with a mixture of CH₃COOH, (CH₃CO)₂O, CH₂=CHCOOH, a diluent and H₂SO₄ as catalyst. No acrylic acid ester groups were found in the reaction product.
(3) Cellulose di-or tri-acetates were hydrolyzed in 90-95% aqueous solution of CH₂=CHCOOH with 0.1-0.5% HCl as catalyst. A small amount (ca. 2.6%) of acrylic acid ester groups were introduced.
(4) Celluloses impregnated with 40% CH₃COOK aqueous solution were treated with (CH₂=CHCO)₂O in a diluent. A large amount of acrylic acid ester groups (ca. 30%) were introduced.
(5) Celluloses were treated with a mixture of (CH₃CO)₂O, CH₃COOH, (CH₂=CHCO)₂O and CH₂=CHCOOH with H₂SO₄ as catalyst. The mixed cellulose esters containing 10-20% of acrylic ester groups and 30-35% of acetic acid ester groups which are soluble in organic solvents were obtained.
The IR spectra of pure cellulose acrylate were compared with those of cellulose acetate. The absorption bands of 1635, 1410, 1300, 1195, 980 and 807 cm^-1 were observed in cellulose acrylate, while they were absent in the cellulose acetate. The absorption at 807 cm^-1 was used as a qualitative characteristic measure for the presence of cellulose acrylate.

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Petroleum resin was nitrated with fuming nitric acid and reduced with metallic tin and hydrochloric acid to give aminated petroleum resin. The resulting aminated petroleum resin hydrochloride, which has 6_??_7% of nitrogen content, is soluble in water.
It was found that the amino-resin hydrochloride does not have sizing effect but excellent sizefixing effect on paper. When the amino-resin hydrochloride and ordinary commercial petroleum resin size are applied to paper making, the sizing effect of the petroleum resin on paper is improved by the fixing action of the amino-resin, and especially the sizing effect estimated by ink-floating method is remarkably elevated. The sizing effect is found on the ordinary paper as well as on that having calcium carbonate as a filler.
The amino-resin hydrochloride is diazotized and an azo dye was formed on fiber by coupling with Naphthol AS-OL. Nylon and cotton are coloured in this way, giving light brown shade of good fastness.

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The effects of the fluorination degree on the dyeing behavior were investigated on polypropylene fiber.
The penetration of basic dyes into fluorinated fibers has been measured by microscopic observation of the fiber cross-section.
A plot of the distance λ_x of penetration against the square root of the dyeing time gives the, straight lines which do not pass through the origin, but intercept the time axis. This suggests the presence of a thin membrane of low permeability covering the fluorinated polypropylene fiber. The rate of penetration into the thin membrane was found to decrease by increasing the fluorination degree of the fiber. Consideration on the penetration coefficient P_x, given by the square of the slope, however, leads to the conclusion that the diffusion of the dye within the fiber is independent on the fluorination. Which occures selectively on the surface of the fiber. The highly fluorinated surface layer of the fiber might correspond to the thin membrane of low permeability.
The rate of penetration of dye within the fiber increases with increased pH of the dye-bath.
The exhaustion vs. time curves determined indicates that the exhaustion takes place at two distinct stages, an initial very rapid exhaustion on the outer surface of the fiber which might be due to negative zeta potential of the fluorinated polypropylene fiber being followed by much slower exhaustion and penetration into the fiber.
From these results it may be concluded that the dyeing of fluorinated polypropylene fiber with basic dyes must involve three stages, namely: (1) At the start of the dyeing process dye is removed rapidly from the solution and transfers to the outer surface of the fiber, (2) Dye diffuses in the highly fluorinated thin membrane of low permeability, (3) Dye diffuses within rhe fiber.

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