The properties of the dope solution of acrylonitrile-methyl acrylate copolymer of 0.95 to 0.05 which was prepared by 50% aqueous solution of NaCNS were studied.
(1) The specific gravity of the dope was measured at 30°C in the concentration range from 0.63% to 11.93%.
(2) Hygroscopic behaviours of the 50% aqueous solution of NaCNS and the dope sulution with the polymer concentration of 9.5% were measured and compared at the relative humidity of 60% and at 25°C.
(3) Microscopic measurement was utilized to evaluate the dissolving rate of acrylonitrile fiber and polymer particle. The minimum concentration of NaCNS to dissolve the polymer is presumed to be around 46%.
(4) The viscosity of the dope solution was measured by the ball fall method in the polymer concentration range from 7% to 13%, and in the temperature range from 0.8°C to 65°C. At 30°C, the modified Baker equation obtained is as follows.
where η is the viscosity (sec.), M: molecular weight obtained by using the Staudinger equation, η_BP/C=1.5×10^-4M (C: 0.5 mole/l), C: the polymer concentration of the dope (%).
(5) A linear relationship was observed between the logarithm of the viscosity and the recipr ocal of the absolute temperature in the temperature range from 30°C to 65°C. This relationship did not hold at the temperature below 10°C.
(6) The Copolymers of different molecular weights were mixed in various ratios to prepare six dope solutions of the copolymer mixture and the viscosity of the solutions were measured.
The relationship of the viscosity of each of the original polymer solution to those of the mixed polymer solutions may be expresed as: where η: the viscosity of the mixed polymer solution (sec.), η₁: the viscosities of the original polymer solutions (sec.), W₁: the weight fractions of the original polymer solutions (%).

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Co-polymer composed of AN 95% and methyl acrylate 5% was dissolved into NaCNS aqueous solution of 50% concentration. This dope solution was extruded in NaCNS aqueous solution of 10% concentration at the temperature levels of 0°C, 10°C, and 20°C, and with the spinning velocity of 30_??_50m/min. Coagulated yarn thus obtained was processed through water washing, and then hot-water stretching.
Tensile properties of the coagulated yarn and the final fiber were measured at each process.
1. The lower the temperature of the coagulation bath is, the higher the tensile strength and the resistant energy or rupture (tensile strength elongation) of the yarn in the coagulation on process and also in the following the yarn washing and hot stretching processes. The same tendency is noticed in the tensile strength of the final fiber.
2. When the temperature of coagulation bath was 0°C, the strength of yarn which went through the coagulation bath, washing bath and hot stretch bath was 0.21g/d, 0.32g/d, and 3.30g/d, respectively.
3. The increasing ratios of the strength at each processes were almost constant independent on the temperature of coagulation bath in the range of 0°C_??_20°C, except for one case.
4. No influence of the temperature of washing water on the tensile properties of the final fiber is observed in the temperature range from 10°C to 30°C.
5. when the coagulated yarn in the gel state is stretched to increase the eveness of coagulation, about two-times stretch is desirable from the view point of moleculhr sliding by stretching.
6. The coagulation at 0°C and stretching about 10 times in boiling water resulted the favourable tensile properties of final yarn such as tensile strength 3-4g/d, knot strength about 2.8g/d, and elongation about 30%. If glycerin aqueous solution is used in hot stretch process, 14 times stretch is feasible at 130°C.

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The monoclinic crystal birefringence of isotactic polypropylene was evaluated on a basis of the simple addivity as given by where Δn is measured birefringence, Δn^*_c is an intrinsic birefringence of monoclinic crystal, Δn^*_a is that of amorphous chain, F_c is uniaxial orientation factor of the c-axis of monoclinic crystal to the fiber axis, F_a is that of the amorphous chain also to the fiber axis, X_v is degree of crystallinity (volume faction), and ΔF is form birefringence.
The value of F_c was evaluated by means of Wilchinsky's method from the azimuthal intensity distributions of the (110) and (040) X-ray reflections. The values of Δn and X_v were measured by Berek's compensator and density gradient tube techniques, respectively. The specimens used were sufficiently annealed so that the crystalline phase consisted wholly of monoclinic crystals.
When assumed that the value of F_a is equal to zero for the low oriented specimens having the value of Δn less than 10×10^-3, the value of Δn^*_c is estimated as 41.5×10^-3, while assumed that the value of F_a is identical to that of F_c and Δn is inversely proportional to the density, the value of Δn^*_c is estimated as 39.0×10^-3 for the highly oriented specimens having the value of Δn from 24×10^-3 to 35×10^-3.

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Properties of the Acrylamide-Grafted Cellophane were investigated. The study on the tensile strength and elongation of grafted cellophane showed that the flexibility decreases with graft ratio and that its flexibility increases with temperature at such high graft ratio as 265%, but it decreases with temperature at such low graft ratio as 100% or less.
The polyacrylamide in graft polymer seems to exist by forming strong networks as the secondary bonds, of cellulose in dry state. These networks are released and the tensile strength of the graft polymer decreases in wet state.
Furthermore, the structure and properties of grafted-cellophane is discussed from the results obtained on the heat treatment and the irradiation of ultraviolet rays.

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The number and the length of fibers in the formation of pilling are important factors. The paper describes the statistical treatment of these factors on the pills formed by T. O. pilling tester. For the convenience of discussion, the fibers which participate in the forming of pills are divied into two parts, i.e. part of fibers involved in the spherical entanglement (A) and that of fibers connecting the (A) with the surface of the fabric (B).
The results obtained are as follows:
(1) The mean length of fibers forming the part (A) may be expressed by where W is the total weight of the fibers forming the part (A) and(B); δ, the linear density of the fiber; N, the total number of fibers forming a pill and _??__b mean length of fibers in the part (B).
(2) The probability distribution of N and l_b can be approximated by the Poisson distribution over the time interval of rubbing selected in this study, and that of _??__a and between 10min. to 50min.
( 3) The mean values obtained from the distribution of the factors N, _??__a and l_b are plotted against the rubbing time and the results are discussed in relation to pilling tendency.

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The pilling tendency of a fabric may be associated with the fuzzing. To determine this tendency, the frequency distribution of fuzz length on the surface of the fabric is measured. Further, fuzz and fibers forming pills on the fabric are sheared and weighed.
The fuzz and pills on the fabric are formed by using the Random Tumble pilling tester (type T. O.).
The results obtained are as follows;
(1) By making the differences in regard to each frequency corresponding to the same length between the frequency diagram for fuzz length at rubbing time 10min. and that of 30min., the number and the length of fibers forming pills on the fabric during 10 and 30min. is discussed.
(2) The frequency distribution for the length of fibers forming pills is approximately given by the Poisson distribution.
(3) The relation between the pilling and the fuzzing on the surface of the test fabric may be discussed from the three expressions such as R₁, R₂ and R₃: where, t_i and t_i-1 are the rubbing time (t_i-1, <t_i, i=0, 1, 2, ……); [W^PF, Δt_i] weight of fibers forming pills, which were produced during short time Δt_i(=t_i-t_i-1); [W_FA, t_i-1] and [W_FA, t_i] weight of fuzz on the fabric measured at time t_i-1 and t_i; [W_PA, t_i] weight of fibers forming pills on the fabric measured at time t_i and [W_III, t_i] total weight of fuzz produced on the fabric and worn-off from the fabric at time t_i.

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The rate of removal of fatty soils from polyester and cellulose fabrics was studied by means of a radioactive-tracer technique in an attempt to find out the cause which decreases a whiteness of polyester fabrics during progressive washings.
Six redioactive typical fatty compounds such as stearic acid-l-C¹⁴, oleic acid-l-C¹⁴, tristearin-l-C¹⁴, stearyl alcohol-1-C¹⁴, cholesterol-4-C¹⁴, and octadecane-1-C¹⁴ were chosen from those obtained through Brown's chemical analysis of soils contained in those worn clothings.
Small samples of polyester and cellulose fabrics were soaked in the respective benzene solutions of C¹⁴ labeled compounds described above, dried at room temperature to evaporate the solvent, then washed at 50°C with the aqueous detergent solution at different times and dried.
Radioactivities of washed and unwashed fabric samples were then measured by means of Geiger-Müller end window counter. Thus, having corrected for the background count, the ratio of the count of the washed sample to that of the unwashed sample provids a measure of the proportion of the labeled fatty compound retaining on the sample.
By a contact method autoradiographs have also been made of several kinds of samples which were washed for 20 times after soiling.
The results obtained are as follows: (i) Soils on polyester fabrics are more difficult to be removed than those on cellulose fabrics. (ii) The rate of removal considerably differs with the types of fatty soils. Namely the rate increases in the order: tristearin stearyl alcohol cholesterol stearic acid oleic acid octadecane

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The diffusibility of soils into multi-layer polyester and cellulose films was studied by means of a radioactive-tracer technique and the following results were obtained:
(i) Into polyester film, considerable diffusion of soils was observed when the soiled films were heated to 105°C and more diffusion at 120°C, even though almost no diffusion of soils occurred after they have been allowed to stand for six months without heating. On the other hand, no diffusion into cellulose films was observed under the similar conditions.
(ii) The diffusibility considerably differed with the types of soils. Namely the degree of diffusion increases in the order:
tripalmitin tristearin carbon black palmitic acid stearyl alcohol stearic acid oleic acid cetyl alcohol cholesterol
(iii) It seems that fatty soils having a small molecular volume diffuse more easily into fibers than soils having a larger one except cholesterol.
(iv) It was confirmed that even a solid soil like carbon black was able to diffuse into polyester film.
(v) It was also confirmed by autoradiographs that the diffusion behavior of carbon black differs from that of fatty soil.
(vi) By comparing the removability of soils in the previous paper¹⁾ with the diffusibility now studied, it is made clear that in general the soils which could easily diffuse into fibers are easily removed by washing.
In conclusion, fatty soils and/or carbon black accumulated on or inside fiber will cause gradual loss of whiteness of polyester fabric.

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