The present investigation was carried out to study the effect of type of polyethers as soft segments upon the physical and fiber properties of polyether-polyester block copolymers obtained by polycondensation. For this purpose, B-PBG block copolymers composed of poly (oxy-1, 4-butylene) glycol (PBG) as a soft segment and-1, 2-polyethylene-1, 2-diphenoxyethane-p, p′-dicarboxylate (B) as a hard segment were prepared and their physical and fiber properties were compared mostly with those of B-PEG block copolymers. The results are summarized as follows: (1) Though the rates of ester-interchange reaction of polyethers with dimethylester (BM) as a polyester component were in the decreasing order of PBG>PEG>PPG, no marked difference was observed in their intrinsic viscosity nubers between resulting B-PBG and B-PEG copolymers. The degrees of polymerization of B-PBG and B-PEG were relatively high, whereas that of B-PPG was low. (2) As for the degree of crystallinity and melting point B-PBG surpassed B-PEG, and this difference increased with the longer polyether chain. This fact might be attributed to the change of compatibilities of polyether chain with polyester chain in the block copolymers. (3) The difference of compatibility affected the state of amorphous region in the block copolymers. Accordingly B-PBG with low compatibility showed lower softening temperature than B-PEG. (4) The mechanical properties of the fibers were influenced by their crystallinity. The fiber from B-PBG 1000 had higher tensile strength and Young's modulus, but lower elasticity and elongation than B-PEG 1540 fiber. (5) T-PBG 1000 using polyethylene-terephthalate (T) as a polyester component had lower melting point, tensile strength and Young's modulus than B-PBG 1000. From the above experimental results, it was found that the physical and fiber properties of polyether-polyester block copolymers were influenced remarkably by the compatibilities between their hard and soft segments.
Graft copolymerization of acrylamide onto microcrystalline cellulose “Avicel” was carried out using ceric salt as an initiator. It was found that the total conversion and the grafting ratio increase with increasing concentration of acrylamide, but they decrease with the increase in ceric salt concentration. The rates of both the total conversion and the grafting ratio decreased with the reaction time. The rate of consumption of ceric ion in the reaction with “Avicel” was much faster than with linter pulp and α-methyl-D-glucoside. It is supposed to be attributed to the fact that its molecular weight is low and it contains more end groups. It was also supposed that the graft copolymerization is initiated preferentially at the reducing end groups rather than hydroxyl groups in cellulose. Remarkable difference in reactivity was observed irrespective of the grain size of the sample cellulose. Namely, the reactivity was independent of the apparent surface area of the cellulose grain. Therfore, it was concluded that the reaction occurs in the inside of the cellulose grains, but the results of X-ray diffraction measurement indicated that the graft copolymerization does not occur in the crystalline region of cellulose.
A radius of crimp is very important properties of self-crimpable fibers. R. H. Brand1) already has reported on the its equation. However the application of this equation to actual fiber is restricted to a special case, because it involves several assumptions. In this report a general equation is derived: under only one assumption that any component of fiber obeys Hooke's law as follows. E: young's modulus, S: shrinkage, ∫c ( ) dA shows area integration. From eq. (1) following equation is get about two component conjugate fiber. Eq. (2) is applicable to bicomponent fibers having any type of cross section, that is circular, rectangular and sheath core. The followings are made clear: (1) Evaluation becomes possible about the radius of self-crimpable fiber which has continuously distributed value of shrinkage and Young's modulus, for example, asymmetrically quenched fiber. (2) Brand's eq. is a special case of our equation when cross section is rectangular, S1, S2_??_1 and p=1. (3) Radius of crimp becomes smaller in the following cases: 1) when the Young's modulus of inside component is lower, 2) when absolute value of shrinkage is larger (the difference of shrinkage makes the radius of crimp smaller) and 3) when the degree of eccentricity is larger in sheath-core fiber. (4) When radius of curvature of boundary line formed by two component, composing circular cross-sectional conjugate fiber, becomes larger, the radius of crimp gets smaller and saturates to the value about three times of radius of fiber. (5) From the application to rubber model coil, a good agreement can be obtained between the calculated values and observed values about radius of crimp.
The adsorbability of dyestuffs at the oil-water interface, and the influence of inorganic electrolytes on it, were investigated by measuring electrocapillary curves. The oil phase was the solution of a surface inactive organic electrolyte in methylisobutylketone, and the aqueous phase contained various dyestuffs in addition to the inorganic electrolyte. It was found that the interfacial tension decreased over the anodic or cathodic polarization range, depending upon whether the dyestuff was anionic or cationic. In addition, this decrease was strongly influenced by the kind and concentration of the electrolyte in the aqueous phase. For the same kind of dyestuffs, the surface activity increased by decreasing “Inorganic-Organic Balance”, proposed by Fujita, and a linear relation held between the decrease in interfacial tension and this “Balance”, with the slope -3.5. A linear relation held between the net interfacial excess concentration of dyestuff and the cubic root of the dyestuff concentration in the aqueous phase, which was in good agreement with Davies' deduction. This adsorbability of dye at the oil-water interface was found to correspond to the amount of dye actually absorbed by 6 Nylon fibres.
The adsorption of metal cations on domestic and eri silk spun yarns treated with salts of transition metals such as Mn, Fe, Co, Ni and Zn and their effect on the photodegradation of the silk yarns was investigated. When the silk yarns were treated with an aqueous solutions of Mn-, Fe-, Co-, Ni- or Zn-salt, the adsorbed amount of Mn2+, Co2+, Ni2+ and Zn2+ ions was larger in the case of eri silk than that of domestic silk but the adsorbed amount of Fe3+ ions was larger in domestic silk. The adsorbed amount of each metal cations increased with the increase of pH by the addition of NH4OH in the metal salt solutions. The relations between the adsorbed amount of metal cations and treating time can be classified into three types according to the extent of metal hydroxide formation by the adding of NH4OH. Some metal salts showed maximum adsorption of cations at a specific concentration. As for other metal salts, the adsorbed amount of cations increased with the incaease of the metal salt concentrations, and the adsorbed amount of cations continued to increase until their adsorption were saturated. This different phenomena are related to the extent of pH decrease due to the increase in melal salt concentration. The adsorption of Mn2+ and Ni2+ ions in the treated silk yarns showed only slight inhibive effect on their photodegradation when the deterioration was tested by the fade meter irradiation. On the contrary, Fe3+ and Zn2+ ions adsorbed in the treated silk yarns accelerated their deterioration.
Chloromethylation of 3-(4′-dimethylaminophenylazo)-benzenesulfonic acid and dyeing character of the product were investigated. The results obtained were summarized as follows: The optimum condition of chloromethylation of the dye was found when the reaction was carried out in acetic acid solution at 40_??_50°C, using gaseous hydrogen chloride and paraformaldehyde as chloromethylation agent and phophoric acid as a catalyst. The above reaction resulted in the degree of chloromethylation of 36_??_39% after 24hrs. Paperchromatography of the three components, unchloromethylated dye, chlromethylated dye and its hydrolysis product, showed that they were most successfully separated by using a mixture (CH3)2CO, H2O, C4H9OH, (1:2:4) as developing agent. As a part of colours fixed on wool could not be extracted even with organic solvents, it is estimated that the dye is covalently bonded with wool.