The general equation of the melting point (T_m, ) depression for the binary copolymers with various block lengths was presented. By using this equation, the relationships between the T_m and the copolymer composition were discussed for the methoxymethylated nylon-6 and the ethylene/propylene (E/P) copolymers. It was shown that the longer the mean length of block sequence, the higher the T_m.

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Measurements of air drag on spinning filaments at take-up speeds of up to 6, 000 m/min are reported. Air drag on filaments can be expressed as a function of the diameter-based Reynolds number: K value lies in the region of 0.23-0.49 for filaments spun into still air and 0.77 for filaments spun into axisymmetric air stream. K value strongly depends on the filament vibration and on the filament spacing in the spinline.
Air drag (σ_air) and inertia (σ_in) contributions to the spinning stress are predominant in high speed melt spinning and hence, the spinning stress (σ_L) can be simply expressed as From this simple equation, air drag coefficients (namely n and K in the form of ) can be determined by conventional means and the solidification distance from the spinneret can be roughly estimated.

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Adsorption behavior of organic compounds on poly (4-vinylpyridine) (P-4-VP) was studied by the inverse gas chromatography at temperatures encompassing the glass transition point (T_g) of the polymer.
Using P-4-VP as a stationary phase in the GC column, retention data were obtained for a series of polar organic probes (good solvents): n-propanol, n-butanol, n-amylalcohol and n-hexanol, and a nonpolar hydrocarbon (nonsolvent): n-dodecane.
At temperatures well above T_g, the specific retention volume (V_g) increased linearly with increasing peak area (S), whereas at temperatures below T_g, two distinct regions in the V_g and S relation were observed. At the low probe concentrations, V_g increased with decreasing S markedly in a curvilinear fashion, while at the high concentrations, V_g increased with increasing S linearly. In the low concentration region, plots of 1/V_g against √S for all systems were represented by straight lines. The limiting specific retention volumes (V⁰_g ) were estimated in both regions by extrapolating the respective relations to S=0.
Values of In V⁰_g were plotted against the reciprocal of thermodynamic temperature. Each plot showed a Z shaped curve characteristic of the system in which a thermal transition occurred in the temperature region concerned. From the plots, T_g of P-4-VP was estimated as 126°C.
Heats of adsorption at the infinite dilution of the solute in the stationary phase were determined from the temperature dependence of V_g. Values of 19-21 and 13-15kcal/mol were obtained, respectively, at the low and high concentrations.
In the present system, plot of log V⁰_g vs. boiling point was represented not by a straight line, which is observed generally for systems of n-alcohol and polymer, but by a curve with a minimum. This may indicate that n-alcohols of the lower boiling point have the stronger affinity for P-4-VP.
From these results, it is considered that adsorption of the probe on the surface of the stationary phase dominated at temperatures below T_g and that penetration of the probe into the bulk occurred at temperatures above T_g.

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Polyacrylonitrile (PAN) film turned brown by UV-light irradiation. IR spectra showed that the double bonds, such as C=C, C=O and C=N, were formed similarly to the thermal reactions. Observations of UV spectral changes and IR dichroism, however, showed that the chemical structures of photoproducts were different from those of the thermal products. Increase in molecular orientation enhanced the formation of carbonyl groups in both thermal and photoreaction. This effect was observed more markedly in the latter.

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Heat transfer printing was examined on polyester/cotton (E/C) blends modified by graft copolymerization of various vinyl monomers initiated with Ce^>IV> ion.
The graft copolymerization of vinyl monomers except for acrylamide (AAm) and acrylonitrile (AN) onto E/C blend was found to increase K/S value of the fabrics heat-transfer printed with Teraprint Blue R (C. I. Disperse Blue 14) in the following order: vinyl acetate (VAc)> n-butyl meth-acrylate (n-BuMA)≈methyl methacrylate (MMA)>2-ethylhexyl acrylate (2-EtHA)>n-butyl acrylate (n-BuA)>methyl acrylate (MeA)>ethyl acrylate (EtA)≈styrene, However, the graft copolymerization of AAm and AN did not increase the K/S value of the heat transfer printed fabrics.
Tear strength of the 12.1%-MMA grafted E/C broad retained 72% in warp and 87% in weft of those of the untreated fabric. Tensile strength of the broad retained 92% in warp and 103% in weft. With increasing percent grafting, the moisture regain of the grafted E/C broad decreased for the all monomers except for AAm, while it increased for AAm, The graft copolymerization of vinyl monomers increased the flexual rigidity of the grafted E/C broad in the following order: n-BuMA>MeA>VAc>MMA>2-EtHA>EtA>n-BuA. The handle of the n-BuA-, EtA- and 2-EtHA-grafted E/C broad was soft and sticky, while the handle of the MMA-n-BuA (74.8 mole% in comonomer)-grafted E/C broad was soft and not sticky.
The fabrics heat transfer printed onto the MMA-n-BuA-grafted E/C broad with 14 dyes showed a satisfied color fastness to dry heating, light, perspiration, rubbing and washing.

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In the process of manufacturing yarn, we very often rotate yarn package, and the electric power needed for that is considerably large. In Ishikawa prefecture, the consumption of the electric power by the twister has been investigated for the purpose of saving energy. Although the investigation was carried out as a whole of twisting system, it is important to analyze each factor in order to improve the efficiency in saving energy. We took notice of the power which a rotating yarn package loses in stirring the air around it, and to obtain its quantity, we investigated the relationship between the coefficient of friction loss C_f and the Reynolds number Re. For the estimation of Re, the radius of the cylinder was taken as the significant liner dimension. The following results were obtained.
(1) In case of a smooth cylinder, C_f=375/Re and C_f=0.049Re_-1/5 were obtained where Re is below 0.6×10⁵ and above 0.9×10⁵, respectively.
(2) In case of a cylinder on which a cotton yarn is wound, its C_f is equal to the value for the smooth cylinder when Re=0.2×10⁵, and is proportional to Re-1/5
(3) When the package is covered, C_f is reduced. Especially, a remarkable reduction in C_f occurs for a package with rough surface.

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The polystyrene films containing 1, 4-diaminoanthraquinone dye were examined with an optical microscope during heating and cooling at constant rates. Spherulitic structures were observed which were composed of needle-like crystallites of the dye in the cooling process. Size of these spherulites increased with increasing dye content and with decreasing cooling rate. Size of crystallites formed in cooling process was larger than that formed in heating process.

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