The shrinkage behavior has been investigated for rapidly heated nylon 6 fibers treated by benzyl alcohol or methoxymethylated to different extents. The treatment effects on the relative shrinkage and the shrinkage rate of the dry and wet samples were clarified. No necking type shrinkage was observed for the fiber regardless of the treatment. The shrinkage behaviors on rapid heating were well reproduced by the modified Jacobs et al.'s equation with n=2,
where S_t and S_∞ are the relative shrinkages at t (time)=t and ∞, respectively, k the rate constant, and n the index number. According to the rate processes theory, the free energy of activation for the shrinkage rate was evaluated for each sample, together with the enthalpy and entropy of the activation.

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Measurements of the diameter and temperature of the fibrous materials running from spinneret toward a winding machine during the melt spinning of polystyrene were carried out with the similar technique employed in our previous report. The decrease in diameter of the running material along the spinning line was discussed comparing the relative magnitude of the two components of loss compliance of the material, J″_η based on viscous flow and J″_i based on recoverable viscoelastic deformation. Both J's were obtained from flow data and the viscosity and viscoelastic data appeared in literatures.
As a result, the diameter of the running material decreased rapidly in the initial high temperature zone where J″_η>J″_i and the decrease became unobservable in the zone where J″_η<J″_i
The changes in diameter and temperature of the running material were analyzed numerically using equations of force and heat balance. Because one material parameter, extensional viscosity, was used in the force balance equation, the agreements of the observed and computed values were limited to those in the high temperature zone where flow was dominant in the deformation.

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Several fibrous filter tips for cigarette smoke have been examined to establish the relation between the filter efficiencies and filter properties: kinds of fiber, fiber denier per filament, cross section of fiber, volume fraction of fiber, weight fraction of fibers and filter making methods.
Filtration efficiency ΔE for the tips is given as
where k: filtration coefficient, ε_f: filter porosity, L: filter length, d_fm: modified diameter of fiber, n: exponent.
For total particulate matter (TPM) filtration efficiency, k and n are determined as 8.4×10^-4 and 1.22, respectively. k value for nicotine in cigarette smoke depends on the kinds of fiber in the filter tip.
From the viewpoint of the low resistance - high efficiency, effective filtration is achieved by longer filter length, finer denier per filament, non-circular cross section of fiber and greater affinity between fiber and cigarette smoke.

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The initial adsorption behaviors of Cu(II), Ni (II), Co (II) and Mn (II) on silk fibroin fiber were investigated in terms of the adsorption rate and the diffusion of metal cations into the fiber. The following results were obtained:
1) Two adsorption stages were recognized as the initial fast and the later slow one. The initial fast adsorption continued until the adsorbed amounts of metal cations became about 60% of the equilibrium adsorption for Cu (II) and about 75_??_80% for the other metal cations. The initial adsorption rates were 4-27 times higher than those of the later step at pH 5.0, 25°C.
2) The apparent activation energies of the initial adsorption were obtained as 5.6_??_13.9 kcal/mol, and the order was Mn (II)_??_Co (II)>Ni (II)>Cu(II).
3) On the assumption that the silk fibroin fiber is a cylinder, the apparent diffusion coefficients of Ni (II), Co (II) and Mn (II) which calculated by applying Hill's equation of diffusion were increased with increasing the metal cation concentration in solution. But the effect of the concentration in solution on the apparent diffusion coefficient was smaller for Cu (II) than for the other metal cations.

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A kinetic model has been proposed to interpret the fading behavior of 1, 2-bis (benzoxazolyl) ethylene, a disperse dye type fluorescent brightening agent, on polymer film.
Rate laws are derived on two assumptions that the fading reaction proceeds competitively through isomerization and dimerization reactions and that population of the dye in a hole in the film can be described by Poisson distribution. When one dye molecule is captured in a hole, only the isomerization occurs. On the other hand, when two or more molecules are captured in a hole, the dyes fade through isomerization and/or dimerization reactions.
The derived rate laws are solved numerically by assuming the values of kinetic parameters and the number of holes (θ) in the polymer film. Comparison of the theoretical results with the observations suggests that, at high dyeing temperature, the number of holes in the film has to be small, and accordingly the apparent rate of dimerization is large.
Characteristic fading curves and other experimental results are reasonably understood by the kinetic model.

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2-Dimethylamino-4, 6-bis (methylamino)-s-triazine (I) was prepared by displacing two chlorine atoms of cyanuric chloride with methylamino groups and then the remaining one with dimethylamino group.
A new melamine derivative containing two methylol groups, i. e. 2-dimethylamino-4, 6-bis (N-methyl-N-hydroxymethylamino)-s-triazine (II), was prepared by treating I with aqueous solution of formaldehyde.
A new compound, 2-dimethylamino-4, 6-bis (N-methyl-N-methoxymethylamino)-s-triazine (III), was also prepared by etherification of the methylol groups of II.
I, II, and III were identified with elemental analysis, infrared spectra, and NMR spectra.
The polycondensation reaction of II in the presence of zinc nitrate as catalyst was followed with intermittent measurements of free formaldehyde and N-methylol contents.
The formaldehyde contents of methylene ether (N-CH₂OCH₂-N) and methylene (N-CH₂-N) linkages in the polycondensates of II were determined separately from difference of acid hydrolysis rates of these linkages.

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The degradation of p-aminoazobenzene (p-AAB) by the crude fractions of an enzyme complex [Lebedev solution] was examined by spectroscopy and thin layer chromatography. The inner dialysis solution degraded p-AAB, but did so more slowly than the Lebedev solution. The precipitate resulting from salting out with 60% saturated ammonium sulfate degraded p-AAB. However, this degradation depended upon whether the precipitate was desalted or not. The supernatant liquid of the heated Lebedev solution was further dialysed. The inner dialysis solution, which contained heat-resistant protein with a molecular weight of 25, 000, was found to degrade p-AAB. Addition of the outer dialysis solution to either the inner dialysis solution or the salted out fraction enhanced the degree of degradation of p-AAB, although to lesser extents than the Lebedev solution. These results showed that the enzyme complex as a whole contributes more effectively to the degradation of p-AAB than each of the crude fractions.

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