Isotactic polypropylene films, which were drawn under necking and afterward annealed at 140°C (named A film) or 157° (named B film) with free ends, were redrawn at angle α=0, 30, 45, 60 and 90° to the first draw direction. The reorientation in these films was studied by measuring the distribution of the refractive indices in the film plane and x-ray diffraction. The main results were as follows.
(1) For A film, the distribution was sharpened and the orientation axis was rotated smoothly toward the redraw direction for any α. But for B film, the distribution became broad till around λ=2, except for α=0° and the orientation axis was rotated slowly toward the redraw direction.
(2) For α=0°, for both films, the crystal orientation was lowered at small draw ratios, while the over all molecular orientation was increased with λ. Therefore the orientation of the amorphous chains may be increased rapidly at first. Particularly, the changes were remarkable for B film.
(3) For α=30, 45 and 60°, both films showed two types of the crystal orientation. For A film, a structure may be produced by the strained tie chains on the process of destruction of the original structure, and this may be oriented readily to the redraw direction, but the transformation do not appear except for A_{60, 3}. While, for B film, the new structure (Type II) having an opposite orientation from the original structure (Type I) appeared manifestly. It seems that the transformation from Type I to Type II structure is followed by the inclination of the lamellae to the film surface and the destruction of the lamellae to the crystal blocks and then, rotation of the crystal blocks about a- or b-axis. These mechanisms may occur concurrently.
(4) For α=90° (only B film), a new structure may be formed and oriented to the redraw direction in a similar manner as above.

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In the short glass fiber-thermosetting resin composites, the interfacial yield shear strength or critical fiber length is one of the dominating factors for the effect of reinforcement. In this paper, the strain rate and the temperature dependence of these factors were studied for the glass fiber-epoxy resin and glass fiber-unsaturated polyester resin composites.
The interfacial yield shear strengths increase in proportion to the logarithm of the strain rate and the slope decreases slightly as the temperature increases. The strain rate and temperature dependences are more remarkable for the composites of which glass fiber surfaces are treated with silane coupling agent than ones of which fiber surfaces are treated with release agent. The strain rate and temperature dependences of interfacial yield shear strength τ_{_??_T} can be related by the following equation.
where _??_ is the strain rate, a_T is the shift factor and subscript T represents the environmental temperature. K₁ and K₂ are corlstants depending on the system of composite, conditions at the fiber-matrix interface and the reference temperature. The strain rate-temperature reduction of mean critical fiber legth (_??__c)_{_??_, T} cam be estimated with (l_c) _{_??_, T}=σ_t d/2τ_{_??_, T}. using τ_{_??_, T} given by the above equation. Here _??__l is the mean strength of links and d is the fiber diameter.

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Photo-induced graft polymerization of methyl methacrylate (MMA) onto aldehyde cellulose was carried out in aqueous systems in either quartz or pyrex reaction tube by irradiation of light with λ>253 nm. The degree of grafting of MMA onto aldehyde cellulose containing a small amount of carbonyl group (15.4 mmol/100g) was greater than that onto cotton cellulose, and the grafting efficiency was 90-100%. The initial rate of grafting R_p onto aldehyde cellulose was found to be expressed as, R_ρ∝[monomer]^1.0×[cellulose]^1.1×[carbonyl]^0.8
The apparent activation energy calculated from the initial rate was 17.1 kcal/mol. The degree of grafting and the apparent number of grafted chains increased and the graft chain length decreased, with increasing the carbonyl content of cellulose. The ratios of the number of radical sites to the carbonyl content was 1: 70. From these results, it was considered that the graft polymerization proceeds under the following reaction scheme.
On irradiation with light of 253 nm wave length, we inferred partial grafting onto the end of chain, which could result from photolytic scission of aldehyde cellulose.

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Optical spatial filtering technique has been applied for detecting defects in textile fabrics. The spatial frequency C of a missing defect is distributed on the low frequency region of the first-order peak C=1, while that of an insertion defect on the high frequency region of the peak. Filtering out the corresponding spatial frequency part makes it possible to distinguish these two defects each other, Furthermore, under favorable conditions, these defects can be graded by suitably filtering out the spatial frequency. A model calculation and two experiments have been made to explore the possibilities.
In actual textile fabrics the disturbances of pick spacings in the neighborhood of a missing defect are approximately given by where k is the pick number from the defect and σi is the standard deviation. Diffraction patterns have been calculated by changing σ_i(1_??_3) and other two parameters, i. e. the ratio of transpatent spacing to pick spacing R (1/6_??_1/2) and the total number of yarns N (40_??_80). The results indicate that the Patterns are mainly distributed over the frequency range of 0.7_??_C_??_0.96. By taking account of the standard deviation _??_ (0.02_??_0.08) representing the inherent irregularity of the pick spacing, it is shown that the frequency ranges 0.7_??_C_??_0.96 and 0.85_??_C_??_0.96 are suitable for detecting the missing defects with σ_i=2 and σ_i=1, respectively. The similar discussions must be applied for an insertion defect.
A model with R=0.25 and N=60 has been constructed with IBM cards, which has missing defects with 1+f(0)=1.2 and insertion defects with 1-f(0)=0.75. The diffraction pattern has been measured by using a pin hole and a photomultiplier tube, which agrees well with the calculated one. Missing defects and insertion defects can easily be distinguished. By choosing the frequency range 1.05_??_C_??_1.2 and 1.25_??_C_??_1.35, the insertion defects with 1-f(0)=0.8 and 1-f(0)=0.75 can also be detected separately. The usefulness of this technique has been demonstrated by detecting a missing defect in a glass textile fabric and an insertion defect in a cotton fabric.

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Styrene-ρ-hydroxystyrene copolymer was acylated with benzoyl chloride, o-methoxybenzoyl chloride, salicylic acid and 3-hydroxy-2-naphthoic acid. The structures of the acylated products have been identified by means of IR and UV spectroscopies.
Methylene Blue in dioxane-ethanol solution containing the above acylated products or polystyrene was exposed to a xenon-arc lamp. The photofading rate of the Methylene Blue was calculated from the changes in the visible absorption spectra. The acylated products having an aromatic ester acted as a retarder on the rate, while polystyrene showed an accelerating action. The retarding action of the acylated products might be explained by the Photo-Fries rearrangement during the photofading of Methylene Blue.

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Surface activity of silk fibroin and four water-soluble proteins was estimated quantitatively using polarography. Maxima which occur on current-voltage curve of reducible substances like oxygen can be suppressed by the addition of surface-active substances. Surface activity of proteins was estimated by the extent of the suppression of the oxygen maximum.
At the interface mercury-water, the proteins were more surface-active in 0.01M-KCl (pH6) than in 0.01M-(CH₃COOH+CH₃COONa) (pH4) and also at 40°C than at 30°C. The extent of the suppression of the oxygen maximum in 0.01M-KCl at 40°C increased in the following order:
egg albumin> serum albumin> hemogrobin> gelatin> silk fibroin

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