Dehydrochlorinated poly(vinyl chloride) (PVC) was obtained by heating PVC powder itself and a PVC solution in N, N-dimethyl formamide (DMF). The emissivity is investigated principally from the following view points: the extent of dehydrochlorination; the color and shape change of the treated samples. The amount of polyene structure increases in the treated samples and the sample shape changes to granules with the progress of dehydrochlorination. The emissivity of the two different heated samples measured as a function of extent of dehydrochlorination did not agree well. The effects are resulted from the even or uneven dehydrochlorination in the samples. Although the weight of original PVC decreases from 8.00mg to 4.15 or 3.48mg per unit area with the dehydrochlorination according to the two kinds of heating processes, their emissivities increase slightly. The increased emissivities perhaps are caused to form the porous surface of the emitters with increasing amount of polyene structure.

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The strain recovery elasticity caused by the rapid removal of m₂ from the load (m₁+m₂) on a fiber was studied for the nylon-6 fibers in water. The initial velocity _??_₁ at t(time)=0 of strain recovery is given by where C₁ is the spring constant, m₁ is the constant load on a fiber, m₂ is the removal load on a fiber and G is the gravitational acceleration. The value of C₁ obtained is about 2.66×10⁷dyne/cm at a light load of m₁ (_??_0.03g/d) and about 3.6×10⁶dyne/cm at a load m₁ over 0.19g/d, respectively. The former is almost equal to that of the nylon-6 crystal and the latter is in the range of C₁ (3.35×10⁶_??_6.21×10⁶dyne/cm) of the high tenacity yarns of nylon-6.

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Poly (ethylene terephthalate) (PET) fibers containing poly (oxyethylene) (PEO) were prepared to study the molecular weight effect of PEO upon antistatic property. A series of fibers containing 2wt% of PEO with molecular weight M_n=4, 000 (PEO (4)), 20, 000 (PEO (20)), and 100, 000 (PEO (100)) as well as the fiber containing 10wt% of PEO (20) were spun by a melt spinning at 270°-280°C, and then submitted to 4.9-fold drawing and heat-treated at 170°C. Each fiber was washed in a boiling water for 1hr.
Observation of the transversal sections of the unwashed fibers by light (LM) and scanning electron microscopes (SEM) showed that PEO particles are distributed in the PET matrix. The particle size of PEO in the as-spun fibers increased markedly with increasing the M_n, and its size and number decreased after drawing. The antistatic property of the drawn fibers evaluated by half-lifetime of leakage of static charge was improved with the increase in PEO's M_n. Therefore, this tendency is to be explained in connection with its particle size. The particle size in the sample containing 10wt% PEO (20) was the same as that in the sample containing 2wt% PEO (20), though the number was much larger than that of the latter sample. For the both fibers, the antistatic properties before washing were in the same level.
The LM and SEM photographs of the washed fibers indicated that PEO particles bled out from the interior of fiber, with the fibers' inner structure being porous. This observation is correlated with the deterioration of antistatic property after washing. The rate of bleed-out of PEO (20), however, was somewhat slower than that of other PEOs, i.e., the PEO (20) particles still remained on the fiber surface after washing. This may explain the fact that the antistatic property of the fiber containing PEO (20) was unchanged or improved after washing.
The viscoelastic nature of those blend fibers was also examined. It showed that the compatibility of PEO with PET decreased with the molecular weight increase of PEO. A tendency to deterioration of mechanical properties of the blend fiber is consistent with this incompatibility. It can be concluded from these findings that blending about 2wt% PEO (20) is the most effective as far as homopolymer of PEO is used for antistatic modification of polyester.

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Chemically modified amino acids in the silk and wool fibers treated with epichlorohydrin (E), glycidol (G) and glycidyl methacrylate (GMA), were identified by gas chromatography-mass spectrometry as their N(O)-trifluoroacetyl n-butyl ester derivatives. O-(Dihydroxypropyl)-and O-(chlorohydroxypropyl)tyrosines, and N^ε-(dihydroxypropyl)-and N^ε, N^ε-bis(dihydroxypropyl)lysines were identified in all silk and wool samples, indicating that OH and Cl groups of the epoxide-amino acid adducts were labile during acid hydrolysis of the samples. N^ε, N^ε-Bis (chlorohydroxypropyl) lysine and O-[(dihydroxypropoxy)hydroxypropyl] tyrosine were also identified in the silk and wool fibers treated with G, the latter being formed by addition of a second molecule of G to O-(dihydroxypropyl) tyrosine residue. S-(Dihydroxypropyl)-and S-(2-carboxypropyl) cysteines were identified by the single ion monitoring (SIM) method for the wool fibers treated with GMA, indicating that thiol groups of cysteine residues could react with both epoxy and methacryl groups of GMA. S-(Chlorohydroxypropyl) cysteine as well as S-(dihydroxypropyl) cysteine were found in the other wool samples by the SIM method. N^ε-(Chlorohydroxypropyl)- and N^ε, N^ε-bis (chlorohydroxypropyl) ly sines were also found in the wool fibers treated with E by the SIM method.

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The rate of hydrolysis of aromatic polyester-ether homologs in an aqueous caustic soda solution was investigated at temperatures of 60°C to 90°C, and the activation energy for the reaction was determined. The results indicate that the polyester-ether homologs have higher alkali resistances than poly(ethylene terephthalate). The activation energy for hydrolysis of poly (ethylene 1, 2-diphenoxyethane-p, p′-dicarboxylate) [B type polyester-ether] was estimated as high as 22.6kcal/mole.

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In order to prepare a model for an artificial joint with a hydrogel structure similar to articular cartilage and to examine its frictional behavior, poly(vinyl alcohol) (PVA) dissolved in water was grafted by γ-ray irradiation onto preirradiated high density polyethylene (HDPE). The friction experiment was carried out in a ball-on-disk friction machine. The friction coefficient in water decreased from 0.04 (for HDPE) to 0.02 by the PVA grafting, indicating that the hydrogel structure is effective to the reduction of friction coefficient in water. The unworn and worn surfaces of the PVA-grafted HDPE were also examined by electron microscopy.

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