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Predecessor
Volume 39, Issue 1
Displaying 1-8 of 8 articles from this issue
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Takeyoshi WATANABE1982 Volume 39 Issue 1 Pages 1-6
Published: January 25, 1982
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSWeathering properties were studied for fiberglass reinforced plastic (FRP) under flexural load. FRP specimens under stresses of 0, 15 and 30% load of flexural strength, were exposed to outdoor sun light. Reference samples were stored in indoor dark place. For such samples, the relation between the progress of degradation and the viscoelastic behavior of FRP and the chemorheological and physical fractions in total stress relaxation were studied. The results of flexural tests and relaxation test were evaluated by a five element Maxwell model. In the first 6 months, a parallelism was found between the chemical behavior such as cross linking of unsaturated polyester resin and the physical behavior such as stress relaxation. This was followed by the degradation of FRP as indicated by the decrease of the strength.View full abstractDownload PDF (1260K) -
Takeyoshi WATANABE, Masaaki YASUDA1982 Volume 39 Issue 1 Pages 7-13
Published: January 25, 1982
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSCreep behaviors were studied for unsaturated polyester resins (UP) under flexural load, at temperatures near the heat distortion temperature (HDT). The results were analysed by the use of a four element Voigt-Kelvin model which consists of elastic, viscoelastic and viscous contributions;
The effect of temperature on E1 and E2 of UP was monotonically decreased with the cross linking density. Arrhenius plots of τ2 and η2 for four UP samples gave parallel straight lines, but those of η3 did not. Creep strains of UP samples were approximately in agreement with the prediction of of the above equation, but a UP sample with low cross linking density indicated viscous behavior owing to the plastic deformation in third term. The values of n in Nutting's equation were monotonically increased with temperature. n values were 0-0.2 at temperatures lower than HDT, so that the third term could be neglected. n values were 0.4-0.5 at higher temperatures than HDT, so that plastic deformation owing to viscous contribution were considerably increased.View full abstractDownload PDF (1123K) -
Takeyoshi WATANABE1982 Volume 39 Issue 1 Pages 15-21
Published: January 25, 1982
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSCreep behaviors were studied for an unsaturated polyester resin (UP) and the fiberglass reinforced plastics (FRP), at a temperature near the heat distortion temperature (HDT) (71°C) of the UP. The results were analysed by the use of four element Voigt-Kelvin model,
The generallized theory for cross-linked polymers were applicable for moduli and viscosities of the model's elements for UP and FRP. From the relation between the chemical structure of UP and creep behavior of FRP, it was found that the elastic behavior of FRP were kept at temperatures higher than HDT. The values of n of Nutting's equation for FRP were 0.02-0.08, being unchanged by the raise of temperature. But, n for UP were monotonically increased; n=0.04-0.14 at 23°C, 0.24-0.33 at 40-60°C and 0.40-0.43 at 80-100°C.View full abstractDownload PDF (1191K) -
Sumio YAMADA, Takeo HAMAYA1982 Volume 39 Issue 1 Pages 23-27
Published: January 25, 1982
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSThe efrect of radiation does on the permeation characteristics of γ-irradiated polyethylene membrane to benzene and benzene-aniline mixture has been investigated by a pervaporation technique. The liquid permeation rate of benzene and benzene-aniline mixture remained unchanged up to the radiation does of 50 Mrad, and a marked decrease was observed in the liquid permeation of benzene through the membrane irradiated with a dosage higher than 50 Mrad. Similarly the separation factor showed no obvious change in the range of 0-50 Mrad dosage. In order to elucidate the correlation between radiation dose and liquid permeation behavior, swelling ratio, the concentration of net work chains, and gel fraction were cited.
As a method of initiating the pervaporation experiment, it can be considered that there are two modes of operation procedures having a difference in which of the equilliration of membrane with solvent feed or evacuation is firstly conducted. It was found that these methods cause a great difference in the liquid permeation rates of benzene and benzene-aniline mixture although affected little on the separation factor.View full abstractDownload PDF (1201K) -
Tatsuaki YAMAGUCHI, Makoto YAMAMOTO, Yoshifusa SHIMADA1982 Volume 39 Issue 1 Pages 29-34
Published: January 25, 1982
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSMore than 90 wt% of di-2-ethylhexylphthalate (DOP), which remained intact in waste agricultural soft poly (vinyl chloride) (PVC) after one year's usage (about 35 wt% of the original value), was recovered by dissolution-reprecipitation method with N, N-dimethylformamide and methanol. A mixed solvent of methanol and methyl ethyl ketone (60/40vol%) was also effective for the rapid extraction of DOP at a low temperature. The recovered PVC was reformed to crosslinked polymer by pentaerythritol tetrakis (mercaptopropionate) in the presence of benzoyl peroxide. The thermal stability of the reformed PVC was better than that of virgin PVC, whereas the tensile strength value almost identical.View full abstractDownload PDF (1048K) -
Yasuhiko IKKAKU, Toshio KADOWAKI, Masayoshi OKUBO, Tsunetaka MATSUMOTO1982 Volume 39 Issue 1 Pages 35-39
Published: January 25, 1982
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSFor the purpose of clarifying some fundamental problems concerning the emulsion-type pressure sensitive adhesives containing emulsifier, the effects of emulsifier on the tack of poly (butyl acrylate) (PBA), important as a base polymer for the pressure sensitive adhesives, were investigated.
The emulsion film, in thickness of ca. 0.05 mm, was formed on glass substrate after adding each nonionic emulsifier of nonylphenol/ethylene oxide/adduct to PBA emulsion prepared by emulsifier-free emulsion polymerization. The tack at both the substrate- and the air-side interfaces of this film was measured.
The tack was affected by the kind and concentration of emulsifier, film clarifying time, and standing time of the film. Such results are reasonably explained from the view point of the localization of emulsifier at the interfaces of the film.View full abstractDownload PDF (958K) -
Yoshinori MIYAMOTO, Takakazu KOJIMA, Yoshinobu HOSAKA1982 Volume 39 Issue 1 Pages 41-47
Published: January 25, 1982
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSSixteen isomeric benzamide (BA) oligomers containing three, four, five, and six benzene rings in the main chain were synthesized, and the dependence of their thermal stabilities on the structures was investigated by thermogravimetry and differential scanning calorimetry. The melting points of BA oligomers were lower than those of phenylenephthalamide (PPA) oligomers, and the fusion enthalpy and entropy of BA oligomers were higher than those of PPA oligomers. The melting points of BA oligomers increased with an increase in number of benzene rings in a similar way as the case of PPA oligomers. The fusion enthalpy and entropy of BA oligomers containing odd-numbered benzene rings were lower than those containing even-numbered benzene rings. These results were attributed mainly to the symmetry of molecular structure for BA oligomers.View full abstractDownload PDF (1126K) -
Poly (ethylene-vinyl acetate) and Poly- (ethylene-vinyl alcohol)Sumio YAMADA, Tsutomu NAKAGAWA, Takeo HAMAYA1982 Volume 39 Issue 1 Pages 49-52
Published: January 25, 1982
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSIn order to obtain knowledge of modifying barrier properties of polyethylene films to gases and water vapor by copolymerization technique, we studied the effect of sequence structure of repeating units on the permeation behavior of hydrogen, helium, carbon dioxide, oxygen, argon, methane, ethane, nitrogen and water vapor in vinylacetate grafted polyethylene, vinylalcohol grafted polyethylene, ethylene-vinylacetate random copolymer and ethylene-vinylalcohol random copolymer. Effect of introducing the less permeable structural unit, vinylacetate, on barrier properties of copolymers to gases was greater in graft form than in random form. On the other hand, the effect due to introducing vinyl alcohol unit was greater in random form than in graft form. The permeability of vinyl acetate random copolymer to water vapor was higher than that calculated assuming simple additivity for the permeabilities of each component, and water vapor permeability of the graft copolymer was lower than the calculated value.View full abstractDownload PDF (871K)
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