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Predecessor
Volume 50, Issue 2
Displaying 1-10 of 10 articles from this issue
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Takeo IIDA, Hirohisa IKEDA, Yoshiko YAMASHITA, Kunio GOTO1993 Volume 50 Issue 2 Pages 65-72
Published: February 25, 1993
Released on J-STAGE: November 22, 2010
JOURNAL FREE ACCESSSynergetic effect of ethylene-vinyl alcohol copolymers (EVOH) with zinc stearate/calcium stearate synergetic soap on the thermal stabilization of poly (vinyl chloride) (PVC) was investigated by colorimetry. Under the present conditions, a marked synergetic effect was observed by compounding EVOH as a solution. But the systems compounding EVOH as a solid did not exhibit any marked effects. In particular, more easily measurable effects were observed with increasing hydroxycontent of EVOH as a solution. The image processing evaluation of the dispersion degree showed that EVOH were finely dispersion into PVC by compounding as a solution, while solid EVOH did not exhibit fine dispersion. These results suggest that the effects of EVOH are markedly dependent on their dispersion degree in PVC compounds. Some values obtained for relationships involving NCG (distance to nearest center of gravity) or area of EVOH particules in the compound PVC and amount of EVOH added were useful parameters to evaluate the dispersion degree of additives in compound plastics.View full abstractDownload PDF (1303K) -
Hogyu YOON, Kiyohisa TAKAHASHI1993 Volume 50 Issue 2 Pages 73-79
Published: February 25, 1993
Released on J-STAGE: November 22, 2010
JOURNAL FREE ACCESSThermal expansion coefficients (CTE) of commingled composites manufactured from commingled yarns composed of carbon fibers (CF) and PEEK [poly (ether-ether-ketone) ] filaments were measured and compared with those of CF/ PEEK prepreg composites. All specimens showed stable and non-scattered CTE data as a result of the thermal treatment or the repeating measurement on the same specimen. This procedure was necessary to obtain reproducible data. The unidirectional (U-D) commingled composite exhibited lower longitudinal CTE than the U-D prepreg composite, and showed a remarkable decrease of CTE at around Tg of PEEK resin. The CTE of the warp direction in 2-dimensional (2-D) commingled composite, that showed lower CTE than the weft direction due to the higher warp density, was found to be almost similar to that of 2-D prepreg (cross-ply) composite. Assuming the temperature dependence of CTE of the carbon fiber itself, theoretical predictions of CTE's of the U-D commingled and the 2-D prepreg composites were obtained in good agreement with experimental results.View full abstractDownload PDF (1267K) -
Takao NOMURA, Takeyoshi NISHIO, Hiroki SATO, Hironari SANO1993 Volume 50 Issue 2 Pages 81-86
Published: February 25, 1993
Released on J-STAGE: November 22, 2010
JOURNAL FREE ACCESSIn order to lighten automobile bumpers and shorten the production cycle, the properties of elastomer-modified polypropylenes were studied. Use of a large amount of reinforced elastomer controlled the growth of micro crystals which formed matrices with amorphous polypropylene, resulting in the increases in crystallinity and fluidity. As a result, high performance elastomer-modified polypropylenes were developed without lowering impact resistance and tensile elongation.View full abstractDownload PDF (1832K) -
Tokao NOMRA, Takeyoshi NISHIO, Hiroki SATO, Hironari SANO1993 Volume 50 Issue 2 Pages 87-91
Published: February 25, 1993
Released on J-STAGE: November 22, 2010
JOURNAL FREE ACCESSIn order to improve the properties of polypropylene (PP) /ethylene propylene rubber (EPR) blends (elastomer modified polypropylene, EMP), which is widely used in the automobile bumpers, we controlled growth of the micro crystals in the elastomer phase and the structure of micro domains by the use of super high crystalline PP. In a super olefine polymer (SOP), considerably higher properties were obtained than those in conventional EMP. The structure characteristics of the SOP were analysed by means of higher resolution electron microscopy, image analysis technique and atomic force microscopy. The structure in the injection molded samples was that the resin and elastomer phases were arranged in strata. In the resin phase, domains of the PP crystalline phase existed in canals of the amorphous and elastomer phase; in the elastomer phase, polyethylene (PE) crystalline lamella domains were in the elastomer matrix. On the micro-structure scale, the SOP had so-called micro composites or molecular composites.View full abstractDownload PDF (2188K) -
Akihiro SUZUKI, Masahiko KONDO, Toshio KUNUGI1993 Volume 50 Issue 2 Pages 93-98
Published: February 25, 1993
Released on J-STAGE: November 22, 2010
JOURNAL FREE ACCESSAnnealing under extremely high tension (HTA) was applied to the high-temperature zone-drawn (HT-ZD) nylon 6 fibers to further improve their mechanical properties. The first and second HTA treatments (HTA-1 and HTA-2) were carried out at 100°C under an applied tension of 532 MPa and at 130°C under 462 MPa, respectively. The purpose of HTA-1 and HTA-2 was to extend fully the amorphous chains unstretched during the HT-ZD. Further, the third HTA treatment (HTA-3) was cariied out at 190°Cunder 271 MPa to crystallize the amorphous chains highly oriented by HTA-1 and HTA-2. The changes in mechanical properties and superstructure with the processing were investigated. The draw ratio and birefringence increased with the processing, and the linear relation existed between both factors. The resulting HTA-3 fiber has a draw ratio of 5.9, a birefringence of 64.5×10-3, and a crystallinity of 49%. The orientation factor of crystallites reached 0.988 by the first HT-ZD, whereas the orientation factor of amorphous regions increased stepwise with the processing. The dynamic modulus (E') increased gradually with the processing. The E' value of the HTA-3 fiber was 21.1 GPa at 25°C and 8.0 GPa even at 180°C.View full abstractDownload PDF (1086K) -
Tsuguo KOBAYASHI, Masatsugu OGATA, Tetsuo ISHIKAWA, Kenji MATSUNOBU1993 Volume 50 Issue 2 Pages 99-106
Published: February 25, 1993
Released on J-STAGE: November 22, 2010
JOURNAL FREE ACCESSThe flame retardant effectiveness of BMC (bulk molding compounds) filled with aluminium trihydrate 0-52wt% applied to the stator housing of a single-phase induction motor (80W) was investigated. The following results were obtained. (1) The motor housing composed of BMC filled with 30wt% of A1 (OH) 3 evolved a smaller amount of inflammable gases during the motor lock test than that made of unfilled BMC. (2) During the motor lock test, the motor housing composed of BMC filled with 30wt% of Al (OH) 3 produced threetimes more water than that of unfilled BMC. The surface temperature of the housing made of BMC filled with Al (OH) 3 was lower than that made of unfilled BMC by about 40°C (3) The motor housing composed of BMC filled with 30wt% of A1 (OH) 3 evolved smaller amounts of inflammable gases than that of unfilled BMC by factors of about 1/5-1/40.View full abstractDownload PDF (1414K) -
Akihiro SUZUKI, Hiroyuki KONDO, Toshio KUNUGI1993 Volume 50 Issue 2 Pages 107-113
Published: February 25, 1993
Released on J-STAGE: November 22, 2010
JOURNAL FREE ACCESSNylon 6 fibers were hot-drawn at two drawing temperatures (Td) : 170°C and 190°C. The hot-drawing at each Td was carried out at two drawing speeds (Vd) : 10 mm/min and 100 mm/min. Thus the nylon 6 fibers were hot-drawn under four conditions. The draw ratio (λ) and birefringence of the fiber obtained at Td=170°C and Vd=10mm/min have the maximum values of 5.6 and 64.5×10-3, respectively. The crystallinity of the fibers hot-drawn at Vd=10 mm/min min increased linearly with increasing λ, while that of the fibers at Vd=100mm/min was held almost constant values aboveλ=3.5. Although the crystallite sizes of the fibers hot-drawn at Vd=10mm/min increased with an increase in λ, those of fibers obtained at Vd=100 mm/min decreased. The melting peaks of the fibers obtained at Vd=10mm/min became sharp with increasing λ, however, those of fiber at Vd=100 mm/min broadened above λ=3.5. Young's moduli of the fibers under the four conditions increased linearly with increasing λ; the values are closely related to an orientation factor of amorphous regions.View full abstractDownload PDF (1107K) -
Tatsuo IWASAKI, Kousuke TOMITA, Yoshitsugu UEDA1993 Volume 50 Issue 2 Pages 115-120
Published: February 25, 1993
Released on J-STAGE: November 22, 2010
JOURNAL FREE ACCESSAfter oxidation of a nylon 6 fiber or film by ozone, vinyl monomers, such as acrylamide, methyl methacrylate, and vinyl acetate, were graft polymerized onto the nylon 6. The effects of the ozone-oxidation time and polymerization time on the apparent percent graft and the percent yield of the grafts were investigated. The molecular weight of nylon 6 decreased slightly by ozone-oxidation. In the case of the acrylamide graft polymerization system, pre-treatment of γ-irradiation in the air or in vacuum before ozone oxidation gave a higher percent graft. In the case of methyl methacrylate, the apparent percent graft did not increase with increasing ozone-oxidation time. But, the apparent percent graft of vinyl acetate increased with increasing ozone-oxidation time.View full abstractDownload PDF (986K) -
Yoshikazu GOTOH1993 Volume 50 Issue 2 Pages 121-126
Published: February 25, 1993
Released on J-STAGE: November 22, 2010
JOURNAL FREE ACCESSAnalysis of terminal unsaturation (TU) in propoxylation confirmed that increases in the concentrations of propylene oxide and catalyzer caused no increase in the TU value. The activation energy of the formation of terminal unsaturated bonds was 27.6 kcal/mol, whereas that of propoxylation was 16.1 kcal/mol. The TU value increased exponentially with reaction temperature.View full abstractDownload PDF (796K) -
Graft Polymerization of Silicone Macromer onto Chlorinated Polyethylene Having Acrylic Acid PendantsYoshiyuki IKEDA, Kozo MISUMI1993 Volume 50 Issue 2 Pages 127-130
Published: February 25, 1993
Released on J-STAGE: November 22, 2010
JOURNAL FREE ACCESSChlorinated polyethylene having acrylic acid units as pendants (CPE-AA, degree of substitution=3.9) were prepared by the reaction of chlorinated polyethylene (CPE) with acrylic acid using 1, 8-diazabicyclo [5. 4. 0] -7-undecene. Graft polymerization of silicone macromer (McDMS4, MW=423, McDMS10, MW=1000) onto CPE-AA was carried out by using azobisisobutyronitrile as the initiator. The degree of grafting and the graft efficiency in graft polymerization of McDMS onto CPE-AA decreased with increasing molecular weight of McDMS. Graft polymerization of McDMS onto CPE without acrylic acid residues hardly occurred.View full abstractDownload PDF (525K)
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