start-ver=1.4
cd-journal=joma
no-vol=55
cd-vols=
no-issue=12
article-no=
start-page=1393
end-page=1398
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2023
dt-pub=20230818
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Effect of the blend ratio of cyclic and linear polyethylene blends on isothermal crystallization in the quiescent state
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=The role of entanglements that form between cyclic and linear polymers in crystallization is of particular interest, but it is not fully understood. We investigated the crystallization behaviors of blends of cyclic polyethylene (C-PE) and linear polyethylene (L-PE) in a quiescent state to elucidate the role of this novel entanglement in crystallization. The samples were prepared by mixing the prepared C-PE and L-PE specimens at L-PE weight fraction (ΦL-PE) values of 0–100 wt%, with the weight average molecular weights of C-PE and L-PE being 175 × 103 and 154 × 103, respectively. The isothermal crystallization behaviors were analyzed through polarizing optical microscopy (POM) and differential scanning calorimetry (DSC). The morphology observed through POM was similar to that of ΦL-PE. From the time evolution of the heat flow measured via DSC, we obtained the half-crystallization time (t1/2) values as functions of ΦL-PE at different degrees of supercooling (ΔT). The 1/t1/2 values of the C-PE and L-PE homopolymers were approximately the same at ΔT = 25.5 and 26.5 K. At a larger ΔT value, the 1/t1/2 value of C-PE was significantly larger than that of L-PE. In contrast, 1/t1/2 reached a minimum value at ΦL-PE = 30–40 wt%, irrespective of ΔT. As the entanglement density increased with increasing ΦL-PE, the crystallization rate was expected to decrease monotonically. By considering the experimental relationship between 1/t1/2 and ΦL-PE, we speculated that the suppression of crystallization in the blended system was caused by a novel entanglement formed by the penetration of the L-PE chain into the C-PE chain.
en-copyright=
kn-copyright=

en-aut-name=KobayashiKeiko
en-aut-sei=Kobayashi
en-aut-mei=Keiko
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=AtarashiHironori
en-aut-sei=Atarashi
en-aut-mei=Hironori
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

en-aut-name=YamazakiShinichi
en-aut-sei=Yamazaki
en-aut-mei=Shinichi
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=

en-aut-name=KimuraKunio
en-aut-sei=Kimura
en-aut-mei=Kunio
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=4
ORCID=

affil-num=1
en-affil=Graduate School of Environmental, Life, Natural Science and Technology, Okayama University
kn-affil=

affil-num=2
en-affil=Graduate School of Environmental, Life, Natural Science and Technology, Okayama University
kn-affil=

affil-num=3
en-affil=Graduate School of Environmental, Life, Natural Science and Technology, Okayama University
kn-affil=

affil-num=4
en-affil=Graduate School of Environmental, Life, Natural Science and Technology, Okayama University
kn-affil=
END

start-ver=1.4
cd-journal=joma
no-vol=11
cd-vols=
no-issue=1
article-no=
start-page=93
end-page=97
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2006
dt-pub=20060315
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=New Attempt at Preparation of Fluorine-containing Poly(ether ketone)s in Supercritical Carbon Dioxide
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=Fluorine-containing poly(ether ketone)s was synthesized by the nucleophilic aromatic substitution reaction of 2,2-bis(4-hydroxyphenyl)-1,1,1,3,3,3-hexafluoropropane and 4,4'-bis(2,3,4,5,6-pentafluorobenzoyl) diphenyl ether in super-critical CO(2). Polymerizations were carried out at 80℃ for 6 hours under 5000 psi of CO(2) pressure, which was super-critical phase. Polymerization concentration was 0.5 g of polymer in 10 - 12 mL of CO(2). The polymer was not obtained in CO(2) due to the insolubility of both the potassium bisphenoxide and the polymer into CO(2). However, the polymer was formed by an addition of DMAc and
NMP in CO(2), even though molecular weight was not so high. Very small amount of co-solvents which were immiscible with CO(2) was effective, and it was 1/20 - 1/25 amount of the solvent used in the conventional poly(ether ketone) synthesis. The polymerization mechanism was also discussed.
en-copyright=
kn-copyright=

en-aut-name=KimuraKunio
en-aut-sei=Kimura
en-aut-mei=Kunio
kn-aut-name=木村邦生
kn-aut-sei=木村
kn-aut-mei=邦生
aut-affil-num=1
ORCID=

en-aut-name=YamazakiShinichi
en-aut-sei=Yamazaki
en-aut-mei=Shinichi
kn-aut-name=山崎慎一
kn-aut-sei=山崎
kn-aut-mei=慎一
aut-affil-num=2
ORCID=

en-aut-name=
en-aut-sei=
en-aut-mei=
kn-aut-name=CassidyPatrick E.
kn-aut-sei=Cassidy
kn-aut-mei=Patrick E.
aut-affil-num=3
ORCID=

en-aut-name=
en-aut-sei=
en-aut-mei=
kn-aut-name=FitchJohn W
kn-aut-sei=Fitch
kn-aut-mei=John W
aut-affil-num=4
ORCID=

en-aut-name=
en-aut-sei=
en-aut-mei=
kn-aut-name=VenumbakaSreenu R.
kn-aut-sei=Venumbaka
kn-aut-mei=Sreenu R.
aut-affil-num=5
ORCID=

affil-num=1
en-affil=
kn-affil=岡山大学

affil-num=2
en-affil=
kn-affil=岡山大学

affil-num=3
en-affil=
kn-affil=Institute for Environmental and Industrial Science, Texas State University at San Marcos

affil-num=4
en-affil=
kn-affil=Institute for Environmental and Industrial Science, Texas State University at San Marcos

affil-num=5
en-affil=
kn-affil=Institute for Environmental and Industrial Science, Texas State University at San Marcos
en-keyword=super-critical carbon dioxide
kn-keyword=super-critical carbon dioxide
en-keyword=plastics
kn-keyword=plastics
en-keyword=high performance
kn-keyword=high performance
en-keyword=environmentally benign
kn-keyword=environmentally benign
END

start-ver=1.4
cd-journal=joma
no-vol=12
cd-vols=
no-issue=1
article-no=
start-page=167
end-page=171
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2007
dt-pub=20070315
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=Efficient Chain Extension Reaction of Poly (butylene terephthalate) by using Crystallization
kn-title=結晶化処理を用いたポリブチレンテレフタレートの効果的鎖延長反応の開発
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=Plastics are quite important materials for not only industrial usages but also our daily life. Many plastics are difficult to reuse because they are susceptible to UV, hydrolysis and so on leading to the reduction of molecular weight. Among them, poly (butylenes terephthalate) (PBT) is a valuable materials prepared by polycondensation reaction, and PBT has the same limitation to reuse. Hence, efficient chain extension reaction for recovered PBT has been needed to improve the properties damaged by chain scission. In this study, new chain extension reaction had been examined by using crystallization as pre-treatment. Isothermal crystallization at 161℃ concentrated the chain end-groups on the surface of the crystals, and chain extension reaction at 210℃, which was lower than the melting temperature of PBT, enhanced the molecular weight significantly compared with the reaction over the melting temperature. It concluded that the pre-treatment of crystallization was favorable for the efficient chain extension reaction and this result provided the new technology for the effective reuse of the plastics.
en-copyright=
kn-copyright=

en-aut-name=IharaSeiji
en-aut-sei=Ihara
en-aut-mei=Seiji
kn-aut-name=井原誠司
kn-aut-sei=井原
kn-aut-mei=誠司
aut-affil-num=1
ORCID=

en-aut-name=ShiromaHisashi
en-aut-sei=Shiroma
en-aut-mei=Hisashi
kn-aut-name=城間弥
kn-aut-sei=城間
kn-aut-mei=弥
aut-affil-num=2
ORCID=

en-aut-name=YamazakiShinichi
en-aut-sei=Yamazaki
en-aut-mei=Shinichi
kn-aut-name=山崎慎一
kn-aut-sei=山崎
kn-aut-mei=慎一
aut-affil-num=3
ORCID=

en-aut-name=KimuraKunio
en-aut-sei=Kimura
en-aut-mei=Kunio
kn-aut-name=木村邦生
kn-aut-sei=木村
kn-aut-mei=邦生
aut-affil-num=4
ORCID=

affil-num=1
en-affil=
kn-affil=岡山大学

affil-num=2
en-affil=
kn-affil=岡山大学

affil-num=3
en-affil=
kn-affil=岡山大学

affil-num=4
en-affil=
kn-affil=岡山大学
en-keyword=Polyester
kn-keyword=Polyester
en-keyword=material recycle
kn-keyword=material recycle
en-keyword=crystallization
kn-keyword=crystallization
en-keyword=chain extension reaction
kn-keyword=chain extension reaction
END

start-ver=1.4
cd-journal=joma
no-vol=12
cd-vols=
no-issue=1
article-no=
start-page=157
end-page=160
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2007
dt-pub=20070315
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=Acceleration of Formation of Shish under Flow by Addition of Irregular Shaped Particles
kn-title=流動場結晶化における異形微粒子添加によるshish構造形成の促進
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=We have shown that the shish was formed from the oriented melt composed of the elongated chains caused by dust particles within the melt via bundle typed nucleation under flow with low shear rate (γ=5s(-1)). This implies that dust particles effectively cause the elongation of chains within the melt. In this work, we observed the crystallization of polypropylene added with irregular shaped particles under shear flow by means of polarizing optical microscope. We prepared various shaped particles such as confetti-like, spherical and rock-like. We found that the size and asymmetric shape of additive particles play an important role for the acceleration of formation of shish.
en-copyright=
kn-copyright=

en-aut-name=YamazakiShinichi
en-aut-sei=Yamazaki
en-aut-mei=Shinichi
kn-aut-name=山崎慎一
kn-aut-sei=山崎
kn-aut-mei=慎一
aut-affil-num=1
ORCID=

en-aut-name=WakabayashiKanji
en-aut-sei=Wakabayashi
en-aut-mei=Kanji
kn-aut-name=若林完爾
kn-aut-sei=若林
kn-aut-mei=完爾
aut-affil-num=2
ORCID=

en-aut-name=MizumaKenta
en-aut-sei=Mizuma
en-aut-mei=Kenta
kn-aut-name=水間健太
kn-aut-sei=水間
kn-aut-mei=健太
aut-affil-num=3
ORCID=

en-aut-name=KimuraKunio
en-aut-sei=Kimura
en-aut-mei=Kunio
kn-aut-name=木村邦生
kn-aut-sei=木村
kn-aut-mei=邦生
aut-affil-num=4
ORCID=

affil-num=1
en-affil=
kn-affil=岡山大学

affil-num=2
en-affil=
kn-affil=岡山大学

affil-num=3
en-affil=
kn-affil=岡山大学

affil-num=4
en-affil=
kn-affil=岡山大学
en-keyword=shish
kn-keyword=shish
en-keyword=crystallization
kn-keyword=crystallization
en-keyword=polypropylene
kn-keyword=polypropylene
en-keyword=shear flow
kn-keyword=shear flow
en-keyword=elongation
kn-keyword=elongation
en-keyword=injection molding
kn-keyword=injection molding
END