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Volume 46, Issue 4
Displaying 1-14 of 14 articles from this issue
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Toshinobu HIGASHIMURA, Mitsuo SAWAMOTO1989 Volume 46 Issue 4 Pages 189-201
Published: April 25, 1989
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSThis article is a concise review on the principles (design of initiators and reaction conditions) of living cationic polymerization of vinyl monomers and on the controlled synthesis of a variety of new polymers thereby. Living cationic polymerization has been shown to occur by stabilizing the propagating species (carbocations) with (i) counteranions or (ii) added weak bases, both of which hold a suitably strong nucleophilic interaction with them. Judicious choice of initiators and reaction conditions has permitted the synthesis of living polymers from vinyl ethers (VE) and styrene derivatives. Living cationic polymerizations of VEs with functional pendant groups have led to the synthesis of a variety of (i) pendant-functionalized monodisperse polymers, (ii) end-functionalized polymers with terminal COOH, NH2, etc., (iii) macromonomers, and (iv) amphiphilic block polymers. A method has been developed for determination of the concentration of the growing end, which has in turn permitted to measure the lifetime of the living polymers and to confirm their livingness.View full abstractDownload PDF (2264K) -
Eiichi KOBAYASHI, Yasuhiro ISHIZUKA, Yasunori KOUCHAKU, Junji FURUKAWA1989 Volume 46 Issue 4 Pages 203-208
Published: April 25, 1989
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSAddition polymerization of 2, 5-thiophenedithiol to 2, 5-diethynylthiophene was studied in toluene solution at 60°C under UV irradiation. The addition polymerization proceeded easily to yield a dark-yellowish novel polymer. The polymer was insoluble in conventional organic solvents. The electroconductivities of undoped polymers and I2-doped polymers were 10-14S/cm and 10-5S/cm, respectively. In the IR spectrum, the vinylene groups showed absorptions at 1355 cm-1 (cis) and 925 cm-1 (trans). The microstructure of polymers was determined to be 85% cis and 15% trans based on cis and trans adducts of 2-thiophenethiol to 2-ethynylthiophene. By the MINDO/3 method, the value of ΔH≠ of the intermediate radical for the cis isomer was 5.4 kcal/mol lower than that of the intermediate radical for the trans isomer. However, the value of ΔH of the trans isomer is 0.2 kcal/mol lower than that of the cis isomer. The stability of the intermediate radicals is primarily responsible for the microstructure of resulting polymers.View full abstractDownload PDF (1018K) -
Yuichi NAKAGAWA, Yasuhiko YOSHIDA, Tadataka YAMASHITA, Junji FURUKAWA1989 Volume 46 Issue 4 Pages 209-213
Published: April 25, 1989
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSThe plasma polymerized thin films, obtained from the mixture gas of butadiene and O2, were analyzed by FT-IR and XPS. Carbonyl and carboxyl groups contents in the films increased as the ratio of O2 in the mixture gas increased. The wettability of the thin films to water was enhanced by an increase in the carboxyl groups. Coating of the plasma polymerized thin films on polymer materials were found to be effective for the enhancement of hydrophilic property of polymer materials.View full abstractDownload PDF (790K) -
Yoshiharu DOI, Naoko TOKUHIRO, Kazuo SOGA1989 Volume 46 Issue 4 Pages 215-222
Published: April 25, 1989
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSA soluble V (acac) 3-Al (C2H5) 2Cl catalyst was active for the polymerization of 1, 4-pentadiene, 1, 5-hexadiene, 1, 6-heptadiene, or 1, 7-octadiene to give polymers in toluene at -78°C. The polydispersities (Mw/Mn) of poly (1, 5-hexadiene) and poly (1, 7-octadiene) were as narrow as 1.4. The chain microstructures of produced polymers were characterized by analysis of the 1H and 13C NMR spectra. A portion of monomeric units in poly (diolefin) s was saturated as a result of cycloaddition. The cyclization of monomeric units in the propagating process decreased in the following order: poly (1, 6-heptadiene) (100%) >poly (1, 4-pentadiene) (60%) >poly (1, 5-hexadiene) (50%) >poly (1, 7-octadiene) (0%). The chain propagation mechanisms of poly (1, 6-heptadiene) and poly (1, 7-octadiene) were proposed.View full abstractDownload PDF (932K) -
Masako YOSHIKUNI, Koji OOWAKU, Yasuta KOIKE, Kuniharu KOJIMA1989 Volume 46 Issue 4 Pages 223-231
Published: April 25, 1989
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSTributylborane (Bu3B) known as low-temperature radical initiator is unstable in air. To cope with this demerit, a series of dibutylborinic acid alkyl and aryl esters were prepared by the reaction of Bu3B and alcohols or phenols, and the polymerization of vinyl compounds by these esters was examined. Some dibutylborinates were found to be more efficient initiators of the polymerization of vinyl monomers than Bu3B which shows dead-end polymerization behavior, although the initial rate of radical generation by borinates was lower. The behavior of polymerization by dibutylborinates was similar to that by Bu3B. Good correlations were found to exist between the rates of polymerization by dibutylborinic acid alkyl esters and the rates of oxygen absorption, but were not found in the polymerization by aryl esters.View full abstractDownload PDF (1336K) -
Yasuo YUKI, Hideo KUNISADA, Shuji KONDO1989 Volume 46 Issue 4 Pages 233-239
Published: April 25, 1989
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSNew aromatic diamines containing a polymerizable isopropenyl group, e. g., 2, 4-bis (p-aminoanilino) -6-isopropenyl-1, 3, 5-triazine [1] and 2- (p-aminoanilino) -4- (m-aminoanilino) -6-isopropenyl-1, 3, 5-triazine [2], were prepared by the reduction of corresponding dinitro-compounds [3] and [4]. The homopolymerization and the copolymerization of these monomers with styrene (M1) were carried out in dimethyl sulfoxide using azobisisobutyronitrile as an initiator. The copolymerization parameters (r1, r2, Q, and e) were determined. New aromatic poly (amido-guanamine) s were synthesized by solution polycondensation from [1] and [2] with terephthaloyl chloride or isophthaloyl chloride. The thermal decomposition temperatures of these poly (amido-guanamine) s by the TGA method are about 370°C.View full abstractDownload PDF (970K) -
Masataka KUBO, Hideki YAMASHITA, Shouji IWATSUKI1989 Volume 46 Issue 4 Pages 241-244
Published: April 25, 1989
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSThree heterophanes were studied in vapor deposition polymerization. Thiophenophane gave poly (2, 5-thienylene-ethylene) as a tough film. Furanophane gave monomeric state of 2, 5-dimethylene-2, 5-dihydrofuran. Furanothiophenophane was found to give a tough film of poly (2, 5-thienylene-ethylene) and monomeric 2, 5-dimethylene-2, 5-dihydrofuran separately.View full abstractDownload PDF (565K) -
Jun YANO, Yoko HIGUCHI, Takaaki TANAKA1989 Volume 46 Issue 4 Pages 245-251
Published: April 25, 1989
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSThe electropolymerization of aniline derivatives was carried out by three different electrolytic modes, in order to elucidate the mechanism of the polymer growth on an electrode substrate. From the results obtained, the following mechanism was suggested. In the initial stage, the monomers were polymerized by a radical-chain mechanism, until a small amount of the seed polymer was formed on the electrode substrate. However, the polymer growth on the electrode substrate took place by not only the radical-chain mechanism but also the incorporation-oxidation mechanism of the seed polymer.View full abstractDownload PDF (1410K) -
Structural Control of Polymer End-Groups by Dithiocarbamate InifertersTakayuki OTSU, Yukiya KOBAYASHI, Akira KURIYAMA1989 Volume 46 Issue 4 Pages 253-259
Published: April 25, 1989
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSThe photopolymerization of styrene (St) and methyl methacrylate (MMA) with N, N′-diethyl and N, N′-dimethyldithiocarbamate (1b and 1c), benzyl N-ethyldithiocarbamate (2b) and p-xylylene bis (N-ethyldithiocarbamate) (3b) as iniferters was carried out in bulk at 30°C. The yield and molecular weight (M) of the polymers in the photopolymerization of St and MMA with these iniferters were found to increase with increasing reaction time, indicating that these polymerizations proceeded via a living radical mechanism proposed previously, and 2b and 3b served as approximately mono-and di-functional photoiniferters, respectively. The block copolymerization with the polymeric photoiniferters obtained by 2b (also 1b and 1c) and 3b was found to give AB and ABA block copolymers, respectively.View full abstractDownload PDF (1135K) -
Kiyokazu IMAI, Tomoo SHIOMI, Yasuyuki TEZUKA, Noriyuki FUJIOKA, Takao ...1989 Volume 46 Issue 4 Pages 261-267
Published: April 25, 1989
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSThe stereoregularity of poly (vinyl alcohol) (PVA) samples obtained through the radical polymerization of various substituted aromatic vinyl esters was studied by means of 13C NMR spectroscopy. The structures of PVAs obtained through vinyl benzoate derivatives, which can hold the coplanarity between phenyl and carbonyl groups, were found to iso-rich rather than fully atactic structure. Activation enthalpies were found to be favorable for meso propagation in the polymerization of halogen substituted vinyl benzoate derivatives. In the polymerization at low temperatures (0-10°C), it was found that the isotacticity of PVA polymerized under the UV-sensitized conditions was lower than that obtained with a common radical initiator.View full abstractDownload PDF (1121K) -
Kenji HANABUSA, Yumi KAMOGAWA, Akio KUROSE, Hirofusa SHIRAI, Yoshiyuki ...1989 Volume 46 Issue 4 Pages 269-272
Published: April 25, 1989
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSThe polymerization of γ-benzyl L-glutamate N-carboxy anhydride (BLG-NCA) was examined in a magnetic field. The polymerization rate increased in dichloromethane or dibromomethane in a magnetic field of 3600 G. The molecular weight of poly (γ-benzyl L-glutamate) (PBLG) obtained with application of the magnetic field was higher than that of PBLG obtained without it. Pseudo first-order rate constants (k) for polymerization were determined at different temperatures. Arrhenius plots of ln k versus 1/T indicate that there is no difference in activation energy between the polymerizations with and without application of the magnetic field. Therefore, the application of magnetic field is considered to influence the term of activation entropy in activation free energy for polymerization. The rate acceleration may be explained by the suitable alignment of BLG-NCA monomers and/or growing PBLG chains by the magnetic field.View full abstractDownload PDF (624K) -
Nobuyuki HIGASHI, Minoru TAKEMATSU, Masazo NIWA, Hirofusa SHIRAI1989 Volume 46 Issue 4 Pages 273-276
Published: April 25, 1989
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSA novel two-dimensional photopolymerization at a highly oriented bilayer surface was studied. A new polymerizable amphiphile containing styrene sulfornate as a counter ion and photoinitiators consisting of two long alkyl chains and a xanthate group, which were coupled through the spacer with different chain lengths, were prepared. Photoinitiators were incorporated into the polymerizable matrix without affecting the membrane physical state. The formation of ultra-high polymer upon UV irradiation in a bilayer state was controllable by the spacer length of the initiators.View full abstractDownload PDF (667K) -
Hiroshi HAMANA, Tomoyoshi KATO, Tokio HAGIWARA, Tadashi NARITA1989 Volume 46 Issue 4 Pages 277-279
Published: April 25, 1989
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSIsoprene oligomerization catalyzed by lithiated diethylenetriamine in the presence of diethylenetriamine was studied in toluene. The reaction product showed a unimodal GPC peak at MGPC=500 (polystyrene standard). According to the 1H NMR and GC-MS analysis, the reaction product was 1: 4 adduct of diethylenetriamine and isoprene formed by 1, 4-addition: 2, 14-dimethy1-5, 8-bis (3-methyl-2-butenyl) -5, 8, 11-triaza-2, 13-pentadecadiene (A) or 2, 14-dimethy1-5, 11-bis- (3-methyl-2-butenyl) -5, 8, 11-triaza-2, 13-pentadecadiene (B).View full abstractDownload PDF (411K) -
Yoshiharu KIMURA, Kenji SHIROTANI, Hideki YAMANE, Toshio KITAO1989 Volume 46 Issue 4 Pages 281-284
Published: April 25, 1989
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESS3- (R, S) - [ (Benzyloxycarbonyl) methyl] -1, 4-dioxane-2, 5-dione, a six-membered cyclic diester comprising both the D, L-malic acid and glycolic acid units, was prepared and polymerized in bulk and in solution with tin octylate as the catalyst. As in the polymerization of L-isomer, poly (β-benzyl malate-co-glycolic acid) with a molecular weight of ca. 8000 was obtained in high yield. Its 1H and 13C NMR spectra revealed that the polymer sequence of M and G was random. The polymer was subjected to hydrogenolysis in the presence of palladium charcoal to deprotect the pendant benzyl groups quantitatively. Finally, poly (α-D, L-malic acid-co-glycolic acid), having carboxyl pendants, was obtained in high yield.View full abstractDownload PDF (685K)
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