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81.
Tadatomi Nishikubo Atsushi Kameyama Tomoko Yaguchi 《Journal of polymer science. Part A, Polymer chemistry》2000,38(21):4006-4012
Poly(cyanurate)s (P‐1–P‐4) containing triazine groups in the main chain and pendant chloromethyl groups in the side chain were synthesized by the polyaddition of bis(epoxide)s with 2,4‐dichloro‐6‐(diphenylamino)‐s‐triazine (DPAT) using quaternary onium salts as catalysts. The polyaddition of diglycidyl ether of bisphenol‐A (DGEBA) with DPAT proceeded smoothly in chlorobenzene at 100 °C for 12 h to give P‐1 with Mn = 19,000 in a 92% yield, when tetrabutylammonium chloride (TBAC) was used as a catalyst. However, no reaction occurred without a catalyst or with triethylamine alone under the same reaction conditions. Polyadditions of other bis(epoxide)s with DPTA also proceeded smoothly using 5 mol % of TBAC as a catalyst in chlorobenzene to produce corresponding polymers (P‐2≈P‐4) in high yields under similar reaction conditions. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 4006–4012, 2000 相似文献
82.
Tadatomi Nishikubo Atsushi Kameyama Chie Saito 《Journal of polymer science. Part A, Polymer chemistry》2000,38(19):3604-3611
Poly(ether)s (P‐1–P‐4) containing triazine groups in the main chain and pendant phenoxy groups in the side chain were synthesized by the polyaddition of bis(epoxide)s with 2,4‐di‐(p‐chlorophenoxy)‐6‐(diphenylamino)‐s‐triazine (DCTA) with quaternary onium salts or crown ether complexes as catalysts. The polyaddition of diglycidyl ether of bisphenol A with DCTA proceeded smoothly in chlorobenzene at 120 °C for 24 h to give P‐1 with a number‐average molecular weight of 24,800 in a 95% yield when tetraphenylphosphonium chloride (TPPC) was used as a catalyst; however, no reaction occurred without a catalyst under the same reaction conditions. Polyadditions of other bis(epoxide)s with DCTA also proceeded smoothly with 5 mol % TPPC as a catalyst in chlorobenzene to produce the corresponding polymers (P‐2–P‐4) in high yields under similar reaction conditions. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 3604–3611, 2000 相似文献
83.
Tadatomi Nishikubo Atsushi Kameyama Muneharu Ito Akira Suzuki 《Journal of polymer science. Part A, Polymer chemistry》1998,36(16):2873-2880
Addition reaction of (3-methyl-3-oxetanyl)methyl acetate (MOMA) with bis(4-mercaptophenyl) sulfide (BMPS) was examined in certain organic solvents. When the reaction of MOMA with BMPS was performed without any catalyst in hexamethylphosphoric triamide (HMPA) and N-methyl-2-pyrrolidone (NMP) at 130°C for 24 h, conversions of the corresponding adduct were 96 and 36%, respectively, which was confirmed by 1H-NMR spectra. On the other hand, when the reaction was carried out using tetraphenylphosphonium bromide (TPPB) as a catalyst under the same conditions, conversions of the adduct were 96 and 81% in HMPA and NMP, respectively. This result shows that although the addition reaction of oxetane compound with aromatic dithiol proceeds without any catalyst in HMPA, the reaction was strongly enhanced by adding TPPB in NMP. On the basis of the above results, polyadditions of bis((3-methyl-3-oxetanyl)methyl) terephthalate (BMOT) and bis((3-ethyl-3-oxetanyl)methyl) terephthalate with BMPS were performed using TPPB as the catalyst in NMP at 130°C for 24 h. As a result, the corresponding high molecular weight polymers 1 (Mn = 22,400) and 2 (Mn = 12,800) with pendant primary hydroxyl groups were obtained in 83 and 89% yields without any gel products, respectively. Furthermore, a low molecular weight oligomer was obtained from the polyaddition of BMOT with aliphatic dithiol, bis(mercaptomethyl)benzene, under the same reaction conditions. The catalytic activity on the polyaddition of BMOT with BMPS was also examined, and it was found that thermally stable TPPB and crown ether complexes at the reaction temperature (130°C) have higher catalytic activity than tetrabutylammonium bromide and tetrabutylphosphonium bromide to produce polymer 1 with high molecular weight. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2873–2880, 1998 相似文献
84.
Hiroto Kudo Toshiki Ohshiro Hiroyuki Atsumi Ayako Kamio Tadatomi Nishikubo Saeko Murakami 《Journal of polymer science. Part A, Polymer chemistry》2012,50(3):458-465
A new synthetic strategy for polymers containing amino acids in the main chain was developed. Monomers N‐oxetanylalanine (N‐Oxe‐Ala‐COOH), N‐oxetanylglutamic acid (N‐Oxe‐Glu‐COOH), and N‐oxetanyllysine (N‐Oxe‐Lys‐COOH) containing both oxetanyl and carboxyl groups were synthesized, and self‐polyaddition and self‐copolyaddition of these monomers afforded the corresponding polymers containing amino acids in the main chain [poly(OxAla), poly(OxLys), poly(OxGlu), poly(OxAla‐co‐OxGlu), poly(OxGlu‐co‐OxLys), and poly(OxAla‐co‐OxLys)] with molecular weight in the range of 920–6620, in satisfactory yields. The physical properties, such as solubility, glass transition temperature, and thermal stability, were consistent with the amount of carboxyl groups at the chain ends. Biodegradability of the polymers was examined by the biochemical oxygen demand method; the decomposition ratios of poly(OxAla) and poly(OxAla‐co‐OxGlu) were about 60%, whereas that of poly(OxGlu) was nearly 100% after 28 days. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
85.
Hiroto Kudo Tomohiko Kurakata Masaki Sasaki Tadatomi Nishikubo 《Journal of polymer science. Part A, Polymer chemistry》2004,42(6):1528-1536
The polyaddition of bis(oxetane)s 1,4‐bis[(3‐ethyl‐3‐oxetanylmethoxymethyl)]benzene (BEOB), 4,4′‐bis[(3‐ethyl‐3‐oxetanyl)methoxy]benzene (4,4′‐BEOBP), 1,4‐bis[(3‐ethy‐3‐oxetanyl)methoxy] ‐benzene (1,4‐BEOMB), 1,2‐bis[(3‐ethyl‐3‐oxetanyl)methoxy]benzene (1,2‐BEOMB), 4,4‐bis[(3‐ethyl‐3‐oxetanyl)methoxy]biphenyl (4,4′‐BEOMB), 3,3′,5,5′‐tetramethyl‐[4,4′‐bis(3‐ethyl‐3‐oxetanyl)methoxy]biphenyl (TM‐BEOBP) with active diesters di‐s‐phenylthioterephthalate (PTTP), di‐s‐phenylthioisoterephthalate (PTIP), 4,4′‐di(p‐nitrophenyl)terephthalate (NPTP), 4,4′‐di(p‐nitrophenyl)isoterephthalate (NPIP) were carried out in the presence of tetraphenylphosphonium chloride (TPPC) as a catalyst in NMP for 24 h, affording corresponding polyesters with Mn's in the range 2200–18,200 in 41–98% yields. The obtained polymers would soluble in common organic solvents and had high thermal stabilities. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1528–1536, 2004 相似文献
86.
Hiroto Kudo Yusuke Fujiwara Makoto Miyasaka Tadatomi Nishikubo 《Journal of polymer science. Part A, Polymer chemistry》2010,48(24):5746-5751
Polycarbosilanes were synthesized by hydrosilylation reaction of A2 monomer containing bis Si? H moieties and Bn (n = 2, 3, and 4) monomers containing di‐, tri‐, and tetra‐vinyl groups in the presence of Karstedt's catalyst. The corresponding linear polycarbosilanes (LPC) and hyperbranched polycarbosilanes (HBPC) having Mn 2200–51,500 were obtained in 34–94% yield, without any gel product. The values of refractive index (nD) of the synthesized LPC and HBPC were in the range from 1.460 to 1.711, and were consistent with the structures of the synthesized products. In the case of HBPC, the values of nD increased with increase of number‐average molecular weight (Mn), molecular weight distribution (Mw/Mn), and glass transition temperature (Tg), apparently because of increased density due to the presence of microgels, that is, high refractive index hyperbranched carbosilanes could be synthesized by A2 + Bn (n = 3 and 4) method. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
87.
Synthesis and photochemical properties of poly(ester–amide)s containing norbornadiene (NBD) residues
Akihiko Ikeda Akinori Tsubata Atsushi Kameyama Tadatomi Nishikubo 《Journal of polymer science. Part A, Polymer chemistry》1999,37(7):917-926
N,N′‐Bis[(3‐carboxynorbornadien‐2‐yl)carbonyl]‐N,N′‐diphenylethylenediamine (BNPE) was synthesized in 70% yield by the reaction of 2,5‐norbornadiene‐2,3‐dicarboxylic acid anhydride with N,N′‐diphenylethylenediamine. Other dicarboxylic acid derivatives containing norbornadiene (NBD) residues having N,N′‐disubstituted amide groups were also prepared by the reaction of 2,5‐NBD‐2,3‐dicarboxylic acid anhydride with certain secondary diamines. When the polyaddition of BNPE with bisphenol A diglycidyl ether (BPGE) was carried out using tetrabutylammonium bromide as a catalyst in N‐methyl‐2‐pyrrolidone at 100°C for 12 h, a polymer with number average molecular weight of 69,800 was obtained in 98% yield. Polyadditions of other NBD dicarboxylic acid derivatives containing N,N′‐disubstituted amide groups with BPGE were also performed under the same conditions. The reaction proceeded very smoothly to give the corresponding NBD poly(ester–amide)s in good yields. Photochemical reactions of the obtained polymers with N,N′‐disubstituted amide groups on the NBD residue were examined, and it was found that these polymers were effectively sensitized by adding appropriate photosensitizers such as 4‐(N,N‐dimethylamino)benzophenone and 4,4′‐bis(N,N‐diethylamino)benzophenone in the film state. The stored energies in the quadricyclane groups of the polymers were also evaluated to be about 94 kJ/mol by DSC measurement of the irradiated polymer films. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 917–926, 1999 相似文献
88.
Tadatomi Nishikubo Atsushi Kameyama Kousuke Tsutsui Masami Iyo 《Journal of polymer science. Part A, Polymer chemistry》1999,37(12):1805-1814
New photoreactive p-methylcalix[6]arene (MCA) derivatives containing cationically polymerizable groups such as propargyl ether (calixarene 1), allyl ether (calixarene 2), and ethoxy vinyl ether (calixarene 3) groups were synthesized with 80, 74, and 84% yields by the substitution reaction of MCA with propargyl bromide, allyl bromide, and 2-chloroethyl vinyl ether (CEVE), respectively, in the presence of either potassium hydroxide or sodium hydride by using tetrabutylammonium bromide (TBAB) as a phase transfer catalyst (PTC). The p-tert-butylcalix[8]arene (BCA) derivative containing ethoxy vinyl ether groups (calixarene 4) was also synthesized in 83% yield by the substitution reaction of BCA with CEVE by using sodium hydride as a base and TBAB as a PTC. The MCA derivative containing 1-propenyl ether groups (calixarene 5) was synthesized in 80% yield by the isomerization of calixarene 2, which contained allyl ether groups, by using potassium tert-buthoxide as a catalyst. The photochemical reactions of carixarene 1, 3, 4, 5, and 6 were examined with certain photoacid generators in the film state. In this reaction system, calixarene 3 containing ethoxy vinyl ether groups showed the highest photochemical reactivity when bis-[4-(diphenylsulfonio)phenyl]sulfide bis(hexafluorophosphate) (DPSP) was used as the catalyst. On the other hand, calixarene 1 containing propargyl ether groups had the highest photochemical reactivity when 4-morpholino-2,5-dibuthoxybenzenediazonium hexafluorophosphate (MDBZ) was used as the catalyst. It was also found that the prepared carixarene derivatives containing cationically polymerizable groups such as propargyl, allyl, vinyl, and also 1-propenyl ethers have good thermal stability. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1805–1814, 1999 相似文献
89.
Tadatomi Nishikubo Atsushi Kameyama Muneharu Ito Tomoe Nakajima Haruo Miyazaki 《Journal of polymer science. Part A, Polymer chemistry》1999,37(15):2781-2790
The polyaddition of 1,4-bis[(3-ethyl-3-oxetanyl)methoxymethyl]benzene (BEOB) with 3,3′,5,5′-tetrachlorobisphenol A (TCBPA) was examined with or without catalysts. High molecular weight polymer (polymers 1) (Mn = 13,600) with pendant primary hydroxyl groups was obtained in a 99% yield without any gel products when the reaction was performed with 5 mol % of tetraphenylphosphonium bromide as a catalyst in NMP at 160°C for 96 h. However, when the reaction was carried out without a catalyst under the same conditions, a low molecular weight polymer (Mn = 3200) was obtained in a 51% yield. The structure of the resulting polymer was confirmed by IR, 1H-NMR, and 13C-NMR spectra. In this reaction system, it was also found that tetraphenylphosphonium iodide and crown ether complexes such as 18-crown-6 (18-C-6)/KBr and 18-C-6/KI have high catalytic activity. Polyadditions of 1,4-bis[(3-methyl-3-oxetanyl)methoxymethyl]benzene with TCBPA and BEOB with 3,3′,5,5′-tetrabromobisphenol-S were also examined, and corresponding polymers (polymers 2 and 3) were obtained in good yields. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2781–2790, 1999 相似文献
90.