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1. Evaluation of Degree of Branching for Hyperbranched Poly(aryl ether ketone)s prepared by A2 + BB’2 Approach | |||
Li Xiujie,Zhang Shuling,Lei Lei,Jiang Zhenhua | |||
Chemistry 28 May 2010 | |||
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Abstract:A fast and highly efficient approach to hyperbranched poly (aryl ether ketone)s (HPAEKs) via the polycondensation of A2 and BB’2 monomers has been described. Commercially available hydroquinone (A2 monomer, HQ) and effortlessly synthesized 2,4’,6-trifluoro-benzophenone (BB’2 monomer, TF) were thermally polycondensed to prepared fluoro or phenolic-terminated hyperbranched poly(aryl ether ketone)s with K2CO3 and Na2CO3 as the catalysts. Analyses of FTIR and 1H-NMR spectra revealed the structures of the resultant polymers. The degrees of branching (DBs) of the fluoro-terminated hyperbranched polymers were determined to be 50-57 % by 1H-NMR spectra, whereas the degrees of branching (DBs) of the phenolic-terminated hyperbranched polymers were determined to be 100 %. | |||
TO cite this article:Li Xiujie,Zhang Shuling,Lei Lei, et al. Evaluation of Degree of Branching for Hyperbranched Poly(aryl ether ketone)s prepared by A2 + BB’2 Approach[OL].[28 May 2010] http://en.paper.edu.cn/en_releasepaper/content/4374267 |
2. Determination of A New Mode of Reaction for Hyperbranched Poly(aryl ether ketone)s | |||
LI Xiujie,ZHANG Shuling,LEI Lei,JIANG Zhenhua | |||
Chemistry 28 May 2010 | |||
Show/Hide Abstract | Cite this paper︱Full-text: PDF (0 B) | |||
Abstract: A fast and highly efficient approach to hyperbranched poly (aryl ether ketone)s (HPAEKs) via the polycondensation of A2 and BB’2 monomers has been described. Commercially available hydroquinone (A2 monomer, HQ) and effortlessly synthesized 2,4’,6-trifluoro-benzophenone (BB’2 monomer, TF) were thermally polycondensed to prepared fluoro terminated hyperbranched poly(aryl ether ketone) with K2CO3 and Na2CO3 as the catalysts. During the reaction, p-carbonyl group fluorine of TF reacts rapidly with phenolic group of HQ, forming dominant dimers and some other species. The dimer can be considered as a new AB’2 monomer. Further reactions among molecules AB’2 and AB’2 with some other species result in the formation of hyperbranched poly (aryl ether ketone), as proven by mass spectra (MS). | |||
TO cite this article:LI Xiujie,ZHANG Shuling,LEI Lei, et al. Determination of A New Mode of Reaction for Hyperbranched Poly(aryl ether ketone)s[OL].[28 May 2010] http://en.paper.edu.cn/en_releasepaper/content/4374264 |
3. Preparation of Hyperbranched Poly(aryl ether ketone)s via A2 + BB\'2 Approach | |||
LI Xiujie,ZHANG Shuling,LEI Lei,JIANG Zhenhua | |||
Chemistry 28 May 2010 | |||
Show/Hide Abstract | Cite this paper︱Full-text: PDF (0 B) | |||
Abstract:A fast and highly efficient approach to hyperbranched poly (aryl ether ketone)s (HPAEKs) via the polycondensation of A2 and BB’2 monomers has been described. Commercially available hydroquinone (A2 monomer, HQ) and effortlessly synthesized 2,4’,6-trifluoro-benzophenone (BB’2 monomer, TF) were thermally polycondensed to prepared fluoro or phenolic-terminated hyperbranched poly(aryl ether ketone)s with K2CO3 and Na2CO3 as the catalysts. Analyses of FTIR and 1H-NMR spectra revealed the structures of the resultant polymers. These hyperbranched polymers exhibit excellent solubility in generally organic solvents and possess moderate molecular weights with broad distributions determined by gel permeation chromatograms (GPC). | |||
TO cite this article:LI Xiujie,ZHANG Shuling,LEI Lei, et al. Preparation of Hyperbranched Poly(aryl ether ketone)s via A2 + BB\'2 Approach[OL].[28 May 2010] http://en.paper.edu.cn/en_releasepaper/content/4374219 |
4. Conventional and RAFT Radical Copolymerization of beta-Pinene and Acrylonitrile | |||
An-Long Li,Hui Liang,Jiang Lu | |||
Chemistry 24 January 2007 | |||
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Abstract:The feasibility of radical copolymerization of beta-pinene and acrylonitrile was clarified for the first time. The monomer reactivity ratios evaluated by Fineman-Ross method were r(Pin) = 0, r(AN) = 0.66 in dichloroethane at 60˚C with AIBN. The reactivity ratio data show that the copolymerization was a “simple alternating copolymerization”, yielding polymers rich in acrylonitrile units and randomly alternated by single beta-pinene unit. Furthermore, the possible controlled copolymerization of beta-pinene and acrylonitrile was then attempted via the reversible addition-fragmentation transfer (RAFT) technique. At a low beta-pinene/acrylonitrile feed ratio of 10/90 or 25/75, the copolymerization by using CPDB as the transfer agent displayed the typical features of “living” polymerization, such as first-order kinetics, a linear increase of the Mn with monomer conversions and low polydispersities (< 1.3). However, the “living” character could be observed only within certain overall monomer conversions. At higher overall conversions, the copolymerizations deviated from the living behavior probably due to the competitive degradative chain transfer of beta-pinene. | |||
TO cite this article:An-Long Li,Hui Liang,Jiang Lu. Conventional and RAFT Radical Copolymerization of beta-Pinene and Acrylonitrile[OL].[24 January 2007] http://en.paper.edu.cn/en_releasepaper/content/10873 |
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