Abstract:The tadpole-shaped copolymers polystyrene(PS)-b-[cyclic poly(ethylene oxide)(PEO)] [PS-b-(c-PEO)] contained linear tail chains of PS and cyclic head chains of PEO were synthesized by combination of glaser coupling with living anionic polymerization (LAP) and ring-opening polymerization (ROP). Firstly, the functionalized polystyrene-glycerol (PS-Gly) with two active hydroxyl groups at ω end was synthesized by LAP of St and the subsequent capping with 1-ethoxyethyl glycidyl ether (EEGE) and then deprotection of protected hydroxyl group in acid condition. Then, using PS-Gly as macro-initiator, the ROP of EO was carried out using diphenylmethylpotassium(DPMK) as co-catalyst for AB2 star-shaped copolymers PS-b-(PEO-OH)2, and the alkyne group was introduced onto PEO arm end for PS-b-(PEO-Alkyne)2. Finally, The intramolecular cyclization was carried out by glaser coupling reaction in pyridine /Cu(I)Br /N,N,N',N'',N''-pentamethyldiethylenetri-amine (PMDETA) system under room temperature, and tadpole-shaped PS-b-(c-PEO) with high efficiency (almost 100%) was formed. The target copolymers and their intermediates were well characterized by SEC, 1H NMR and FT-IR in details. The critical micelle concentration (CMC) and the thermal properties were also determined and compared to investigate the influence of architecture on properties. The results showed that tadpole-shaped copolymers had higher CMC values and lower Tm, Tc, Xc than that of their precursors of star-shaped copolymers.

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	1. Synthesis of Amphiphilic Tadpole-shaped PS-b-(c-PEO) Copolymers by the Combination of Glaser Coupling with Living Anionic Polymerization and Ring-opening Polymerization
	WANG Guowei,HU Bin,FAN Xiaoshan,ZHANG Yannan,HUANG Junlian*
	Chemistry 23 May 2011
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	Abstract:The tadpole-shaped copolymers polystyrene(PS)-b-[cyclic poly(ethylene oxide)(PEO)] [PS-b-(c-PEO)] contained linear tail chains of PS and cyclic head chains of PEO were synthesized by combination of glaser coupling with living anionic polymerization (LAP) and ring-opening polymerization (ROP). Firstly, the functionalized polystyrene-glycerol (PS-Gly) with two active hydroxyl groups at ω end was synthesized by LAP of St and the subsequent capping with 1-ethoxyethyl glycidyl ether (EEGE) and then deprotection of protected hydroxyl group in acid condition. Then, using PS-Gly as macro-initiator, the ROP of EO was carried out using diphenylmethylpotassium(DPMK) as co-catalyst for AB2 star-shaped copolymers PS-b-(PEO-OH)2, and the alkyne group was introduced onto PEO arm end for PS-b-(PEO-Alkyne)2. Finally, The intramolecular cyclization was carried out by glaser coupling reaction in pyridine /Cu(I)Br /N,N,N',N'',N''-pentamethyldiethylenetri-amine (PMDETA) system under room temperature, and tadpole-shaped PS-b-(c-PEO) with high efficiency (almost 100%) was formed. The target copolymers and their intermediates were well characterized by SEC, 1H NMR and FT-IR in details. The critical micelle concentration (CMC) and the thermal properties were also determined and compared to investigate the influence of architecture on properties. The results showed that tadpole-shaped copolymers had higher CMC values and lower Tm, Tc, Xc than that of their precursors of star-shaped copolymers.
	TO cite this article:WANG Guowei,HU Bin,FAN Xiaoshan, et al. Synthesis of Amphiphilic Tadpole-shaped PS-b-(c-PEO) Copolymers by the Combination of Glaser Coupling with Living Anionic Polymerization and Ring-opening Polymerization[OL].[23 May 2011] http://en.paper.edu.cn/en_releasepaper/content/4428451


	2. Effect of pi-pi Stacking on the Self-Assembly of Azomethine Type Rod-Coil Molecules
	YU Yingfeng,LIU Yi,ZHONG Xinhui,SU Huihuang,GAN Wenjun
	Chemistry 27 December 2010
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	Abstract:The role of pi-pi stacking in the molecular self-assembly behavior, the mesogenic transitions and fluorescent properties was investigated for coil-rod-coil molecules with two ethylene oxide coil units and aromatic azomethine rod units. Three kinds of rod-coil molecules with different rod units were synthesized and characterized by differential scanning calorimetry (DSC), polarized optical microscope (POM), X-ray diffraction (XRD), transmission electronic microscope (TEM), absorption and photoluminescence. With strong pi-pi stacking interaction between coplanar molecules, fibril structure in solution is formed while the fluorescent emission shows a quick increase of the intensity of short wavelength with the increase of solution concentration. Spherical aggregations in solution are formed with the increase of the twisting of the rod segment plane, which decreases the pi-pi stacking interaction and thus enlarges the intermolecular spacing. Simulation work carried out in Material Studio corresponds well with the experiment results of aggregations and mesogenic transitions.
	TO cite this article:YU Yingfeng,LIU Yi,ZHONG Xinhui, et al. Effect of pi-pi Stacking on the Self-Assembly of Azomethine Type Rod-Coil Molecules[OL].[27 December 2010] http://en.paper.edu.cn/en_releasepaper/content/4401541

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	3. Highly soluble poly (aryl-ether benzoxazole) random copolymers by aromatic nucleophilic polycondensation: Synthesis and properties
	Jinhuan Li,Haiyang Wang,Ruihai Wang
	Chemistry 24 December 2010
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	Abstract:Aromatic polybenzoxazoles (PBOs) are very promising materials for civil, aerospace and electronics industries due to their outstanding mechanical properties, good thermooxidative stability and chemical resistance along with a lot of other superior properties. However the feasibility of the wide applications is hindered due to the difficulty of their processing derived from the very rigid structure. In this contribution poly(aryl-ether benzoxazole) random copolymers (PAEXBOx) were prepared by nucleophilic polycondensation. The introduction of ary-ether ketone and aryl-ether sulfone segments along with flexible linkages and bulky groups provides PAEXBOx with good solubility in organic solvents. This guarantees the possible good processiblity. The PAEXBOx exhibited as good thermal stability (> 460 oC) as the PBO, the poly(aryl ether ketone) (PAEK) and the poly(aryl ether sulfone) (PAES). The glass transition temperature (269-296 oC) of the PAEXBOx is improved compared with that of the PAEK and PAES. The structure effect on the copolymer properties was systematically discussed.
	TO cite this article:Jinhuan Li,Haiyang Wang,Ruihai Wang. Highly soluble poly (aryl-ether benzoxazole) random copolymers by aromatic nucleophilic polycondensation: Synthesis and properties[OL].[24 December 2010] http://en.paper.edu.cn/en_releasepaper/content/4400610


	4. High Spin Co(II) Complexes for Catalytic Chain Transfer Polymerization of Methyl Methacrylate
	Luo Xiongxiong ,Xu Shansheng ,Wang Baiquan
	Chemistry 16 December 2010
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	Abstract:In this paper the first high spin cobalt (II) complexes system Co(PPh3)X2/AIBN for the chain transfer polymerization of MMA were developed. The chain transfer constant CT is low (1), and polymers with high molecular weight (up to 100000) and narrow polydispersities (ca 1.40) can be obtained. The molecular weight of polymers increases linearly with the ratio of monomer to initiator. So the molecular weight of polymer can be easily designed and achieved by adjusting the ratio of monomer to initiator.
	TO cite this article:Luo Xiongxiong ,Xu Shansheng ,Wang Baiquan . High Spin Co(II) Complexes for Catalytic Chain Transfer Polymerization of Methyl Methacrylate[OL].[16 December 2010] http://en.paper.edu.cn/en_releasepaper/content/4395761


	5. Hyperbranched Polyolefin Generated from Living Polymerization of 4-Methyl-1-Pentene Catalyzed by a α-Diimine Palladium Catalyst
	Wu Qing,Guo Lihua,Gao Haiyang
	Chemistry 16 December 2010
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	Abstract:Branched α-olefin 4-methyl-1-pentene (4MP) was polymerized with a cationic α-diimine palladium catalyst. Influences of polymerization parameters including reaction temperature and monomer concentration on polymer architecture were evaluated in detail. Increasing temperature and lowering monomer concentration can lead to the form of more hyperbranched polyolefin because of chain walking. At 0 ℃, hyperbranched polyolefins were generated from living polymerization of 4-methyl-1-pentene with α-diimine palladium catalyst.
	TO cite this article:Wu Qing,Guo Lihua,Gao Haiyang. Hyperbranched Polyolefin Generated from Living Polymerization of 4-Methyl-1-Pentene Catalyzed by a α-Diimine Palladium Catalyst[OL].[16 December 2010] http://en.paper.edu.cn/en_releasepaper/content/4398243


	6. Synthesis and Characterization of a Well-defined Amphiphilic Block Copolymer and Its Paclitaxel Prodrug from MPEG and Oligomer of Glycolic Acid
	Zhang Li ,Fu Jinyan ,Wu Ping ,Xia Zhixiang ,Zhang Xuefei
	Chemistry 29 November 2010
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	Abstract:A well-defined amphiphilic block copolymer was synthesized by coupling carboxyl-terminated methoxy Poly (ethylene glycol) (MPEG) with a hydroxyl-terminated octamer of glycolic acid which was obtained by a stepwise synthetic procedure with the end-group protection and de-protection. The block copolymer had a polydispersity index (PDI) of 1.01 determined by GPC. It was further coupled to paclitaxel to form a prodrug of paclitaxel. The paclitaxel content in the prodrug was ca. 10% and its PDI was 1.02. The antitumor activity of the conjugate against human lung carcinoma A549 cells was evaluated by MTT assay. The results showed that paclitaxel can be released from the conjugate without losing cytotoxicity. Therefore, the well-defined amphiphilic block copolymer from MPEG and oligomer of glycolic acid would potentially provide novel opportunities to obtain reproducible pharmacokinetic behavior in design of drug delivery system.
	TO cite this article:Zhang Li ,Fu Jinyan ,Wu Ping , et al. Synthesis and Characterization of a Well-defined Amphiphilic Block Copolymer and Its Paclitaxel Prodrug from MPEG and Oligomer of Glycolic Acid[OL].[29 November 2010] http://en.paper.edu.cn/en_releasepaper/content/4393170


	7. Synthesis of Biodegradable and Biocompatible Polymer Brushes with High Grafting Density on the Surface of Nano-hydroxyapatite by Combination of ATRP and ROP
	Zeng Liang ,Wang Haibo ,Fu Guoxin ,Jiang Jianwei ,Zhang Xuefei
	Chemistry 16 November 2010
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	Abstract:A facile strategy for growing biodegradable and biocompatible polymer brushes with high grafting density on the surface of nano-hydroxyapatite (n-HAP) by combination of Atom Transfer Radical Polymerization (ATRP) and Ring-Opening Polymerization (ROP) will be presented. Firstly, ATRP was used to graft poly (2-hydroxyethyl methacrylate) (PHEMA) onto the n-HAP surface. Then, the hydroxyls groups introduced onto the n-HAP were used initiating the ROP of ε-caprolactone for constructing polymer brushes on the n-HAP. The functionalized n-HAP was characterized by FT-IR, 13C Solid-State Cross-Polarization Magic-Angle-Spinning (13C CP/MAS), Thermal Gravimetric Analysis (TGA), X-ray Diffraction (XRD), and Transmission Electron Microscopy (TEM) measurements. The measurement results demonstrated that the biodegradable and biocompatible polymer brushes have been grown successfully and the average thickness of grafted polymer layers can be controlled well by adjusting the feed ratio. This convenient strategy can be used extended to prepare other functional/multifunctional polymer brushes in the future and open an avenue for further grafting therapeutic molecules and other biomolecule on the n-HAP.
	TO cite this article:Zeng Liang ,Wang Haibo ,Fu Guoxin , et al. Synthesis of Biodegradable and Biocompatible Polymer Brushes with High Grafting Density on the Surface of Nano-hydroxyapatite by Combination of ATRP and ROP[OL].[16 November 2010] http://en.paper.edu.cn/en_releasepaper/content/4391262


	8. β-cyclodextrin grafting hyperbranched polyglycerols as carriers for nasal insulin delivery
	Zhang Xuejiao,Zhang Xinge,Gao Xiujun,Shu Shunjun
	Chemistry 27 August 2010
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	Abstract:We prepared a β-CD functionalized hyperbranched polyglycerol (HPG) with the purpose of enhancing the nasal transport of insulin in rats. Insulin-loaded HPG-g-CD nanoparticles (NPs) were prepared and the size of the NPs ranged from 198 to 340 nm with a positive charge. The NPs exhibited a great capacity of associating insulin, reaching the efficiency as high as 88.21%. In vitro release showed that the release rate of insulin was much faster under acidic condition than physiological condition. In vitro cytotoxicity against Caco-2 cells showed that HPG-g-CDs had good biocompatibility. The in vivo evaluation in rats demonstrated that insulin-loaded HPG-g-CD NPs had the ability to significantly decrease the blood glucose concentrations. Furthermore, the capability of HPG-g-CD NPs to cross the nasal mucosal epithelia was proved by confocal laser scanning microscopy (CLSM). Consequently, the results suggest that the HPG-g-CD NPs are promising carriers for nasal insulin delivery.
	TO cite this article:Zhang Xuejiao,Zhang Xinge,Gao Xiujun, et al. β-cyclodextrin grafting hyperbranched polyglycerols as carriers for nasal insulin delivery[OL].[27 August 2010] http://en.paper.edu.cn/en_releasepaper/content/4383450


	9. 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


	10. 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
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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 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

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