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1.
Synthesis and Characterization of Novel Glycerol‐Derived Polycarbonates with Pendant Hydroxyl Groups
Hujie Mei Zhenlin Zhong Feifu Long Renxi Zhuo 《Macromolecular rapid communications》2006,27(22):1894-1899
Summary: A novel type of glycerol‐derived, water‐soluble polycarbonate with pendant, primary hydroxyl groups was prepared from 2‐(2‐benzyloxyethoxy)trimethylene carbonate (BETC). Ring‐opening polymerization of BETC and 2,2‐dimethyltrimethylene carbonate (DTC) gave narrow distribution of homopolymers or random copolymers with high molecular weights. The protecting benzyl groups were removed by catalyzed hydrogenation at atmosphere H2 pressure to give hydroxyl polycarbonates without observable changes on the polymer backbone and molecular weight distribution. The hydrophilicity of the copolymers increases with the increase in the hydrophilic glycerol‐derived carbonate content.
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Raphaël Riva Wenda Lazzari Leen Billiet Filip Du Prez Christine Jérôme Philippe Lecomte 《Journal of polymer science. Part A, Polymer chemistry》2011,49(7):1552-1563
This article reports on the synthesis of a new pH‐sensitive amphiphilic A2B mikto‐arm star‐shaped aliphatic copolyester [with A = poly(ε‐caprolactone) and B = tertiary amine‐bearing poly(ε‐caprolactone)] with two hydrophobic arms and one hydrophilic arm when protonated at pH = 5.5. First, the ring‐opening polymerization of ε‐caprolactone (εCL) was initiated by an aliphatic diol substituted by an alkyne. The copper(I) catalyzed azide‐alkyne cycloaddition (CuAAC) was use to convert the alkyne into a hydroxyl group prone to initiate the ring‐opening copolymerization of γ‐bromo‐ε‐caprolactone (γBrεCL) and εCL. After the substitution of the bromide atoms into azide functions, the N,N‐dimethylprop‐2‐yn‐1‐amine was grafted onto the azide bearing PCL arm by CuAAC, with the purpose to make the B arm hydrophilic at low pH. The precursors of the A2B copolymers were characterized by 1H NMR, SEC, and MALDI‐TOF. As expected, the A2B copolyester was soluble into water at pH = 5. The formation of polymersomes in water at pH 5 was assessed by DLS and TEM analyses. The effects of the architecture and the molecular weight of the A2B copolymers on the formation of polymersomes were investigated. Moreover, the versatility of our approach was demonstrated by the synthesis of an AB2 star‐shaped copolyester. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
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Jun Ling Zhiquan Shen Weipu Zhu 《Journal of polymer science. Part A, Polymer chemistry》2003,41(9):1390-1399
Rare‐earth (Nd, Y) p‐tert‐butylcalix[n]arene (n = 4, 6, and 8) complexes without coligands were synthesized from rare‐earth isopropoxides in toluene. The products were characterized as the following structures: [C4(OH)O3 · CH3C6H5]Nd ( 4 ), [C6(OH)2O4 · CH3C6H5]3Ln4 [Ln = Nd ( 5 ), Y ( 6 )], and [C8(OH)2O6 · CH3C6H5]Nd2 ( 7 ). 2,2‐Dimethyl trimethylene carbonate (DTC) can be polymerized with complexes 4 – 7 alone as the initiator. PolyDTC (weight‐average molecular weight: 5700, polydispersity index: 1.11, measured by gel permeation chromatography) initiated by complex 5 was obtained with a conversion of 69.1% within 6 h in toluene at 80 °C. The thermal behavior of polyDTC has been compared with the published data. The DTC ring is opened via acyl‐oxygen bond cleavage with end‐group examination. NMR analyses of the polymerization reaction mixture indicated that the polymerization proceeds via a coordination‐insertion mechanism. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1390–1399, 2003 相似文献
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A Rare Example of the Formation of Polystyrene‐Grafted Aliphatic Polyester in One‐Pot by Radical Polymerization 下载免费PDF全文
Yinfeng Shi Dr. Zhicheng Zheng Prof. Dr. Seema Agarwal 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(24):7419-7428
The radical copolymerization of cyclic ester β‐propiolactone (β‐PL) with styrene (St) at 120 °C, with a complete range of monomer ratios, is a rare example of a system providing graft copolymers (PSt‐g‐β‐PL) in one pot. The structure of the resulting β‐PL–St copolymers was proven by using a combination of different characterization techniques, such as 1D and 2D NMR spectroscopy and gel permeation chromatography (GPC), before and after alkaline hydrolysis of the polymers. The number of grafting points increased with an increasing amount of β‐PL in the feed. A significant difference in the reactivity of St and β‐PL and radical chain‐transfer reactions at the polystyrene (PSt) backbone, followed by combination with the active growing poly(β‐PL) chains, led to the formation of graft copolymers by a grafting‐onto mechanism. 相似文献
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Hiroyuki Matsukizono Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2016,54(4):487-497
Ring‐opening polymerization (ROP) of monofunctional neopentylglycol carbonate (NPGC) with or without bifunctional di(trimethylolpropane) carbonate (DTMPC), which are derived from available corresponding alcohols, affords linear polycarbonates or covalently‐linked polycarbonate networks, respectively. A series of available ethanol amine derivatives having the different numbers of 2‐hydroxylethyl arms (N,N,N’,N’‐tetrakis(2‐hydroxyethyl)ethylenediamine, triethanolamine, N‐methyldiethanolamine or N,N‐dimethylethanolamine) initiates the ROP of NPGC to afford star‐shaped, telechelic, or linear polycarbonates bearing tertiary amines with well‐controlled molecular weights and relatively narrow polydispersities Furthermore, the copolymerization of NPGC and DTMPC in the presence of these initiators readily gives tertiary amine‐modified polycarbonate films with well transparency and flexibility. These amino groups are easily converted to ammonium salts by protonation with acids, while the quaternization with benzyl bromide is strongly affected by the steric hindrance of these amines. N‐Methyldiethanolamine or N,N‐dimethylethanolamine residues in these films react easily with benzyl bromide to give quaternary ammonium salt‐functionalized films. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 487–497 相似文献
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Yoshio Yamamoto Sachiko Kaihara Kazunobu Toshima Shuichi Matsumura 《Macromolecular bioscience》2009,9(10):968-978
High‐molecular‐weight PTeMC and PHMC were prepared by the lipase‐catalyzed polymerization of butane‐1,4‐diol or hexane‐1,6‐diol and diphenyl carbonate via the formation of a cyclic dimer by a green process. Cyclic carbonate dimers were prepared by the lipase‐catalyzed condensation of diphenyl carbonate with butane‐1,4‐diol or hexane‐1,6‐diol in dilute toluene solution using an immobilized lipase from Candida antarctica, and was followed by the ring‐opening polymerization of the cyclic dimer in bulk with the same lipase to produce PTeMC with = 119 000 g · mol?1 and PHMC with = 399 000 g · mol?1, respectively. Additionally, enzymatic polymerization of cyclic carbonate dimer was analyzed with respect to the Km and Vmax for the lipase.
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The thermal ring‐opening polymerization of 5‐benzyloxy‐trimethylene carbonate (BTMC) in bulk in the absence of any catalyst resulted in high molecular weight poly(BTMC) ( = 80 300) and subsequent catalytic hydrogenolysis resulted in functional poly(5‐hydroxyl‐trimethylene carbonate) (PHTMC). Similar spontaneous polymerization of BTMC in the presence of PEG ( = 2 000) as a macroinitiator can provide amphiphilic block polymers. The results revealed that the thermal non‐catalyst (co)polymerization of BTMC is a highly attractive preparative method because of the lack of usage of toxic initiators or catalysts. Furthermore, an evaluation of the degradation and cytotoxicity of PHTMC demonstrated enhanced degradability compared to poly(trimethylene carbonate) and similar toxicity compared to PLGA, showing PHTMC to be a promising biomaterial.
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Tobias Rudolph Adam Nunns Steffi Stumpf Christian Pietsch Felix H. Schacher 《Macromolecular rapid communications》2015,36(18):1651-1657
The step‐wise solution self‐assembly of double crystalline organometallic poly(ferrocenyldimethylsilane)‐block‐poly(2‐iso‐propyl‐2‐oxazoline) (PFDMS‐b‐PiPrOx) diblock copolymers is demonstrated. Two block copolymers are obtained by copper‐catalyzed azide‐alkyne cycloaddition (CuAAC), featuring PFDMS/PiPrOx weight fractions of 46/54 (PFDMS30‐b‐PiPrOx75) and 30/70 (PFDMS30‐b‐PiPrOx155). Nonsolvent induced crystallization of PFDMS in acetone leads in both cases to cylindrical micelles with a PFDMS core. Afterward, the structures are transferred into water for sequential temperature‐induced crystallization of the PiPrOx corona, leading to hierarchical double crystalline superstructures, which are investigated using scanning electron microscopy, wide angle X‐ray scattering, and differential scanning calorimetry.
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Xiaojin Zhang Mengmeng Cai Zhenlin Zhong Renxi Zhuo 《Macromolecular rapid communications》2012,33(8):693-697
A water‐soluble polycarbonate with dimethylamino pendant groups, poly(2‐dimethylaminotrimethylene carbonate) (PDMATC), is synthesized and characterized. First, the six‐membered carbonate monomer, 2‐dimethylaminotrimethylene carbonate (DMATC), is prepared via the cyclization reaction of 2‐(dimethylamino)propane‐1,3‐diol with triphosgene in the presence of triethylamine. Although the attempted ring‐opening polymerization (ROP) of DMATC with Sn(Oct)2 as a catalyst fails, the ROP of DMATC is successfully carried out with Novozym‐435 as a catalyst to give water‐soluble aliphatic polycarbonate PDMATC with low cytotoxicity and good degradability. 相似文献
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Chungmi Yang Ji Eun Hwang Kyuseok Kim Byeong‐Su Kim 《Journal of polymer science. Part A, Polymer chemistry》2017,55(24):4013-4019
We report a one‐pot synthesis of hyperbranched polyglycerols possessing amino functionality by using a novel Boc‐protected aminoethanol glycidyl ether monomer (BAG). A series of hyperbranched Boc‐protected polyamino glycerols (PBAG) were prepared through a one‐pot anionic ring opening multibranching polymerization to yield PBAG with controlled molecular weights (3500–17400 g/mol). Subsequent deprotection of PBAG yielded hyperbranched polyamino glycerols (PAG) with a globular polymeric structure that comprises a randomly branched structure with a large number of functional amine and hydroxyl groups. 1H, 13C, and 15N‐NMR, GPC, and MALDI‐TOF measurements confirmed the successful polymerization of the hyperbranched PAG polymers. With its superior biocompatibility of PAG, we anticipate the prospective potentials for the applications in biological and biomedical fields. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 4013–4019 相似文献
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Saide Cui Xin Wang Zhenjiang Li Qiguo Zhang Wenzhuo Wu Jingjing Liu Hao Wu Cheng Chen Kai Guo 《Macromolecular rapid communications》2014,35(22):1954-1959
Novel amphiphilic polypeptoid‐polyester diblock copolymers based on poly(sarcosine) (PSar) and poly(ε‐caprolactone) (PCL) are synthesized by a one‐pot glovebox‐free approach. In this method, sarcosine N‐carboxy anhydride (Sar‐NCA) is firstly polymerized in the presence of benzylamine under N2 flow, then the resulting poly(sarcosine) is used in situ as the macroinitiator for the ring‐opening polymerization (ROP) of ε‐caprolactone using tin(II) octanoate as a catalyst. The degree of polymerization of each block is controlled by various feed ratios of monomer/initiator. The diblock copolymers with controlled molecular weight and narrow molecular weight distributions (ĐM < 1.2) are characterized by 1H NMR, 13C NMR, and size‐exclusion chromatography. The self‐assembly behavior of PSar‐b‐PCL in water is investigated by dynamic light scattering (DLS) and transmission electron microscopy. DLS results reveal that the diblock copolymers associate into nanoparticles with average hydrodynamic diameters (DH) around 100 nm in water, which may be used as drug delivery carriers.
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Chunbo Yang Zhengzheng Shi Cong Feng Rui Li Sihao Luo Xiangfeng Li Liping Ruan 《Macromolecular bioscience》2020,20(6)
In this study, an adjustable pH‐responsive drug delivery system using mesoporous silica nanoparticles (MSNs) as the host materials and the modified polypeptides as the nanovalves is reported. Since the polypeptide can self‐assemble via electrostatic interaction at pH 7.4 and be disassembled by pH changes, the modified poly(l ‐lysine) and poly(l ‐glutamate) are utilized for pore blocking and opening in the study. Poly(l ‐lysine)‐MSN (PLL‐MSN) and poly(l ‐glutamate)‐MSN (PLG‐MSN) are synthesized via the ring opening polymerization of N‐carboxyanhydrides onto the surface of mesoporous silica nanoparticles. The successful modification of the polypeptide on MSN is proved by Zeta potential change, X‐ray photoelectron spectroscopy (XPS), solid state NMR, and MALDI‐TOF MS. In vitro simulated dye release studies show that PLL‐MSN and PLG‐MSN can successfully load the dye molecules. The release study shows that the controlled release can be constructed at different pH by adjusting the ratio of PLL‐MSN to PLG‐MSN. Cellular uptake study indicates that the drug is detected in both cytoplasm and nucleus, especially in the nucleus. In vitro cytotoxicity assay indicates that DOX loaded mixture nanoparticles (ratio of PLL‐MSN to PLG‐MSN is 1:1) can be triggered for drug release in HeLa cells, resulting in 88% of cell killing. 相似文献
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Liya Zhang Chunmei Song Jiahui Yu Dan Yang Meiran Xie 《Journal of polymer science. Part A, Polymer chemistry》2010,48(22):5231-5238
Shell‐functionalized polymeric nanoparticle was prepared through the method of polymerization‐induced self‐assembly of block copolymers [poly(2,3‐bis(2‐bromoisobutyryloxymethyl)‐5‐norbornene)‐block‐poly(7‐oxanorborn‐5‐ene‐exo‐exo‐2,3‐dicarboxylic acid dimethyl ester), PBNBE‐b‐PONBDM] via one‐pot ring‐opening metathesis polymerization of 2,3‐bis(2‐bromoisobutyryloxymethyl)‐5‐norbornene (BNBE) and 7‐oxanorborn‐5‐ene‐exo‐exo‐2,3‐dicarboxylic acid dimethyl ester (ONBDM) in a selective solvent. The compositions and the molecular weights of the copolymers were estimated by 1H‐NMR and gel permeation chromatography. The micelles were characterized by dynamic light scattering, transmission electron micrograph, and atomic force microscopy. The results indicated that the spherical micelles constructed with bromine‐bearing PBNBE shell and PONBDM core were stable and reproducible in toluene. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
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Jamie M. Messman Robson F. Storey 《Journal of polymer science. Part A, Polymer chemistry》2006,44(23):6817-6835
Ethylene glycol (EG) initiated, hydroxyl‐telechelic poly(L ‐lactide) (PLLA) was employed as a macroinitiator in the presence of a stannous octoate catalyst in the ring‐opening polymerization of 5‐methyl‐5‐benzyloxycarbonyl‐1,3‐dioxan‐2‐one (MBC) with the goal of creating A–B–A‐type block copolymers having polycarbonate outer blocks and a polyester center block. Because of transesterification reactions involving the PLLA block, multiblock copolymers of the A–(B–A)n–B–A type were actually obtained, where A is poly(5‐methyl‐5‐benzyloxycarbonyl‐1,3‐dioxan‐2‐one), B is PLLA, and n is greater than 0. 1H and 13C NMR spectroscopy of the product copolymers yielded evidence of the multiblock structure and provided the lactide sequence length. For a PLLA macroinitiator with a number‐average molecular weight of 2500 g/mol, the product block copolymer had an n value of 0.8 and an average lactide sequence length (consecutive C6H8O4 units uninterrupted by either an EG or MBC unit) of 6.1. For a PLLA macroinitiator with a number‐average molecular weight of 14,400 g/mol, n was 18, and the average lactide sequence length was 5.0. Additional evidence of the block copolymer architecture was revealed through the retention of PLLA crystallinity as measured by differential scanning calorimetry and wide‐angle X‐ray diffraction. Multiblock copolymers with PLLA crystallinity could be achieved only with isolated PLLA macroinitiators; sequential addition of MBC to high‐conversion L ‐lactide polymerizations resulted in excessive randomization, presumably because of residual L ‐lactide monomer. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6817–6835, 2006 相似文献
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Polyglycidol Based Amphiphilic Double‐Comb Copolymers and Their Self‐Association in Aqueous Solution
Firat Ozdemir Helmut Keul Ahmed Mourran Martin Moeller 《Macromolecular rapid communications》2011,32(13):1007-1013
Herein, we report synthesis and self‐association properties of amphiphilic double‐comb polymers with polyglycidol backbones. First, a bifunctional polyglycidol precursor is synthesized via monomer activated anionic polymerization. Next, two efficient and orthogonal polymer analogous reactions are carried out for grafting hydrophilic oligoethylene glycol side chains and hydrophobic linear aliphatic side‐chains. The polymers are analyzed by means of NMR, GPC, and DSC. From the DSC analysis of the bulk samples it is evident that aliphatic side chains segregate from the polar backbone and thus crystallize. Furthermore, in aqueous media the double‐comb polymers spontaneously self‐assemble to form a multilayer structure. The present results pave a way to tailor and design amphiphilic polymers based on glycidols. Major advantages are spontaneous self‐assembly in water and the possibility to form onion polymersomes relevant to encapsulation.
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Il Kim Sang Mook Kim Chang‐Sik Ha Dae‐Won Park 《Macromolecular rapid communications》2004,25(8):888-893
Summary: The reaction of 2‐lithio‐6‐methylpyridine or 2‐lithiopyridine and the appropriate diaryl ketone followed by hydrolysis yields 6‐Me‐pyCAr2OH pyridine alcohols or pyCAr2OH pyridine alcohols. The reactions of zinc acetate with 1 equiv. of the lithiated products of the ligands proceed rapidly to afford LiOAc salt and mono‐ligand complexes (6‐Me‐pyCAr2O)Zn(OAc) and (pyCAr2O)Zn(OAc), respectively, in high yield. The copolymerizations of carbon dioxide with cyclohexene oxide were investigated. The (6‐Me‐pyCAr2O)Zn(OAc) showed moderate yield and CO2 incorporation. The [6‐Me‐pyC(4‐Cl‐C6H4)2O]Zn(OAc) complex gave large polymers with high proportions of carbonate linkage (>60%) and narrow polydispersity, indicating single active sites.