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1.
ATRP of 2‐(N,N‐dimethylamino)ethyl acrylate (DMAEA) was investigated using CuBr or CuCl with different multidentate ligands. The catalyst was found active for DMAEA polymerization when ligated with tris[2‐(N,N‐dimethylamino)ethyl]amine. Good control over molecular weight was achieved, but quaternization of the terminal monomeric/polymeric tertiary amine by the C Br group of polyDMAEA caused chain termination. Using a chloride‐based system helped to suppress chain termination. Amphiphilic poly(methyl acrylate)‐block‐polyDMAEA was synthesized using polyMA as a macroinitiator.
2.
The monomer 3‐ethyl‐1‐vinyl‐2‐pyrrolidone ( 3 ) and the homopolymer poly(3‐ethyl‐1‐vinyl‐2‐pyrrolidone) ( 5 ) have been synthesized. Polymer 5 is soluble in water and shows a critical temperature (Tc) of 27 °C. The presence of cyclodextrin causes a slight shift of the Tc. The lower critical solution temperature (LCST) could be varied between 27 and 40 °C by copolymerization with N‐vinyl‐2‐pyrrolidone. A linear correlation between the Tc and the copolymer composition is observed.
3.
A series of random copolymers and block copolymers containing water‐soluble 4AM and fluorescent VAK are synthesized by NMP. The homopolymerizations of 4AM and VAK and 4AM/VAK random copolymerization are performed in 50 wt% DMF using 10 mol% SG1, resulting in a linear increase in versus conversion, and final polymers with narrow molecular weight distributions ( < 1.4). Reactivity ratios rVAK = 0.64 ± 0.52 and r4AM = 0.86 ± 0.66 are obtained for the 4AM/VAK random copolymerization. In addition, a poly(4AM) macroinitiator is used to initiate a surfactant‐free suspension polymerization of VAK. After 2.5 h, the resulting amphiphilic block copolymer has = 12.6 kg · mol?1, = 1.48, molar composition FVAK = 0.38 with latex particle sizes between 270 and 475 nm.
4.
Yasuyuki Kagawa Masahiro Kawasaki Per B. Zetterlund Hideto Minami Masayoshi Okubo 《Macromolecular rapid communications》2007,28(24):2354-2360
Direct atom transfer radical polymerization (ATRP) of iso‐butyl methacrylate in microemulsion has been performed successfully for the first time. ATRP was performed at 40 °C with different emulsifier systems: i) the cationic emulsifier n‐tetradecyltrimethylammonium bromide (TTAB); and ii) mixed emulsifier systems based on TTAB and the non‐ionic emulsifiers Emulgen 911 or Emulgen 931. All polymerizations proceeded in a controlled/living fashion, and the microemulsions were transparent with particle diameters less than 15 nm. The emulsifier system TTAB/Emulgen 911 exhibited better control than TTAB only. This is proposed to be caused by complex formation between Emulgen 911 in the organic phase and CuBr2 (the deactivator), thus reducing the extent of exit of CuBr2 to the aqueous phase. The more hydrophilic Emulgen 931 did not lead to improved control.
5.
Well‐defined PEO‐b‐PMMA was prepared, initiated by macroinitiator PEO‐Br, by means of ATRP, where esterification of the terminal hydroxyl group of PEO with 2‐bromoisobutyryl bromide yielded a macroinitiator PEO‐Br. Highly ordered microporous films (hexagonal pattern) were constructed by emulsion micelles of such amphiphilic diblock copolymer formed from a solution with CHCl3/H2O/THF = 100:5:10 (v/v). We also constructed the microporous films using diblock copolymer by the current water‐assisted method.
6.
Si‐Xue Cheng Zhi‐Mei Miao Lian‐Sheng Wang Ren‐Xi Zhuo 《Macromolecular rapid communications》2003,24(18):1066-1069
A series of novel biodegradable random copolymers of 5‐benzyloxy‐1,3‐dioxan‐2‐one (5‐benzyloxy‐trimethylene carbonate, BTMC) and glycolide were synthesized by ring‐opening polymerization. The copolymers were characterized by nuclear magnetic resonance (NMR) spectroscopy and gel permeation chromatography (GPC). The incorporation of BTMC units into the copolymer chains results in good solubility of the polymers in common solvents. The in vitro degradation rate can be tailored by adjusting the composition of the copolymers.
7.
Laetitia Mespouille Magali Vachaudez Fabian Suriano Pascal Gerbaux Olivier Coulembier Philippe Dege Robert Flammang Philippe Dubois 《Macromolecular rapid communications》2007,28(22):2151-2158
Well‐defined amphiphilic PCL‐b‐PDMAEMA block copolymers were successfully synthesized by a combination of ATRP and “click” chemistry following either a commutative two‐step procedure or a straightforward one‐pot process using CuBr · 3Bpy as the sole catalyst. Compared to the traditional coupling method, combining ATRP and click chemistry even in a “one‐pot” process allows the preparation of PCL‐b‐PDMAEMA diblock copolymers characterized by a narrow molecular weight distribution and quantitative conversion of azides and alkynes into triazole functions. Moreover, the amphiphilic character of these copolymers was demonstrated by surface tension measurements and critical micellization concentration was calculated.
8.
Tao Wu Ying Mei Chang Xu H. C. Michelle Byrd Kathryn L. Beers 《Macromolecular rapid communications》2005,26(13):1037-1042
Summary: Block copolymers of poly(ethylene oxide‐block‐2‐hydroxypropyl methacrylate) (PEO‐b‐PHPMA) with a range of molecular masses of the PHPMA block were obtained by controlled radical polymerization on a chip (CRP chip) using a PEO macroinitiator. A series of well‐controlled polymerizations were carried out at different pumping rates or reaction times with a constant ratio of monomer to initiator. The stoichiometry of the reactants was also adjusted by varying relative flow rates to change the reactant concentrations.
9.
Summary: A multistep synthetic procedure for preparing novel C60‐anchored two‐armed poly(tert‐butyl acrylate) was developed. First, two‐armed poly(tert‐butyl acrylate) bearing a malonate ester core with well‐controlled molecular weight was synthesized through atom transfer radical polymerization. The effective Bingel reaction between C60 and the well‐defined polymer was then carried out to yield C60‐anchored polymer. GPC, 1H NMR, and UV‐vis spectroscopy indicated that the C60‐anchored polymer was a monosubstituted and ‘closed’ 6,6‐ring‐bridged methanofullerene derivative.
10.
Summary: A highly active and versatile CuBr2/N,N,N′,N′‐tetra[(2‐pyridal)methyl]ethylenediamine (CuBr2/TPEN)‐tertiary amine catalyst system has been developed for atom transfer radical polymerization via activator‐generated‐by‐electron‐transfer (AGET ATRP). The catalyst mediates good control of the AGET ATRPs of methyl acrylate, methyl methacrylate, and styrene at 1 mol‐% catalyst relative to initiator. A mechanism study shows that tertiary amines such as triethylamine reduces the CuBr2/TPEN complex to CuBr/TPEN.
11.
1‐Vinyl‐2‐(hydroxymethyl)imidazole ( 2 ) is synthesized by a procedure described in the literature. Corresponding copolymers with upper critical solution temperature (UCST)‐type transitions in water and high‐glass transition temperatures (Tg) are prepared by free radical copolymerization with N‐vinylimidazole ( 1 ). Depending on the copolymer composition, the cloud point can be varied between 19 and 41 °C. As the copolymer composition is identical with the monomer feed ratio, the cloud point can be easily tuned in the desired range. Furthermore, a distinctive pH‐dependence and salt effect can be observed.
12.
Nadia Hundt Quan Hoang Hien Nguyen Prakash Sista Jing Hao John Servello Kumaranand Palaniappan Mussie Alemseghed Michael C. Biewer Mihaela C. Stefan 《Macromolecular rapid communications》2011,32(3):302-308
Poly(3‐hexylthiophene)‐b‐poly(γ‐benzyl‐L ‐glutamate) (P3HT‐b‐PBLG) rod–rod diblock copolymer was synthesized by a ring‐opening polymerization of γ‐benzyl‐L ‐glutamate‐N‐carboxyanhydride using a benzylamine‐terminated regioregular P3HT macroinitiator. The opto‐electronic properties of the diblock copolymer have been investigated. The P3HT precursor and the P3HT‐b‐PBLG have similar UV–Vis spectra both in solution and solid state, indicating that the presence of PBLG block does not decrease the effective conjugation length of the semiconducting polythiophene segment. The copolymer displays solvatochromic behavior in THF/water mixtures. The morphology of the diblock copolymer depends upon the solvent used for film casting and annealing results in morphological changes for both films deposited from chloroform and trichlorobenzene.
13.
Hailiang Zhang Xiaoyi Sun Xiayu Wang Qi‐Feng Zhou 《Macromolecular rapid communications》2005,26(5):407-411
Summary: A novel ABC triblock copolymer with a rigid‐rod block was synthesized by atom transfer radical polymerization (ATRP). First, a poly(ethylene oxide) (PEO)‐Br macroinitiator was synthesized by esterification of PEO with 2‐bromoisobutyryl bromide, which was subsequently used in the preparation of a poly(ethylene oxide)‐block‐poly(methyl methacrylate) (PEO‐b‐PMMA) diblock copolymer by ATRP. A poly(ethylene oxide)‐block‐poly(methyl methacrylate)‐block‐poly{2,5‐bis[(4‐methoxyphenyl)oxycarbonyl]styrene} (PEO‐b‐PMMA‐b‐PMPCS) triblock copolymer was then synthesized by ATRP using PEO‐b‐PMMA as a macroinitiator.
14.
Thomas Defize Raphaël Riva Jean‐Marie Raquez Philippe Dubois Christine Jrme Michaël Alexandre 《Macromolecular rapid communications》2011,32(16):1264-1269
A new concept to build shape memory polymers (SMP) combining outstanding fixity and recovery ratios (both above 99% after only one training cycle) typical of chemically crosslinked SMPs with reprocessability restricted to physically crosslinked SMPs is demonstrated by covalently bonding, through thermoreversible Diels–Alder (DA) adducts, star‐shaped poly(ε‐caprolactones) (PCL) end‐functionalized by furan and maleimide moieties. A PCL network is easily prepared by melt‐blending complementary end‐functional star polymers in retro DA regime, then by curing at lower temperature to favour the DA cycloaddition. Such covalent network can be reprocessed when heated again at the retro DA temperature. The resulting SMP shows still excellent shape memory properties attesting for its good recyclability.
15.
Yun Wang Lu Lu Hu Wang Dairen Lu Kang Tao Ruke Bai 《Macromolecular rapid communications》2009,30(22):1922-1927
A facile strategy for synthesis of α‐heterobifunctional polystyrenes is reported. The novel functional polystyrenes have been successfully synthesized via a combination of atom transfer radical polymerization (ATRP) and chemical modification of end‐functional groups. First, ε‐caprolactone end‐capped polystyrenes with controlled molecular weight and low polydispersity were prepared by ATRP of styrene using α‐bromo‐ε‐caprolactone (αBrCL) as an initiator. Then, removal of the terminal bromine atom was performed with iso‐propylbenzene in the presence of CuBr/PMDETA. Finally, ring‐opening modifications of the caprolactone group were carried out with amines, n‐butanol and H2O to produce novel polystyrenes containing two different functional groups at one end.
16.
Kristian Kempe Richard Hoogenboom Ulrich S. Schubert 《Macromolecular rapid communications》2011,32(18):1484-1489
The bulk polymerization of 2‐(dec‐9‐enyl)‐2‐oxazoline ( DecEnOx ), a fatty acid‐based monomer for the cationic ring‐opening polymerization, is reported. Furthermore, under optimal conditions, namely microwave heating at 100 °C, the bulk copolymerization with 2‐ethyl‐2‐oxazoline yielded well‐defined copolymers. Due to its pendant alkene groups DecEnOx ‐based polymers possess the potential to be modified in efficient thiol‐ene reactions. The functionalization with thiols, e.g., dodecanethiol and 2,3,4,6‐tetra‐O‐acetyl‐1‐thio‐β‐D ‐glycopyranose in “green” solvents is demonstrated.
17.
Frank Wiesbrock Richard Hoogenboom Caroline H. Abeln Ulrich S. Schubert 《Macromolecular rapid communications》2004,25(22):1895-1899
Summary: The ring‐opening cationic polymerization of 2‐ethyl‐2‐oxazoline was performed in a single‐mode microwave reactor as the first example of a microwave‐assisted living polymerization. The observed increase in reaction rates by a factor of 350 (6 h → 1 min) in the range from 80 to 190 °C could be attributed solely to a temperature effect as was clearly shown by control experiments and the determined activation energy. Because of the homogenous microwave irradiation, the polymerization could be performed in bulk or with drastically reduced solvent ratios (green chemistry).
18.
Viviane Fassina Carolina Ramminger Marcus Seferin Raquel S. Mauler Roberto F. de Souza Adriano L. Monteiro 《Macromolecular rapid communications》2003,24(11):667-670
The oxidative addition of benzyl chloride to Ni(cod)2 in the presence of 1,4‐bis(2,6‐diisopropylphenyl)acenaphthenediimine followed by chloride abstraction affords [(η3‐CH2C6H5)Ni(α‐diimine)][PF6] (α‐diimine = 1,4‐bis(2,6‐diisopropylphenyl)acenaphthenediimine) in 70% yield. The complex is active in ethylene polymerization in the presence of methylaluminoxane and under mild reaction conditions. The polyethylenes obtained are highly branched, have very low densities, do not show Tm or measurable crystallinity and have molecular weights ranging from 80 × 103 to 290 × 103 g · mol−1.
19.
Dominika B. Bernert Kathrin Isenbügel Helmut Ritter 《Macromolecular rapid communications》2011,32(4):397-403
A synthetic model glycoprotein was successfully synthesized using gelatin and mono‐6‐para‐toluenesulfonyl‐β‐cyclodextrin which were reacted under microwave conditions in basic media. The resulting glycoprotein is observed to form intermolecular inclusion complexes through complexation of the aromatic moieties along the polymer chain by the attached cyclodextrins. This phenomenon was analyzed and proven by 2D NMR spectroscopy (ROESY) and dynamic light scattering (DLS). Above the denaturation temperature, a strong increase of the hydrodynamic diameter was found due to enhanced supramolecular agglomeration. Such a novel glycoprotein with supramolecular self‐recognition would be promising in biomedical applications serving as a drug‐delivery basis polymer.
20.
Densities and viscosities of a series of blends of poly(ethylene glycol) (PEG) and poly(ethylene glycol‐ran‐propylene glycol) (PEG‐ran‐PPG) were measured at a temperature above the melting point. The density and viscosity data were fitted with analytical functions involving the volume fraction of PEG, ϕPEG. Stress relaxation curves for the pure components and blends were obtained through Monte Carlo (MC) simulations. A typical stress relaxation curve exhibits a fast mode that represents energetic‐interactions‐driven motion and a slow mode that originates from the entropy‐driven motion. Flory–Huggins interaction parameters (χ) for the blends are much smaller than the critical values (χcritical). The calculation of χ and χcritical provides important clues for polymer blend processing.