Search

A one-pot “grafting-from” strategy is presented to prepare AB- and ABA-type bottlebrush block copolymers (BBCPs). Precursor block copolymers with pendant dithiocarbamate and hydroxyl groups were synthesized as the macroinitators. Polylactide (PLA) and poly(N-vinylpyrrolidone) (PVP) side chains were grafted by ring-opening polymerization (ROP) and reversible addition-fragmentation chain-transfer (RAFT) polymerization in one pot, respectively. Molecular weight control was achieved as evidenced by gel permeation chromatography (GPC) and 1H nuclear magnetic resonance (1H NMR). The length of side chains in each block (DP from 8 to 113) could be facilely tuned by polymerization conditions such as the reaction time and the feed ratio of monomer to initiator, leading to various molecular morphologies observed by atomic force microscopy (AFM). This synthetic strategy is flexible and adaptable, allowing convenient access to customized macromolecular architecture.

While the metallocene polymers were comprehensively studied, other metallopolymers are rarely explored. The major challenge is the lack of a synthetic platform for the preparation of metal coordinated derivatives, monomers, and polymers. Therefore, the development of a facile synthesis of new metal coordinated monomers and polymers is critically needed. A novel successfully synthesized methacrylate-containing nickel complex is reported in this communication. Controlled RAFT polymerizations are further carried out to prepare a series of side-chain nickel containing polymers with different molecular weight and narrow Polydispersity Index (PDI). This new metallopolymer performs specific electrochemical and excellent thermal properties. This study provides a novel and convenient strategy to prepare metallopolymer with controllable molecular weight, which has potential applications in assembled, catalytic and magnetic materials.

Metal coordinated micelles based on the diblock copolymer PHEMA82-b-HQ78 were synthesized. The block PHQ with 8-hydroxyquinoline groups can coordinate with metal ions to form the crosslinked core for micellization, while the other block PHEMA in the shell of the micelle improves its solubility. The morphological characteristics and the coordinating interaction between the metal ions and the core segment were characterized by DLS and TEM. The magnetic measurement found that the Curie-Weiss temperature Tθ of the metalized micelle was 56 K and its hysteresis loop exhibited the typical ‘S’ shape with low Hc and Mr at 5 K, indicating that this micelle had the properties of soft ferromagnetic materials.

Adding β-nucleating agents (β-NAs) has been generally considered as an effective approach to induce the formation of β-crystals in propylene-ethylene random copolymer (PPR). However, it is still difficult to obtain the expected percentage of β-crystal under normal processing conditions, due to the temperature control is always a key factor no matter with or without adding β-NAs. We assumed that simultaneously adding both α- and β-NAs to PPR in rational ratios would facilitate the growth of β-crystal. The effects of adding various amount of α- and/or β-NAs on the α- and β-crystallization behavior and morphology were investigated. More importantly, the influence of temperature control on inducing β-crystal in the presence of different NAs was parallel explored by utilizing sample bars prepared via injection molding and sample pipes produced from a typical industrial extrusion line. Different crystallization situations were carefully discussed in response to various nonisothermal crystallization processes in laboratory experiments and in actual pipes extrusion. At last, the mechanical properties of PPR samples were examined to provide new clues for further study of PPR pipes. POLYM. ENG. SCI., 2016. © 2016 Society of Plastics Engineers

Homopolymer (PBIP) containing 2,6-bis(1′-methylbenzimidazolyl)pyridine (MeBIP) ligands in the side chain was synthesized by RAFT polymerization and its kinetics was studied. Polymeric complex PBIP-Nd3+ was prepared by chelating PBIP with lanthanide ion Nd3+. The homopolymers and PBIP-Nd3+ complex were investigated by NMR, FTIR, GPC and TGA. The optical property of PBIP-Nd3+ complex was characterized by UV-Vis spectroscopy. The magnetic property of PBIP-Nd3+ complex was measured as a function of temperature (5 K to 300 K) and as a function of field (−3.98 × 106 A/m to 3.98 × 106 A/m). These results indicated that PBIP-Nd3+ complex is paramagnetic.

Two polymers containing pyridine rings were prepared by free-radical polymerization and confirmed by Fourier transform infrared and 1H NMR spectra. The preparation of four multilayer films that were obtained by self-assembly of the polymer and the transition metal neutralized polyelectrolyte on PE substrate was described. UV–vis spectra and atomic force microscopy images were applied to characterize these films and indicate the uniform assembling process. The driving force for building up the multilayer films was identified by infrared spectroscopy to be the coordination interaction. The magnetic behavior was examined as a function of magnetic field strength at 30 kOe and as a function of temperature (5–300 K). All films display strong soft ferromagnetic properties and higher than those of the bulk materials. The magnetic results show that the layer-by-layer self-assembling approach is beneficial to the ordered alignment of adjacent paramagnetic spins and induces better magnetic phenomena. Copyright © 2015 John Wiley & Sons, Ltd.

L-lactide (LLA) homopolymerization and copolymerization with ɛ-caprolactone (CL) in toluene initiated by tetrahydrosalen-supported yttrium borohydride complex were systematically investigated. A possible mechanism of LLA homopolymerization was proposed according to the 1H-NMR result. In addition, PCL-b-PLLA copolymers were synthesized by sequential addition of monomers and their structure was characterized by GPC, 1H-NMR and 13C-NMR.

The poly(2,2-dimethyltrimethylene carbonate) (PDTC) with one hydroxyl and one formate terminal functions was synthesized by in situ generated, tetrahydrosalen stabilized yttrium borohydride complex. The influences of monomer/initiator molar ratio, temperature and reaction time on polymerization of DTC were investigated. Under the condition: [DTC]/[I] = 500, 55°C, toluene: 0.5 mL, DTC: 0.6 g, PDTC with Mn = 15600 and PDI = 2.15 was obtained. Through 1H-NMR and 13C-NMR analyses, the structure of PDTC was characterized and a coordination-insertion mechanism was proposed. In addition, the random copolymerization of DTC and caprolactone (CL) initiated by rare-earth borohydride compound was studied. The microstructure of PDTC-co-PCL includes four diads: DTC-CL, CL-CL, DTC-DTC and CLDTC, which were determined by the specific signals in 1H-NMR spectra. Based on the typical signals of the formate (δ=8.08) and hydroxyl (δ = 3.34) end groups of PDTC-co-PCL, a mechanism involving DTC monomer inserts before CL during the initiation process was presumed. Furthermore, the thermal properties of amorphous copolymer were characterized by differential scanning calorimetry (DSC). The results support the random structure of PDTC-co-PCL.

The biphenol based discrete ion-pair rare earth complexes, [Ln(EDBP)2(DME)Na(DME)3] [Ln = Er(1), Yb(2), Sm(3)], were prepared and used as catalysts for the ring-opening polymerization (ROP) of 2,2-dimethyltrimethylene carbonate (DTC). Three complexes show moderate activities for the polymerization, and the catalytic activities increase in the following sequence: (Yb < Er < Sm). The effect of different ratios of [DTC]/[Ln], polymerization temperature and time on the polymerization was investigated. Moreover, PDTC without ether unit developed from possible CO2 elimination was prepared.

Ring-opening polymerization of 1-methyltrimethylene carbonate (MTMC) initiated by highly active single-component rare earth tris(2,6-di-tert-butyl-4-methylphenolate)s [Ln(OAr)3, Ln = La, Dy, Y] or yttrium isopropoxide [Y(OiPr)3] is reported for the first time. PolyMTMC (Mw = 8.4 × 104, molecular weight distributions = 1.5) initiated by La(OAr)3 at [MTMC]/[initiator] = 1000 was obtained with the yield over 99% in toluene within 1 h at 30 °C. Random and block copolymers of MTMC with e-caprolactone (CL), 2,2-dimethyltrimethylene carbonate (DTC) or polyethylene glycol (PEG) including poly(MTMC-r-CL), poly(MTMC-b-CL), poly(MTMC-r-DTC), poly(MTMC-b-DTC), and poly(MTMC-b-PEG-b-MTMC) were synthesized. The differential scanning calorimetry results show that thermal behaviors of the polymers sensitively depend on their compositions and chain structures. Furthermore, the measurements of 1H-1H COSY and density functional theory calculation are applied to investigate the mechanism. The polymerization of MTMC takes place according to a coordination-insertion mechanism, and the ring is opened via acyl-oxygen bond cleavage resulting in a LnO active center. There exist two ring-opening modes of MTMC in which mode b, breaking the CH2OCO bond, is the major pathway. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3807–3815, 2010

End-capped poly(e-caprolactone)s (PCLs) have been prepared elsewhere by various initiators. However, hydroxytelechelic PCLs have been reported less frequently, although there are two hydroxyl end groups in one polymer chain, which allows diversified functionalization. Two tetrahydrosalen-backboned chlorides containing rare-earth complexes, YbLCl(DME)2 and ErLCl(DME) {where L is 6,6′-[ethane-1,2-diylbis(methylazanediyl)]bis (methylene)bis(2,4-di-tert-butylphenol) and DME is dimethoxyethane}, were first synthesized in this study, and they were used as initiator precursors for a ring-opening polymerization in the presence of NaBH4 to afford hydroxytelechelic PCLs. The polymerization under different conditions was investigated, and a possible mechanism is proposed. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

The free radical copolymerization of three N -phenylmaleimides bearing a chiral oxazoline residue at ortho -position of the phenyl group (OPMI) with methyl methacrylate (MMA) was carried out in tetrahydrofuran by varying the molar ratio of the comonomers. The monomer reactivity ratios and Alfrey–Price Q – e values were determined. The data revealed that the monomer OPMI has a distinct tendency to cross-propagate and MMA is inclined to block formation. Meanwhile, the MMA co-units affected significantly the chiroptical property of resulted copolymers besides endowing them with a moderate film-forming ability. Poly(OPMI- co -MMA)s coated on macroporous silica were used as a high-performance liquid chromatography chiral selector, and the optical resolution performance was briefly evaluated toward some racemic compounds including amino- and hydroxy-acids as well as 1,1′-bi-2-naphthol. The observation indicated that the column combining MeOPMI/MMA copolymers with higher chiral component exhibits an extent of enantioselectivity in both normal and reversed-phase modes.

A novel fully conjugated polymer containing 1,10-phenanthroline (DAPcDOD) was first synthesized by the polycondensation of 2,7-dimethyl-2,4,6-octatriene-1,8-dial with 5,6-diamine-1,10-phenanthroline. Three polymeric complexes were first prepared by the reaction of DAPcDOD with NiSO4, CoCl2, and FeSO4, respectively. The structures of the polymer and the complexes were characterized by IR, 1H-NMR, and elemental analysis. The magnetic behaviors of these complexes were measured as a function of magnetic field strength (0–50 kOe) at 5 K and as a function of temperature (5–300 K) at a magnetic field strength of 30 kOe. The results show that DAPcDOD–Ni2+ and DAPcDOD–Co2+ were soft ferromagnets, whereas DAPcDOD–Fe2+ exhibited the features of an antiferromagnet. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

The preparation and magnetism of two supramolecular polymeric complexes, DABT/PAA-Ni2+ and DABT/PAA-Cu2+, which were obtained via electrostatic interactions of 2,2′-diamino-4,4′-bithiazole (DABT), poly(acrylic acid) (PAA), and transition metal ions (Cu2+ or Ni2+) were described. FTIR, 1H NMR, and elemental analysis were used to characterize the structures of the obtained supramolecular polymer and the corresponding complexes. The corresponding multilayer films were also constructed on the quartz substrate. UV–vis spectra and AFM images were applied to characterize these films. The result indicates a process of uniform assembling. The magnetic behavior was examined as a function of magnetic field strength at 4 K and as a function of temperature (4–300 K). It was found that DABT/PAA-Ni2+ exhibits a ferromagnetic property with a high value of relative saturation magnetization, while DABT/PAA-Cu2+ shows a special magnetic property different from the typical magnet. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

Two comb-like copolymers (BIMT and PMB) composed of N-2-thiazolylmethacrylamide (NTMA) and 2-(1-butylimidazolium-3-yl) ethyl methacrylate tetrafluoroborate (BIMA) were prepared by free radical polymerization and reversible addition-fragmentation chain transfer (RAFT) polymerization. The conversion of the monomers to copolymer has been confirmed by FTIR spectra and 1H NMR spectra. The metal (Ni2+, Nd3+) complexes of these two copolymers were prepared, and the magnetic behaviors of the complexes were studied. The coordinated complexes display three possible chelating structures, which lie on the nitrogen donor and oxygen donor ligands and the kinds of the metal ions. The bimetallic complexes (BIMT-Nd-Ni and PMB-Nd-Ni) were synthesized by using the different coordination sites of the polymers. The magnetic properties of the complexes show that different structures arising from the different preparations, the kinds and the contents of metal ions, and the state of the complexes can infect the exchange interaction between the metal ions and induce various magnetic phenomena. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 5123–5132, 2008

N-Phenylmaleimide derivatives bearing a chiral oxazoline substituent at the benzene ring (N-[o-(4,5-dihydro-1,3-oxazol-2-yl)phenyl]maleimides, OPMIs) were polymerized using a binary initiating system composed of Et2Zn and n-BuLi to in situ produce the zinc complexes of optically active poly(OPMI)s. The significant changes in chiroptical and fluorescent properties were observed for these polymers upon complexation with metal ions due to the formation of supramolecular structure, evidenced by circular dichroism, fluorescence spectrum and atomic force microscopy. The fluorescence spectra of poly(OPMI)/ZnII complexes in the presence of (R)/(S)-1,1′-bi-2-naphthol (BINOL) and (R)/(S)-2-amino-1-propanol were studied in THF media. It was found that the fluorescence intensity of the complexes responded differently to both enantiomers of BINOL and the amino alcohol in a quenching and enhancement fashion, respectively. Furthermore, the enantioselective fluorescence response was strongly dependent on the amount of incorporated zinc in polymer matrices.

Poly(e-caprolactone)s (PCLs) with various end-capping groups were prepared upon the novel one-pot reduction–initiation strategy. The reduction-involved ring-opening polymerization developed by Guillaume et al. has been firstly extended to aldehydes and ketones. The carbonyl compound was reduced by lanthanide borohydride (Nd or Y) to intermediate, which in situ triggered the ring-opening polymerization of e-caprolactone. This one-pot strategy affords an efficient access to prepare the end-capped polymers from aldehydes or ketones. The reduction–initiation process and polymers were characterized by IR, NMR and SEC, and the possible mechanism was proposed.

A series of optically active amphiphilic block copolymers were synthesizedby using potassium alkoxide of poly(ethylene glycol) monomethyl ether (MeOPEGO−K+) to initiate the anionic polymerization of N-{o-(4-phenyl-4,5-dihydro-1,3-oxazol-2-yl)phenyl}maleimide [(R)-PhOPMI]. The PEG-macroinitiators generated in situ in the reaction between MeOPEGOH and potassium naphthylide in tetrahydrofuran. The synthetic procedure may provide the PEG-b-PPhOPMI copolymers with well-defined structure, as evidenced by gel permeation chromatography, 1H NMR, FTIR, and elemental analysis. In particular, the preparation of block copolymers having a laevorotation or dextrorotation activity was accomplished by changing the feed composition. The micellization was examined for the amphiphilic block copolymers in aqueous milieu by fluorescence spectroscopy, dynamic light scattering, and circular dichroism. The results indicate that the copolymers could form regular spherical micelles with core-shell structure when the hydrophilic component was long enough; in contrast, the copolymers containing shorter PEG segments formed aggregates in large dimension due to the considerable interaction between hydrophobic PPhOPMI components. Also, it was found that the aggregated structure of the polymeric micelles is strongly dependent on the medium nature and the polymer concentration. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1025–1033, 2008

A new polyamide containing bithiazole moieties (polythiazole amides, PTA) was synthesized by the polycondensation of 2,2′-diamino-4,4′-bithiazole and oxalyl chloride. The rare-earth metal complexes of the polymer were prepared from PTA and rare-earth chloride in DMSO. The structures of the polymer and the complexes were characterized through IR spectra. The preliminary magnetic properties of the complexes were investigated; it was found that these materials are ferromagnets at low temperature. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

Imidazolium salts, most of which are room temperature ionic liquids (ILs), have been introduced as effective and tunable cocatalysts in the copolymerization of CO 2 with epoxides catalyzed by (salen)Cr III Cl complex for the first time. Effects of imidazolium salts with different alkyl chains as well as with different anions on the copolymerization were investigated. The results showed that the copolymerization was influenced obviously by the property of anion. In addition, the cation of imidazolium salts with longer alkyl chain length such as n -dodecyl (TOF, 242.5 h −1 , carbonate linkages > 99%) displays better activities and selectivity in the copolymerization as compared with N -MeIm (TOF, 72.5 h −1 , carbonate linkages 94%). These results are instructive for further design of task-specific ILs as effective cocatalysts to improve the copolymerization of CO 2 with epoxides.

A novel linear polymer (PFABT) containing bithiazole rings was synthesized by polycondensation of 2,2′-diamino-4,4′-bithiazole (DABT) and formaldehyde. The complexes of PFABT with two transition metal ions (Fe2+, Cu2+) were prepared for the first time. The polymer was determined through FT-IR, 1H-NMR and elemental analysis (EA), and the complexes were characterized by FT-IR. The magnetic behaviors of these complexes were measured as a function of magnetic field strength (0–50 kOe) at 4 K and as a function of temperature (4–300 K) under an applied magnetic field of 30 kOe. The results show that PFABT-Cu2+ is a ferromagnet while PFABT-Fe2+ is an anti-ferromagnet. Copyright © 2007 John Wiley & Sons, Ltd.

Two N-phenylmaleimide derivatives bearing a chiral oxazoline group, N-[o-(4-phenyl-4,5-dihydro-1,3-oxazol-2-yl)phenyl]maleimide [(R)-PhOPMI] and N-[o-(4-isopropyl-4,5-dihydro-1,3-oxazol-2-yl)phenyl]maleimide [(S)-PriOPMI], were polymerized using in situ generated calixarene-based phenates as initiators to yield optically active polymers. The formation of star-shaped architectures was strongly dependent on both polymerization conditions and calixarene moieties. In the case of polymerization conducted in toluene at 80–100 °C, the arm-chain numbers achieved their respective maxima for the polymers with these multifunctional initiators. In contrast, the polymers obtained in polymerizations at lower temperature possessed fewer arm chains. The structure and chiroptical properties were investigated on the basis of 13C NMR, multiangular laser light scattering, gel permeation chromatography, and circular dichroism for the macromolecules with calixarene cores. Copyright © 2006 Society of Chemical Industry

Two novel copolymers containing bithiazole rings and ethylene oxide on the skeleton (PPOBTz and PNOBTz) were synthesized via Schiff reaction and Ullmann reaction, respectively. The copolymers were characterized by FTIR, 1H NMR. Their polymeric complexes with Cu2+ and Nd2+ were prepared. The magnetic behavior of these polymeric complexes was measured as a function of magnetic field strength (0–60 kOe) at 4 K and as a function of temperature (4–300 K) at a magnetic field strength of 30 kOe, indicating that they all exhibited features of soft ferromagnet.

The polymer (DAPcTPA) was synthesized by polycondensation of 5,6-diamine-1,10-phenanthroline (DAP) with terephthaldehyde (TPA). Three polymeric complexes were first prepared from polymer (DAPcTPA) and NiSO 4 , CoCl 2 or FeSO 4 , respectively. The structures of polymer and complexes were characterized by IR, 1 H NMR spectra and elemental analysis. The magnetic behavior of these complexes was measured as a function of magnetic field strength (0–50 kOe) at 5 K and as a function of temperature (5–300 K) at a magnetic field strength of 30 kOe. The results show that DAPcTPA-Ni 2+ and DAPcTPA-Co 2+ are soft ferromagnets, while DAPcTPA-Fe 2+ exhibits features of an antiferromagnet.

N-2-Thiazolylmethacrylamide (NTMA) was polymerized by a radical route to obtain the polymer in good yields. The complexes of PolyNTMA with three rare earth ions Nd(III), Pr(III), and Sm(III) were prepared for the first time. FTIR and 1H NMR were applied to characterize these materials. The magnetic behavior of PolyNTMA–metal complexes was examined as a function of applied magnetic field at 4 K and as a function of temperature (4–300 K) at an applied magnetic field of 30 kOe. It was found that Pr(III) complex exhibits an antiferromagnetic property, while Nd(III) and Sm(III) complexes exhibit a special magnetic property different from the typical magnet. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1289–1293, 2006

Interpenetrating polymer networks (IPNs) composed of silk sericin (SS) and poly(N-isopropylacrylamide) (PNIPAAm) were prepared simultaneously. The properties of the resultant IPN hydrogels were characterized by differential scanning calorimetry and SEM as well as their swelling behavior at various temperatures and pH values. The single glass transition temperature (Tg) presented in the IPN thermograms indicated that SS and PNIPAAm form a miscible pair. The swollen morphology of the IPNs observed by SEM demonstrated that water channels (pores present in SEM micrographs) were distributed homogeneously through out the network membranes. The swelling ratio of the IPNs depended significantly on the composition, temperature and pH of the buffer solutions. The dynamic transport of water into the IPN membrane was analyzed based on the Fickian equation. Copyright © 2006 Society of Chemical Industry

An in situ–generated tetrafunctional samarium enolate from the reduction of 1,1,1,1-tetra(2-bromoisobutyryloxymethyl)methane with divalent samarium complexes [Sm(PPh2)2 and SmI2] in tetrahydrofuran has proven to initiate the ring-opening polymerization of ϵ-caprolactone (CL) giving star-shaped aliphatic polyesters. The polymerization proceeded with quantitative conversions at room temperature in 2 h and exhibited good controllability of the molecular weight of polymer. The resulting four-armed poly(ϵ-caprolactone) (PCL) was fractionated, and the dilute-solution properties of the fractions were studied in tetrahydrofuran and toluene at 30°C. The Mark–Houwink relations for these solvents were [η] = 2.73 × 10−2Mw0.74 and [η] = 1.97 × 10−2Mw0.75, respectively. In addition, the unperturbed dimensions of the star-shaped PCL systems were also evaluated, and a significant solvent effect was observed. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 175–182, 2006

A new methacrylic monomer, 4-(2-thiazolylazo)phenylmethacrylate (TPMA) was synthesized. Copolymerization of the monomer with methyl methacrylate (MMA) was carried out by free radical polymerization in THF solution at 70 ± 0.5°C, using azobisisobutyronitrile (AIBN) as an initiator. The monomer TPMA and the copolymer poly(TPMA-co-MMA) were characterized by Fourier transform infrared (FTIR), 1 H nuclear magnetic resonance (NMR), and elemental analysis methods. The polydispersity index of the copolymer was determined using gel permeation chromatography (GPC). Thermogravimetric analysis (TGA) of the copolymer performed in nitrogen revealed that the copolymer was stable to 270°C. The glass transition temperature (T g ) of the copolymer was higher than that of PMMA. The copolymer with a pendent aromatic heterocyclic group can be dissolved in common organic solvents and shows a good film-forming ability. Both the monomer TPMA and the copolymer poly (TPMA-co-MMA) have bright colors: orange and yellow, respectively.

A novel polymer (poly[2,2'-(4,4'-bithiazolylene)][N-(2-ethylhexyl)-3,6-carbazylene] (PBTCA) was first synthesized from 2,2′-diamino-4,4′-bithiazole and N-(2-ethylhexyl)-3,6-diformylcarbazole. The structure of the polymer was determined with IR and 1H-NMR spectroscopy. The PBTCA–Nd3+ complex was prepared via the mixing of neodymium trichloride hexahydrate and PBTCA in dimethyl sulfoxide under a nitrogen atmosphere. The magnetic behaviors of the Nd3+ complex of a poly(Schiff base) were measured as a function of the magnetic field strength (0–50 kOe) at 4 K and as a function of the temperature (4–300 K). The results show that PBTCA–Nd3+ is a ferromagnet when the temperature is below 15 K, and above that, it is a diamagnet. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 443–446, 2006

Ammonium-based ionic liquid monomers and their corresponding polymers [poly(ionic liquid)s] are synthesized and characterized for CO2 sorption. The polymers have much higher CO2 sorption capacities than the room-temperature ionic liquids and imidazolium-based poly(ionic liquid)s. For example, P[VBTMA][PF6] with polystyrene backbone has a CO2 sorption capacity of 10.67 mol%. The CO2 sorption is selective over N2 and O2. The effects of cation, backbone, substituent, anion and crosslinking on CO2 sorption are discussed. The sorption mechanism study indicates that CO2 sorption by the poly(ionic liquid)s is a bulk and surface phenomenon.

Anionic polymerizations of chiral N -phenylmaleimide derivatives bearing an oxazoline pendant (OPMI) were carried out with n -BuLi initiator to obtain optically active polymers. The polymer yields and specific optical rotations ( [ α ] D 25 ) were found to be significantly influenced by the reaction solvent, temperature, and the molar ratio of initiator to monomer. Particularly, the specific optical rotations exhibited a linear dependence on the molecular weights for the formed polymers, and the inversion from levo- to dextro-specific rotation was also observed with an increase in the molecular weights. On the basis of the results from circular dichroism (CD) and 13 C NMR spectral analyses, the optical activity of poly(OPMI)s was attributed not only to the chirality of oxazolinyl groups in monomeric units but also to the partial helical structure due to an excess of threo-diisotactic configuration in the main chain.

Two novel poly(Schiff base)s (PPHBT and PPHPHN) were prepared by polycondensation of 2,2′-diamino-4,4′-bithiazole (DABT), 5,6-diamino-1,10-phenanthroline (DAPH) with bisdecyloxyterephthaldehyde (BDTA), respectively. The structures of the poly(Schiff base)s were determined by IR and 1H NMR spectroscopy. The Nd3+ complexes of poly(Schiff base) were prepared and characterized. The contents of Nd for complexes were measured by complexometric titration. The magnetic behavior of the complexes was examined as a function of magnetic field strength at 4 K and as a function of temperature (4–300 K). The results show that both PPHBT-Nd3+ and PPHPHN-Nd3+ exhibit the characteristic of soft-magnetic materials at low temperature.

Copolymers of poly(ethylene oxide) (PEO) and 5,5'-azodisalicylic acid (Olsalazine, OLZ) were synthesized and evaluated by hydrolysis and in-vitro biodegradation with azoreductase. It was found that changing the molecular weight of the PEO blocks affected the loading ratio of OLZ, and resulted in significant differences in the hydration and degradability of the copolymers. These novel azo-containing copolymers can be used in colon-specific drug delivery.

Two novel fully conjugated polymers containing bithiazole rings (PDDBTz and PDABTz) were first synthesized by polycondensation of 2,7-dimethyl-2,4,6-octatriene-1,8-dial with 2,2′-bis(diethylphosphinatyl methyl)-4,4′-bithizole or 2,2′-diamino-4,4′-bithiazole (DABT). The structure of the polymers was determined by IR, 1H NMR and elemental analysis. PDDBTz is soluble in trifluoroacetic acid and DMSO, whereas PDABTz is soluble in common solvent such as THF, DMSO, DMF. Bithiazole rings were introduced to provide bidentate N-donor sites for binding metal ions. Their lanthanide metal complexes were prepared. The magnetic behavior of these polymeric complexes was measured as a function of magnetic field strength (0–60 kOe) at 4 K and as a function of temperature (4–300 K) at magnetic field strength of 30 kOe. The results show that they all exhibit features of soft ferromagnet.

A novel polymer resulting from the polycondensation of 2,2′-diamino-4,4′-bithiazole (DABT) with 5,5′-methylene-bis-salicylaldehyde (MBSA) and its ferric complex are described. Analyses of Fourier transform infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS) revealed that both bithiazole residue and Schiff-base moiety acted as coordination sites for Fe3+ ions in the polymeric matrix. The magnetic behavior of the complex was studied as a function of magnetic field strength (0–60 kOe) at 25 K and as a function of temperature (5–300 K) at a magnetic field strength of 30 kOe. The hysteretic loop was measured at 5 K for the complex showing coercivity (Hc) of 20 Oe and remnant magnetization (Mr) of 0.002 emu/g, which is much lower than those of bithiazole-based polymeric complexes previously reported. The results indicated that the present complex is of the typical characteristics of a soft ferromagnet. Copyright © 2005 John Wiley & Sons, Ltd.

The ring-opening polymerization of e-caprolactone initiated with a divalent samarium bis(phosphido) complex [Sm(PPh2)2] is reported. The polymerization proceeded under mild reaction conditions and resulted in polyesters with number-average molecular weights of 8.2 × 103 to 12.5 × 103. The yield and molecular weight of poly(e-caprolactone)s were dependent on the experimental parameters, such as the monomer/initiator molar ratio, the monomer concentration, the reaction temperature, and the polymerization time. The obtained polymers were characterized with Fourier transform infrared, NMR, gel permeation chromatography, and differential scanning calorimetry. On the basis of an end-group analysis of low-molecular-weight polymers by NMR spectroscopy, a coordination–insertion mechanism is proposed for the polymerization. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1558–1564, 2005

A series of imidazolium-based ionic liquid monomers and their corresponding polymers (poly(ionic liquid)s) were synthesized, and their CO2 sorption was studied. The poly(ionic liquid)s had enhanced CO2 sorption capacities and fast sorption/desorption rates compared with room temperature ionic liquids. The effects of the chemical structures, including the types of anion, cation, and backbone of the poly(ionic liquid)s on their CO2 sorption have been discussed. In contrast to room temperature ionic liquids, the polymer with PF anions had the highest CO2-sorption capacity, while those with BF or Tf2N− anions had the same capacities. The CO2 sorption and desorption of the polymers were fast and reversible, and the sorption was selective over H2, N2, and O2. The measured Henry's constants of P[VBBI][BF4] and P[MABI][BF4] were 26.0 bar and 37.7 bar, which were lower than those of similar room temperature ionic liquids. The preliminary study of the mechanism indicated that the CO2 sorption of the polymer particles was more absorption (the bulk) but less adsorption (the surface). © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5477–5489, 2005

The polymerization of N-phenylmaleimide was carried out with the binary rare-earth coordination catalyst lanthanum phosphonate [La(P507)]–trisobutyl aluminum [Al(i-Bu)3] in toluene at 60°C. The dependence of the polymerization on the polymerization time, the molar ratio of Al(i-Bu)3 to La(P507), and the concentration of the catalyst were studied. The structures of the resultant polymer were characterized with 1H-NMR, 13C-NMR, and Fourier transform infrared spectrophotometry, and the thermal properties of the polymer were measured with thermogravimetric analysis. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 979–982, 2005

N-2-thiazolyl(meth)acrylamides were poly- merized by a radical route to obtain polymers in good yields. The polymers, with a pendent heterocyclic group, are soluble in common organic solvents, which allow the corre- sponding metal complexes with higher loads to be prepared easily. FTIR, 1 H NMR, and energy-dispersive X-Ray spec- troscopy (EDX) were applied to characterize these materials. The magnetic behavior of poly(N-2-thiazolyl(meth)acrylam

The synthesis of π-conjugated poly(thiazole-2,4-diyl) (PTz) and its complexes incorporating lanthanide ions in the main chain (PTz–Nd 3+ , PTz–Gd 3+ ) is described for the first time. FT-IR, 1 H NMR, and elemental analysis were used to study the structure of the obtained materials. The magnetic properties of the polymeric complexes were measured as a function of temperature (3–300 K) under an applied magnetic field of 30 kOe, and the results indicated that there are ferromagnetic interactions between the metal ions. The complexes PTz–Nd 3+ and PTz–Gd 3+ have the Curie–Weiss temperature of 254 and 28 K, respectively. Both polymeric complexes exhibited a hysteresis loop at 5 K, the coercive field and remanence magnetization is, respectively, 51.4 Oe and 0.0033 emu/g for PTz–Nd 3+ ; while corresponding values are 26.1 Oe and 0.018 emu/g for gadolinium complex.

A series of novel polyimide and poly(Schiff base) oligomers containing substituted bithiazole rings were designed and synthesized, for the first time, by polycondensation of 5,5 ′ -dimethyl-2,2 ′ - diamino-4,4 ′ -bithiazole (MDABT) with dianhydrides (pyromellitic dianhydride, 3,3 ′ -4,4 ′ -benzophenone tetracarboxylic dianhydride and bis (3,4-dicarboxyphenyl) ether dianhydride), and dialdehydes (oxalic aldehyde, isophthalaldehyde and terephthalaldehyde). The structure of the oligomers was determined by IR and 1 H NMR spectroscopy, and elemental analysis. The oligomers showed good thermal stability. The Fe 2+ complex of poly(Schiff base), synthesized from MDABT with oxalic aldehyde (PMTOA), was prepared with 13.7% Fe content and found to be a ferromagnet at low temperature.

Two novel bithiazole-containing poly-amides, DClAI and DTTPA, and their complexes were syn-thesized by condensation and complexation. Novel homo-geneous composite films were prepared by in situ blendingthese complexes with polyvinyl alcohol. These polymericcomplexes and composite films were characterized by FTIR.The magnetic properties of the complex and its related com-posite film were measured using a physical property mea-surement system. It was found that the properties of filmsare similar to those of their related polymeric complexes. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1264–1270, 2004 Key words: polyamides; synthesis; blending; compositefilms; magnetic polymers INTRODUCTION In recent years, there has been considerable interest inorganic ferromagnets. 1–4 Organic or polymeric ferro-magnetics are a new kind of magnetic materials andfrequently appear in the scientific literature. 5–7 Com-pared with inorganic ferromagnetics, the organic fer-romagnetics exhibit characteristics of structural diver-sities, low density, and ready processing.

This paper describes the synthesis of a novel heterocyclic polymer incorporating both bithiazole and tetrathiapentalene moieties in the main chain. The complexion of the polymer with FeSO 4 or NdCl 3 in dimethyl sulfoxide produced corresponding metal complexes. Based on IR spectra and X-ray photoelectron spectroscopy (XPS) data the structure of these metal complexes is discussed briefly. The magnetic properties of the metallopolymers were measured as a function of magnetic field strength (0–60 kOe) at 5 K and as a function of temperature (5–300 K) under an applied magnetic field of 30 kOe, respectively. The neodymium complex exhibits a hysteresis cycle at 5 K, the observed coercivity H c and the remnant magnetization M r are 15 Oe and 0.00035 emu/g, respectively.

The paper presents the polymerization of acrylonitrile (AN) initiated by samarium diiodide (SmI 2 ) combining with hexamethylphosphoramide (HMPA) for the first time. The effects of various parameters, such as reaction temperature, AN/Sm and HMPA/Sm molar ratios, reaction time on the polymer yield and its molecular weight were discussed. On the basis of both IR and NMR analysis of resulted polymers, a single-electron-transfer initiation mechanism of AN as radical anion was proposed for this polymerization, which was further sustained by the copolymerization of AN with e-caprolactone and 2,2-dimethyltrimethylene carbonate, respectively.

Divalent samarium bis(phosphido) complex Sm(PPh2)2 was first applied as an initiator for the ring-opening polymerization of e-caprolactone (e-CL). In comparison to samarium diiodide (SmI2), this Sm(II) complex exhibited much higher activity and yielded poly(e-CL) with higher molecular weight. At the same time, an in-situ generated tetrafunctional samarium enolate from the reduction of 1,1,1,1-tetra(2-bromoisobutyryloxymethyl)methane with Sm(PPh2)2 or SmI2 has proven to initiate the polymerization of e-CL under mild conditions. The resulting linear and star-shaped poly(e-CL)s have been characterized by 1H NMR, GPC, and SLS.

The copolymerization of N -phenylmaleimide (NPMI) with styrene (St) was studied with a rare earth coordination catalyst Nd(naph) 3 –AlEt 3 in toluene at 50 °C. The compositions of the two monomers in copolymers were close to 1:1 even at a high monomer conversion of about 60%, and did not change as the NPMI feed mole fraction varied from 10% to 90%. The copolymer was characterized by 13 C nuclear magnetic resonance spectroscopy, showing that the copolymer possessed a nearly alternating structure. The thermal properties of the copolymers were also investigated. It was presumed that a charge transfer complex of NPMI and St participated in the polymerization process.

A novel bithiazole oligomer (PCBT) was synthesized from C60 and the diazo salt of 2,2′-diamino-4,4′-bithiazole (DABT). Its ferro-complex (PCBT-Fe2+) was prepared from PCBT and FeSO4 in DMSO solution under a purified nitrogen atmosphere. The magnetic behavior of PCBT and PCBT-Fe2+ was measured as a function of magnetic field strength (0–60 kOe) at 5 K and as a function of temperature (5–300 K) at a magnetic field strength of 30 kOe. PCBT-Fe2+ complex exhibits a hysteresis cycle at 5 K, the observed coercive field (HC) and remnant magnetization (Mr) are 690 Oe and 0.12 emu/g, respectively. The results show that PCBT is an anti-ferromagnet and its Fe2+-complex is a soft ferromagnet.