Oxygen-Exchange Reaction Between Artificial Lung Device: The Heme Embedded in Polymerized Lipo Liposome as an Artificial Oxygen Carrier

An oxygen-supplying medium (OSM), which was prepared by embedding a synthetic heme complex in a bilayer of polymerized lipid liposome (polylipid liposome/heme), could bind molecular oxygen reversibly under physiological conditions. The oxygen-exchange reaction of OSM with blood was examined by using a liquid/liquid artificial lung device. For example, deoxy-blood (p _s(O₂) = 0 torr) was passed countercurrent to oxy-OSM (p _s(O₂) = 154 torr) through hollow fibers of the device to provide oxy-blood (p _b(O₂) = 57 torr). The OSM was physicochemically and mechanically stable under strong shear stress during the passage through the hollow fibers and acted as the oxygen mediator to blood.     

Liposome formation of selectively-polymerized diene-containing phospholipids and their postpolymerization

Small and large unilamellar liposomes composed of 1,2-bis(2,4-octadecadienoyl)-sn-glycero-3-phosphorylcholine (DODPC) are prepared by sonication and extrusion, respectively. They are polymerized with water-insoluble radical initiator, azobis(isobutyronitrile) (AIBN) which can selectively polymerize diene groups in 1-acyl chains of the lipids. Polymerized liposomes are freeze-dried to obtain the polymerized liposome powder. There are two methods to redisperse lyophilized liposomes into water. The extrusion is an effective method to disperse them because the energy at extrusion is necessary only for redispersion, whereas the excess energy at sonication gives damage on liposome structure. There is no difference in stability between polymerized liposomes before and after redispersion with extrusion. DODPC polymers, obtained from free radical-initiated polymerization with AIBN, are linear and have polymerizable diene groups in 2-acyl chains. The liposome powder is therefore soluble in organic solvents. Reconstruction of polymerized liposomes is performed with lipid polymers having low or high molecular weight. The lipid polymers having high molecular weight provide stable large unilamellar liposomes by ethanol injection, but unstable small unilamellar liposomes are formed by sonication. The liposomes reconstructed from lipid polymers having low molecular weight are unstable regardless of their size. After reconstruction of liposomes selectively polymerized by AIBN, diene groups in 2-acyl chains are polymerized by water-soluble radical initiator or UV-irradiation to yield highly crosslinked structure. Their stability is improved remarkably by this postpolymerization.     

Polymerization of optically active 2-fluorophenyl-4-fluorophenyl-2-pyridylmethyl methacrylate with anionic and radical initiators: Stereospecificity and helix-sense selection

Almost optically pure (+)- and (−)-2-fluorophenyl-4-fluorophenyl-2-pyridylmethyl methacrylate (2F4F2PyMA) monomers were obtained by HPLC resolution of the racemic monomer and polymerized with the use of anionic and free-radical initiators. Helix-sense selectivity during the polymerization seemed to be governed mainly by the chirality of the monomer itself, and the polymers obtained by using the complex of N,N′-diphenylethylenediamine monolithium amide with (S)-(+)-1-(2-pyrrolidinylmethyl)pyrrolidine (PMP) in toluene at −78°C appeared to possess single-handed helical conformation (+)-poly[(−)-2F4F2PyMA], [α]₃₆₅ + 1510°; (−)-poly[(+)-2F4F2PyMA], [α]₃₆₅ − 1610°]. The single-handed helical (+)-poly[(−)-2F4F2PyMA] and (−)-poly[(+)-2F4F2PyMA] obtained with the PMP complex exhibited better chiral recognition ability toward trans-stilbene oxide compared with the single-handed helical poly(rac-2F4F2PyMA) prepared previously. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2645–2648, 1999     

高分子化Si桥联茂金属催化剂的合成及其催化乙烯聚合反应

合成了硅桥上含乙烯基团的硅桥联茂金属催化剂[(CH_2=CH)CH_3Si(C_5H_4) _2]ZrCl_2 (3)，并通过IR, ~1H NMR对化合物进行了表征，3在AIBN的引发下与苯 乙烯共聚形成高分子化的茂金属催化剂4。研究了3和4对乙烯聚合的能力，考察了 n(Al)/n(Zr)'温度对催化剂活性的影响。     

聚合脂质体固定对氨基苯甲脒及其对胰蛋白酶的亲和吸附作用

将对氨基苯甲脒是直接法和间接法固定到二十五－１０，１２－二炔－１－醇磷脂乙醇胺的聚合脂质体上，研究了聚合脂质体－对氨基苯甲脒对胰蛋白酶的亲和吸附作用。     

Interaction between (1,1'-Binaphthalene)-2,2'-diol and Lecithin Liposome

The interaction between (1,1′‐binaphthalene)‐2,2′‐diol (BINOL) and lecithin liposome was studied by UV‐Vis, fluorescence and ¹H NMR spectroscopies. BINOL can obviously associate with lecithin liposome and the preferential binding site of BINOL with lecithin liposome is located in the headgroup region. The hydrogen bond and electrostatic interaction should exist in BINOL/liposome system, which restricts intra‐annular rotation of naphthol moieties. Therefore, the fluorescence intensity of BINOL increases when a small quantity of liposome is added into the system. The partition coefficient K_D between the lecithin liposome and the aqueous phase is 310.9. With the increase of BINOL concentration, the micropolarity (I₁/I₃) and membrane fluidity of liposome decreased, while the viscosity of membrane increased.     

Radical polymerization of 3-methylene-5,5′-dimethyl-2-pyrrolidinone: A cyclic analog of N-substituted methacrylamide

3-Methylene-5,5′-dimethyl-2-pyrrolidinone (α-MDMP), a cyclic analog of N-substituted methacrylamide, was synthesized and polymerized with α,α′-azobis (isobutyronitrile) (AIBN) in solution. Poly(α-MDMP) is only soluble in dimethyl sulfoxide (DMSO) at room temperature. Thermogravimetry of poly(α-MDMP) showed 10% weight loss at 355°C in air and 400°C under nitrogen, respectively. The kinetics of α-MDMP homopolymerization with AIBN was investigated in DMSO. The rate of polymerization (R_p) can be expressed by R_p = k[AIBN]^0.49[α-MDMP]^1.0 and the overall activation energy has been calculated to be 73.2 kJ/mol. Monomer reactivity ratios in copolymerization of α-MDMP (M₂) with methyl methacrylate (M₁) are r₁ = 0.71 and r₂ = 0.71, from which Q and e values of α-MDMP are calculated as 0.75 and -0.43, respectively. © 1993 John Wiley & Sons, Inc.     

Syntheses of vinyl polymers containing a large π-electron cloud in the side chain

Several novel vinyl polymers containing five fused benzene rings in side chains were synthesized either by polymerization of the appropriate vinyl monomers or by chemical modification of the appropriate polymer. Thus, 3-(α-acryloyloxy)ethylperylene was prepared from perylene by Friedel-Crafts acylation with acetyl chloride and subsequent hydrogenation, followed by the reaction of the resulting alcohol with acryloyl chloride. 3-Acrylamido- or methacrylaminoperylene was prepared by the nitration of perylene, reduction of the resulting 3-nitroperylene, and the reaction with acryloyl or methacryloyl chloride. p-Vinylbenzal-3-acetylperylene was prepared by the condensation and dehydration reaction between p-vinylbenzaldehyde and 3-acetylperylene under alkaline medium, and, in the same manner, p-vinylbenzal-3-aminoperylene was prepared from p-vinyl benzaldehyde and 3-aminoperylene. All these monomers were polymerized with α,α′-azobisisobutyronitrile as catalyst in solution to afford the corresponding vinyl polymers. A vinyl polymer containing perylene-3-acetyl side chain was also prepared by the acetalization of poly(vinyl alcohol) with 3-formylperylene.     

Polymerization systems driven by aromatization energy: Anionic polymerization of 4-allylidene-2,6-dimethyl-2,5-cyclohexadien-1-one and spiro[2,5]octadienone derivatives

To investigate the polymerization systems driven by aromatization energy, 4-allylidene-2,6-dimethyl-2,5-cyclohexadien-1-one ( Ia ), 5,7-dimethyl-1-vinylspiro[2,5]octa-4,7-dien-6-one ( Ib ), 4,7-dimethyl-1-vinylspiro[2,5]octa-4,7-dien-6-one [ Ic ], 2-vinyl-2′-methylspiro[cyclopropane-1,4′-(1′-naphthalenone)] ( Id ), and 2-phenyl-2′-methylspiro[cyclopropane-1,4′-(1′-naphthalenone)] ( Ie ) were prepared and polymerized with sodium cyanide in N,N-dimethylformamide. Monomer Ia was highly polymerizable even at ?65°C. Monomers Ib–Ie also polymerized well, giving powdery polymers that were soluble in common solvents. All the polymerizations took place through the aromatization of the cyclohexadienone ring, suggesting that the aromatization energy is the driving force for the polymerization of these monomers.     

利用聚合脂质体的沉淀可逆性固定STI及其PL-STI对胰蛋白酶的亲和作用

通过双功能试剂戊二醛、二甘醇二酸酐和1,4-丁二醇双缩水甘油醚等将大豆胰蛋白酶抑制剂STI固定到由二十五-10,12-二块-1-醇磷脂乙醇胺形成的聚合脂质体上.同时探讨了其作为亲和沉淀吸附剂对对胰蛋白酶的亲和作用.在PL沉淀过程中,胰蛋白酶有20%～60%从PL-STI上解离下来.PL-STI可作为酶的亲和沉淀吸附剂.     

Stereoregularity of poly(methyl acrylate)

The stereoregularity of poly(methyl acrylate) and poly(methyl acrylate-αd) was determined from the NMR spectra. A method of quantitative determination of stereoregularity of poly(methyl acrylate) proposed in this paper is based on the fact that in the 100 Mc./sec. NMR spectrum the absorption peaks due to methylene protons in syndiotactic configurations overlap absorptions due to only one of two methylene protons in isotactic configurations. The stereostructure of poly(methy1 acrylates) polymerized with anionic catalysts such as Grignard reagents, n-butyllithium, and LiAlH₄ is generally richer in isotactic diads than in syndiotactic diads. For example, poly(methyl acrylate) polymerized with phenylmagnesium bromide as catalyst at ?20°C. consists of 99% isotactic and 1% syndiotactic diads. In radical polymerization, the isotacticity of poly(methyl acrylate) is independent of polymerization temperature. Poly(methyl acrylates) polymerized with a Ziegler-Natta catalyst consisting of Al(C₂H₅)₂Cl and VCl₄ have configurations similar to those polymerized by radical initiators. The stereoregularity of poly(methyl acrylate-α-d) resembled that of poly(methyl acrylate) polymerized under the same conditions.     

Polymerized Complex Route to the Synthesis of Pure SrTiO3 at Reduced Temperatures: Implication for Formation of Sr-Ti Heterometallic Citric Acid Complex

Powders of SrTiO3 were prepared by the Pechini-type polymerized complex technique, wherein a mixed solution of citric acid (CA), ethylene glycol (EG), Sr and Ti ions with a molar ratio of CA/EG/Sr/Ti = 10/40/1/1 was polymerized at 130°C to produce a yellowish transparent polyester-type resin without undergoing precipitation, which after decomposition on heating at 350°C was used as a powder precursor for SrTiO3. The formation of pure perovskite SrTiO3 practically free from carbonates occurred when the powder precursor was heat treated at temperatures higher than 500°C in static air. No X-ray diffraction and Raman spectroscopic evidence for phase separation of crystalline SrCO3 and TiO2 as distinct intermediates has been obtained during the thermal decomposition of the powder precursor, suggesting the molecular-scale mixing of cations in the Sr-Ti powder precursor. 13C-NMR spectroscopic measurements have indicated that unusual alkoxylation of CA occurred exclusively when both strontium and titanium ions in equal amounts coexist in CA/EG solutions, the phenomenon of which was discussed in connection with possible formation of a Sr-Ti heterometallic CA complex. The number of CA participating in formation of (Sr, Ti)-CAn was estimated to be n 3 from the variation of 13C-NMR spectra with relative concentrations of metal ions and CA. This heterometallic complex was thermally stable in CA/EG solutions upon heating at 130°C, implying that the molecular-level homogeneity achieved in the Sr/Ti precursor solution was preserved throughout the polymerization process.     

Controlled synthesis of carboxylic acid end‐capped poly(heptadecafluorodecyl acrylate) and copolymers with 2‐hydroxyethyl acrylate

1H,1H,2H,2H‐Heptadecafluorodecyl acrylate (AC8) was polymerized by reversible addition–fragmentation chain transfer and copolymerized with 2‐hydroxyethyl acrylate with the formation of random and block copolymers, respectively. The kinetics of the (co)polymerization was monitored with ¹H NMR spectroscopy and showed that the homopolymerization and random copolymerization of AC8 were under control. As a result of this control and the use of S‐1‐dodecyl‐S‐(α,α′‐dimethyl‐α″‐acetic acid)trithiocarbonate as a chain‐transfer agent, the copolymer chains were end‐capped by an α‐carboxylic acid group. Moreover, the controlled polymerization of AC8 was confirmed by the successful synthesis of poly(1H,1H,2H,2H‐heptadecafluorodecyl acrylate)‐b‐poly(2‐hydroxyethyl acrylate) diblock copolymers, which were typically amphiphilic compounds. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1499–1506, 2007     

Stereoregularity of poly(vinyl ether)

α-Methylvinyl isobutyl and methyl ethers were polymerized cationically and the structure of the polymers was studied by NMR. Poly(α-methylvinyl methyl ether) polymerized with iodine or ferric chloride as catalyst was found to be almost atactic, whereas poly(α-methylvinyl isobutyl ether) polymerized in toluene with BF₃OEt₂ or AlEt₂Cl as catalyst was found to be isotactic. In both cases, the addition of polar solvent resulted in the increase of syndiotactic structure as is the case with polymerization of alkyl vinyl ether. tert-Butyl vinyl ether was polymerized, and the polymer was converted into poly(vinyl acetate), the structure of which was studied by NMR. A nearly linear relationship between the optical density ratio D₇₂₂/D₇₃₆ in poly(tert-butyl vinyl ether) and the isotacticity of the converted poly(vinyl acetate) was observed.     

高分子化铁系烯烃聚合催化剂的合成及乙烯聚合

合成了含烯丙基不对称型的“茂后”催化剂[ArN=C(Me)][Ar'N=C(Me)]C~5H~3NFeCl~2[Ar=2,6-(i-Pr)~2C~6H~3,Ar'=4-烯丙基-2,6-(i-Pr)~2C~6H~3]，通过IR，^1HNMR,EI-MS,EA对化合物进行表征。利用这个催化剂上的烯烃基团在自由基引发下与苯乙烯共聚，制备出高分子化的“茂后”催化剂。研究了高分子化前后催化剂催化乙烯聚合行为，高分子化的催化剂在常压13℃下催化乙烯聚合时，活性最高达到2.5×10^6gPE/molFe.h，高于未高分子化之前催化剂的活性。证明了高分子化是“茂后”催化剂理想的固载化方式。     

Studies on metathetical and thermal polymerization of 5-norbornene 2,3-dicarboximide end-capped resins Pt-II

The article deals with synthesis, characterization, and polymerization of 5-norbornene-2,3-dicarboximide end-capped resins (bisnadimides) based on 4,4′-diaminodiphenylether, 1,4/1,3-bis(4′-aminophenoxy) benzene, 2,2′-bis[4-(4′-aminophenoxy)phenyl]propane, and bis[4-(4′-aminophenoxy)phenyl]sulphone. Both exo and endo bisnadimides were prepared by reacting the aromatic diamines with exo or endo nadic anhydride in glacial acetic acid at 120°C. The exo or endo bisnadimides could be distinguished on the basis of differences observed in IR or ¹H-NMR spectra. Both thermal (in solid state) and metathetical polymerization (using WCl₆/tetramethyltin catalyst and chlorobenzene solvent) of bisnadimides was carried out. Only exo bisnadimides could be polymerized using metathesis reaction whereas thermal polymerization of both endo and exo bisnadimide could be successfully carried out at 300°C in static air atmosphere. The polymers were highly crosslinked and insoluble in common organic solvents. The polymers obtained by metathesis polymerization were light brown in color whereas those obtained by thermal polymerization were dark brown in color. Thermal stability of the thermally polymerized exo or endo bisnadimides was comparable. These polymers were stable up to 400°C and decomposed in a single step above this temperature. The char yield at 800°C depended on the structure of the polymer and was in the 39–56% range. The polymers formed by metathesis polymerization showed a 1–3% weight loss in the temperature range 226–371°C and decomposed in a single step above 440°C. The char yields were higher in these polymers (53–71%) compared to those obtained by thermal polymerization. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 2323–2331, 1997     

Cyclodextrins in polymer synthesis: polymerization of methyl methacrylate under atom‐transfer conditions (ATRP) in aqueous solution

Host guest complexes of methyl methacrylate (MMA) and randomly methylated β‐cyclodextrin (m‐β‐CD, 1 a ) were polymerized in aqueous medium using atom‐transfer radical polymerization. Ethyl 2‐bromoisobutyrate (EBIB) was used as an initiator, copper(I) bromide as the catalyst, and bipyridine (bipy) or 4,4′‐di‐(5‐nonyl)‐2,2´‐bipyridine (dNbipy) as ligands. The unthreading of m‐β‐CD during the polymerization led to water‐insoluble poly(methyl methacrylate) (PMMA). It was found that using dNbipy resulted in higher monomer conversion than using bipy as the ligand under similar conditions. Furthermore, it is shown that the polymerization of MMA under these conditions has a living character. The polymers obtained have a much lower polydispersity than those obtained from conventional free‐radical polymerization. Also, the block copolymerization of PMMA bearing a bromoester end group with CD‐complexed styrene ( 2 a ) was carried out under ATRP conditions in aqueous medium.     

Syntheses of polymerizable viologens bearing a terminal vinyl group

Viologens that bore a terminal vinyl group were synthesized by four sequences of reactions: (1) N-vinylbenzyl-N′-n-propyl-4,4′-bipyridinium bromide chloride (V) was synthesized by the reaction of 4-(4′-pyrodyl)-N-n-propyl pyridinium bromide (III) with vinylbenzyl chloride; (2) N-β-acrylamidoethyl-N′-n-propyl-4,4′-bipyridinium dibromide (IX) was synthesized by the Menschutkin reaction of III with 2-aminoethyl bromide hydrobromide and subsequent reaction with acryloyl chloride; (3) N-β-methacryloyloxyethyl-N′-n-propyl-4,4′-bipyridinium dibromide and its analogs (XI) were synthesized by the reactions of III with the corresponding acyloxyalkyl bromides; and (4) N-vinyloxycarbonylmethyl-N′-n-propyl-4,4′-bipyridinium bromide chloride (XIII) was synthesized by the reaction of III with vinyl chloroacetate. With the exception of monomer XIII in which hydrolysis in large extent was observed during attempted polymerization, the synthesized monomers polymerized smoothly in aqueous solutions by a conventional radical procedure. Comparisons of the absorption peaks of the radical cations produced by reductions in aqueous solutions with those produced in films by ultraviolet (UV) irradiation indicate that the radical cations of polymers are associated intramolecularly in aqueous solutions.     

Pressure-Volume Behavior of PMMA-MMA Coexistence System as Polymerized at High Pressure

The pressure-volume (P-V) isotherms were measured for the poly(methy1 methacrylate) (PMMA)-methyl methacrylate (MMA) coexistence system polymerized by γ-ray irradiation at various pressures. The P-V isotherm of the coexistence system polymerized below 3000 kg/cm² was similar to that of the monomer. The specific volume of the coexistence system polymerized above 3000 kg/cm² hardly changes in the pressure range between 3000 kg/cm² and the polymerization pressure when measurements are made with successively decreasing or successively increasing pressures. The compressibility was of the order of 10^?6 (kg/cm²)^?1 in this pressure range. This indicated that the coexistence system polymerized above 3000 kg/cm² behaves like a solid in this pressure range. Above the polymerization pressure, the compressibility was of the order of 10^?5 (kg/cm²)^?1, indicating that the coexistence system behaves as liquid. We concluded that the solid-like behavior of the coexistence system polymerized above 3000 kg/cm² is caused by a strong interaction between as-polymerized polymer chains and monomer molecules due to propagation through monomer clusters having short-range order. The present results support that MMA is aligned in short-range order at suitable pressure and temperature as reported in the preceding paper.     

Incorporation of poly(2‐acrylamido‐2‐methyl‐N‐propanesulfonic acid) segments into block and brush copolymers by ATRP

2‐Acrylamido‐2‐methyl‐N‐propanesulfonic acid (AMPSA) was successfully polymerized via atom transfer radical polymerization (ATRP) using a copper chloride/2,2′‐bipyridine (bpy) catalyst complex after in situ neutralization of the acidic proton in AMPSA with tri(n‐butyl)amine (TBA). A 5 mol % excess of TBA was required to completely neutralize the acid and prevent protonation of the bpy ligand, as well as to avoid side reactions caused by large excess of TBA. The use of activators generated by electron transfer (AGET) ATRP with ascorbic acid as reducing agent resulted in both increased conversion of the AMPSA monomer during polymerization (up to 50% with a 0.8 [ascorbic acid]/[Cu(II)] ratio) and much shorter polymerization times (<30 min). Block copolymers and molecular brushes containing AMPSA side chains were prepared using this method, and the solution and surface behavior of these materials were investigated. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5386–5396, 2009