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1.
Two series of poly(ether imide)s (PEIs) containing fluorenyl cardo groups in the main chains were synthesized, which are derived from the polycondensation of 9,9′‐bis(4‐aminophenoxyphenyl)fluorene (BAOFL) or 9,9′‐bis(3‐trifluoromethyl,4‐aminophenoxyphenyl)fluorene (6F‐BAOFL) with four kinds of dianhydrides (3,3′,4,4′‐biphenyltetracarboxylic dianhydride, 4,4′‐oxydiphthalicanhydride, 3,3′,4,4′‐benzophenone tetracarboxylic dianhydride, and bisphenol‐A dianhydride), respectively. The PEI films and PEI powder were prepared by thermal and chemical imidization, respectively. The PEIs were characterized by FTIR, 1H‐NMR, differential scanning calorimetry, thermogravimetric analysis, and UV–vis were performed on inherent viscosity, solubility, and tensile tests. The effects of fluorenyl cardo groups and ether linkages on the solubility, tensile properties, thermal stability, and optical properties were investigated in detail. It was found that the PEIs had good solubility in common organic solvents and good optical transparency in visible light region. In addition, the PEI films exhibited excellent tensile and thermal properties. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

2.
以甲基丙烯酰氧乙基二甲基胺(DM)和1,3-丙基磺内酯为原料,在55℃下反应20 h,合成了3-(2-甲基丙烯酰氧乙基二甲胺基)丙磺酸盐(DMAPS);并在盐溶液中与丙烯酰胺(AM)单体进行自由基共聚合反应,获得了净电荷为零的磺基甜菜碱型两性离子共聚物P(AM-DMAPS);采用红外光谱对共聚物进行表征;考察了总单体的质量分数、单体摩尔分数、引发剂用量、反应时间、反应温度、c(NaCl)以及氧化剂与还原剂的物质的量比等因素对聚合反应的影响;获得最佳反应条件:总单体的质量分数25%,x(DMAPS)=5%,w(引发剂)=0.03%,反应时间10 h,反应温度25℃,c(盐)=0.5 mol/L,n(氧化剂)∶n(还原剂)=1.4∶1。在此条件下获得的共聚物特性粘数为18.5 mL/g。  相似文献   

3.
A new amphiphilic copolymer (copoly‐(MR‐BMA‐HEA‐MAA), PRBHM) containing multihydroxyl segments was designed and synthesized for application in drug carrier. PRBHM can be dissolved in water to form aggregates directly with a critical aggregate concentration (CAC) of 0.0138 mg mL?1. The chains of PRBHM can be collapsed into hydrophobic globules when pH decreases from neutral to slightly acid condition (pH = 5.0–7.0) in water. Since the hydrophilic hydroxyl group is independent on pH, PRBHM can keep stable both in neutral and slightly acid aqueous solutions. The hydrophobic small molecules such as 5‐(4‐(4‐vinylbenzyloxy) phenyl)‐4,5‐dihydro‐1,3‐diphenyl‐1H‐pyrazole (PY) can be loaded into PRBHM aggregates via ultrasonic treatment in water, and can be internalized into BEL‐7402 cancer cells. The cytotoxicity determination also indicates the good biocompatibility of PRBHM in potential application as a drug carrier. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

4.
向远清  刘朋生 《弹性体》2002,12(4):24-27
以AIBN为引发剂,采用溶液聚合法合成了苯乙烯-马来酸酐交替共聚物(SMA),并使其在溶液中与液化MDI进行接枝聚合,用IR,DSC,TG等对接枝聚合物给予了表征,结果表明:SMA与液化MDI之间进行了接枝聚合,接枝聚合物有一玻璃化转变温度Tg,它的热稳定性能较MA与液化MDI的直接反应产物有所提高。  相似文献   

5.
Summary Alternating copolyimides and homopolyimides of pyromellitic dianhydride and benzophenonetetracarboxylic dianhydride containing aliphatic spacers have been synthesized by the solution polycondensation of N,N-bis(isocyanatoalkyl)-1,2,4,5-benzenetetracarboxylic-1,2:4,5-diimides and N, N-bis(isocyanatoalkyl)-3,3: 4,4-diimides with pyromellitic dianhydride (PMDA) and benzophenonetetracarboxylic dianhydride (BTDA) in dimethylacetamide. These polyimides are semicrystalline, thermally stable and soluble in polar aprotic solvents with inherent viscosities in the range 0.29 – 0.62 dL/g in m-cresol.NCL Communication No. 4896  相似文献   

6.
A novel soluble alternating conjugated copolymer, comprised of 3-dodecyloxythiophene and pyridine moieties, was synthesized via the Heck Couple approach. Regioregular poly(3-dodecyloxythiophenel) synthesized by McCullough was also studied for comparison. The obtained polymers were characterized by 1H NMR, HR-MS, gel permeation chromatography, UV–Vis spectroscopy, photoluminescence and Cyclic voltammetry. The photoluminescence of the copolymer exhibited extraordinary bright blue. The electrochemical study shows that the new alternating copolymer does not merely have the properties of the two units that constitute it but has mutual hole and electron charge carrier properties which might be promising material for applications in high efficiency, single or low number layers functional devices.  相似文献   

7.
A series of novel fluorinated aromatic polyesters containing trifluoromethylphenoxy pendant groups was synthesized by interfacial polycondensation of 2‐(4‐trifluoromethylphenoxy)terephthalyl chloride with various bisphenols in dichloromethane. The polyesters obtained in good yields had weight‐average molecular weights of 70,600–29,800 g/mol, polydispersities of 1.81–2.08, and were all amorphous. All polyesters were easily soluble in organic solvents such as N,N‐dimethylformamide, tetrahydrofuran, o‐chlorophenol, pyridine, and dichloromethane. These fluorinated polyesters showed glass transition temperature of 133–210°C, and good thermal stability with almost no weight loss up to 378°C, the 10% weight loss temperature of 472–523°C as well as char yield of 32–63% at 600°C in nitrogen. These polyester films cast from chloroform solutions exhibited tensile strengths ranging from 102 to 126 MPa, elongation at break from 6.3% to 11.7%, and tensile moduli from 2.1 to 3.3 GPa. The resulting polyester films also displayed low dielectric constants between 2.18 and 2.49 (1 MHz), high transparency with an ultraviolet‐visible absorption cut‐off wavelengths in the 332–355 nm range, and excellent electric strengths (50.4–65.6 kV/mm) and volume resistivity (2.51–6.03 × 1016 Ω cm). © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

8.
High yield and pure zinc glutarate catalysts used for copolymerization of carbon dioxide and propylene oxide have been synthesized in different solvents by ultrasonic methodology. For the purposes of comparison, low‐yield zinc glutarates were also synthesized via mechanical stirring method with other synthetic conditions remaining unchanged. Fourier Transform Infrared Spectroscopy and wide‐angle X‐ray diffraction techniques confirmed the presence of high‐quality zinc glutarate catalysts. Accordingly, poly(propylene carbonate) (PPC) can be synthesized from carbon dioxide and propylene oxide using the zinc glutarate catalysts. It was confirmed that the as‐prepared PPC had an alternating copolymer structure together with high molecular weight. The thermal and mechanical properties of the obtained PPC copolymer were determined by means of differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and tensile test. DSC and TGA results showed that the PPC copolymer exhibited high glass transition temperature (39.39°C) and decomposition temperature (278°C) when compared to their corresponding values reported in the literature. Tensile test showed that the PPC film exhibited superior mechanical strength. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2327–2334, 2002  相似文献   

9.
Novel fluorenyl cardo chain‐extended bismaleimides (FCCEBMIs) were synthesized by reacting maleic anhydride with fluorenyl cardo diamine and different dianhydrides. FCCEBMIs were characterized by FT‐IR spectra (FT‐IR), 1H NMR, and elemental analysis. All FCCEBMI monomers were readily soluble in a variety of organic solvents, such as N‐methyl‐2‐pyrrolidinone, N,N‐dimethyl acetamide, chloroform (CHCl3), methylene chloride (CH2Cl2), dimethyl sulfoxide, and tetrahydrofuran when compared with 9,9‐bis(4‐maleimidophenyl) fluorene. Curing process was investigated by differential scanning calorimetry. Thermal properties of the cured FCCEBMIs were characterized by thermogravimetry analysis, the cured products are stable up to 430°C. The results show that the FCCEBMIs with imide structure improve significantly the solubility of bismaleimide (BMI) in organic solvents without sacrificing thermal properties of cured BMIs. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

10.
用α-溴代丙酸乙酯(EPN—B)/氯化亚铜(CuCl)/联二吡啶(bpy)作为催化引发体系,环己酮为溶剂,进行甲基丙烯酸2,2,2-三氟乙酯(TFEMA)的原子转移自由基聚合(ATRP),得到单分散PTFEMA—X预聚体。并以此预聚体为大分子引发剂引发甲基丙烯酸-β-羟乙酯聚合,得到分子质量可控、分子质量分布窄的聚甲基丙烯酸2,2,2-三氟乙酯-b-聚甲基丙烯酸-β-羟乙酯嵌段共聚物,用FTIR、^1H—NMR、GPC等对产物的结构与性能进行了表征。同时利用动态激光光散射(DLS)对嵌段共聚物的自组装行为进行了研究。  相似文献   

11.
The incorporation of alkoxysilanes into latex systems is of major interest in the field of colloidal science. Two novel vinyl-containing alkoxysilanes, 3-(trimethoxysilyl) propylthiomethacrylate (TMSPTM) and methacryloxyethyl triethoxysilylpropylcarbamate (METESPC) were prepared by the condensation reaction of methacryloyl chloride (MC) with (3-mercaptopropyl)-trimethoxysilane (MPTMS) and addition reaction of 2-hydroxyethyl methacrylate (HEMA) with (3-isocyanatopropyl) triethoxysilane (ICPTES), respectively. Then these monomers were copolymerized with vinyl acetate and 2-ethylhexylacrylate (VAc/2-EHA) by seeded emulsion polymerization, and copolymer latexes were obtained. One kind of vinyl-containing alkoxysilane, the triethoxyvinylsilane (TEVS) has been used as coupling reagent for comparison of the effects of alkoxysilane types on the latexes. The structural elucidation of monomers was carried out by FT-IR, 1H NMR, and 13C NMR spectroscopic techniques. The VAc/2-EHA copolymer latexes with TMSPTM or MPTMS were also characterized by FT-IR. The thermal stability of copolymers was respectively studied by thermogravimetric analysis (TGA) and dynamic mechanical thermal analysis (DMTA). The morphologies of the latexes were characterized with scanning electron microscopy (SEM).  相似文献   

12.
We report a novel method to fabricate fluorescent polymer (F-CPA) based on the esterification between acrylate copolymer (CPA) and fluorescein using N, N-dicyclohexylcarbodiimide (DCC)/4-dimethylaminopyridine (DMAP) as catalyst. The resulting copolymer was characterized by Fourier transform-infrared spectroscopy (FT-IR), gel permeation chromatography (GPC), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), ultravioletvisible spectroscopy (UV-Vis) and fluorescence spectroscopy. In addition, the influences of concentration, solvents, pH and metal cations (Cu2+, Fe3+ and Zn2+) on the fluorescent behaviors of F-CPA are discussed in detail. All those observations suggest that the synthesized F-CPA is an excellent luminescent macromolecular material with simple synthesis method and excellent solubility. Moreover, its sensitive fluorescence response behaviors to solvents, pH and metal cations make it to become a polymer-based probe.  相似文献   

13.
Polyamides containing arylene sulfide as well as arylene sulfide-sulfone linkages were prepared from bis(4-phenylthio)dibenzoyl chloride (BPCl), 4,4′-[sulfonylbis(4-phenylthio)]dibenzoyl chloride (SPCl) and aromatic diamines both by solution and interfacial polymerization techniques. In the solution polymerization the effect of two different acid acceptors, lithium chloride and triethylamine, on inherent viscosity of the polyamides was studied. The effect of aromatic sulfone ether diamines and conventional aromatic diamines on viscosity and thermal properties of polyamides was also investigated. The polyamides prepared were characterized by IR, 1H NMR, elemental analysis, solution viscosity, thermogravi-metry, differential scanning calorimetry and X-ray diffraction. Thermal and physical properties of polyamides prepared from BPCl and SPCl were compared.  相似文献   

14.
Summary Polyacrylates containing para-nitro azobenzene have been synthesized by free radical polymerization. The influence of the length of the spacer of the homopolyacrylates (HPn, n=3,4,6), content of methyl acrylate in the copolyacrylates (CP6) with para-nitro azobenzene groups on the thermal properties, such as liquid crystallinity, Tg and Tm, was studied by DSC, WAXD and polarized optical microscopy. Among the polymers studied, only the homopolyacrylate (HP6) with six carbon atoms in the spacer exhibited a nematic phase. The second-harmonic generation (SHG) signal of the poled HP6 film was detected qualitatively by Maker-fringer method.  相似文献   

15.
Thermosensitive 4VP‐NIPAAm‐4G copolymer beads containing pyridyl groups were first prepared by suspension copolymerization of 4‐vinylpyridine (4VP), N‐isopropylacrylamide(NIPAAm), and tetraethylene glycol dimethacrylate (4G; crosslinking reagent) in a saturated Na2SO4 aqueous solution in the presence of surfactant and MgCO3 as dispersants. Then the copolymer beads containing pyridinium groups were obtained by the quaternization of the copolymer beads with various alkyl iodides (CH3I, C4H9I, C8H17I) in N,N‐dimethylformamide. The 4VP‐NIPAAm‐4G (15 : 97 : 3) copolymer bead and the 4VP‐NIPAAm‐4G copolymer beads quaternized with butyl iodide exhibited high thermosensitivity in water, although the 4VP‐NIPAAm‐4G copolymer beads quaternized with methyl iodide or octyl iodide hardly exhibited thermosensitivity. All the quaternized copolymer beads exhibited antibacterial activity against Escherichia coli (E. coli), although the 4VP‐NIPAAm‐4G copolymer bead did not. In particular, the copolymer bead quaternized with butyl iodide exhibited the highest antibacterial activity against E. coli at 30°C. It was also found that the antibacterial activity of the quaternized 4VP‐NIPAAm‐4G copolymer beads was greatly affected by not only chain length of alkyl groups in alkyl iodides, with which the 4VP‐NIPAAm‐4G copolymer beads were quaternized, but also by temperature of the solutions. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

16.
17.
The double-hydrophilic multiblock copolymers poly(ethylene glycol)-b-poly((2-acrylamido-2-methyl propanesulfonic sodium) (PEG-b-PAMPSNa) with different PEG and PAMPSNa ratio have been synthesized. The copolymers were characterized by FTIR, 1H-NMR, elemental analysis, thermogravimetric analysis (TGA) and Gel permeation chromatography coupled with multi-angle light scattering laser light scattering (GPC-MALLS). According to the results, it was seen that the compositions had obvious influences to the characteristics of the copolymers. With more PEG content in the copolymers, the molecular weights and thermal stability increased, and the copolymers chain structures were more flexible. The solution properties of the copolymers were studied by dynamic light scattering (DLS), which also have great relationship with the copolymers compositions. And PEG-b-PAMPSNa was used as a crystal growth modifier to control the crystallization of BaSO4 in its aqueous solution. The morphologies and sizes of BaSO4 crystals can be well controlled by the copolymer. With the increasing concentration, the copolymer assembled in water and interacted with inorganic particles on the crystal faces, which is concerned with the controlling of crystal growth in solution.  相似文献   

18.
合成、表征了一种含有羧基的新型蒽醌衍生物——1-[N-(6-羧基戊基酰基)]氨基蒽醌。  相似文献   

19.
Akito Fukui 《Polymer》2009,50(17):4159-5967
Diarylacetylenes having fluorenyl groups and other substituents (trimethylsilyl, t-butyl, bromine, fluorine) (1a-1) were polymerized with TaCl5-n-Bu4Sn. Monomers 1a-l produced high molecular weight polymers 2a-l (Mw 5.1 × 105-1.3 × 106) in 12-59% yields. All of the polymers were soluble in common organic solvents, and gave tough free-standing membranes by the solution casting method. The onset temperatures of weight loss of polymers 2a-l in air were over 400 °C, indicating considerably high thermal stability. All the polymer membranes showed high gas permeability; e.g., the oxygen permeability coefficient (PO2) of 2a was as large as 4800 barrers. Membrane 2d possessing two fluorine atoms at meta and para positions of the phenyl ring showed the highest oxygen permeability (PO2 = 6600 barrers) among the present polymers.  相似文献   

20.
The possibility of reinforcing polyethylene (PE) by blending it with a liquid crystalline polymer (LCP) rests on the successful improvement of phase compatibility and interfacial adhesion of these two structurally unlike polymers. The approach that is being considered in our laboratories consists of the synthesis of PE–LCP block or graft copolymers and of their use as compatibilizing agents for PE/LCP blends. In this work, the melt polycon-densation of sebacic acid (S), 4,4′-dihydroxybiphenyl (B), and 4-hydroxybenzoic acid (H) has been carried out at temperatures up to 280°C in the presence of an oxidized low molar mass PE sample containing free carboxylic groups (PEox), with the main scope of demonstrating that a PE-g-LCP copolymer may be synthesized by this route. The polycon-densation product has been fractionated by successive extractions with boiling toluene and xylene. The soluble fractions and the residues have been characterized by IR and NMR spectroscopy, differential scanning calorimetry (DSC), thermogravimetric analysis (TG, DTG), and scanning electron microscopy (SEM). The extractions and the analyses have been repeated on a PEox/LCP blend prepared by melt mixing PEox and preformed LCP (SBH 112, by Eniricerche). The results show that, whereas for the blend a fairly clean separation of PEox and SBH can be obtained by solvent extraction, this is not so for the polycondensation product. All analytical procedures concordantly show that a PEox-g-SBH copolymer has, in fact, been obtained. In effect, both PEox and SBH chain segments are present, with different relative ratios, in all fractions of the polycondensate. Moreover, a fairly quantitative esterification of the PEox carboxyl groups has been shown by IR analysis to take place in the adopted conditions. Preliminary morphological investigations carried out by SEM have shown that the addition of the synthesized graft copolymer into HDPE/SBH blends leads to an improvement of the interfacial adhesion. © 1996 John Wiley & Sons, Inc.  相似文献   

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