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1.
The free‐radical copolymerization of N‐phenylmaleimide (N‐PhMI) with acrylic acid was studied in the range of 25–75 mol % in the feed. The interactions of these copolymers with Cu(II) and Co(II) ions were investigated as a function of the pH and copolymer composition by the use of the ultrafiltration technique. The maximum retention capacity of the copolymers for Co(II) and Cu(II) ions varied from 200 to 250 mg/g and from 210 to 300 mg/g, respectively. The copolymers and polymer–metal complexes of divalent transition‐metal ions were characterized by elemental analysis, Fourier transform infrared, 1H NMR spectroscopy, and cyclic voltammetry. The thermal behavior was investigated with differential scanning calorimetry (DSC) and thermogravimetry (TG). The TG and DSC measurements showed an increase in the glass‐transition temperature (Tg) and the thermal stability with an increase in the N‐PhMI concentration in the copolymers. Tg of poly(N‐PhMI‐co‐AA) with copolymer composition 46.5:53.5 mol % was found at 251 °C, and it decreased when the complexes of Co(II) and Cu(II) at pHs 3–7 were formed. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4933–4941, 2005  相似文献   

2.
In this work, we investigate the influence of the amide solvent chemical structure on the properties of poly(3‐hexylthiophene) (P3HT) prepared via direct arylation polymerization (DArP). Our findings indicate that for successful polymerization the amide must possess an acyclic aliphatic structure since cyclization of an amide results in a complete shutdown of DArP reactivity as evidenced by failed polymerization in N‐methylpyrrolidone, whereas the presence of an aromatic motif renders the amide solvent susceptible to C? H activation and leads to incorporation of the solvent structure into the P3HT backbone, as demonstrated on the example of N,N‐diethylbenzamide. Additionally, we observed that the steric bulk of alkyl substituents on both the nitrogen atom and the carbonyl group within the amide structure has to be delicately balanced for optimal DArP reactivity. In the optimal cases, P3HT is obtained in high yield, with high molecular weight and contains a minimal amount of structural defects. The obtained polymer samples were comprehensively studied in terms of their chemical structure, optical, thermal and solid‐state properties in thin films using GPC analysis, 1H NMR, MALDI, UV–vis, GIXRD spectroscopy, and DSC. We additionally note a drastic difference of the amide solvent effect between DArP and Stille polymerization. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2494–2500  相似文献   

3.
A new N‐phenylated amide (N‐phenylamide) unit containing aromatic diamine, N,N′‐bis(3‐aminobenzoyl)‐N,N′‐diphenyl‐1,4‐phenylenediamine, was prepared by the condensation of N,N′‐diphenyl‐1,4‐phenylenediamine with 3‐nitrobenzoyl chloride, followed by catalytic reduction. Two series of organosoluble aromatic poly(N‐phenylamide‐imide)s and poly(N‐phenylamide‐amide)s with inherent viscosities of 0.58–0.82 and 0.56–1.21 dL/g were prepared by a conventional two‐stage method and the direct phosphorylation polycondensation, respectively, from the diamine with various aromatic dianhydrides and aromatic dicarboxylic acids. All polyimides and polyamides are amorphous and readily soluble in many organic solvents such as N,N‐dimethylacetamide and N‐methyl‐2‐pyrrolidone. These polymers could be solution cast into transparent, tough, and flexible films with high tensile strengths. These polyimides and polyamides had glass‐transition temperatures in the ranges of 230–258 and 196–229 °C, respectively. Decomposition temperatures of the polyimides for 10% weight loss all occurred above 500 °C in both nitrogen and air atmospheres. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2564–2574, 2002  相似文献   

4.
A diimide dicarboxylic acid, 1,4‐bis(4‐trimellitimidophenoxy)naphthalene (1,4‐BTMPN), was prepared by condensation of 1,4‐bis(4‐aminophenoxy)naphthalene and trimellitic anhydride at a 1 : 2 molar ratio. A series of novel poly(amide‐imide)s (IIa–k) with inherent viscosities of 0.72 to 1.59 dL/g were prepared by triphenyl phosphite‐activated polycondensation from the diimide‐diacid 1,4‐BTMPN with various aromatic diamines (Ia–k) in a medium consisting of N‐methyl‐2‐pyrrolidinone (NMP), pyridine, and calcium chloride. The poly(amide‐imide)s showed good solubility in NMP, N,N‐dimethylacetamide, and N,N‐dimethylformamide. The thermal properties of the obtained poly(amide‐imide)s were examined with differential scanning calorimetry and thermogravimetry analysis. The synthesized poly(amide‐imide)s possessed glass‐transition temperatures in the range of 215 to 263°C. The poly(amide‐imide)s exhibited excellent thermal stabilities and had 10% weight losses at temperatures in the range of 538 to 569°C under a nitrogen atmosphere. A comparative study of some corresponding poly(amide‐imide)s also is presented. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1–8, 2000  相似文献   

5.
A dicarboxylic acid {1,1‐bis[4‐(4‐trimellitimidophenoxy)phenyl]‐1‐phenylethane ( II )} bearing two performed imide rings was prepared from the condensation of 1,1‐bis[4‐(4‐aminophenoxy)phenyl]‐1‐phenylethane and trimellitic anhydride in a 1/2 molar ratio. A novel family of poly(amide‐imide)s with inherent viscosities of 0.83–1.51 dL/g was prepared by triphenyl phosphite‐activated polycondensation from the diimide‐diacid II with various aromatic diamines in a medium consisting of N‐methyl‐2‐pyrrolidinone (NMP), pyridine, and calcium chloride. Because the 1,1,1‐triphenylethane group of II was unsymmetrical, most of the resulting polymers showed an amorphous nature and were readily soluble in polar solvents such as NMP and N,N‐dimethylacetamide. All the soluble poly(amide‐imide)s afforded tough, transparent, and flexible films, which had tensile strengths ranging from 88 to 102 MPa, elongations at break from 6 to 11%, and initial moduli from 2.23 to 2.71 GPa. The synthesized poly(amide‐imide)s possessed glass‐transition temperatures from 250 to 287 °C. The poly(amide‐imide)s exhibited excellent thermal stabilities and had 10% weight losses from 501 to 534 °C under a nitrogen atmosphere. A comparative study of some corresponding poly(amide‐imide)s is also presented. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 775–787, 2001  相似文献   

6.
A series of new soluble poly(amide‐imide)s were prepared from the diimide‐dicarboxylic acid 2,2‐bis[4‐(4‐trimellitimidophenoxy)phenyl]hexafluoropropane with various diamines by direct polycondensation in N‐methyl‐2‐pyrrolidinone containing CaCl2 with triphenyl phosphite and pyridine as condensing agents. All the polymers were obtained in quantitative yields with inherent viscosities of 0.52–0.86 dL · g?1. The poly(amide‐imide)s showed an amorphous nature and were readily soluble in various solvents, such as N‐methyl‐2‐pyrrolidinone, N,N‐dimethylacetamide (DMAc), N,N‐dimethylformamide, pyridine, and cyclohexanone. Tough and flexible films were obtained through casting from DMAc solutions. These polymer films had tensile strengths of 71–107 MPa and a tensile modulus range of 1.6–2.7 GPa. The glass‐transition temperatures of the polymers were determined by a differential scanning calorimetry method, and they ranged from 242 to 279 °C. These polymers were fairly stable up to a temperature around or above 400 °C, and they lost 10% of their weight from 480 to 536 °C and 486 to 537 °C in nitrogen and air, respectively. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3498–3504, 2001  相似文献   

7.
We report the preparation and characterization of a series of novel electrochromic, aromatic poly(amine amide)s with pendent triphenylamine units. The synthesis proceeded via direct phosphorylation polycondensation between a novel diamine, N,N‐bis(4‐aminophenyl)‐N′,N′‐diphenyl‐1,4‐phenylenediamine, and various aromatic dicarboxylic acids. All the poly(amine amide)s were amorphous and readily soluble in many common organic solvents and could be solution‐cast into transparent, tough, and flexible films with good mechanical properties. They exhibited good thermal stability and 10% weight‐loss temperatures above 540 °C. Their glass‐transition temperatures were 263–290 °C. These polymers in N‐methyl‐2‐pyrrolidinone solutions exhibited strong ultraviolet–visible absorption peaks at 307–358 nm and photoluminescence peaks around 532–590 nm in the green region. The hole‐transporting and electrochromic properties were studied with electrochemical and spectroelectrochemical methods. Cyclic voltammograms of poly(amine amide) films prepared by the casting of polymer solutions onto an indium tin oxide coated glass substrate exhibited two reversible oxidation redox couples at 0.65 and 1.03 V versus Ag/AgCl in an acetonitrile solution. All the poly(amine amide)s showed excellent stability with respect to their electrochromic characteristics; the color of the films changed from pale yellow to green and then blue at 0.85 and 1.25 V, respectively. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2085–2098, 2005  相似文献   

8.
An imidazole‐terminated hyperbranched polymer with octafunctional POSS branching units denoted as POSS‐HYPAM‐Im was prepared by the polymerization of excess amounts of tris(2‐aminoethyl)amine with the first‐generation methyl ester‐terminated POSS‐core poly(amidoamine)‐typed dendrimer, reacting with methyl acrylate, and ester‐amide exchange reaction with 3‐aminopropylimidazole. The imidazole‐terminated hyperbranched poly(amidoamine) denoted as HYPAM‐Im was also synthesized with 1‐(3‐aminopropyl)imidazole from a methyl ester‐terminated hyperbranched poly(amidoamine) by the ester‐amide exchange reaction. The transmittance of the POSS‐HYPAM‐Im solution drastically decreased when the solution pH was greater than 8.2. On the other hand, the transmittance of the HYPAM‐Im solution gradually decreased when the solution pH at 8.5 and was greater than 9. Spectrophotometric titrations of the hyperbranched polymer aqueous solutions with Cu2+ ions indicated the variation of the coordination modes of POSS‐HYPAM‐Im from the Cu2+–N4 complex to the Cu2+–N2O2 complex and the existence of the only one complexation mode of Cu2+–N4 between Cu2+ ion and HYPAM‐Im with increasing the concentrations. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2695–2701  相似文献   

9.
The controlled polymerization of methyl methacrylate (MMA) in bulk was initiated with p‐chlorobenzenediazonium tetrafluoroborate ( 1 ) and Cu(II) or Cu(I)/Cu(II)/N,N,N′,N″,N″‐pentamethyldietylene triamine (PMDETA) complex system at various temperatures (20, 60, and 90 °C). The proposed polymerization mechanism is based on the Meerwein‐type arylation reaction followed by a reverse atom transfer radical polymerization. In this mechanism, aryl radicals formed by the reaction with 1 and Cu(I) and/or PMDETA initiated the polymerization of MMA. The polymerization is controlled up to a molecular weight of 46,000 at 90 °C. Chain extension was carried out to confirm the controlled manner of the polymerization system. In all polymerization systems, the polydispersity index and initiator efficiency ranged from 1.10–1.57 to 0.10–0.21, respectively. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2019–2025, 2003  相似文献   

10.
A new type of tetraimide‐dicarboxylic acid ( I ) was synthesized starting from the ring‐opening addition of m‐aminobenzoic acid, 4,4′‐oxydiphthalic anhydride, and 2,2‐bis[4‐(4‐aminophenoxy)phenyl]propane at a 2:2:1 molar ratio in N‐methyl‐2‐pyrrolidone (NMP), followed by cyclodehydration to the diacid I . A series of soluble and light‐colored poly(amide‐imide‐imide)s ( III a–j) was prepared by triphenyl phosphite‐activated polycondensation from I with various aromatic diamines ( II a–j). All films cast from N,N‐dimethylacetamide (DMAc) had cutoff wavelengths shorter than 390 nm (374–390 nm) and b* values between 25.26 and 43.61; these polymers were much lighter in color than the alternating trimellitimide series. All of the polymers were readily soluble in a variety of organic solvents such as NMP, DMAc, N,N‐dimethylformamide, dimethyl sulfoxide, and even in less polar m‐cresol and pyridine. Polymers III a–j afforded tough, transparent, and flexible films that had tensile strengths ranging from 96 to 118 MPa, elongations at break from 9 to 11%, and initial moduli from 2.0 to 2.5 GPa. The glass‐transition temperatures of the polymers were recorded at 240–268 °C. They had 10% weight loss at a temperature above 540 °C and left more than 55% residue even at 800 °C in nitrogen. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 707–718, 2002; DOI 10.1002/pola.10153  相似文献   

11.
Poly(N‐acryloyl‐N′‐methylpiperazine) (PAMP) forms complexes with four strong acidic polymers, namely, poly(styrenesulfonic acid), poly(vinylphosphonic acid), poly(acrylic acid) and poly(methacrylic acid) in ethanol/water (1:1) solution. The nature of interpolymer interactions in various complexes was studied by Fourier transform infrared (FTIR) spectroscopy and X‐ray photoelectron spectroscopy (XPS). Both the carbonyl oxygen and the amide nitrogen of PAMP are involved in hydrogen‐bonding interactions. Some of the amine nitrogens of PAMP are protonated and therefore PAMP also interacts with the acidic polymers through ionic interactions. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 501–508, 2000  相似文献   

12.
When poly(N‐vinyl pyrrolidone‐co‐vinyl acetate) (PVP‐co‐PVAc) containing amide and ester groups were complexed with silver salts to form silver polymer electrolyte membranes, their separation performance of propylene/propane mixtures showed the high selectivity of propylene over propane of 55 and the high mixed gas permeance of 12 GPU (1 GPU = 1.0 × 10?6 cm3(STP) cm?2 s?1 cmHg?1). The separation performance strongly depends on the composition of the copolymer: the higher concentration of PVP in the copolymer, the better separation performance was achieved. These results suggest that the amide group is more effective in facilitated propylene transport than the ester group, primarily due to the stronger interaction of the silver ions with the amide than the ester oxygens, as demonstrated by FT‐IR and FT‐Raman spectroscopies. In‐situ FT‐IR spectra upon propylene sorption also demonstrate that the interaction strength of the silver ions with the ligands is arranged: amide > C?C > ester. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2263–2269, 2007  相似文献   

13.
This study synthesized thermo‐sensitive amphiphilic block‐graft PNiPAAm‐b‐(PαN3CL‐g‐alkyne) copolymers through ring‐opening polymerization of α‐chloro‐ε‐caprolactone (αClCL) with hydroxyl‐terminated macroinitiator poly(N‐isopropylacrylamide) (PNiPAAm), substituting pendent chlorides with sodium azide. This was then used to graft various kinds of terminal alkynes moieties by means of the copper‐catalyzed Huisgen's 1,3‐dipolar cycloaddition (“click” reaction). 1H NMR, FTIR, and gel permeation chromatography (GPC) was used to characterize these copolymers. The solubility of the block‐graft copolymers in aqueous media was investigated using turbidity measurement, revealing a lower critical solution temperature (LCST) in the polymers. These solutions showed reversible changes in optical properties: transparent below the LCST, and opaque above the LCST. The LCST values were dependant on the composition of the polymer. With critical micelle concentrations (CMCs) in the range of 2.04–9.77 mg L?1, the block copolymers formed micelles in the aqueous phase, owing to their amphiphilic characteristics. An increase in the length of hydrophobic segments or a decrease in the length of hydrophilic segments amphiphilic block‐graft copolymers produced lower CMC values. The research verified the core‐shell structure of micelles by 1H NMR analyses in D2O. Transmission electron microscopy was used to analyze the morphology of the micelles, revealing a spherical structure. The average size of the micelles was in the range of 75–145 nm (blank), and 105–190 nm (with drug). High drug entrapment efficiency and drug loading content were observed in the drug micelles. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   

14.
With a hydrogen‐bonding template, a novel soluble aryl amide‐bridged ladderlike polysiloxane, containing naphthyl as the side‐chain group, has been successfully synthesized via a stepwise coupling polymerization. It is proposed that the monomer, N,N′‐di(3‐naphthyldiethoxylsilyl‐propyl)‐[4,4′‐oxybis(benzyl amide)], prepared by Grignard and hydrosilylation reactions, undergoes self‐assembly first via amido hydrogen bonding and then via hydrolysis, followed by condensation under controlled reaction conditions to yield a high molecular weight, soluble, dark yellow polymer. The analytical results (Fourier transform infrared, 1H NMR, 29Si NMR, X‐ray diffraction, differential scanning calorimetry, and vapor pressure osmometry) show that the polymer possesses an ordered ladderlike architecture. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 636–644, 2003  相似文献   

15.
A method is presented for generation of all surface‐bound radicals on solid polymer surfaces. Thus, secondary amide group of newly synthesized crosslinking comonomer, methacryloyloxyethyl methacrylamide was determined as versatile precursor for generation fixed diradicals on solid microspheres, obtained by copolymerization with methyl methacrylate (MMA) in aqueous suspension. Nitrosoation of the secondary amide groups on the microbeads and followed thermolysis above 90 °C was demonstrated to give surface‐bound radicals, capable of initiating polymerization of vinyl monomers, such as; styrene, MMA, N‐vinyl formamide, and N‐vinyl, 2‐pyrrolidone, as evidenced by H NMR, Fourier transform infrared, thermogravimetric analysis, and differential scanning calorimeter techniques. Appreciable grafting yields (55.1%–286.1%) and low free‐homopolymer formation (7.2%–19.7%) were noted within 6 h of the grafting at 100 °C in each case. This strategy involving the use of amide functional crosslinker seemed to be generally applicable to generate surface‐bound radicals for surface‐initiated polymerization from various solid substrates. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

16.
A copolymer of N‐isopropylacrylamide (NIPAAm), ruthenium‐complex (Ru(bpy)3), and N‐succinimidyl acrylic acid (NAS) was synthesized to investigate its selfoscillating properties in a solution. This polymer exhibits selfoscillation in turbidity and viscosity synchronized via a Belousov–Zhabotinsky (BZ) reaction. The molecular size of the polymer during oscillation was investigated by dynamic light scattering and electrochemical measurements. Both molecular size and viscosity exhibited periodic changes during the BZ reaction. A simple mechanism accounting for such periodic changes was investigated by numerical calculations. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1578–1588, 2007  相似文献   

17.
Temperature‐induced phase separation of poly(N‐isopropylacrylamide) in aqueous solutions was studied by attenuated total reflectance (ATR)/Fourier transform infrared spectroscopy. The main objectives of the study were to understand, on a molecular level, the role of hydrogen bonding and hydrophobic effects below and above the phase‐separation temperature and to derive the scenario leading to this process. Understanding the behavior of this particular system could be quite relevant to many biological phenomena, such as protein denaturation. The temperature‐induced phase transition was easily detected by the ATR method. A sharp increase in the peaks of both hydrophobic and hydrophilic groups of the polymer and a decrease in the water‐related signals could be explained in terms of the formation of a polymer‐enriched film near the ATR crystal. Deconvolution of the amide I and amide II peaks and the O? H stretch envelope of water revealed that the phase‐separation scenario could be divided, below the phase‐separation temperature, into two steps. The first step consisted of the breaking of intermolecular hydrogen bonds between the amide groups of the polymer and the solvent and the formation of free amide groups, and the second step consisted of an increase in intramolecular hydrogen bonding, which induced a coil–globule transition. No changes in the hydrophobic signals below the separation temperature could be observed, suggesting that hydrophobic interactions played a dominant role during the aggregation of the collapsed chains but not before. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 1665–1677, 2001  相似文献   

18.
In the present study, a new (E)‐rich‐enyne π‐conjugated polymer containing a carbazole was designed and synthesized. Two different synthesis methods of poly[N‐(2‐ethylhexyl)‐3,6‐carbazolyleneethynylene‐(E)‐vinylene] (PCZEV) have been prepared from 3,6‐diethynyl‐9(2‐ethylhexyl)carbazole by using the palladium‐carbene‐catalyzed reaction and/or by using the organolanthanide‐catalyzed reaction leading to well‐defined polymer, and their general properties were studied. Compared to poly[N‐(2‐ethylhexyl)‐3,6‐carbazolyleneethynylene] (PCE), the UV‐vis absorption and photoluminescence of the PCZEV was red‐shifted, which indicates the extension of conjugation length. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2434–2442, 2009  相似文献   

19.
Metal‐free ring‐opening oligomerization of glycidyl phenyl ether (GPE) initiated with tetra‐n‐butylammonium fluoride (n‐Bu4NF) (5.0 mol %) was performed in the presence of poly(ethylene glycol) monomethyl ether (PEGM) (5.0, 10, 20 mol %) as a chain transfer agent, by which the resulting polymers having narrow molecular weight distribution (Mw/Mn < 1.2) were obtained in 80–84% yield. Solubility of the obtained polymers in water increased with the increase of amount of PEGM, owing to an increase of number of PEGM‐block‐oligo(GPE) molecules compared to that of oligo(GPE) molecules having FCH2– group at the initiating end as well as a decrease in degree of oligomerization of oligo(GPE). The PEGM‐block‐oligo(GPE) was isolated by filtration of the polymer aqueous solution, whose number‐average molecular weights determined by NMR spectroscopic analysis were almost consistent to the theoretical values. The PEGM‐block‐oligo(GPE) formed micelles in aqueous media, whose average particle diameter was 58 and 140 nm for the copolymers having a composition of PEGM:GPE = 62:38 and 53:47, respectively. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 4451–4458  相似文献   

20.
Four generations of new amphiphilic thermoresponsive linear‐dendritic block copolymers (LDBCs) with a linear poly(N‐vinylcaprolactam) (PNVCL) block and a dendritic poly(benzyl ether) block are synthesized by atom transfer radical polymerization (ATRP) of N‐vinylcaprolactam (NVCL) using dendritic poly(benzyl ether) chlorides as initiators. The copolymers have been characterized by 1H NMR, FTIR, and GPC showing controlled molecular weight and narrow molecular weight distribution (PDI ≤ 1.25). Their self‐organization in aqueous media and thermoresponsive property are highly dependent on the generation of dendritic poly(benzyl ether) block. It is observed for the LDBCs that the self‐assembled morphology changes from irregularly spherical micelles, vesicles, rod‐like large compound vesicles (LCVs), to the coexistence of spherical micelles and rod‐like LCVs, as the generation of the dendritic poly(benzyl ether) increases. The results of a cytotoxicity study using an MTT assay method with L929 cells show that the LDBCs are biocompatible. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 300–308  相似文献   

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