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1.
Novel aliphatic aminimides were synthesized from the corresponding carboxylic acid esters, 1,1‐dimethylhydrazine, and epoxides in 54–95% yields. Bulk polymerization of glycidyl phenyl ether (GPE) with 3 mol % of the aminimides was evaluated by DSC as a model process for curing of epoxy resin. All the aminimides showed no exothermic DSC peak below 120 °C but showed sharp exothermic peaks above 137 °C, indicating good thermal latency. Good relationships were observed between the calculated bond length from the carbonyl carbon to the α‐carbon of the aliphatic group (R C), DSC onset temperatures, and the thermal dissociation temperatures (Td 's) of the aminimides. The aminimide with a longer R C bond length showed lower Td and DSC onset temperature, that is, higher activity. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 3428–3433, 2000  相似文献   

2.
The reaction of glycidyl phenyl ether (GPE) with 1‐aminoalkanes‐intercalated α‐zirconium phosphate (α‐ZrP·1‐aminoalkane): 1‐aminoalkanes 1‐aminopropane (α‐ZrP·Pr), 1‐aminobutane (α‐ZrP·Bu), 1‐aminooctane (α‐ZrP·Oct), and 1‐aminohexadecane (α‐ZrP·Hed) was carried out at varying temperatures for 1 h periods. Reaction progress was not observed until the reactants were heated to 80 °C or above. On increasing the temperature, the conversion factors increased such that, at 140 °C, conversions of 62% (α‐ZrP·Pr), 60% (α‐ZrP·Bu), 67% (α‐ZrP·Oct), and 64% (α‐ZrP·Hed) were obtained. The thermal stabilities as latent initiators were tested: GPEs reacted with α‐ZrP·Pr, α‐ZrP·Bu, and α‐ZrP·Oct at 40 °C for 360 h achieved conversions of 83, 55, and 59%, respectively. In contrast, the reaction in the presence of α‐ZrP·Hed did not proceed at 40 °C. The order of the thermal stability of GPE in the presence of α‐ZrP·1‐aminoalkane intercalation compounds was: α‐ZrP·Hed > α‐ZrP·Bu ≈ α‐ZrP·Oct > α‐ZrP·Pr. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1854–1861  相似文献   

3.
Biodegradable polymers provide an attractive solution to reduce environmental pollution caused by the accumulation of plastic waste in landfills. In this study, the effect of polyethylene‐graft‐glycidyl methacrylate (PE‐g‐GMA) on the biodegradation of blends of poly(ε‐caprolactone) (PCL) and cellulose acetate (CA) (80/20, 60/40, 40/60, and 20/80 PCL/CA, w/w) was assessed by mass retention, tensile strength, and morphological properties. The principal fungal strains present in the soil after biodegradation were also identified. PCL and the blends containing 60% and 80% PCL showed greater mass loss and superficial change in simulated soil. PE‐g‐GMA increased the tensile strength retention during 3 months of aging in simulated soil. Scanning electron microscopy (SEM) indicated that pure PCL was more porous, which enhanced the hydrolysis and biodegradation of PCL. PE‐g‐GMA decreased the mass loss of the polymers, possibly by enhancing the interaction between PCL and CA, with the formation of hydrogen bonds between the carbonyl groups of PCL and the hydroxyl groups of CA. This effect was marked in blends with >40% PCL. Microbiological analysis revealed the presence of several species of fungi in the soil. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

4.
A novel series of colorless and highly organosoluble poly(ether imide)s were prepared from 3,3‐bis[4‐(3,4‐dicarboxyphenoxy)phenyl]phthalide dianhydride with various fluorinated aromatic bis(ether amine)s via a conventional two‐stage process that included ring‐opening polyaddition to form the poly(amic acid)s followed by cyclodehydration to produce the polymer films. The poly(ether imide)s showed excellent solubility, with most of them dissoluble at a concentration of 10 wt % in amide polar solvents, in ether‐type solvents, and even in chlorinated solvents. Their films had a cutoff wavelength between 358 and 373 nm, and the yellowness index ranged from 3.1 to 9.5. The glass‐transition temperatures of the poly(ether imide) series were recorded between 237 and 297 °C, the decomposition temperatures at 10% weight loss were all above 494 °C, and the residue was more than 54% at 800 °C in nitrogen. These films showed high tensile strength and also were characterized by higher solubility, lighter color, and lower dielectric constants and moisture absorption than an analogous nonfluorinated polyimide series. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3140–3152, 2006  相似文献   

5.
This work deals with the design, synthesis, in silico analysis, crystallization, and the interpretation 2‐cyano‐3‐{4‐[2‐(phthalimid‐nyl)‐propoxy]‐phenyl}‐acrylic acid ethyl ester (7). Analog 7 is designed based on rosiglitazone. The quantitative analysis of Compound 7 has been performed through single‐crystal X‐Ray Diffraction (XRD) and Hirshfeld surface analysis. Fleximer 7 has studied the role of flexibility in non‐covalent interactions and binding affinity with PPAR‐γ receptors. Both phthalimide ring and phenyl rings are linked with propylene linker. 2‐cyano‐3‐{4‐[2‐(phthalimid‐nyl)‐propoxy]‐phenyl}‐acrylic acid ethyl ester has Z = 8 in the crystal packing and stabilized by intermolecular non‐covalent interactions like C? H…O, C? H…N, C? H…л, and л…л, and so forth.  相似文献   

6.
A new bis(ether anhydride), 3,3′,5,5′‐tetramethyl‐2,2‐bis[4‐(4‐dicarboxyphenoxy)phenyl]propane dianhydride ( 3 ), was prepared in three steps: the nitro displacement of 4‐nitrophthalonitrile with 2,2‐bis(4‐hydroxy‐3,5‐dimethylphenyl)propane, the alkaline hydrolysis of the intermediate bis(ether dinitrile), and the subsequent dehydration of the resulting bis(ether diacid). A series of new highly soluble poly(ether imide)s with tetramethyl and isopropylidene groups were prepared from the bis(ether anhydride) 3 with various diamines by a conventional two‐stage synthesis including polyaddition and chemical cyclodehydration. The resulting poly(ether imide)s had inherent viscosities of 0.54–0.73 dL g?1. Gel permeation chromatography measurements revealed that the polymers had number‐average and weight‐average molecular weights of up to 54,000 and 124,000, respectively. All the polymers showed typical amorphous diffraction patterns. All of the poly(ether imide)s showed excellent solubility and were readily dissolved in various solvents such as N‐methyl‐2‐pyrrolidinone, N,N‐dimethylacetamide, N,N‐dimethylformamide, pyridine, cyclohexanone, tetrahydrofuran, and even chloroform. Most of the polymers could be dissolved with chloroform concentrations as high as 30 wt %. These polymers had glass‐transition temperatures of 244–282 °C. Thermogravimetric analysis showed that all polymers were stable, with 10% weight losses recorded above 463 °C in nitrogen. These transparent, tough, and flexible polymer films were obtained through solution casting from N,N‐dimethylacetamide solutions. These polymer films had tensile strengths of 81–102 MPa and tensile moduli of 1.8–2.0 GPa. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2556–2563, 2002  相似文献   

7.
A bis(ether anhydride) monomer, 1,1‐bis[4‐(3,4‐dicarboxyphenoxy)phenyl]cyclohexane dianhydride ( IV‐A ), was synthesized from the nitro displacement of 4‐nitrophthalodinitrile by the phenoxide ion of 1,1‐bis(4‐hydroxyphenyl)cyclohexane ( I‐A ), followed by alkaline hydrolysis of the intermediate bis(ether dinitrile) and dehydration of the resulting bis(ether acid). A novel series of organosoluble poly(ether imide)s ( VI a–i )(PEIs) bearing cyclohexylidene cardo groups was prepared from the bis(ether anhydride) IV‐A with various aromatic diamines V a–i via a conventional two‐stage process. The PEIs had inherent viscosities in the range of 0.48–1.02 dL/g and afforded flexible and tough films by solution‐casting because of their good solubilities in organic solvents. Most PEIs showed yield points in the range of 89–102 MPa at stress‐strain curves and had tensile strengths of 78–103 MPa, elongations at breaks of 8–62%, and initial moduli of 1.8–2.2 GPa. The glass‐transition temperatures (Tg's) of these PEIs were recorded between 200–234 °C. Decomposition temperatures of 10% weight loss all occurred above 490 °C in both air and nitrogen atmospheres, and their residues were more than 43% at 800 °C in nitrogen atmosphere. The cyclohexane cardo‐based PEIs exhibited relatively higher Tg's, better solubilities in organic solvents, and better tensile properties as compared with the corresponding Ultem® PEI system. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 788–799, 2001  相似文献   

8.
On the line of a previous work on the spectral properties of some of heteroaryl chalcone, the effect of medium acidity and photoreactivity of 3‐(4‐dimethylamino‐phenyl)‐1‐(2,5‐dimethyl‐thiophen‐3‐yl)‐propenone (DDTP) has been investigated in dimethylformamide and in chloromethane solvents such as methylenechloride, chloroform and carbon tetrachloride. The dye solution (ca. 5×10−4 mol·L−1 in DMF) gives a good laser emission in the range 470–560 nm with emission maximum at 515 nm upon pumping by nitrogen laser (λex=337.1 nm). The laser parameters such as gain coefficient (α), emission cross section (δe) and half life energy (E1/2) at maximum laser emission are also determined.  相似文献   

9.
Bulk nitroxide‐mediated polymerization (NMP) of β‐myrcene (My)/glycidyl methacrylate (GMA) mixtures with varying GMA molar feed fraction (fGMA,0 = 0.10–0.91) was accomplished at 120 °C, initiated by SG1‐based alkoxyamine bearing a N‐succinimidyl ester group (NHS‐BlocBuilder). Low dispersity My/GMA copolymers (Đ < 1.56) with slight number‐average molecular weights (Mns) deviations from predicted values (Mn,theo with Mn/Mn,theo > 70%) were obtained. The copolymerization was revealed to be statistical, confirmed via Fineman–Ross (rMy = 0.80 ± 0.31 and rGMA = 0.71 ± 0.15) and Kelen‐Tüdös (rMy = 0.48 ± 0.12 and rGMA = 0.53 ± 0.18) approaches. Glass transition temperature (Tg) of the statistical P(Mystat‐GMA)s increased from −77 to +43 °C as the GMA molar fraction incorporated (FGMA) increased from 0.10 to 0.90. High SG1 chain‐end fidelity for My‐rich and GMA‐rich P(Mystat‐GMA)s was assessed by phosphorus nuclear magnetic resonance (31P NMR, SG1 fraction >69 mol %) and chain‐extensions in toluene with My, GMA and styrene (S) (monomodal shift in Mn). Last, diblock P(Myb‐GMA) was made and treated with morpholine to produce amphiphilic copolymer able to self‐organize into micelles. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 860–878  相似文献   

10.
A novel two‐dimensional CoII coordination framework, namely poly[(μ2‐biphenyl‐4,4′‐diyldicarboxylato‐κ2O4:O4′){μ2‐bis[4‐(2‐methyl‐1H‐imidazol‐1‐yl)phenyl] ether‐κ2N3:N3′}cobalt(II)], [Co(C14H8O4)(C20H18N4O)]n, has been prepared and characterized by IR, elemental analysis, thermal analysis and single‐crystal X‐ray diffraction. The crystal structure reveals that the compound has an achiral two‐dimensional layered structure based on opposite‐handed helical chains. In addition, it exhibits significant photocatalytic degradation activity for the degradation of methylene blue.  相似文献   

11.
A microwave‐assisted extraction (MAE) protocol and an efficient HPLC analysis method were first developed for the fast extraction and simultaneous determination of bisphenol F diglycidyl ether (Novolac glycidyl ether 2‐Ring), Novolac glycidyl ether 3‐Ring, Novolac glycidyl ether 4‐Ring, Novolac glycidyl ether 5‐Ring, Novolac glycidyl ether 6‐Ring, bisphenol A diglycidyl ether, bisphenol A (2,3‐dihydroxypropyl) glycidyl ether, bisphenol A (3‐chloro‐2‐hydroxypropyl) glycidyl ether, bisphenol A bis(3‐chloro‐2‐hydroxypropyl) ether, bisphenol A (3‐chloro‐2‐hydroxypropyl) (2,3‐dihydroxypropyl) ether in canned fish and meat. After being optimized in terms of solvents, microwave power and irradiation time, MAE was selected to carry out the extraction of ten target compounds. Analytes were purified by poly(styrene‐co‐divinylbenzene) SPE columns and determinated by HPLC‐fluorescence detection. LOD varied from 0.79 to 3.77 ng/g for different target compounds based on S/N=3; LOQ were from 2.75 to 10.92 ng/g; the RSD for repeatability were <8.64%. The analytical recoveries ranged from 70.46 to 103.44%. This proposed method was successfully applied to 16 canned fish and meat, and the results acquired were in good accordance with the studies reported. Compared with the conventional liquid–liquid extraction and ultrasonic extraction, the optimized MAE approach gained the higher extraction efficiency (20–50% improved).  相似文献   

12.
The chemoselectivity in the reaction of 2‐diazo‐3‐oxo‐3‐phenylpropanal ( 1 ) with aldehydes and ketones in the presence of Et3N was investigated. The results indicate that 1 reacts with aromatic aldehydes with weak electron‐donating substituents and cyclic ketones under formation of 6‐phenyl‐4H‐1,3‐dioxin‐4‐one derivatives. However, it reacts with aromatic aldehydes with electron‐withdrawing substituents to yield 1,3‐diaryl‐3‐hydroxypropan‐1‐ones, accompanied by chalcone derivatives in some cases. It did not react with linear ketones, aliphatic aldehydes, and aromatic aldehydes with strong electron‐donating substituents. A mechanism for the formation of 1,3‐diaryl‐3‐hydroxypropan‐1‐ones and chalcone derivatives is proposed. We also tried to react 1 with other unsaturated compounds, including various olefins and nitriles, and cumulated unsaturated compounds, such as N,N′‐dialkylcarbodiimines, phenyl isocyanate, isothiocyanate, and CS2. Only with N,N′‐dialkylcarbodiimines, the expected cycloaddition took place.  相似文献   

13.
Four new transition metal complexes: [Cu(Hcppa)2(H2O)2] ( 1 ), [Co2(cppa)2(H2O)10] ( 2 ), [Co3(cpia)2(H2O)8] · 2H2O ( 3 ) and [Ni3(cpia)2(H2O)12] · 6H2O ( 4 ) {H2cppa = 3‐(4‐(carboxymethoxy)phenyl]propanoic acid; H3cpia = N‐[4‐(carboxymethoxy)phenyl]iminodiacetic acid} were synthesized and characterized. Complexes 1 and 2 show mononuclear structures, complexes 3 and 4 exhibit dinuclear structures. All complexes extend to 3D supramolecular networks through hydrogen bonds, of which complexes 3 and 4 display microporous structures. In complexes 2 – 4 the water clusters are trapped by the cooperative association of coordinate interactions as well as hydrogen bonds, forming different 1D metal‐water chain structures. Thermal stabilities of complexes 1 – 4 were discussed.  相似文献   

14.
4‐Chloro‐3‐methyl phenyl methacrylate (CMPM) and 8‐quinolinyl methacrylate (8‐QMA) were synthesized through the reaction of 4‐chloro‐3‐methyl phenol and 8‐hydroxy quinoline, respectively, with methacryloyl chloride. The homopolymers and copolymers were prepared by free‐radical polymerization with azobisisobutyronitrile as the initiator at 70 °C. Copolymers of CMPM and 8‐QMA of different compositions were prepared. The monomers were characterized with IR spectroscopy and 1H NMR techniques. The copolymers were characterized with IR spectroscopy. UV spectroscopy was used to obtain the compositions of the copolymers. The monomer reactivity ratios were calculated with the Fineman–Ross method. The molecular weights and polydispersity values of the copolymers were determined with gel permeation chromatography. The thermal stability of the polymers was evaluated with thermogravimetric analysis under a nitrogen atmosphere. The homopolymers and copolymers were tested for their antimicrobial activity againstbacteria, fungi, and yeast. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 157–167, 2005  相似文献   

15.
We report the synthesis and characterization of well‐defined homo‐ and diblock copolymers containing poly(furfuryl glycidyl ether) (PFGE) via living anionic ring‐opening polymerization using different initiators. The obtained materials were characterized by SEC, MALDI‐TOF MS, and 1H NMR spectroscopy and molar masses of up to 9400 g/mol were obtained for PFGE homopolymers. If the amphiphilic diblock copolymer PEG‐block‐PFGE was dissolved in water, micelles with a PFGE core and a PEG corona were formed. Hereby, the hydrophobic PFGE core domains were used for the incorporation of a suitable bismaleimide and heating to 60 °C induced the crosslinking of the micellar core via Diels‐Alder chemistry. This process was further shown to be reversible. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

16.
A novel (3‐sulfopropyl methacrylate potassium)‐silica hybrid monolithic column for CEC has been prepared by a simple one‐pot approach based on efficient thiol‐ene click chemistry. In this process, the polycondensation of hydrolyzed alkoxysilanes and in situ click reaction of vinyl groups on 3‐sulfopropyl methacrylate potassium and thiol groups on the precondensed siloxanes simultaneously occurred in a pretreated capillary. Homogeneous monolithic matrix with large through‐pores tightly bonded to the inner wall of the capillary was shown by optical microscope and SEM. The minimum plate height of this hybrid monolithic column was determined as 3.9 μm for thiourea. Anilines, alkylbenzenes, and phenols were well separated on this hybrid monolithic column by CEC, which indicated typical reversed‐phase and cation‐exchange chromatographic retention mechanisms of the column.  相似文献   

17.
Hybrid composites consisting of isotactic poly(propylene) (PP), sisal fiber (SF), and maleic anhydride grafted styrene‐(ethylene‐co‐butylene)‐styrene copolymer (MA‐SEBS) were prepared by melt compounding, followed by injection molding. The melt‐compounding torque behavior, thermal properties, morphology, crystal structure, and mechanical behavior of the PP/MA‐SEBS/SF composites were systematically investigated. The torque test, thermogravimetric analysis, differential scanning calorimetric, and scanning electron microscopic results all indicated that MA‐SEBS was an effective compatibilizer for the PP/SF composites, and there was a synergism between MA‐SEBS and PP/SF in the thermal stability of the PP/MA‐SEBS/SF composites. Wide‐angle X‐ray diffraction analysis indicated that the α form and β form of the PP crystals coexisted in the PP/MA‐SEBS/SF composites. With the incorporation of MA‐SEBS, the relative amount of β‐form PP crystals decreased significantly. Mechanical tests showed that the tensile strength and impact toughness of the PP/SF composites were generally improved by the incorporation of MA‐SEBS. The instrumented drop‐weight dart‐impact test was also used to examine the impact‐fracture behavior of these composites. The results revealed that the maximum impact force (Fmax), impact‐fracture energy (ET), total impact duration (tr), crack‐initiation time (tinit), and crack‐propagation time (tprop) of the composites all tended to increase with an increasing MA‐SEBS content. From these results, the incorporation of MA‐SEBS into PP/SF composites can retard both the crack initiation and propagation phases of the impact‐fracture process. These prolonged the crack initiation and propagation time and increased the energy consumption during impact fracture, thereby leading to toughening of PP/MA‐SEBS/SF composites. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 1214–1222, 2002  相似文献   

18.
The synthesis of a new compound, 2‐[(4‐bromomethyl)phenyl]‐4,5‐dihydro‐4,4‐dimethyloxazole ( 1 ), and its utility in the synthesis of oxazoline‐functionalized polystyrene by atom transfer radical polymerization (ATRP) methods are described. Aromatic oxazolyl‐functionalized polymers were prepared by the ATRP of styrene, initiated by ( 1 ) in the presence of copper(I) bromide/2,2′‐bipyridyl catalyst system, to afford the corresponding α‐oxazolyl‐functionalized polystyrene ( 2 ). The polymerization proceeded via a controlled free radical polymerization process to produce the corresponding α‐oxazolyl‐functionalized polymers with predictable number‐average molecular weights, narrow molecular weight distributions in high‐initiator efficiency reactions. Post‐ATRP chain end modification of α‐oxazolyl‐functionalized polystyrene ( 2 ) to form the corresponding α‐carboxyl‐functionalized polystyrene ( 3 ) was achieved by successive acid‐catalyzed hydrolysis and saponification reactions. The polymerization processes were monitored by gas chromatography analyses. The unimolecular‐functionalized initiator and functionalized polymers were characterized by thin layer chromatography, spectroscopy, size exclusion chromatography, and nonaqueous titration analysis. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011.  相似文献   

19.
The catalytic effects of 1,5,7‐Triazabicyclo[4.4.0]dec‐5‐ene (TBD) with 2‐methylimidazole‐intercalated α‐zirconium phosphate (α‐ZrP?2MIm) in the reaction of glycidyl phenyl ether (GPE) and hexahydro‐4‐methylphthalic anhydride (MHHPA) were investigated. The reaction did not proceed within 1 h at 60 °C. On increasing the temperature to 100 °C, the conversion reached 93% for 1 h. Without the addition of TBD, the conversion was 67% at 100 °C for 1 h. Under storage conditions at 25 °C for 7 days, the conversion of GPE was only 18%. The curing behavior of 2,2‐bis(4‐glycidyloxyphenyl)propane (DGEBA) and MHHPA in the presence of TBD with α‐ZrP?2MIm was evaluated by differential scanning calorimetry. The addition of TBD with α‐ZrP?2MIm as a latent thermal initiator, the storage stability was maintained and the reaction proceeded rapidly under heating conditions. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 2557–2561  相似文献   

20.
The effects of radicals on silica surface, which were formed by γ‐ray irradiation, on the polymerization of vinyl monomers were investigated. It was found that the polymerization of styrene was remarkably retarded in the presence of γ‐ray‐irradiated silica above 60 °C, at which thermal polymerization of styrene is readily initiated. During the polymerization, a part of polystyrene formed was grafted onto the silica surface but percentage of grafting was very small. On the other hand, no retardation of the polymerization of styrene was observed in the presence of γ‐ray‐irradiated silica below 50 °C; the polymerization tends to accelerate and polystyrene was grafted onto the silica surface. Poly(vinyl acetate) and poly(methyl methacrylate) (MMA) were also grafted onto the surface during the polymerization in the presence of γ‐ray‐irradiated silica. The grafting of polymers onto the silica surface was confirmed by thermal decomposition GC‐MS. It was considered that at lower temperature, the grafting based on the propagation of polystyrene from surface radical (“grafting from” mechanism) preferentially proceeded. On the contrary, at higher temperature, the coupling reaction of propagating polymer radicals with surface radicals (“grafting onto” mechanism) proceeded to give relatively higher molecular weight polymer‐grafted silica. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2972–2979, 2006  相似文献   

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