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1.
Condensations of cyclohexanedimethanol derivatives with tetraethyl orthosilicate in the proper stoichiometric ratio produce crosslinked poly(orthosilicate)s. Synthesized crosslinked polymers have swelling abilities in common organic solvents such as tetrahydrofuran (THF), dichloromethane, benzene and acetone. All these polymers are moderately thermally stable and possess solvent uptake abilities that are not only good and fast but are also regenerable. FTIR, solid‐state 13C, 29Si‐NMR and thermal methods were used to characterize these synthesized polymers. The effects of different cyclohexanedimethanol derivatives on the properties of polymers were also examined. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci 122:1182–1189, 2011  相似文献   

2.
Phenylene-bridged cross-linked poly(alkoxysilane)s produced by the condensation of 1,4-bis(triethoxysilyl) benzene (BTEB) with different lengths of aliphatic diols in proper stoichiometric ratios were successfully prepared. The synthesized phenylene-bridged poly(alkoxysilane)s were characterized by Fourier transform infrared spectroscopy (FTIR), solid-state 13C and 29Si cross polarization magic angle spinning nuclear magnetic resonance (CP-MAS NMR), and thermal gravimetric analysis (TGA). The oil and organic solvent uptake capacity, reusability, absorption and desorption kinetics of cross-linked polymers were examined. The effect of chain length of the linear diol monomers on the polymer-solvent interaction was also investigated. The swelling experiments were conducted in oils such as gasoline, euro diesel and organic solvents such as dichloromethane, tetrahydrofuran, benzene and toluene. All the synthesized polymers have high and fast swelling properties in oils and organic solvents. The reutilize properties of polymer in organic solvents were also investigated.  相似文献   

3.
Cross‐linked poly(orthocarbonate)s were prepared by condensation of the tetraethyl orthocarbonate with different length of aliphatic diols. The synthesized polymers have been characterized by Fourier‐transform infrared spectroscopy, solid‐state 13C cross‐polarization magic angle spinning (CPMAS) nuclear magnetic resonance, thermal gravimetric analysis, and elemental analysis. The cross‐linked polymers were evaluated for organic solvent absorbency application. The effect of diol type on swelling properties of cross‐linked polymers was studied through the solvent absorption tests. The swelling parameters such as maximum solvent absorbency, saturation time, and retention of the solvent were evaluated for the synthesized sorbents. All of the cross‐linked polymers had moderate thermal stability and good regenerable solvent uptake abilities. POLYM. ENG. SCI., 53:2102–2108, 2013. © 2013 Society of Plastics Engineers  相似文献   

4.
A novel type of biphenyl‐bridged alkoxysilane‐based crosslinked polyalkoxysilane was prepared by the condensation of 4,4′‐bis(triethoxysilyl)?1,1′‐biphenyl and different lengths of linear aliphatic diols. Fourier transform infrared spectroscopy, solid‐state 13C and 29Si cross‐polarization magic angle spinning nuclear magnetic resonance, and thermogravimetric analysis were used to characterize the biphenyl‐bridged, crosslinked polyalkoxysilanes. The crosslinked polymers were found to have very quick and high swelling capabilities in organic solvents and oils. The absorption–desorption kinetics and reusability features of the crosslinked polymers were also studied, and we found that the synthesized polymers reached their maximum absorption capacity during a variety of tests without losing capacity. We also tested the absorption performance of the sorbents from water surfaces. All of these results confirm that biphenyl‐bridged, crosslinked polyalkoxysilanes could be good candidates as sorbent materials for the cleaning of water from organic contaminants. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44193.  相似文献   

5.
A series of photosensitive poly(ether–ester)s containing α,β‐unsaturated ketone moieties in the main chain were synthesized from 2,6‐bis[4‐(3‐hydroxypropyloxy)‐3‐methoxybenzylidene]cyclohexanone (BHPMBCH) and aliphatic and aromatic diacid chlorides. The diol precursor, BHPMBCH, was synthesized from 2,6‐bis(4‐hydroxy‐3‐methoxybenzylidene)cyclohexanone and 3‐bromo‐1‐propanol. The solubility of the polymers was tested in various solvents. The intrinsic viscosity of the synthesized polymers, determined by an Oswald viscometer, was found to be 0.06–0.80 g/dL. The molecular structures of the monomer and polymers were confirmed by Fourier transform infrared, ultraviolet–visible, 1H‐NMR, and 13C‐NMR spectral analyses. The thermal properties were studied with thermogravimetric analysis and differential scanning calorimetry. The thermogravimetric analysis data revealed that the polymers were stable up to 220°C and started degrading thereafter. The thermal stability initially increased with increasing spacer length and then decreased due to negative effects of the spacer. The self‐extinguishing properties of the synthesized polymers were studied by the determination of the limiting oxygen index values with Van Krevelen's equation. In addition, the photocrosslinking properties of the polymer chain were studied with UV spectroscopy, and we observed that the rate of photocrosslinking increased significantly with increasing methylene carbon chain length of the acid spacer. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

6.
A new series of homo‐ and copolyphosphoramide esters containing pendant chlorine group was synthesized from dihydroxy chalcones, N‐(4‐chlorophenyl)phosphoramidic dichloride, and terephthaloyl chloride by interfacial polycondensation technique. The diol monomers were prepared by condensing 4‐hydroxy benzaldehyde and 3‐methoxy‐4‐hydroxybenzaldehyde with 4‐hydroxy acetophenone. The synthesized monomers and polymers were characterized by UV, IR and 1H, 13C, and 31PNMR spectroscopic techniques. Molecular weight of the polymers was determined by gel permeation chromatography. The thermal properties of the polymers were studied by thermogravimetric analysis and differential scanning calorimetry under nitrogen atmosphere. The photo‐crosslinking ability of the polymers in various solvents was observed with UV spectrophotometer. The photocrosslinking proceeds via 2π +2π cycloaddition reaction of α, β‐unsaturated carbonyl group. The comparison study on the rate of photocrosslinking of homo and copolymers was also carried out. The chemical and physical properties of these polyesters are compared with those of the unsubstituted polyesters and the results are discussed herein. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

7.
Novel biodegradable chemically crosslinked polymers, poly(5‐hydroxylevulinic acid‐co‐α,ω‐diol)s (PHLA‐diols), were synthesized from 5‐hydroxylevulinic acid and α,ω‐diols and characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, and dynamic mechanical analysis. The gel content, swelling ratio, tensile properties, and hydrolytic degradation behaviors were also measured and assessed. The glass‐transition temperature of the PHLA‐diols could be adjusted within a wide range (?50 to 30°C) by the type and feed ratio of the diol. Because of the low glass‐transition temperature and crosslink structure, they exhibited certain elastic properties. The tensile modulus, strength, and elongation at break measured at 37°C were 1.4–6.3 MPa, 0.8–1.6 MPa, and 10–25%, respectively. These polymers could be hydrolytically degraded. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

8.
A novel dinaphthodioxocin‐containing diol monomer, 8,16‐methano‐16H‐dinaphtho[2,1‐d:1′,2′‐g][1,3] dioxocin‐2,14‐diol (MDDD) was synthesized in high yield and purity through the condensation of 2,7‐dihydroxynaphthalene with malonaldehydetetramethyl acetal at room temperature. It is used as a new monomer for the synthesis of a series of novel dinaphthodioxocin‐containing aliphatic polyesters by interfacial polycondensation method. The new diol monomer was fully characterized by IR, NMR, mass spectroscopies, and elemental analysis. Optimal conditions for polyesterification were obtained via study of the model compounds. Polyesters derived from MDDD and four aliphatic diacid chlorides had inherent viscosities ranging from 0.26 to 0.38 dL/g. The chemical structure of the polymers was fully characterized by IR, NMR spectroscopies, and elemental analysis. The physical properties of the polymers were studied. All the new polymers show good thermal stability and very good solubility in most organic solvents. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

9.
Thermoplastic polyurethane elastomers (TPUs) are now widely used because of their excellent properties that include high tensile and tear strength, and good abrasion, impact and chemical resistance. TPUs are multiblock copolymers with alternating sequences of hard segments composed of diisocyanates and simple diols (chain extenders) and soft segments formed by polymer diols. Commonly used hard segments for TPUs are derived from 4,4′‐diphenylmethane diisocyanate (MDI) and aliphatic diols. The aim of our research was to examine the possibility of obtaining TPUs with good tensile properties and thermal stability by using an unconventional aliphatic‐aromatic chain extender, containing sulfide linkages. Three series of novel TPUs were synthesized by melt polymerization from poly(oxytetramethylene) diol, poly(ε‐caprolactone) diol or poly(hexane‐1,6‐diyl carbonate) diol of number‐average molecular weight of 2000 g mol?1 as soft segments, MDI and 3,3′‐[methylenebis(1,4‐phenylenemethylenethio)]dipropan‐1‐ol as a chain extender. The structure and basic properties of the polymers were examined using Fourier transfer infrared spectroscopy, X‐ray diffraction, atomic force microscopy, differential scanning calorimetry, thermogravimetric analysis, Shore hardness and tensile tests. It is possible to synthesize TPUs from the aliphatic‐aromatic chain extender with good tensile properties (strength up to 42.6 MPa and elongation at break up to 750%) and thermal stability. Because the structure of the newly obtained TPUs incorporates sulfur atoms, the TPUs can exhibit improved antibacterial activity and adhesive properties. Copyright © 2011 Society of Chemical Industry  相似文献   

10.
A series of new copolymers with desired thermal stability and mechanical properties for applications in leather industry were synthesized from various substituted maleimides and alkyl acrylates. Polymerization was carried out by a free‐radical polymerization using benzoyl peroxide (BPO) as initiator. The monomers and polymers synthesized were characterized by elemental analysis, IR, and nuclear magnetic resonance (NMR). Interestingly, these polymers were soluble in common organic solvents. Copolymer composition and reactivity ratios were determined by 1H‐NMR spectra. The molecular weights of the polymers were determined by gel permeation chromatography. The homo‐ and copolymer of maleimide showed single‐stage decomposition (ranging from 300–580°C). The initial decomposition temperatures of poly[N‐(phenyl)maleimide] [poly(PM)], poly[N‐4‐(methylphenyl)maleimide] [poly(MPM)] and poly[N‐3‐(chlorophenyl)maleimide] [poly(CPM)] were higher compared to those of the copolymers. Heat‐resistant adhesives such as blends of epoxy resin with phenyl‐substituted maleimide‐co‐glycidyl methacrylate copolymers with improved adhesion property were developed. Different adhesive formulations of these copolymaleimides were prepared by curing with diethanolamine at two different temperatures (30°C and 60°C). © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 1870–1879, 2001  相似文献   

11.
Crosslinked polyorthocarbonates were synthesized by the condensation of tetraethyl orthocarbonate and hydroxyl functional monomers. The main goal of this study was to produce a solvent‐absorbent polymer with a high absorption capacity and to use these polymers for the removal of organic solvents from the environment and the recovery of these solvents. The synthesized polymers were characterized by Fourier transform infrared spectroscopy, solid‐state 13C‐NMR spectroscopy, thermogravimetric analysis, and differential scanning calorimetry. All of the polymers (except Poly 1 and Poly 2 ) had a high and fast uptake ability for organic solvents, such as tetrahydrofuran, dichloromethane, benzene, and acetone. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

12.
Three novel diamine monomers ( VI , VII , and VIII ) were synthesized. These diamine monomers lead to a number of semifluorinated poly(ether imide)s when reacted with different commercially available dianhydrides like pyromellitic dianhydride (PMDA), benzophenone tetracarboxylic acid dianhydride (BTDA), 2,2‐bis (3,4‐dicarboxyphenyl) hexafluoropropene (6FDA), and oxydiphthalic dianhydride (ODA) by thermal imidization route. Elemental analyses, IR and NMR techniques were used to characterize the monomers and polymers. The resulting polymers exhibited weight average molar masses up to 1.78 × 105 g mol?1 in GPC with respect to polystyrene standard and have very good solubility in several organic solvents such as NMP, DMF, DMAC, DMSO, chloroform, and THF. Very good solubility of these polymers in CDCl3 enables their complete characterization by proton as well as 13C‐NMR techniques. The polymers showed very high thermal stability with decomposition temperature (5% weight loss) up to 511°C in air and high glass transition temperature up to 311°C depending upon the exact repeating unit structure. The polymer films showed high modulus (up to 2.9 GPa) as was evaluated by DMA. The polymers also showed very low water absorption (0.16%), low dielectric constant (2.35 at 1MHz) and very good optical transmission. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3025–3044, 2007  相似文献   

13.
A series of novel aromatic and aromatic–aliphatic diamines [isophthaloyl bis(3‐(3‐aminophenyl)thiourea), terephthaloyl bis(3‐(3‐aminophenyl)thiourea), adipoyl bis(3‐(3‐aminophenyl)thiourea), sebacoyl bis(3‐(3‐aminophenyl)thiourea)] were synthesized starting from the dinitro compounds. Spectroscopic and elemental analyses were carried out for the structure elucidation of the monomers. Three series of poly(thiourea‐amide)s (PTAMs) bearing C?S groups were prepared through the condensation of new diamines with the diacid chlorides such as isophthaloyl, terephthaloyl and adipoyl chloride. The ensuing PTAMs were characterized using FTIR, 1H‐NMR and 13C‐NMR techniques. Physical properties of the polymers such as solution miscibility, crystallinity, solution viscosity, molecular weight, and thermal properties were measured. Consequently, good organosolubility of these polymers was experiential in amide solvents as DMAc, DMF, DMSO and NMP. Moreover, PTAMs exhibited ηinh in the range of 0.92–1.56 dL/g and GPC measurements revealed Mw around 607 × 102‐851 × 102. DSC served to envisage the glass transition temperatures (Tg) of poly(thiourea‐amide)s located between 232 and 258°C and the initial decomposition temperatures (T0) probed by thermogravimetry were in the range of 305–419°C. Structure‐property relationship of these polymers was also studied. Eventually, solid?liquid extraction tests of the selected poly(thiourea‐amide)s systems revealed excellent results because these polymers show nearly 100% elimination of lead and mercury cations from water media. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

14.
A series of shape‐memory polyurethanes based on poly(ϵ‐caprolactone) diol were prepared with novel hydroxyl‐terminated hyperbranched polyurethanes as crosslinkers and were characterized by Fourier transform infrared spectroscopy, 1H‐NMR, gel permeation chromatography, differential scanning calorimetry, scanning electron microscopy, wide‐angle X‐ray diffraction, dynamic mechanical analysis, tensile testing, and shape‐memory testing. The molecular weight of the soluble polymers ranged from 5.1 × 104 to 29.0 × 104 g/mol. The differential scanning calorimetry and wide‐angle X‐ray diffraction data indicated that when the crystallinities of the crosslinked polymers were compared to that of linear polyurethane, this parameter was improved when the crosslinker was in low quantity. The storage modulus ratios obtained from the dynamic mechanical analyses data of the crosslinked polymers were also high compared to that of the linear polyurethane. As a result, crosslinked polymers showed better shape‐memory properties compared to the linear polyurethanes. Also, the that incorporation of the hyperbranched polymer as a crosslinker into the polyurethane chain improved the thermal and mechanical properties of the polymer. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

15.
A crosslinker and crosslinkable sulfonated poly(arylene ether)s with trifluorovinyl ether groups were synthesized via reaction of 4‐trifluorovinyloxyphenol for application in fuel cells. Crosslinked poly(arylene ether) membranes were prepared by thermal irradiation, and the cyclodimerization of the trifluorovinyl ether groups in the polymers as well as the crosslinker was confirmed using differential scanning calorimetry and infrared measurements. These crosslinked membranes showed a low swelling ratio, comparable to that of Nafion 112. The proton conductivity of the crosslinked membranes was 0.17 and 0.3 S cm?1 at 30 and 80 °C, respectively, much higher than that of Nafion 112 under the same conditions. The excellent dimensional stability and high conductivity of the crosslinked membranes can be attributed to this new type of crosslinking system (end‐group crosslinking) as well as the chemical structure of crosslinked (multi‐block) polymers. Copyright © 2011 Society of Chemical Industry  相似文献   

16.
A new family of biodegradable amino acid-based poly(ether ester amide)s (AA-PEEAs) consisting of three building blocks [poly(ε-caprolactone) (PCL), L -phenylalanine (Phe), and aliphatic acid dichloride] were synthesized by a solution polycondensation. Using DMA as the solvent, these PCL-containing Phe-PEEA polymers were obtained with fair to very good yields with weight average molecular weight (Mw) ranging from 6.9 kg/mol to 31.0 kg/mol, depending on the original molecular weight of PCL. The chemical structures of the PCL-containing Phe-PEEA polymers were confirmed by IR and NMR spectra. These PCL-containing Phe-PEEAs had lower Tg than most of the oligoethylene glycol (OEG) based AA-PEEAs due to the more molecular flexibility of the PCL block in the backbones, but had higher Tg than non-amino acid based PEEA. The solubility of the PCL-containing Phe-PEEA polymers in a wide range of common organic solvents, such as THF and chloroform, was significantly improved when comparing with aliphatic diol based poly(ester amide)s and OEG based AA-PEEAs. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

17.
Compound 5 a ,10 b ‐dihydrobenzofuro[2,3‐ b ]benzofuran‐2,9‐dicarbaldehyde ( II ) was prepared by two‐step reactions from p‐cresol and glyoxal. The bis(cyanoacetate) monomers ( III ) were prepared in a high yield by reacting ethyl cyanoacetate with the appropriate diol in the presence of tetra‐n‐butyl titanate. The polymers from II and III were synthesized by Knoevenagel polycondensation that was first carried out in anhydrous THF and followed by a solid‐state polycondensation, and main‐chain polymers with good glass transition temperatures in high yield were obtained. The polymerization of II and III afforded polymers IV , which exhibited good solubility in most organic solvents. The structure of all the monomers and polymers were characterized by conventional spectroscopic methods. The synthesized polymers contain acceptor groups (cyanide and carbonyl) and a donor group (benzodihydrofuran) in their main chain. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 505–511, 2001  相似文献   

18.
Environmentally friendly organocatalytic synthesis of aliphatic polyesters was studied. The catalysis investigated is novel, and lends itself well to the potential production of valuable biodegradable products. The reactions were based on an organic acids‐catalyzed ring‐opening polymerization of ε‐caprolactone with fatty acid derivatives as the initiator and were performed in the absence of solvents. The chemical structures of the functionalized polymers were confirmed by 1H and 13C‐NMR spectra. Polymers with different molecular weights, in the range 10,900–15,200 were obtained in the presence of fumaric acid as catalyst. The thermal properties of the functionalized PCLs were determined by modulated differential scanning calorimetry and thermogravimetric analysis. The MDSC results verified that the crystallinity and the melting point of the lipid‐functionalized polymers were lower than that of the unfunctionalized poly(ε‐caprolactone). The hydrolytic degradation of the functionalized polymer was also investigated. The result shows the degradation rate was affected by the presence of oleic acid derivatives in the polymer molecule. The lipid‐functionalized polymers synthesized by the metal‐free polymerization systems seem to be suitable biodegradable polyesters for use in biomedical and pharmacological applications. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

19.
Poly(benzyl ether)‐b‐polystyrene dendritic–linear polymers were successfully synthesized using a dendritic chloric poly(benzyl ether) (G1‐Cl, G2‐Cl, and G3‐Cl) as the macroinitiator through the atom transfer radical polymerization process. The structure and properties of the resultant polymers were characterizated by gel permeation chromatography, 1H‐NMR, Fourier transform IR, thermogravimetric analysis, and differential scanning calorimetry. It was found that the temperature, reaction time, molar ratio of the macroinitiator to styrene, and the generation number of the macroinitiator have significant effects on the molecular weights, conversion, and polydispersities of the resulting polymers. These dendritic–linear block polymers had very good solubility in common organic solvents at room temperature. The terminal group (dendritic segments) of the polymers can affect their thermal stability. These dendritic–linear polymers after self‐assembling in selective solvents (chloroform/acetone) formed core–shell micelles. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1106–1112, 2005  相似文献   

20.
Star‐shaped molecules consisting of regioregular poly(3‐hexylthiophene) (P3HT) chains as the arms, attached to either a propeller‐like triphenylamine or a planar triphenylbenzene core, have been synthesized via Suzuki coupling. The structures of the three‐arm star‐shaped poly(3‐hexylthiophene) (s‐P3HT) materials obtained were studied using Fourier transform infrared, 1H and 13C NMR, XRD, gel permeation chromatography and DSC. The s‐P3HT polymers were soluble in common organic solvents and exhibited number‐average molecular weights of 6000–7200 g mol?1. Their optical properties in solutions and in solid state films were investigated using the UV?visible absorption and photoluminescence techniques, and were compared with those of linear P3HT. © 2015 Society of Chemical Industry  相似文献   

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