首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
This study is aimed at investigating the microbiocidal potential of amino‐functionalized poly(norbornenes) in the solid state. A series of norbornene‐type monomers that carry secondary or tertiary amine functions as well as hexyl and dodecyl groups were prepared. Ring‐opening metathesis polymerization was used to prepare homopolymers of the amine bearing monomers and random copolymers of amine‐ and alkyl‐substituted monomers of high average molar mass. The resulting polymers were characterized by nuclear magnetic resonance, thermogravimetry, differential scanning calorimetry, infrared spectroscopy, and contact angle measurements, and their contact biocidal potential was evaluated according to the Japanese Industry standard Z2801. Tested microorganisms comprised Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Candida albicans, and Aspergillus niger. Microbiocidal activity of selected polymer films against E. coli, S. aureus, and A. niger was found, whereas against C. albicans and P. aeruginosa microbiostatic behavior was observed. Moreover, the most potent copolymer revealed no cytotoxicity rendering a biocidal polymer with potential applications in mammalian‐, and in particular, human‐related fields. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010  相似文献   

2.
The click reaction between azides and alkynes is been increasingly employed in the preparation of polymers. In this article, we describe the synthesis and click polyaddition reaction of a new A‐B‐type amide monomer—prepared from d ‐glucose as renewable resource—containing the alkyne and azide functions. Both Cu(I)‐catalyzed and metal‐free click polymerization methods were used to prepare glucose‐derived poly(amide triazole)s. The resulting polymers had weight‐average molecular weights in the 45,000–129,000 range and were characterized by GPC, IR, and NMR spectroscopies. Thermal and X‐ray diffraction studies revealed them to be amorphous. Their qualitative solubilities in various solvents and their water sorption have been studied. The poly(amide triazole)s having the alcohol functions protected as methyl ether were water‐soluble. The presence of the amide functions along the polymer chain made these polytriazoles degradable in the presence of sodium deuteroxide. The degradation was monitored by NMR analysis, and the degradation product was characterized by HRMS. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 629–638  相似文献   

3.
A vinylphosphonate monomer, dimethyl vinylphosphonate (DMVP), has been polymerized by anionic initiators. Anionic polymerization of DMVP with tert‐butyllithium (t‐BuLi) in combination with a Lewis acid, tributylaluminum (n‐Bu3Al), in toluene proceeded smoothly to give an isotactic‐rich poly(dimethyl vinylphosphonate) (PDMVP) with relatively narrow molecular weight distribution. Although all the PDMVPs were soluble in water, the isotactic‐rich PDMVP was insoluble in acetone and in chloroform which are good solvents for an atactic PDMVP prepared by radical polymerization. The isotactic‐rich PDMVP showed higher thermal property than that of the atactic PDMVP. Moreover, we successfully prepared poly(vinylphosphonic acid) (PVPA) through the hydrolysis of the isotactic‐rich PDMVP, which formed a highly transparent, self‐standing film. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1677–1682, 2010  相似文献   

4.
A method for the preparation of poly(aryl ether thianthrene)s has been developed in which the aryl ether linkage is generated in the polymer‐forming reaction. The thianthrene heterocycle is sufficiently electron‐withdrawing to allow fluoro displacement with phenoxides by nucleophilic aromatic substitution. The monomer for this reaction, 2,7‐difluorothianthrene, can be synthesized in a moderate yield by a simple reaction sequence. Semiempirical calculations at the PM3 level suggest that 2,7‐difluorothianthrene is sufficiently activated, whereas NMR spectroscopy (1H and 13C) indicates that the monomer is only slightly activated or (19F) not sufficiently activated for nucleophilic aromatic substitution. Model reactions with p‐cresol have demonstrated that the fluorine atoms on 2,7‐difluorothianthrene are readily displaced by phenoxides in high yields, and the process has been deemed suitable for polymer‐forming reactions. High‐molecular‐weight polymers have been produced from bisphenol A, bisphenol AF, and 4,4′‐biphenol. The polymers have been characterized with gel permeation chromatography, NMR spectroscopy, differential scanning calorimetry, thermogravimetric analysis, and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry. The glass‐transition temperatures for the polymers of different compositions and molecular weights range from 138 to 181 °C, and all the polymers have shown high thermooxidative stability, with 5% weight loss values in an air environment approaching 500 °C. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 6353–6363, 2004  相似文献   

5.
A series of ABx‐type triarylphosphine oxide monomers, bis‐(4‐fluorophenyl)‐(4‐hydroxyphenyl)phosphine oxide ( 4a ), bis‐(3,4‐difluorophenyl)‐(4‐hydroxyphenyl)phosphine oxide ( 4b ), and 4‐hydroxyphenyl‐bis‐(3,4,5‐trifluorophenyl)phosphine oxide ( 4c ) were prepared, characterized, and polymerized under nucleophilic aromatic substitution conditions [N‐methylpyrrolidone (NMP), K2CO3] to provide the corresponding hyperbranched poly(arylene ether phosphine oxide)s with number‐average molecular weights ranging from 9200 to 14,600 Da. NMR spectroscopic analysis indicated the presence of highly branched products with an approximate degree of branching of 0.57. The polymers were soluble in a variety of typical organic solvents and displayed excellent thermal stability. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1456–1467, 2002  相似文献   

6.
Proton transfer polymerization through thiol‐epoxy “click” reaction between commercially available and hydrophilic di‐thiol and di‐epoxide monomers is carried out under ambient conditions to furnish water‐soluble polymers. The hydrophilicity of monomers permitted use of aqueous tetrahydrofuran as the reaction medium. A high polarity of this solvent system in turn allowed for using a mild catalyst such as triethylamine for a successful polymerization process. The overall simplicity of the system translated into a simple mixing of monomers and isolation of the reactive polymers in an effortless manner and on any scale required. The structure of the resulting polymers and the extent of di‐sulfide defects are studied with the help of 13C‐ and 1H‐NMR spectroscopy. Finally, reactivity of the synthesized polymers is examined through post‐polymerization modification reaction at the backbone sulfur atoms through oxidation reaction. The practicality, modularity, further functionalizability, and water solubility aspects of the described family of new poly(β‐hydroxythio‐ether)s is anticipated to accelerate investigations into their potential utility in bio‐relevant applications. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 3381–3386  相似文献   

7.
Fluorine‐containing poly(aryl ether 1,3,4‐ozadiazole)s were synthesized by the nucleophilic aromatic substitution reaction of 2,5‐bis(2,3,4,5,6‐pentafluorophenyl)‐1,3,4‐oxadiazole and various bisphenols in the presence of potassium carbonate. The polymerizations were carried out at 30 °C in 1‐methyl‐2‐pyrrolidinone to avoid the gelation caused by a crosslinking reaction at para and ortho carbons to the 1,3,4‐oxidiazole ring. The obtained polymers were all para‐connected linear structures. The obtained fluorine‐containing poly(aryl ether 1,3,4‐ozadiazole)s showed excellent solubility and afforded tough, transparent films by the solution‐casting method. They also exhibited a high glass transition temperature depending on the molecular structure, and the glass transition temperature could be controlled by the bisphenols in the range of 157–257 °C. They showed good thermal stability and excellent hydrophobicity due to the incorporation of the 2,3,5,6‐tetrafluoro‐1,4‐phenylene moiety. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2855–2866, 2007  相似文献   

8.
A series of poly(2‐methoxyethyl vinyl ether)s with narrow molecular weight distributions and with perfectly defined end groups of varying hydrophobicities was successfully synthesized by base‐assisting living cationic polymerization. The end group was shown to greatly affect the temperature‐induced phase separation behavior of aqueous solutions (lower critical solution temperature‐type phase separation) or organic solutions (upper critical solution temperature‐type phase separation) of the polymers. The cloud points were also influenced largely by the molecular weight and concentration of the polymer. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

9.
The effects of hydrophobic chain end groups on the cloud points of thermo‐sensitive water‐soluble polystyrenics were investigated. Well‐defined poly (4‐vinylbenzyl methoxytris(oxyethylene) ether) (PTEGSt) and poly(α‐hydro‐ω‐(4‐vinylbenzyl)tetrakis(oxyethylene)) (PHTrEGSt) were prepared by nitroxide‐mediated radical polymerization using α‐hydrido alkoxyamine initiators including two monomer‐based initiators. The polymers were reduced with (n‐Bu)3SnH to replace the alkoxyamine end group with hydrogen. In the studied molecular weight range (Mn,GPC = 3000 to 28,000 g/mol), we found that the hydrophobic end groups decreased the cloud point by 1–20 °C depending on the molecular weight and the largest depression was observed at the lowest molar mass. The cloud points of PTEGSt and PHTrEGSt with two hydrophobic end groups, phenylethyl and alkoxyamine, exhibited a monotonic increase with the increase of molecular weight. For polymers with only one hydrophobic end group, either phenylethyl or alkoxyamine, the cloud point initially increased with the increase of molecular weight but leveled off/decreased slightly with further increasing molar mass. For polymers with essentially no end groups, the cloud point decreased with the increase of chain length, which represents the “true” molecular weight dependence of the cloud point. The observed molecular weight dependences of the cloud points of polystyrenics with hydrophobic end group(s) are believed to result from the combined end group effect and “true” molecular weight effect. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3707–3721, 2007  相似文献   

10.
The functionalization of anionically polymerized isoprene with cysteamine applying the thiol‐ene reaction is reported. Antimicrobial activity is implemented by quaternization of the amino functionality by either alkylation or by protonation. The resulting polymers were tested against Gram‐positive as well as Gram‐negative bacteria strains according to the Japanese Industrial Standard Z2801:2000 protocol, partly revealing excellent biocidal performance. Thermal stability up to 200°C allows extrusion processing of the functionalized poly(isoprene)s. The best performing polymer, that is, bearing butylated ammonium‐groups, was compounded with the commodity material poly(propylene). The compound bearing 5 wt % of the biocidal polymer exhibited satisfactory biocidal properties. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

11.
Hydrosilylation polymerizations of 1,1‐dimethyl‐2,5‐bis(4‐ethynylphenyl)‐3,4‐diphenylsilole with aromatic silylhydrides including 1,4‐bis(dimethylsilyl)benzene, 4,4′‐bis(dimethylsilyl)biphenyl, 2,5‐bis(dimethylsilyl)thiophene, and 2,7‐bis(dimethylsilyl)‐9,9‐dihexylfluorene in the presence of Rh(PPh3)3Cl catalyst in refluxed tetrahydrofuran afford a series of silole‐containing poly(silylenevinylene)s. Under optimum condition, the alkyne polyhydrosilylation reactions progress efficiently and regioselectively, yielding polymers with high molecular weights (Mw up to 95,300) and good stereoregularity (E content close to 99%) in high yields (up to 92%). The polymers are processable and thermally stable, with high decomposition temperatures in the range of 420?449 °C corresponding to 5% weight loss. They are weakly fluorescent in the solution state but become emissive in the aggregate and film states, demonstrating their aggregation‐enhanced emission characteristics. The explosive sensing capabilities of the polymers are examined in both solution and aggregate states. The emissions of the polymers aggregates in aqueous mixture are quenched more efficiently by picric acid in an exponential pattern with high quenching constants (up to 27,949 L mol?1), suggesting that the polymers aggregates are sensitive chemosensors for explosive detection. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

12.
A series of functionalized 2‐bromoisobutyrates and 2‐chloro‐2‐phenylacetates led to α‐end‐functionalized poly(methyl methacrylate)s in Ru(II)‐catalyzed living radical polymerization; the terminal functions included amine, hydroxyl, and amide. These initiators were effective in the presence of additives such as Al(Oi‐Pr)3 and n‐Bu3N. The chlorophenylacetate initiators especially coupled with the amine additive gave polymers with well‐controlled molecular weights (Mw/Mn = 1.2–1.3) and high end functionality (Fn ~ 1.0). © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1937–1944, 2002  相似文献   

13.
Low‐molecular‐weight poly(acrylic acid) (PAA) was synthesized by reversible addition fragmentation chain transfer polymerization with a trithiocarbonate as chain‐transfer agent (CTA). With a combination of NMR spectroscopy and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry, the PAA end‐groups of the polymer were analyzed before and after neutralization by sodium hydroxide. The polymer prior to neutralization is made up of the expected trithiocarbonate chain‐ends and of the H‐terminated chains issued from a reaction of transfer to solvent. After neutralization, the trithiocarbonates are transformed into thiols, disulfides, thiolactones, and additional H‐terminated chains. By quantifying the different end‐groups, it was possible to demonstrate that fragmentation is the rate limiting step in the transfer reaction. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5439–5462, 2004  相似文献   

14.
A π‐conjugated poly(dithiafulvene) ( 2 ) was obtained by the cycloaddition polymerization of aldothioketene with its alkynethiol tautomer derived from 1,4‐bis(1,2,3‐thiadiazolyl‐4‐yl)benzene ( 1 ) in a 94% yield. To a mixure of 1 and dimethyl sulfoxide (DMSO)/ethanol (5/1, v/v), KOH was added. After stirring the mixture overnight, piperidine was added to quench the terminal thioketenes. The reaction mixture was then poured into water to obtain the product. The cycloaddition polymerization of aldothioketene derived from 1 with its alkynethiol tautomer was studied under various conditions in several solvent systems. The structure of the polymer was supported by the 1H NMR and 13C NMR spectra. The number‐average degree of polymerization (DP) of 2 was 8, estimated from the 1H NMR analysis. Optical properties and electrochemical analysis of 2 were also studied. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5872–5876, 2004  相似文献   

15.
Reactivity of isothiocynate moieties in the side chain of polymethacrylate with amine, alcohol, or thiol was investigated, and the reactions were applied to preparation of networked polymers. Isothiocyanate of polymer side chain rapidly reacted with amines without a catalyst, to give the corresponding thioureas. However, it did not react with alcohols or thiols under the same conditions. Using 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) as a catalyst, addition of alcohols or thiols to the isothiocyanate proceeded smoothly. Addition of amines, alcohols, and thiols to isothiocyanates moiety contained in the side chain of polymethacrylate also proceeded readily with or without the catalyst, respectively, to effectively give the corresponding side chain modified polymers. Occurrence of these additions was confirmed by 1H NMR and IR measurements. Glass transition temperatures and thermal decomposition temperatures of the obtained polymers were investigated by differential scanning calorimetry and thermogravimetric analysis. Networked polymers were easily prepared by addition of 1,6‐hexamethylenediamine or hexamethylene glycol to the polymethacrylate having isothiocyanato groups. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1832–1842  相似文献   

16.
Low concentrations of 4‐vinylphenylboronic acid (VPBA) were copolymerized with 2‐N‐morpholinoethyl methacrylate (MEMA) by nitroxide mediated polymerization using BlocBuilder? unimolecular initiator at 80 to 90 °C. The MEMA/VPBA copolymerizations were performed at initial feed compositions (fVPBA,0) of 0.05 to 0.10 VPBA, with fVPBA,0 = 0.10 using dimethylacetamide (DMAc) solvent being most effective, as seen by a linear increase in number average molecular weight, Mn, versus conversion and low dispersity, ? < 1.40. The copolymers were further chain‐extended with a second batch of VPBA, resulting in a block copolymer with monomodal molecular weight distribution and ? = 1.66. For MEMA/VPBA copolymers, increases in VPBA composition and polymer solution concentration resulted in decreases in the cloud point temperature (CPT, typically varied between 27.4–37.8 °C) and CPT increased from 31.2 to 33.8 °C to about 88 °C with decreases in pH from 7 to 4. Rheological tests with small angle light scattering (SALS) confirmed CPTs measured by UV‐Vis and DLS. These copolymers were targeted as models to combine possible glucose‐sensing boronic acid functionality the thermoresponsiveness provided by MEMA groups. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1560–1572  相似文献   

17.
Various densely grafted polymers containing poly(aniline‐2‐sulfonic acid‐co‐aniline)s as side chains and polystyrene as the backbone were prepared. A styryl‐substituted aniline macromonomer, 4‐(4‐vinylbenzoxyl)(Ntert‐butoxycarbonyl)phenylamine (4‐VBPA‐tBOC), was first prepared by the reaction of 4‐aminophenol with the amino‐protecting moiety di‐tert‐butoxyldicarbonate, and this was followed by substitution with 4‐vinylbenzyl chloride. 4‐VBPA‐tBOC thus obtained was homopolymerized with azobisisobutyronitrile as an initiator, and this was followed by deprotection with trifluoroacetic acid to generate poly[4‐(4‐vinylbenzoxyl)phenylamine] (PVBPA) with pendent amine moieties. Second, the copolymerization of aniline‐2‐sulfonic acid and aniline was carried out in the presence of PVBPA to generate densely grafted poly(aniline‐2‐sulfonic acid‐co‐aniline). Through the variation of the molar feed ratio of aniline‐2‐sulfonic acid to aniline, various densely grafted copolymers were generated with different aniline‐2‐sulfonic acid/aniline composition ratios along the side chains. The copolymers prepared with molar feed ratios greater than 1/2 were water‐soluble and had conductivities comparable to those of the linear copolymers. Furthermore, these copolymers could self‐dope in water through intermolecular or intramolecular interactions between the sulfonic acid moieties and imine nitrogens, and this generated large aggregates. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1090–1099, 2005  相似文献   

18.
The synthesis of seven new aromatic diisocyanide monomers is described and a rationale for their stability is given, as well as their behavior in the palladium‐mediated aromatizing polymerization yielding helically chiral poly(quinoxalin‐2,3‐diyl)s (PQs). Acceleration of the otherwise slow polymerization by microwave heating was observed. The polymers are designed to display potential organocatalytically active functionalities (e.g., phenols, pyridines) nearby stereolabile biaryl axes, which are asymmetrically governed by the configurationally stable helical backbone. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4830–4839, 2009  相似文献   

19.
Two novel poly(amine‐hydrazide)s were prepared from the polycondensation reactions of the dicarboxylic acid, 9‐[N,N‐di(4‐carboxyphenyl)amino]anthracene ( 1 ), with terephthalic dihydrazide ( TPH ) and isophthalic dihydrazide ( IPH ) via the Yamazaki phosphorylation reaction, respectively. The poly(amine‐hydrazide)s were readily soluble in many common organic solvents and could be solution cast into transparent films. Differential scanning calorimetry (DSC) indicated that these hydrazide polymers had glass‐transition temperatures (Tg) in the range of 182–230 °C and could be thermally cyclodehydrated into the corresponding oxadiazole polymers in the range of 300–400 °C. The resulting poly(amine‐1,3,4‐oxadiazole)s had useful levels of thermal stability associated with high Tg (263–318 °C), 10% weight‐loss temperatures in excess of 500 °C, and char yield at 800 °C in nitrogen higher than 55%. These organo‐soluble anthrylamine‐based poly(amine‐hydrazide)s and poly (amine‐1,3,4‐oxadiazole)s exhibited maximum UV‐vis absorption at 346–349 and 379–388 nm in N‐methyl‐2‐pyrrolidone (NMP) solution, respectively. Their photoluminescence spectra in NMP solution showed maximum bands around 490–497 nm in the green region. The poly(amine‐hydrazide) I ‐ IPH showed a green photoluminescence at 490 nm with PL quantum yield of 29.9% and 17.0% in NMP solution and film state, respectively. The anthrylamine‐based poly(amine‐1,3,4‐oxadiazole)s revealed a electrochromic characteristics with changing color from the pale yellow neutral form to the red reduced form when scanning potentials negatively from 0.00 to ?2.20 V. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1584–1594, 2009  相似文献   

20.
We report the synthesis and thermosensitive properties of well‐defined water‐soluble polyacrylates and polystyrenics with short pendant oligo(ethylene glycol) groups. Four monomers, methoxydi(ethylene glycol) acrylate (DEGMA), methoxytri(ethylene glycol) acrylate (TEGMA), α‐hydro‐ω‐(4‐vinylbenzyl)tris(oxyethylene) (HTEGSt), and α‐hydro‐ω‐(4‐vinylbenzyl)tetrakis(oxyethylene) (HTrEGSt), were prepared and polymerized by nitroxide‐mediated radical polymerization with 2,2,5‐trimethyl‐3‐(1‐phenylethoxy)‐4‐phenyl‐3‐azahexane as an initiator. Kinetics and gel permeation chromatography analysis showed that the polymerizations were controlled processes yielding polymers with controlled molecular weights and narrow polydispersities. All polymers could be dissolved in water, forming transparent solutions, and undergo phase transitions when the temperature was above a critical point. The thermosensitive properties were studied by turbidimetry and variable‐temperature 1H NMR spectroscopy. The cloud points of the polymers of DEGMA, TEGMA, HTEGSt, and HTrEGSt were around 38, 58, 13, and 64 °C, respectively. For all four polymers, the cloud point increased with decreasing concentration and increasing molecular weight in the studied molecular weight range of 5000–30,000 g/mol. The removal of the nitroxide group from the polymer chain end resulted in a higher cloud point. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2454–2467, 2006  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号