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1.
A new type of maleimide monomer, N‐(4‐acetylphenyl)maleimide (NAPMI), was synthesized. The oxime, carbazone, and thiosemicarbazone derivatives of NAPMI were prepared with hydroxylamine hydrochloride, semicarbazide hydrochloride, and thiosemicarbazide hydrochloride, respectively. Radical homopolymerization of NAPMI and its derivatives were prepared at 60 °C in dimethyl sulfoxide solution with azobisisobutyronitrile as an initiator. The monomers and theirs homopolymers were characterized with Fourier transform infrared and NMR techniques. The glass‐transition temperatures, thermal stability, and ultraviolet stability of the polymers are compared. The activation energies of the thermal degradation of polymers were calculated by the Kissinger method. The antibacterial and antifungal effects of the monomers and polymers were also investigated on various bacteria and fungi. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1942–1951, 2003  相似文献   

2.
Copolymers of monomers 2,4‐dichlorophenyl methacrylate (2,4‐DMA) and methyl methacrylate (MMA) were synthesized with different monomer feed ratios using toluene as a solvent and 2,2′‐azobisisobutyronitrile (AIBN) as an initiator at 70 °C. The copolymers were characterized by IR‐spectroscopy, and copolymer composition was determined with UV‐spectroscopy. The linearization method of Fineman–Ross was employed to obtain the monomer reactivity ratios. The molecular weights and polydispersity indexes were determined by gel permeation chromatography (GPC). Thermogravimetric analyses of polymers were carried out in nitrogen atmosphere. The homo‐ and copolymers were tested for their antimicrobial properties against selected microorganisms. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5227–5234, 2004  相似文献   

3.
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   

4.
A new type of methacrylate monomer,2-(4-benzoylphenoxy)-2-oxoethyl methylacrylate(BOEMA) was synthesized.The radical homopolymerization of BOEMA was performed at 65℃in a 1,4-dioxane solution with benzoyl peroxide as an initiator.The oxime and thiosemicarbazone derivatives of poly[2-(4-benzoylphenoxy)-2-oxoethyl methylacrylate]poly(BOEMA) were prepared with hydroxylamine hydrochloride,and thiosemicarbazone hydrochloride, respectively.The monomer and its homopolymer were characterized with Fourier transform infrared and NMR techniques. The thermal stabilities of poly(BOEMA) and its derivatives were investigated with thermogravimetric analysis and differential scanning calorimetry.The ultraviolet stability of the polymers was compared.The antibacterial and antifungal effects of the monomer and the polymer and its derivatives were also investigated on various bacteria and fungi.The activation energies of the thermal degradation of the polymers were calculated with the Ozawa and Kissinger methods.  相似文献   

5.
Two new methacrylate monomers, 2‐[3‐(6‐tetralino)‐3‐methylcyclobutyl]‐2‐ketoethyl methacrylate (TKEMA) and 2‐(3‐mesityl‐3‐methylcyclobutyl)‐2‐ketoethyl methacrylate (MKEMA), were obtained from the reaction of 1‐chloroacetyl‐3‐methyl‐3‐arylcyclobutane with sodium methacrylate. The oxime and hydrazone derivatives of poly(TKEMA) and poly(MKEMA) were prepared with hydroxylamine and 2,4‐dinitrophenyl hydrazine. Poly(TKEMA) and poly(MKEMA), their oxime and hydrazone derivatives, and the monomers were characterized with Fourier transform infrared and NMR techniques. The glass‐transition temperatures and thermal stability of the polymers and their oxime and hydrazone derivatives were compared. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 4167–4173, 2001  相似文献   

6.
The reversible addition–fragmentation chain transfer (RAFT) polymerizations of 2‐naphthyl acrylate (2NA) initiated by 2,2′‐azobisisobutyronitrile were investigated with 2‐cyanoprop‐2‐yl 1‐dithionaphthalate (CPDN) as a RAFT agent at various temperatures in a benzene solution. The results of the polymerizations showed that 2NA could be polymerized in a controlled way by RAFT polymerization with CPDN as a RAFT agent; the polymerization rate was first‐order with respect to the monomer concentration, and the molecular weight increased linearly with the monomer conversion. The polydispersities of the polymer were relatively low up to high conversions in all cases. The chain‐extension reactions of poly(2‐naphthyl acrylate) (P2NA) with methyl methacrylate and styrene successfully yielded poly(2‐naphthyl acrylate)‐b‐poly(methyl methacrylate) and poly(2‐naphthyl acrylate)‐b‐polystyrene block polymers, respectively, with narrow polydispersities. The P2NA obtained by RAFT polymerization had a strong ultraviolet absorption at 270 nm, and the molecular weights had no apparent effect on the ultraviolet absorption intensities; however, the fluorescence intensity of P2NA increased as the molecular weight increased and was higher than that of 2NA. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2632–2642, 2005  相似文献   

7.
The microwave‐assisted statistical copolymerization of 2‐phenyl‐2‐oxazoline with 2‐methyl‐2‐oxazoline or 2‐ethyl‐2‐oxazoline is discussed in this contribution. Kinetic studies of these statistical copolymerizations as well as reactivity ratio determinations were performed to investigate the monomer distribution in these copoly(2‐oxazoline)s, demonstrating the formation of quasi‐diblock copolymers. In addition, the synthesis of copolymer series with monomer concentrations ranging from 0 to 100 mol % is described. These copolymer series were characterized with 1H NMR spectroscopy, gas chromatography, and gel permeation chromatography. Moreover, the glass‐transition temperatures and solubility of these copolymers were studied, and this revealing better mixing of poly(2‐methyl‐2‐oxazoline) (pMeOx) with poly(2‐phenyl‐2‐oxazoline) (pPhOx) than poly(2‐ethyl‐2‐oxazoline) (pEtOx) with poly(2‐phenyl‐2‐oxazoline) (pPhOx). © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 416–422, 2007.  相似文献   

8.
Well‐defined macromonomers of poly(ethylene oxide) and poly(tert‐butyl methacrylate) were obtained by anionic polymerization induced directly by the carbanion issued from 2‐methyl‐2‐oxazoline. When ethylene oxide was added to this carbanion with lithium as the counterion, a new compound able to initiate the polymerization of ε‐caprolactone in an anionically coordinated way was synthesized, and this led to well‐defined poly(ε‐caprolactone) macromonomers. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2440–2447, 2005  相似文献   

9.
A new graft copolymer, poly(2‐hydroxyethyl methacrylate‐co‐styrene) ‐graft‐poly(?‐caprolactone), was prepared by combination of reversible addition‐fragmentation chain transfer polymerization (RAFT) with coordination‐insertion ring‐opening polymerization (ROP). The copolymerization of styrene (St) and 2‐hydroxyethyl methacrylate (HEMA) was carried out at 60 °C in the presence of 2‐phenylprop‐2‐yl dithiobenzoate (PPDTB) using AIBN as initiator. The molecular weight of poly (2‐hydroxyethyl methacrylate‐co‐styrene) [poly(HEMA‐co‐St)] increased with the monomer conversion, and the molecular weight distribution was in the range of 1.09 ~ 1.39. The ring‐opening polymerization (ROP) of ?‐caprolactone was then initiated by the hydroxyl groups of the poly(HEMA‐co‐St) precursors in the presence of stannous octoate (Sn(Oct)2). GPC and 1H‐NMR data demonstrated the polymerization courses are under control, and nearly all hydroxyl groups took part in the initiation. The efficiency of grafting was very high. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5523–5529, 2004  相似文献   

10.
The polymerization of 9‐phenyl‐10,10‐dioxo‐thioxanthen‐9‐yl and 9‐phenyl‐10‐oxo‐9,10‐dihydroanthracen‐9‐yl methacrylates obtained under radical initiation (α,α‐azobisisobutyronitrile) in benzene solution proceeds with high isotactic specificity to afford homopolymers with a triad mm content higher than 95%, having presumably a helical main‐chain structure and showing significant resistance to solvolytic degradation in methanol. 9‐Phenyl‐10,10‐dipropyl‐9,10‐dihydroanthracen‐9‐yl methacrylate similarly affords isotactic polymers with an mm of 98% but is much less durable in contact with methanol. The high isotacticity observed for the aforementioned polymethacrylates as well as for poly(1‐phenyl‐dibenzosuberyl methacrylate), previously reported in the literature, reveal a tendency of ortho‐bridged triarylcarbinols to enforce isotacticity on their methacrylate polymers obtained under radical initiation. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 1180–1186, 2001  相似文献   

11.
The precipitation of Fe3O4 from an aqueous solution with ammonium hydroxide produced nanoparticles that were coated with a layer of oleic acid [or, in some cases, poly(ethylene oxide) or poly(vinylpyrrolidone)] before their dispersion into the organic phase. The encapsulation of magnetite nanoparticles in poly(2‐hydroxyethyl methacrylate) or poly(2‐hydroxyethyl methacrylate‐co‐glycidyl methacrylate) microparticles was achieved by dispersion polymerization in toluene/2‐methylpropan‐1‐ol. Magnetic poly(glycidyl methacrylate) microparticles were obtained in the presence of poly(ethylene oxide) at the magnetite/monomer interface. The particles containing up to 20 wt % iron maintained their discrete nature and did not aggregate. The effect of the reaction medium polarity, the concentrations of the monomer, initiator, and stabilizer, and the temperature on the particle size, particle size distribution, and iron and oxirane group contents was studied. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1848–1863, 2003  相似文献   

12.
A novel bis(ether anhydride) monomer, 2′,5′‐bis(3,4‐dicarboxyphenoxy)‐p‐terphenyl dianhydride, was synthesized from the nitro displacement of 4‐nitrophthalonitrile by the phenoxide ion of 2′,5′‐dihydroxy‐p‐terphenyl, followed by alkaline hydrolysis of the intermediate bis(ether dinitrile) and cyclodehydration of the resulting bis(ether diacid). A series of new poly(ether imide)s bearing laterally attached p‐terphenyl groups were prepared from the bis(ether anhydride) with various aromatic diamines via a conventional two‐stage process that included ring‐opening polyaddition to form the poly(amic acid)s followed by thermal or chemical imidization to the poly(ether imide)s. The inherent viscosities of the poly(amic acid) precursors were in the range of 0.62–1.26 dL/g. Most of the poly(ether imide)s obtained from both routes were soluble in polar organic solvents, such as N,N‐dimethylacetamide. All the poly(ether imide)s could afford transparent, flexible, and strong films with high tensile strengths. The glass‐transition temperatures of these poly(ether imide)s were recorded as between 214 and 276 °C by DSC. The softening temperatures of all the poly(ether imide) films stayed in the 207–265 °C range according to thermomechanical analysis. For all the polymers significant decomposition did not occur below 500 °C in nitrogen or air atmosphere. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1008–1017, 2004  相似文献   

13.
A set of new aromatic poly(ether amide)s containing benzimidazole groups and ethylene oxide sequences of different lengths were synthesized and characterized. The new polymers were prepared from two benzimidazole diamines, 2‐(4‐aminophenyl)‐5‐aminobenzimidazole and 2‐(3‐aminophenyl)‐5‐aminobenzimidazole, and various oligo(ethylene oxide)dibenzoyl chlorides. They exhibited good solubility in polar aprotic solvents and glass‐transition temperatures in the range of 125–300 °C (the longer the ethylene oxide spacer was, the lower the glass‐transition temperature was). The new polyamides were essentially amorphous, as observed by X‐ray diffraction measurements and confirmed by differential scanning calorimetry measurements, by means of which no melting endotherm was observed in any case. The decomposition temperatures, as revealed by thermogravimetric analysis in nitrogen, were about 400 °C for all of them, regardless of the length of the ethylene oxide content or the phenylene ring orientation (meta or para) of the diamine moiety. The number of ethylene oxide linkages per repeat unit also determined the water uptake. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1414–1423, 2006  相似文献   

14.
Two new initiators, namely, 4‐(4‐(2‐(4‐(allyloxy) phenyl)‐5‐hydroxypentane 2‐yl) phenoxy)benzaldehyde and 4‐(4‐(allyloxy) phenyl)‐4‐(4‐(4‐formylphenoxy) phenyl) pentyl 2‐bromo‐2‐methyl propanoate containing “clickable” hetero‐functionalities namely aldehyde and allyloxy were synthesized starting from commercially available 4,4′‐bis(4‐hydroxyphenyl) pentanoic acid. These initiators were utilized, respectively, for ring opening polymerization of ε‐caprolactone and atom transfer radical polymerization of methyl methacrylate. Well‐defined α‐aldehyde, α′‐allyloxy heterobifunctionalized poly(ε‐caprolactones) (Mn,GPC: 5900–29,000, PDI: 1.26–1.43) and poly(methyl methacrylate)s (Mn,GPC: 5300–28800, PDI: 1.19–1.25) were synthesized. The kinetic study of methyl methacrylate polymerization demonstrated controlled polymerization behavior. The presence of aldehyde and allyloxy functionality on polymers was confirmed by 1H NMR spectroscopy. Aldehyde‐aminooxy and thiol‐ene metal‐free double click strategy was used to demonstrate reactivity of functional groups on polymers. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013  相似文献   

15.
A new aromatic, tetrafunctional methacrylate monomer, 4,4′‐di(2‐hydroxy‐3‐methacryloyloxypropoxy)benzophenone, and its application to the synthesis of porous microspheres are presented. This new monomer was copolymerized with divinylbenzene in the presence of pore‐forming diluents. The properties of the obtained highly crosslinked microspheres were investigated as column packing for high‐performance liquid chromatography. Their porous structures in both dry and wet states were studied and compared with those of poly(divinylbenzene) and the less crosslinked copolymer of 2,3‐epoxypropyl methacrylate and divinylbenzene. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 7014–7026, 2006  相似文献   

16.
4‐Hydroxy‐2‐oxo‐2H‐1‐benzopyran‐3‐carboxaldehydes 2a‐d are prepared from 4‐hydroxy‐2‐oxo‐2H‐1‐benzopyrans 1a‐d via the Vielsmeyer Haack reaction. The 4‐hydroxy‐2‐oxo‐3‐(3′oxo‐3′‐phenylprop‐1′‐enyl)‐2H‐1‐benzopyrans 3a‐d are obtained from 2a‐d via the Claisen reaction. Refluxing compounds 3a‐d with hydrazine hydrate gave the 3‐phenyl‐5‐(4‐hydroxy‐2‐oxo‐2H‐1‐benzopyran‐3‐yl)‐1,4,5‐trihydropyra‐zols 4a‐d . Stirring compounds 2a‐d with semicarbazide hydrochloride in acidic medium gave the 4‐hydroxy‐2‐oxo‐2H‐1‐benzopyran‐3‐aldehyde‐semicarbazone 5a‐d , which on cyclisation with ferric chloride hexahydrate gave the 5‐(4‐hydroxy‐2‐oxo‐2H‐1‐benzopyran‐3‐yl)‐2,4‐dihydro[1,2,4]triazol‐3‐ones 6a‐d . All these compounds show significant antibacterial activities.  相似文献   

17.
Novel and well‐defined dendrimer‐star, block‐comb polymers were successfully achieved by the combination of living ring‐opening polymerization and atom transfer radical polymerization on the basis of a dendrimer polyester. Star‐shaped dendrimer poly(?‐caprolactone)s were synthesized by the bulk polymerization of ?‐caprolactone with a dendrimer initiator and tin 2‐ethylhexanoate as a catalyst. The molecular weights of the dendrimer poly(?‐caprolactone)s increased linearly with an increase in the monomer. The dendrimer poly(?‐caprolactone)s were converted into macroinitiators via esterification with 2‐bromopropionyl bromide. The star‐block copolymer dendrimer poly(?‐caprolactone)‐block‐poly(2‐hydroxyethyl methacrylate) was obtained by the atom transfer radical polymerization of 2‐hydroxyethyl methacrylate. The molecular weights of these copolymers were adjusted by the variation of the monomer conversion. Then, dendrimer‐star, block‐comb copolymers were prepared with poly(L ‐lactide) blocks grafted from poly(2‐hydroxyethyl methacrylate) blocks by the ring‐opening polymerization of L ‐lactide. The unique and well‐defined structure of these copolymers presented thermal properties that were different from those of linear poly(?‐caprolactone). © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6575–6586, 2006  相似文献   

18.
Optically active poly(m‐phenylene)s substituted with chiral oxazoline derivatives have been synthesized by the nickel‐catalyzed Yamamoto coupling reaction of optically active (S)‐4‐benzyl‐2‐(3,5‐dihalidephenyl)oxazoline derivatives (X = Br or I). The structures and chiroptical properties of the polymers were characterized by spectroscopic methods and thermal gravimetric analyses. The polymers showed higher absolute optical specific rotation values than their corresponding monomer, and showed a Cotton effect at transition region of conjugated main chain. The optical activities of the polymers should be attributed to the higher order structure such as helical conformations. Moreover, the helical conformation could be induced by addition of metal salts into polymer solutions. The polymers showed good thermal stabilities, which was attributable to the oxazoline side chains. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013  相似文献   

19.
2‐Methacryloyloxyethyl phosphorylcholine (MPC), a biomimetic monomer, was grafted from silicon wafer surfaces at room temperature by combining self‐assembly of initiator and surface‐initiated atom transfer radical polymerization. Two methods were used to control the grafting process. One was to add free initiator to the reaction system; the other was to add excess deactivator. The grafting densities up to 0.3 chains/nm2 were obtained. The surface thickness increased linearly with MPC conversion. The thickness depended on catalyst and monomer concentrations, as well as activator/deactivator ratio. Poly(MPC) layers of >100 nm thick were obtained by optimizing the polymerization conditions. A second block of either poly(MPC) or poly[2‐(dimethylamino)ethyl methacrylate] was also grown from the grafted poly(MPC), demonstrating the system livingness. X‐ray photoelectron spectroscopy was used to examine the surface chemical compositions showed good agreement with the theoretical values. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2931–2942, 2004  相似文献   

20.
Two types of arylidene compounds were synthesized by reacting p‐hydroxybenzaldehyde with acetone [1,5‐bis(4‐hydroxyphenyl)penta‐1,4‐dien‐3‐one] (PBHP) and cyclohexanone [2,6‐bis(4‐hydroxybenzylidene)cyclohexanone] (HBC). 1,4‐Pentadien‐3‐one‐1‐p‐hydroxyphenyl‐5‐p‐phenyl methacrylate (PHPPMA) and 4‐{[‐3‐(4‐hydroxybenzylidene)‐2‐oxocyclohexylidene]methyl}phenyl acrylate (HBA) were prepared by reacting PBHP and HBC with methacryloyl chloride and acryloyl chloride in the presence of triethylamine, respectively. Copolymerization of different feed compositions of PHPPMA and HBA with 2‐hydroxyethyl acrylate (HEA) was carried out using a free‐radical solution polymerization technique in ethyl methyl ketone (MEK) using benzoyl peroxide (BPO). All the monomer and polymers were characterized by IR and NMR (1H/13C) spectroscopic techniques. The reactivity ratio of the monomers were obtained using Fineman–Ross (FR), Kelen–Tudos (KT), and extended Kelen–Tudos (exKT) methods. The photocrosslinking properties of the polymers were done using a UV absorption spectroscopy technique. Homopolymers of both the arylidene polymers shows similar trend towards the rate of photocrosslinking. The rate of photocrosslinking was enhanced when the cyclohexanone based arylidene monomer was copolymerized with HEA. Thermal stability and molecular weights (Mw and Mn) of the polymers were determined. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3433–3444, 2004  相似文献   

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