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1.
Summary Kinetic analysis of the cationic polymerization of 5-methyl-2-oxazoline (5-MeOZO) was performed with methyl tosylate(MeOTs) and methyl iodide(MeI) initiators by using 1H NMR spectroscopy. With MeOTs the polymerization of 5-MeOZO proceeded through oxazolinium tosylate species 3 and 4 and the rate constant of propagation (kp) was determined. With MeI, on the other hand, the propagating ends are present in equilibrium between alkyl iodide (covalent) species 7, 9 and 11 and oxazolinium(ionic) species 6, 8 and 10. Two model reactions enabled to determine the equilibrium constant (K) of 6/7 and to evaluate the reactivity of covalent species 9 (reflected by kp(c)) and of ionic species 8 (reflected by kp(i)). Both species 8 and 9 propagate concurrently and contribute to the whole propagation at comparative extents. 相似文献
2.
Andrzej Dworak Rolf C. Schulz Ivan Panchev Barbara Trzebicka Rumiana Velitshkova 《Polymer International》1994,34(2):157-161
Poly(vinyl acetate-co-vinyl chloroformate) ( 1 ) was synthesized via phosgenation of poly(vinyl acetate-co-vinyl alcohol). It was shown that ( 1 ) is capable of initiating the polymerization of 2-phenyl-2-oxazoline and 2-methyl-2-oxazoline, when the counter ion is exchanged using potassium iodide. Polyvinyl acetate-graft-poly-2-phenyl-2-oxazoline and polyvinyl acetate-graft-poly-2-methyl-2-oxazoline are obtained in the grafting reaction. 相似文献
3.
Thanh-Xuan Lav Pierre Lemechko Estelle Renard Catherine Amiel Valérie Langlois Gisèle Volet 《Reactive and Functional Polymers》2013,73(8):1001-1008
A new monomer (2-(5-azidopentyl)-2-oxazoline) bearing an azido group was synthesized. The cationic ring-opening copolymerization of this monomer with 2-methyl-2-oxazoline resulted in a well-defined linear polymer backbone with pendant azido groups. Alkynyl-poly(d,l-lactide) was grafted onto the azido groups of poly(oxazoline) via a Huisgen 1,3-dipolar cycloaddition reaction to give a novel amphiphilic graft copolymer [poly(2-methyl-2-oxazoline-co-2-pentyl-2-oxazoline)-g-poly(d,l-lactide)] (P[(MeOx-co-PentOx)-g-LA]). Different graft copolymers were prepared with PLA of different lengths. Preliminary results of the self-association of this copolymer in water indicated the formation of nanoparticles, which suggests this copolymer may have applications as vehicles for drug delivery. 相似文献
4.
The miscibility of polysulfone (PSf) and poly(ether sulfone) (PES) with three tertiary amide polymers has been studied. PES
is miscible with poly(N-methyl-N-vinylacetamide) (PMVAc) and with poly(N,N-dimethylacrylamide) (PDMA) but not with poly(2-methyl-2-oxazoline) (PMOx). Miscible PES/PDMA blends show lower critical solution
temperature behavior. However, PSf is immiscible with all the three tertiary amide polymers. Previous studies have shown that
both PES and PSf are miscible with poly(N-vinyl-2-pyrrolidone). PES is also miscible with poly(2-ethyl-2-oxazoline) but PSf is not. Therefore, PES is more readily
miscible with tertiary amide polymers as compared to PSf.
Received: 23 October 1996/Revised: 11 November 1996/Accepted: 12 November 1996 相似文献
5.
Summary
Palladium clusters were synthesized by reduction of palladium(II) acetate in the presence of a bipyridyl ligand (1) with an initiator for polymerization of 2-methyl-2-oxazoline. The 1-protected palladium clusters were soluble in CHCl3 and CH2Cl2. The 1-protected palladium clusters were combined with 2-methyl-2-oxazoline in chloroform. After polymerization, the reacted bipyridyl
ligand was removed from the palladium cluster by suspending the obtained palladium clusters with pyridine. The 1H NMR measurement indicated that the reacted bipyridyl ligand was formed via surface polymerization of 2-methyl-2-oxazoline.
Received: 19 April 2001/Accepted: 2 May 2001 相似文献
6.
Summary
Miscibility of aliphatic polysulfoxides (1, 2) with other commodity polymers was examined by comparing glass transition temperature(s) (Tgs) of the mixture of these polymers with Tgs of the original polymers by differential scanning calorimetry. It was found that the aliphatic polysulfoxides had good miscibility
with poly(2-methyl-2-oxazoline) or/and poly(N-vinylpyrrolidone).
Received: 25 December 1997/Revised version: 23 February 1998/Accepted: 25 February 1998 相似文献
7.
Summary
Poly(phenyl vinyl sulfoxide) 1 was prepared by anionic polymerization and its properties as a polymer homolog of dimethyl sulfoxide (DMSO) were examined.
Polysulfoxide 1 was found to have good miscibility with poly(vinyl acetate) as well as poly(2-methyl-2-oxazoline) and poly(N-vinylpyrrolidone) by comparing glass transition temperature(s) (Tgs) of the mixture of these polymers with Tgs of the original polymers by differential scanning calorimetry.
Received: 4 March 1998/Accepted: 23 March 1998 相似文献
8.
Summary
A novel polymer homolog of N,N-dimethylacetamide (DMAc) having amide groups on all main chain carbons, poly(N,N-dimethylcarbamoylmethylene) 1, was prepared by heating poly(di-t-butyl fumarate) 2 at 180 °C for 2 hours followed by treatment with hexamethylphosphoramide at 180 °C for 5 hours. The structure of the obtained
polymer 1 was confirmed by 1H-, 13C-NMR and IR spectroscopy. The polymer 1 actually showed the properties based on its repeating structures. 1 had the amphiphilicity and was soluble both in protic and aprotic solvents. Furthermore, 1 showed the miscibility with commodity polymers such as poly(N-vinylpyrrolidone), poly(vinyl alcohol) and poly(vinyl chloride). In comparison with another polymer homolog of DMAc, poly(2-methyl-2-oxazoline),
the polymer 1 exhibited better miscibility with poly(N-vinylpyrrolidone).
Received: 24 June 1999/Accepted: 19 July 1999 相似文献
9.
HCl-doped poly(o-anisidine) (PANIS–HCl) and undoped poly(o-anisidine) (PANIS-base) were blended with poly(2-methyl-2-oxazoline) (PMOx) or poly(2-ethyl-2-oxazoline) (PEOx) by solution casting from dimethyl sulfoxide. Blends containing 50 wt % or less of PANIS–HCl or PANIS-base were flexible and homogeneous. The glass transition temperature of the blend continuously shifted away from that of PMOx or PEOx with increasing PANIS–HCl or PANIS-base content, indicating miscibility. The shift in the Tg value was larger for the PMOx blend than for the corresponding PEOx blend, suggesting a stronger interpolymer interaction in the former blend. Fourier transform infrared spectroscopic studies indicated the presence of specific interactions in the blends as evidenced by the changes of C=O and NH bands. Blends containing 50 wt % of PANIS–HCl showed conductivity of about 10-4 S/cm. © 1997 John Wiley & Sons, Inc. J Appl Polm Sci 65:391–397, 1997 相似文献
10.
Min Zhou Weinan Jiang Jiayang Xie Dr. Wenjing Zhang Zhemin Ji Jingcheng Zou Zihao Cong Ximian Xiao Jiawei Gu Prof. Runhui Liu 《ChemMedChem》2021,16(2):309-315
Poly(2-oxazoline)s have excellent biocompatibility and have been used as FDA-approved indirect food additives. The inert property of the hydrophilic poly(2-oxazoline)s suggests them as promising substitutes for poly(ethylene glycol) (PEG) in various applications such as anti-biofouling agents. It was recently reported that poly(2-oxazoline)s themselves have antimicrobial properties as synthetic mimics of host defense peptides. These studies revealed the bioactive properties of poly(2-oxazoline)s as a new class of functional peptide mimics, by mimicking host defense peptides to display potent and selective antimicrobial activities against methicillin-resistant Staphylococcus aureus both in vitro and in vivo, without concerns about antimicrobial resistance. The high structural diversity, facile synthesis, and potent and tunable antimicrobial properties underscore the great potential of poly(2-oxazoline)s as a class of novel antimicrobial agents in dealing with drug-resistant microbial infections and antimicrobial resistance. 相似文献
11.
Poly(2-methyl-2-oxazoline) (PMOx) was found to be miscible with poly (styrene-coallyl alcohol), poly(hydroxyether of bisphenol-A), poly (2-hydroxypropyl methacrylate) and poly(p-vinylphenol) (PVPh), when cast from N,N-dimethylformamide solutions and to form interpolymer complexes with PVPh in methanol solutions. The hydrogen bonding interactions between PMOx and hydroxyl-containing polymers were studied by infrared spectroscopy and compared with the corresponding blends of poly(2-ethyl-2-oxazoline) (PEOx). Except with phenoxy, PMOx interacts more strongly with hydroxyl-containing polymers than PEOx does. 相似文献
12.
Polyaniline (PANI) was doped with p-phenolsulfonic acid (PSA) or 5-sulfosalicylic acid (SSA). The PANI salts were blended with poly(N-vinyl-2-pyrrolidone), poly(N-methyl-N-vinylacetamide), poly(N,N-dimethylacrylamide), or poly(2-methyl-2-oxazoline) by solution casting from dimethyl sulfoxide. Blends containing up to 50% by weight of PANI salt were homogeneous and each exhibited a single glass transition temperature, indicating miscibility. Fourier transform infrared spectroscopic studies indicated that the carbonyl groups of the tertiary amide polymers interacted with the PANI salt as evidenced by the development of a shoulder at a lower frequency in the carbonyl stretching band. Electrical conductivities of the blends are in the range 10−5 to 10−3 S/cm, depending on the blend composition. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 1839–1844, 1998 相似文献
13.
Summary Poly(vinyl chloride-g-2-methyl-2-oxazoline) copolymers were prepared by grafting from the allyl chloride sites of PVC with KI or AgOSO3CF3 as coinitiators. Use of AgOSO3CF3 led to higher grafting efficiencies and higher contents of poly(2-methyl-2-oxazoline) in the graft copolymers. DTA analyses of the P(VC-g-Me-Oxz) identified the thermal transitions of this copolymer; TGA analyses showed that the graft copolymers were less thermally stable than the constituent homopolymers. Unlike blends of P(Me-Oxz) and PVC, the graft copolymers could be molded easily; the graft materials exhibited greater flexural moduli but lower HDT's than PVC. 相似文献
14.
Jarunee Jeerupan Tomoki Ogoshi Sachi Hiramitsu Kenji Umeda Tadamasa Nemoto Gen-ichi Konishi Tada-aki Yamagishi Yoshiaki Nakamoto 《Polymer Bulletin》2008,59(6):731-737
Summary Star-shaped poly(2-methyl-2-oxazoline) (POZO) was prepared by ring-opening polymerization of 2-methyl-2-oxazoline from a novel
calix[4]resorcinarene with reactive bromoethyl groups (8Br-CX4) as an initiator. The core-first method, which uses an active
multifunctional core to initiate growth of polymer chains, was applied for synthesis of star-shaped POZO based on 8Br-CX4.
The obtained star-shaped POZOs were characterized by 1H NMR, 13C NMR, FT-IR and DSC. From 1H NMR, DLS and fluorescence measurements, the star-shaped POZOs formed nanometer scale micelles in aqueous media composed
of hydrophobic calix[4]resorcinarene moieties and hydrophilic POZO groups. 相似文献
15.
Summary Linear and three-arm star tosyl-telechelic polyisobutylenes (i.e., PIB's carrying two and three p-toluene-sulfonic acid ester end groups, respectively) have been synthesized and characterized by a variety of techniques. Subsequently these prepolymers were used as macroinitiators for the ring opening polymerization of 2-methyl-2-oxazoline leading to linear poly(N-acetylethyleneimine-b-isobutylene-b-N-acetylethyleneimine) and three-arm star poly(N-acetylethyleneimine-b-isobutylene). High yields (78–98%) and blocking efficiencies (70–80%) have been obtained. The absence of free polyisobutylene in the product indicates highly efficient initiation of 2-methyl-2-oxazoline polymerization by the tosyl-telechelic polyisobutylene. The less than 100% blocking efficiencies are probably due to chain transfer to 2-methyl-2-oxazoline. Hydrolysis of these block copolymers yielded poly(ethyleneimine-b-isobutylenes).Present address: Department of Macromolecular Science, Case Western Reserve University, Cleveland, Ohio 44106.Present address: Central Research Institute for Chemistry, Hungarian Academy of Sciences, Budapest, Hungary. 相似文献
16.
Summary
Polymer hybrids were prepared by three kinds of octasilsesquioxanes having hydroxyl groups and organic polymers such as poly(2-methyl-2-oxazoline)
(POZO), poly(N-vinylpyrrolidone) (PVP), and poly(N,N-dimethylacrylamide) (PDMAAm) using hydrogen bonding interaction. The obtained homogeneous and transparent hybrid films could
be dissolved in solvents and cast again without any separation. It was found that the high homogeneity of polymer hybrids
was the result of hydrogen bonding interaction between octasilsesquioxanes and organic polymers from the carbonyl stretching
shifts in IR measurement. Also, the influence of flexibility of eight arms bound to silica-like core on the homogeneity of
polymer hybrids was examined.
Received: 8 May 2001/Accepted: 24 May 2001 相似文献
17.
Summary 2-methyl-2-oxazoline was polymerized by using poly(ethyleneglycoladipate) having tosylate end groups as an initiator. Polymerization was carried in bulk, and ABA type block copolymers were obtained containing poly(N-acetylethylenimine) as A block (hard part) and poly(ethyleneglycoladlpate) as B block (soft part). 相似文献
18.
Reaction of methyltrans-2,3-epoxyhexadecanoate (I) with benzonitrile in presence of boron trifluoride-etherate (BF3-etherate) as catalyst has yieldedcis-2-phenyl-4-tridecyl-5-carbomethoxy-2-oxazoline (II), methyl 2-hydroxy-3-benzamidohexadecanoate (IV) and methyl 2,3-dihydroxyhexadecanoate
(III). On the other hand, reactions of I with acetonitrile and acrylonitrile have resulted in the formation of their corresponding
hydroxyamides, methyl 2-hydroxy-3-acetamidohexadecanoate (VI) and methyl 2-hydroxy-3-acryloamido hexadecanoate (VII), respectively,
along with the product (III) only. Pyrolysis of hydroxyamides (IV), (VI) and (VII) afforded their corresponding 2-oxazolines,cis-2-phenyl-4-tridecyl-5-carboxy-2-oxazoline (V),cis-2-methyl-4-tridecyl-5-carboxy-2-oxazoline (VIII) andcis-2-vinyl-4-tridecyl-5-carboxy-2-oxazoline (IX), respectively, in good yields. The products have been characterized with the
help of spectral and microanalyses.
Presented at the 4th Annual Convention of the Indian Council of Chemists held in December 1984 at Gorakhpur University, India. 相似文献
19.
Summary The thermal stabilities of poly(-methylhydrogenitaconate-co-2-methyl-2-oxazoline) and poly(-methylhydrogenitaconate-co-2-ethyl-2-oxazoline) obtained by spontaneous copolymerization have been studied by programmed thermogravimetric analysis over the temperature range from 293 K to 773 K under a flow of nitrogen. Most of the copolymers do not show weight loss until 473 K and they degrade in one step. The kinetic parameters Ea, n and A were obtained following one method of thermogravimetric analysis. The reaction order for all copolymers was 1.0. The poly(-methylhydrogenitaconate-co-2-methyl-2-oxazoline)s were the most thermostable copolymers. 相似文献
20.
Yoshiki Chujo Kazuki Sada Takeshi Kawasaki Eiji Ihara Takeo Saegusa 《Polymer Bulletin》1993,31(3):311-316
Summary Telechelic bifunctional polyoxazoline (poly(N-acetylethylenimine), PAEI) was prepared by ring-opening polymerization of 2-methyl-2-oxazoline (1) in the presence ofp-(,-dibromo)xylene (2) as an initiator. The terminal propagating ends of this polyoxazoline were reacted with 3-aminopropyltrimethoxysilane (4) to give telechelic trimethoxysilyl-terminated polyoxazoline (5). Gelation of this telechelic polymer was carried out by hydrolysis and condensation of alkoxysilyl groups. By this method, the PAEI gels were obtained in good yields, and their degrees of swelling in the solvent could be controlled successfully by the feed ratios of the initiator to the monomer in the stage of the polymerization of 2-methyl-2-oxazoline. However, the cross-linked products were not stable and gradually dissolved in water. The gels were also swollen inN,N-dimethyl-formamide (DMF). The degrees of swelling of these gels were thus measured in DMF. 相似文献