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1.
A series of four phosphonated‐bearing allyl monomers, that is, diethyl‐1‐allylphosphonate ( AP ), dimethyl‐1‐allyloxymethylphosphonate ( AOP ), 5‐ethyl‐5‐(allyloxymethyl)‐2‐oxo‐1,3,2‐dioxaphosphorinane ( AEDPH ), and 2‐benzyl‐5‐ethyl‐5‐(allyloxymethyl)‐2‐oxo‐1,3,2‐dioxaphosphorinane ( AEDPBn ) were synthesized. These monomers were then copolymerized by free radical polymerization in the presence of maleic anhydride, thus leading to alternated copolymers with phosphonate moieties. It was shown that both monomer conversion and reaction rate were dependent on the phosphonate moieties carried out by the allyl monomer: the bulkier the phosphonate group, the higher the polymerization rate. Thermogravimetric analysis of the copolymers revealed a high content of residue, also varying with the nature of the phosphonate moieties. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   

2.
A series of α,ω‐heterodifunctional monomers with styrene (St) and maleimide moieties bridged by a varied length of oligo‐ethylene glycol (OEG) linkers were synthesized. Cyclopolymerizations of these monomers through reversible addition–fragmentation chain transfer‐mediated alternating radical copolymerization between intramolecular St and maleimide moieties were investigated. For the monomers with three or more ethylene glycol (EG) units, their cyclopolymerizations can be realized properly in low monomer feeding concentrations, affording well‐defined cyclopolymers with crown ether encircled in their main chains. Importantly, the cyclopolymerizations of monomers with six or seven EG units in the presence of KPF6 could be enhanced by the supramolecular effects between the OEG linkers and the potassium metal ion. Thus, the monomer feeding concentration could be largely improved, which may benefit preparation of the cyclopolymers with high degrees of copolymerization. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 330–338  相似文献   

3.
Solution and dispersion copolymerizations of N‐phenylmaleimide (PMI) with either styrenics or alkyl vinyl ethers (AVEs), systems with a tendency to give alternating polymers, were investigated with the goal of producing high glass transition particles. Equimolar solution copolymerization of PMI with styrenics gave alternating copolymers, whereas AVEs gave PMI‐rich copolymers (~65:35) except for t‐butyl vinyl ether, which gave copolymers with only a slight excess of PMI. These copolymers had glass transition temperatures (Tgs) ranging from 115 to 225 °C depending on comonomer(s). Dispersion copolymerization in ethanol‐based solvents in the presence of poly(vinylpyrrolidone) as steric stabilizer led to narrow‐disperse microspheres for many copolymers studied. Dispersion copolymeriations of PMI with styrenics required good cosolvents such as acetonitrile or methyl ethyl ketone as plasticizers during particle initiation and growth. Dispersion copolymerizations generally resulted in copolymer particles with compositions and Tgs very similar to those of the corresponding copolymers formed by solution polymerization, with the exception of t‐butyl vinyl ether (tBVE), which now behaved like the other AVEs. Dispersion terpolymerizations of PMI (50 mol %) with different ratios of either n‐butylstyrene and t‐butylstyrene or n‐butyl vinyl ether and tBVE led to polymer particles with Tgs that depended on the ratio of the two butyl monomers. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010  相似文献   

4.
Radical copolymerizations of electron‐deficient 2‐trifluoromethylacrylic (TFMA) monomers, such as 2‐trifluoromethylacrylic acid and t‐butyl 2‐trifluoromethylacrylate (TBTFMA), with electron‐rich norbornene derivatives and vinyl ethers with 2,2′‐azobisisobutyronitrile as the initiator were investigated in detail through the analysis of the kinetics in situ with 1H NMR and through the determination of the monomer reactivity ratios. The norbornene derivatives used in this study included bicyclo[2.2.1]hept‐2‐ene (norbornene) and 5‐(2‐trifluoromethyl‐1,1,1‐trifluoro‐2‐hydroxylpropyl)‐2‐norbornene. The vinyl ether monomers were ethyl vinyl ether, t‐butyl vinyl ether, and 3,4‐dihydro‐2‐H‐pyran. Vinylene carbonate was found to copolymerize with TBTFMA. Although none of the monomers underwent radical homopolymerization under normal conditions, they copolymerized readily, producing a copolymer containing 60–70 mol % TFMA. The copolymerization of the TFMA monomer with norbornenes and vinyl ethers deviated from the terminal model and could be described by the penultimate model. The copolymers of TFMA reported in this article were evaluated as chemical amplification resist polymers for the emerging field of 157‐nm lithography. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1478–1505, 2004  相似文献   

5.
A vinyl ether bearing a carbonate side group (2‐oxo‐1,3‐dioxolan‐4‐yl‐methyl vinyl ether, GCVE) was synthesized and copolymerized with various commercially available fluoroolefins [chlorotrifluoroethylene (CTFE), hexafluoropropylene (HFP), and perfluoromethyl vinyl ether (PMVE)] by radical copolymerization initiated by tert‐butyl peroxypivalate. Although HFP, PMVE, and vinyl ether do not homopolymerize under radical conditions, they copolymerized easily yielding alternating poly(GCVE‐alt‐F‐alkene) copolymers. These alternating structures were confirmed by elemental analysis as well as 1H, 19F, and 13C NMR spectroscopy. All copolymers were obtained in good yield (73–85%), with molecular weights ranging from 3900 to 4600 g mol?1 and polydispersities below 2.0. Their thermogravimetric analyses under air showed decomposition temperatures at 10% weight loss (Td,10%) in the 284–330°C range. The HFP‐based copolymer exhibited a better thermal stability than those based on CTFE and PMVE. The glass transition temperatures were in the 15–65°C range. These original copolymers may find potential interest as polymer electrolytes in lithium ions batteries. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

6.
Novel copolymers composed of a styrene (St) derivative bearing a vicinal tricarbonyl moiety and various vinyl monomers such as St, methyl methacrylate (MMA), and N‐vinylpyrrolidone (NVP) were synthesized by (1) radical copolymerization of a St derivative with a 1,3‐diketone structure with St, MMA, and NVP and (2) successive oxidation of the resulting copolymers with N‐bromosuccinimide in DMSO to convert their 1,3‐diketone moieties in the side chains into the corresponding vicinal tricarbonyl moieties. Their tricarbonyl moieties were readily hydrated in water‐containing acetone to generate the corresponding copolymers bearing geminal diol structures in the side chains. On the other hand, heating the resulting copolymers bearing the geminal diol structures in vacuo‐enabled successful recovery of the vicinal tricarbonyl moieties to demonstrate the reversible nature of this system. The hydration behavior in powdery state under air atmosphere saturated by water was also investigated. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

7.
The process of formation of reticular copolymer molecular structures produced in free radical copolymerization of divinyl monomers (divinyl ethers of diethylene glycol and hydroquinone, divinyl sulfide, p-divinylbenzene, etc.) with maleic and fumaric acid derivatives is studied. The basic factor that determines the features of molecular and network structures of copolymers is reactivity of the divinyl monomer in copolymerization with monovinyl monomer. The network of copolymers of maleic anhydride with the divinyl ether of hydroquinone is formed out of oligomer microgels. Divinyl sulfide in copolymerization with maleic acid is disposed to cyclocopolymerization; also crosslinking reactions occur. Formation of a network structure of copolymers of divinylbenzene with maleic and fumaric acid derivatives is shown to proceed via an alternating copolymerization mechanism. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36 : 371–378, 1998  相似文献   

8.
The synthesis and characterization of novel poly(CTFE‐g‐oligoEO) graft copolymers [chlorotrifluoroethylene (CTFE) and ethylene oxide (EO)] are presented. First, vinyl ether monomers bearing oligo(EO) were prepared by transetherification of ω‐hydroxyoligo(EO) with ethyl vinyl ether catalyzed by a palladium complex in 70–84% yields. Two vinyl ethers of different molecular weights (three and 10 EO units) were thus obtained. Then, radical copolymerization of the above vinyl ethers with CTFE led to alternating poly(CTFE‐alt‐VE) copolymers that bore oligo(OE) side chains in satisfactory yields (65%). These original poly(CTFE‐g‐oligoEO) graft copolymers were characterized by 1H, 19F, and 13C NMR spectroscopy. Their molecular weights reached 19,000 g mol?1, and their thermal properties were investigated while their glass transition temperatures ranged between ?42 and ?36 °C. Their thermogravimetric analyses under air showed decomposition temperatures of 270 °C with 10% weight loss (Td,10%). These novel copolymers are of potential interest as polymer electrolytes in lithium ion batteries, showing room temperature conductivities ranging from 4.49 × 10?7 to 1.45 × 10?6 S cm?1 for unplasticized material. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013  相似文献   

9.
Thermosensitive homopolymers and copolymers with hydroxy groups were synthesized via the living cationic polymerization of Si‐containing vinyl ethers. The cationic homopolymerization and copolymerization of five vinyl ethers with silyloxy groups, each with a different spacer length, were examined with a cationogen/Et1.5AlCl1.5 initiating system in the presence of an added base. When an appropriate base was added, the living cationic polymerization of Si‐containing monomers became feasible, giving polymers with narrow molecular weight distributions and various block copolymers. Subsequent desilylation gave well‐defined polyalcohols, in both water‐soluble and water‐insoluble forms. One of these polyalcohols, poly(4‐hydroxybutyl vinyl ether), underwent lower‐critical‐solution‐temperature‐type thermally induced phase separation in water at a critical temperature (TPS) of 42 °C. This phase separation was quite sensitive and reversible on heating and cooling. The phase separation also occurred sensitively with random copolymers of thermosensitive and hydrophilic or hydrophobic units, the TPS values of which in water could be controlled by the monomer feed ratio. The thermal responsiveness of this polyalcohol unit made it possible to prepare novel thermosensitive block and random copolymers consisting solely of alcohol units. One example prepared in this study was a 20 wt % aqueous solution of a diblock copolymer consisting of thermosensitive poly(4‐hydroxybutyl vinyl ether) and water‐soluble poly(2‐hydroxyethyl vinyl ether) segments, which transformed into a physical gel above 42 °C. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3300–3312, 2003  相似文献   

10.
This work deals with design of maleimide monomer toward more precise control of alternating sequence for radical copolymerization with styrene. Crucial in this study is sequence analysis by MALDI‐TOF‐MS for resultant copolymers that was obtained via ruthenium‐catalyzed living radical copolymerization with a malonate‐based alkyl halide initiator showing selective initiation ability. The copolymers of a simple N‐alkyl maleimide [e.g., N‐ethyl maleimide (EMI)] with styrene gave complicated peak patterns for the MALDI‐TOF‐MS spectra indicating low degree of alternating sequence, in contrary to expectation from the reactivity ratios (almost zero). A simple substitution of methyl group (CH3) of EMI with trifluoromethyl (CF3: CF3‐MI) made the peak patterns much simpler giving the copolymer with higher alternating sequence. More interestingly, the peak interval of the copolymer at earlier polymerization stage was equal to sum of the molecular weights of CF3‐MI and styrene, suggesting possibility of the pair propagation of the monomers. Indeed, 1H NMR analyses of the mixture of maleimide with styrene suggested stronger interaction of CF3‐MI than EMI. Based on the results, maleimide derivatives carrying a substituent‐designable electron‐withdrawing group [ROC(?O)N–: R = substituent] were newly designed toward incorporation of functional side chains. They also gave higher alternating sequence for the copolymerization with styrene. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 367–375  相似文献   

11.
The (controlled) free‐radical copolymerization of maleic anhydride and styrene or derivatives thereof is often thought to provide nearly perfect alternating copolymers. Here, the RAFT copolymerization of electron‐rich styrene derivatives with maleic anhydride is reported. This copolymerization shows distinct penultimate effects, resulting in polymers with increased incorporation of styrene monomers, that is, where a tendency toward periodic (S‐S‐MA) copolymers exists. This work could be a first step towards periodic copolymers based on maleic anhydride and styrene derivatives. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2932–2939  相似文献   

12.
The free-radical terpolymerization of maleic anhydride (MSA), isobutyl vinyl ether (VIBE) and anethol (ANE) at 60°C is described. These three monomers do not homopolymerize under the conditions used. Binary copolymers are only obtained from MSA and one of the two investigated donor monomers, whereas the binary copolymerization of VIBE with ANE is not possible. In all terpolymers from these three non-homopolymerizable monomers the MSA content amounts to about 50 mol-%; VIBE is about twice as reactive as ANE. The terpolymerization can formally also be described under the assumption that two binary complexes (MSA/ANE (I) and MSA/VIBE (II)) are copolymerized. For this case the reactivity ratios rI = 0,9 and rII = 1,7 are obtained.  相似文献   

13.
Stimuli‐responsive gradient copolymers, composed of various monomers, were synthesized by living cationic polymerization in the presence of base. The monomers included thermosensitive 2‐ethoxyethyl vinyl ether (EOVE) and 2‐methoxyethyl vinyl ether (MOVE), hydrophobic isobutyl vinyl ether (IBVE) and 2‐phenoxyethyl vinyl ether (PhOVE), crystalline octadecyl vinyl ether (ODVE), and hydrophilic 2‐hydroxyethyl vinyl ether (HOVE). The synthesis of gradient copolymers was conducted using a semibatch reaction method. Living cationic polymerization of the first monomer was initiated using a conventional syringe technique, followed by an immediate and continuous addition of a second monomer using a syringe pump at regulated feed rates. This simple method permitted precise control of the sequence distribution of gradient copolymers, even for a pair of monomers with very different relative monomer reactivities. The stimuli‐responsive gradient, block and random copolymers exhibited different self‐association behavior. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6444–6454, 2008  相似文献   

14.
Copolymerizations of 1,3-dehydroadamantane, 1, and various vinyl monomers were carried out in THF at room temperature. On mixing 1 with electron-deficient vinyl monomers, such as acrylonitrile and methyl acrylate, in the absence of any initiator, the copolymerization spontaneously proceeded to give alternating copolymers in 28-88% yield. By contrast, no reaction of 1 occurred at all when isobutyl vinyl ether or styrene was mixed under similar conditions. These contrastive results indicate the high electron density of a central sigma-bond in a strained [3.3.1]propellane derivative, 1. Alternating sequences of the resulting copolymers were characterized by NMR and MALDI-TOF-MS measurements. DSC and TGA measurements revealed the high thermal stability of the alternating copolymers containing bulky, stiff, and strain-free adamantane skeletons.  相似文献   

15.
A vinyloxy monomer having an electron‐accepting chromophore moiety, p‐((vinyloxy)methyl)benzonitrile (VOMBN), was synthesized by reaction of p‐(hydroxymethyl)benzonitrile with ethyl vinyl ether (EVE) in the presence of mercuric acetate. VOMBN can easily be cationically homopolymerized and copolymerized with EVE by using Lewis acids such as boron trifluoride etherate (BF3 · OEt2) as a catalyst and radically copolymerized with maleic anhydride (MAn) using AIBN as an initiator. The fluorescence behaviors of VOMBN, its copolymer P(VOMBN‐co‐MAn), and its saturated model compound p‐(ethoxymethyl)benzonitrile (EOMBN) were investigated in acetonitrile. It has been found that the fluorescence intensity of VOMBN is much lower than its copolymer and EOMBN at the same chromophore concentration. A fluorescence “structural self‐quenching effect” (SSQE) is also observed for VOMBN as we have reported previously [Li, F. M.; Chen, S. J.; Li, Z. C.; Qiu, J. J Polym Sci Polym Chem 1996, 34, 1881]. This phenomenon has been attributed to the inter‐ and intramolecular charge transfer interaction between the electron‐accepting cyanophenyl chromophore and the electron‐donating vinyloxy group in the same molecule. The dependence of the fluorescence intensity of VOMBN on solvents of different viscosities is evidence that the SSQE of VOMBN mainly occurs intramolecularly. The fluorescence of EOMBN and P(VOMBN‐co‐MAn) was quenched by a series of electron‐rich vinyloxy compounds which do not have chromophore moieties, such as dihydrofuran (2H‐furan), dihydropyran (2H‐pyran), furan, and EVE. It is observed that the higher the electron‐donating ability of the quenchers, the greater the quenching efficiency. P(VOMBN) and the random copolymers of VOMBN with EVE show broader fluorescence spectra as compared to the alternating copolymer P(VOMBN‐co‐MAn). This indicates that there is a mutual interaction between the adjacent cyanophenyl groups in P(VOMBN) and P(VOMBN‐co‐EVE), whereas such an interaction does not exist for P(VOMBN‐co‐MAn) in which the cyanophenyl groups are isolated by the rigid succinic anhydride rings. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 179–187, 1999  相似文献   

16.
Phosphorus‐containing vinyl ether monomers and 1‐propenyl ether monomers were prepared by the regioselective addition reaction of glycidyl vinyl ether (GVE) or 1‐propenyl glycidyl ether with diaryl phosphonates with quaternary onium salts as catalysts. The reaction of GVE with bis(4‐chlorophenyl) phenylphosphonate gave bis[1‐(4‐chlorophenoxy methyl)‐2‐(vinyloxy)ethyl]phenylphosphonate in a 68% yield. The structures of the resulting phosphorus‐containing vinyl ether monomers and 1‐propenyl ether monomers were confirmed by IR and 1H NMR spectra and elemental analysis. Photoinitiated cationic polymerizations of the resulting phosphorus‐containing vinyl ether monomers and 1‐propenyl ether monomers were investigated with photoacid generators. The polymerization of vinyl ether groups and 1‐propenyl ether groups of the obtained monomers proceeded very smoothly with a sulfonium‐type cationic photoinitiator, bis[4‐(diphenylsulfonio)phenyl]sulfide‐bis(hexafluorophosphate), upon UV irradiation. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3105–3115, 2005  相似文献   

17.
Two phosphorus‐containing acrylate monomers were synthesized from the reaction of ethyl α‐chloromethyl acrylate and t‐butyl α‐bromomethyl acrylate with triethyl phosphite. The selective hydrolysis of the ethyl ester monomer with trimethylsilyl bromide (TMSBr) gave a phosphonic acid monomer. The attempted bulk polymerizations of the monomers at 57–60 °C with 2,2′‐azobisisobutyronitrile (AIBN) were unsuccessful; however, the monomers were copolymerized with methyl methacrylate (MMA) in bulk at 60 °C with AIBN. The resulting copolymers produced chars on burning, showing potential as flame‐retardant materials. Additionally, α‐(chloromethyl)acryloyl chloride (CMAC) was reacted with diethyl (hydroxymethyl)phosphonate to obtain a new monomer with identical ester and ether moieties. This monomer was hydrolyzed with TMSBr, homopolymerized, and copolymerized with MMA. The thermal stabilities of the copolymers increased with increasing amounts of the phosphonate monomer in the copolymers. A new route to highly reactive phosphorus‐containing acrylate monomers was developed. A new derivative of CMAC with mixed ester and ether groups was synthesized by substitution, first with diethyl (hydroxymethyl)phosphonate and then with sodium acetate. This monomer showed the highest reactivity and gave a crosslinked polymer. The incorporation of an ester group increased the rate of polymerization. The relative reactivities of the synthesized monomers in photopolymerizations were determined and compared with those of the other phosphorous‐containing acrylate monomers. Changing the monomer structure allowed control of the polymerization reactivity so that new phosphorus‐containing polymers with desirable properties could be obtained. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2207–2217, 2003  相似文献   

18.
Novel trifunctional monomers based on renewable resources were prepared and subsequently polymerized via the Diels‐Alder (DA) polycondensation between furan and maleimide complementary moieties. Three basic approaches were considered for these nonlinear DA polycondensations, namely the use of (i) a bisfuran monomer in combination with a trismaleimide (A2 + B3 system) and (ii) a trisfuran monomer in conjunction with a bismaleimide (A3 + B2 system) leading to branched or crosslinked materials, and (iii) the use of monomers incorporating both furan and maleimide end groups (A2B or AB2 systems), which lead to hyperbranched structures. The application of the retro‐DA reaction to the ensuing polymers confirmed their thermoreversible character. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013  相似文献   

19.
Radical copolymerization of tetraethyl vinylidene phosphonate ( B ) with vinyl monomers has been described for the first time. In copolymerization with vinyl acetate ( V ) strictly alternating copolymer was formed even when [ V ]0/[ B ]0 was equal to 80. In copolymerization with acrylic acid ( A ) copolymers of the general structure ‐[( B )1 A x)]n‐ were formed. The number of A units (x) was shown to depend on the [ A ]0/[ B ]0 ratio in the monomers feed. The reactivity ratio rA was determined as equal to 2.1 and on this basis, the distribution of x as a function of [ A ]0/[ B ]0 was found. Bisphosphonic units were deblocked and the corresponding polyacids were analyzed by NMR spectra. Mn > 0.5 × 106 were measured by SEC for copolymers of B with A . © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

20.
Novel dental monomers containing both phosphonic and carboxylic acid functional groups were prepared. The monomers were based on t‐butyl α‐bromomethacrylate (t‐BuBMA) and synthesized in three steps: The reaction of o‐hydroxyaryl phosphonates [diethyl (2‐hydroxyphenyl) phosphonate, tetraethyl (2,5‐dihydroxy‐1,4‐phenylene) diphosphonate and tetraethyl 5,5′‐(propane‐2,2‐diyl)bis(2‐hydroxy‐5,1‐ phenylene) diphosphonate] with t‐BuBMA, the hydrolysis of phosphonate groups to phosphonic acid using trimethyl silylbromide, and the hydrolysis of the t‐butyl groups to carboxylic acid with trifluoroacetic acid. The monomers were solids and soluble in water and ethanol. The structures of the monomers were determined by Fourier transform infrared (FTIR), 1H, 13C, and 31P nuclear magnetic resonance (NMR) spectroscopy. The copolymerization behaviors of the synthesized monomers with glycerol dimethacrylate were first investigated in bulk using photodifferential scanning calorimetry at 40 °C with 2,2′‐dimethoxy‐2‐phenyl acetophenone as photoinitiator. Then, the solution copolymerization of the monomers with acrylamide in ethanol and water was studied, indicating that the synthesized monomers are incorporated into the copolymers. The acidic nature of the aqueous solutions of these monomers (pH values 1.72–1.87) is expected to give them etching properties important for dental applications. The interaction of the monomers with hydroxyapatite was investigated using 13C NMR and FTIR techniques. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1953–1965, 2009  相似文献   

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