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1.
Copolymers of allyl glycidyl ether (AGE) with acrylonitrile (AN) have been prepared by bulk polymerization of their monomers with gamma rays. Copolymers thus obtained were characterized by Fourier transform infrared (FTIR), and ultraviolet (UV) spectroscopic techniques. The composition of the copolymers is determined indirectly by FTIR, UV, and directly by elemental analysis. The results obtained by different methods are compared. The reactivity ratios of monomer pairs (AGE + AN) which copolymerized heterogeneously were calculated by using different methods of determination. Among the three experimental methods used for the analysis of compositions and two theoretical methods of computations, the elemental analysis technique and the application of nonlinear least-squares method gave the most reliable reactivity ratios. These are found to be 1.86 and 0.21 for acrylonitrile and allyl glycidyl ether, respectively. © 1996 John Wiley & Sons, Inc.  相似文献   

2.
3.
The synthesis of functionalized fluorocooligomers based on chlorotrifluoroethylene (CTFE) and allyl glycidyl ether (AGE) under radical copolymerization is presented. The compositions of comonomers in the cooligomers were determined by three different analyses viz: from 1H and 19F NMR spectroscopy by using 1,3‐bis(trifluoromethyl) benzene as the external standard, epoxy equivalent weight value, and elemental analyses. The compositions determined by three methods were matching reasonably well and showed that the resulting poly(CTFE‐co‐AGE) cooligomers exhibit a tendency for alternation. The distribution of the monomers in the cooligomers was proposed based on the assessment of the reactivity ratios, ri, of both comonomers. These values were determined from the kinetics of radical copolymerization of CTFE with AGE from Fineman‐Ross, Kelen‐Tudos, and extended Kelen‐Tudos methods which led to the assessment of the average reactivity ratios as: rCTFE = 0.20 ± 0.03 and rAGE = 0.15 ± 0.08 at 74 °C. The lower Mn values substantiated the formation of cooligomers rather than copolymers. The formation of cooligomers was attributed to the chain transfer to AGE (by hydrogen abstraction from AGE) from the allylic transfer. The poly(CTFE‐co‐AGE) cooligomers were soluble in most of the common organic polar solvents. An optimization of cooligomer yields was investigated by using ethyl vinyl ether as a third comonomer and from different initiators. The thermal stabilities of the cooligomers, obtained by thermal gravimetric analysis, showed a 5% weight loss at temperatures over 225 °C under air. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3587–3595, 2010  相似文献   

4.
1-Butenyl glycidyl ether was prepared in high yield by the ruthenium-catalyzed isomerization of crotyl glycidyl ether. This ambifunctional monomer underwent facile photoinitiated cationic polymerization using diaryliodonium salts as photoinitiators. The progress of the polymerizations was followed using Fourier transform real-time infrared spectroscopy, and the reactivity of this monomer under various experimental conditions determined. A comparison of the rates of polymerization of the epoxy and vinyl ether groups suggested that the polymerization may take place by an intramolecular cyclization process that generates cyclic acetal units in the backbone of the polymer. It was further shown that crotyl glycidyl ether undergoes regioselective cationic ring-opening polymerization to give a polyether, and then isomerization was carried out to give an oligomer bearing reactive pendant 1-butenyl ether groups. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1179–1187, 1998  相似文献   

5.
The living/controlled copolymerization of methyl acrylate with 1‐alkenes and norbornene derivatives through several radical polymerization techniques has been achieved. These techniques include atom transfer radical polymerization, reversible addition–fragmentation transfer polymerization, nitroxide‐mediated polymerization, and degenerative transfer polymerization. These systems display many of the characteristics of a living polymerization process: the molecular weight increases linearly with the overall conversion, but the polydispersity remains low. Novel block copolymers have been synthesized through the sequential addition of monomers or chain extension. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 6175–6192, 2004  相似文献   

6.
以偶氮二异丁腈为引发剂,CuBr2/bpy为催化体系,甲基丙烯酸缩水甘油酯(GMA)通过反向原子转移自由基聚合反应合成了聚甲基丙烯酸缩水甘油酯(PGMA),其结构经1H NMR,IR和GPC确证。聚合反应符合活性自由基聚合特征,在聚合过程中GMA转化率和PGMA分子量随反应时间的延长而增大,分子量分布较窄。  相似文献   

7.
The linear ether bond was exclusively cleaved in benzyl glycidyl ether and triphenylmethyl glycidyl ether under the influence of K, K+(15-crown-5)2 (1), whereas the strongly strained three-membered oxacyclic ring remained undisturbed. Potassium glycidoxide and benzylpotassium were found as the primary reaction products of benzyl glycidyl ether with 1. Subsequently, benzylpotassium reacted with benzyl glycidyl ether giving the next potassium glycidoxide molecule and bibenzyl. Benzyl phenyl ether was used as a model compound to explain the mechanism of bibenzyl formation. The reaction of triphenylmethyl glycidyl ether with 1 resulted in potassium glycidoxide and stable triphenylmethylpotassium. After treating with a quenching agent a new glycidyl ether or glycidyl ester was obtained from potassium glycidoxide. These results were found when the reaction occurred at the excess of glycidyl ether. In another case, i.e. at the excess of 1 further reactions took place with the participation of potassium anions and various new compounds were observed in the reaction mixture after benzylation or methylation. Thus, the method of substrates delivery influences the course of studied processes in a decisive way.  相似文献   

8.
The ambifunctional monomer, 1-propenyl glycidyl ether, was prepared from allyl glycidyl ether, by a ruthenium-catalyzed isomerization reaction in high yield. 1-Propenyl glycidyl ether undergoes facile photoinduced cationic polymerization to yield a crosslinked polymer. The structure of this polymer was studied using 1H- and, 13C-NMR spectroscopies and employing well-characterized related polymers as models. The model polymers were prepared by the cationic polymerization of allyl glycidyl ether with BF3OEt2 followed by isomerization of the pendant allyl groups by a ruthenium catalyst. Subsequently, the resulting polyether-bearing pendant 1-propenyl ether groups was subjected to a diaryliodonium salt-photoinitiated polymerization. A comparison of the spectra of the polymers indicated the presence of cyclic acetal units in the polymer backbone. © 1994 John Wiley & Sons, Inc.  相似文献   

9.
A new green solvent, cyclopentyl methyl ether (CPME), is used for the first time in solvent mixtures for the successful supplemental activator and reducing agent atom transfer radical polymerization (SARA ATRP) of both activated and non‐activated monomers. The SARA ATRP of methyl acrylate (MA), glycidyl methacrylate (GMA), styrene (Sty), and vinyl chloride (VC) in CPME‐based mixtures is studied and presents similar features to those reported in the literature using other SARA ATRP systems. Moreover, CPME‐based mixtures are suitable solvents for the controlled SARA ATRP of MA using different SARA agents, such as Fe(0), Cu(0), or Na2S2O4. The chemical structure and the retention of the chain‐end functionality of the polymers are confirmed by 1H NMR and MALDI‐TOF analyses and the preparation of a well‐defined PMA‐b‐PVC‐b‐PMA triblock copolymer. The method reported here presents an additional improvement in the search for new ecofriendly ATRP systems. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2722–2729  相似文献   

10.
Addition of polyfluoroalkyl iodides to the double bond of allyl glycidyl ether occurred under mild conditions (20–25 °C, MeCN/H2O, Na2S2O4, NaHCO3) with retention of the oxirane ring. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1476–1478, August, 2007.  相似文献   

11.
Single‐electron transfer living radical polymerization (SET‐LRP) proceeds by an outer‐sphere single‐electron transfer mechanism that induces a heterolytic bond cleavage of the initiating and propagating R‐X (where X = Cl, Br, and I) species. Therefore, unlike the homolytic bond cleavage mechanism claimed for ATRP, SET‐LRP is expected to show a small dependence of the nature of the halide group on the apparent rate constant of activation. This means the R‐X with X = Cl, Br, and I must all be efficient initiators for SET‐LRP and no chain transfer must be observed in the case of initiators with X = Br and I. Here, we report the SET‐LRP of methyl acrylate initiated with the alkyl chlorides methyl‐2‐chloropropionate (MCP) and chloroform (CHCl3) and catalyzed by Cu(0)/Me6‐TREN/CuCl2 in DMSO at 25 °C. A combination of kinetic and structural analysis was used to elucidate the MCP and CHCl3 initiating behavior under SET‐LRP conditions, and to demonstrate the very small dependence of the SET‐LRP apparent rate constant of propagation on X while providing polymers with well defined architecture. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4917–4926, 2008  相似文献   

12.
This investigation reports the atom transfer radical copolymerization (ATRcP) of glycidyl methacrylate (GMA) and 2‐ethylhexyl acrylate (EHA). Poly(glycidyl methacrylate) (PGMA) has easily transformable pendant oxirane group and poly(2‐ethylhexyl acrylate) (PEHA) has very low Tg. They are the important components of coating and adhesive materials. Copolymerization of GMA and EHA was carried out in bulk and in toluene at 70 °C at different molar feed ratios using CuCl as catalyst in combination with 2,2′‐bypyridine (bpy) as well as N,N,N′,N″,N″‐pentamethyl diethylenetriamine (PMDETA) as ligand. The molecular weight (Mn) and the polydispersity index (PDI) of the polymers were determined by GPC analysis. The molar composition of the copolymers was determined by 1H NMR analysis. The reactivity ratios of GMA (r1) and EHA (r2) were determined using Finemann‐Ross and Kelen‐Tudos linearization methods and those had been compared with the literature values for conventional free radical copolymerization. The thermal properties of the copolymers were studied by DSC and TGA analysis. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6526–6533, 2009  相似文献   

13.
The unsaturated dimer of methyl acrylate [CH2C(CO2CH3)CH2CH2CO2CH3, or MAD] was copolymerized with various monomers to prepare copolymers bearing the ω-unsaturated end group [CH2C(CO2CH3)CH2 ] arising from β fragmentation of the MAD propagating radical. Copolymerizations of MAD with cyclohexyl and n-butyl acrylate resulted in copolymers with ω-unsaturated end groups, and increasing the temperature up to 180 °C resulted in an increase in the rate of β fragmentation of MAD radicals relative to propagation. Only a small amount of unsaturated end groups was introduced by copolymerization with ethyl methacrylate (EMA), and the EMA content in the copolymer increased with temperature. These findings could be explained by the reversible addition of the poly(EMA) radical to MAD. The copolymerization with ethyl α-ethyl acrylate (EEA) did yield a copolymer containing unsaturated end groups with MAD units as part of the main chain, although the steric hindrance of the ethyl group suppressed homopropagation and crosspropagation of EEA, resulting in low polymerization rates. Therefore, the copolymerization of MAD with acrylic esters at high temperatures was noted as a convenient route for obtaining acrylate–MAD copolymers bearing unsaturated end groups at the ω end (macromonomer). © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 597–607, 2004  相似文献   

14.
The anionic ring-opening copolymerization of commercially available bio-based cardanol glycidyl ether (CGE) was investigated without any prior purification. As a first step, anionic-ring-opening homopolymerization was attempted through active chain-end and monomer-activated mechanisms. Both strategies were unsuccessful. Conversely, in a second step, the anionic alternating ring-opening copolymerization (AAROP) of CGE with the renewable N-acetyl homocysteine thiolactone (NHTL) was successfully carried out in the presence of a strong base. Anisole, a solvent classified as sustainable and rarely used in anionic ring-opening polymerization, proved to be a suitable for the AAROP. This polymerization is an unusual example of synthesis of linear polyesters with cardanol-based monomers. The copolymers were carefully characterized by 1H, 13C, COSY, HSQC, 1H-15N NMR and MALDI-ToF, demonstrating an alternating structure. Then, CGE was copolymerized with NHTL and another additional epoxide. The cardanol-derived monomers enable the preparation of functionalizable poly(ester-alt-thioether) bearing multiple allyl and alkene groups. The AAROP method in anisole offers new opportunity for green anionic polymerization through the use of sustainable chemicals, witnessed by the valorization of cardanol-derived compounds and expands the scope of synthesized renewable polyesters.  相似文献   

15.
Functional aliphatic polycarbonate was synthesized by copolymerization of carbon dioxide and allyl glycidyl ether in the presence of a catalyst system based on ZnEt2 and pyrogallol at a molar ratio of 2 : 1. The polycarbonate obtained was oxidized with m‐chloroperbenzoic acid to give poly(epoxycarbonate). These polymers were degraded in an aqueous buffer of pH 7.4 at 37°C. Hydrolytic degradation was monitored by determination of the weight loss.  相似文献   

16.
Controlled free‐radical copolymerization of styrene (S) and butyl acrylate (BA) was achieved by using a second‐generation nitroxide, Ntert‐butyl‐N‐[1‐diethylphosphono‐(2,2‐dimethylpropyl)] nitroxide (DEPN), and 2,2‐azobisisobutyronitrile (AIBN) at 120 °C. The time‐conversion first‐order plot was linear, and the number‐average molecular weight increased in direct proportion to the ratio of monomer conversion to the initial concentration, providing copolymers with low polydispersity. The monomer reactivity ratios obtained were rS = 0.74 and rBA = 0.29, respectively. To analyze the convenience of applying the Mayo–Lewis terminal model, the cumulative copolymer composition against conversion and the individual conversion of each monomer as a function of copolymerization time were studied. The theoretical values of the propagating radical concentration ratio were also examined to investigate the copolymerization rate behavior. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4168–4176, 2004  相似文献   

17.
Bi-functional statistical copolymers, based on allyl methacrylate (AMA) and glycidyl methacrylate (GMA), were synthesized via atom transfer radical polymerization (ATRP). The polymerization reactions were carried out in a diphenyl ether solution at low temperature, 50 °C, using ethyl 2-bromoisobutyrate (EBrIB) as an initiator, and copper chloride with N,N,N′,N′′,N′′-pentamethyldiethylenetriamine (PMDETA) as the catalyst. Different aspects of the copolymerization, such as the kinetic behaviour, crosslink density and gel fraction were studied. The sol fractions of the synthesized copolymers were characterized by size exclusion chromatography (SEC) and nuclear magnetic resonance (NMR) spectroscopy. The reactivity ratios were calculated from the copolymer composition, determined by 1H NMR, and using the extended Kelen-Tüdös method. Values of 0.82 ± 0.04 and 1.22 ± 0.03 were obtained for AMA and GMA, respectively. The copolymer composition as a function of conversion degree for the different monomer molar fractions in the feed agreed with the theoretical values calculated from the Mayo-Lewis terminal model (MLTM).  相似文献   

18.
Cationic polymerization of n‐butyl propenyl ether (BuPE; CH3CH CHOBu, cis/trans = 64/36) was examined with the HCl–IBVE (isobutyl vinyl ether) adduct/ZnCl2 initiating system at −15 ∼ −78 °C in nonpolar (hexane, toluene) and polar (dichloromethane) solvents, specifically focusing on the feasibility of its living polymerization. In contrast to alkyl vinyl ethers, the living nature of the growing species in the BuPE polymerization was sensitive to polymerization temperature and solvent. For example, living cationic polymerization of IBVE can be achieved even at 0 °C with HCl–IBVE/ZnCl2, whereas for BuPE whose β‐methyl group may cause steric hindrance ideal living polymerization occurred only at −78 °C. Another interesting feature of this polymerization is that the polymerization rate in hexane is as large as in dichloromethane, much larger than in toluene. A new method in determining the ratio of the living growing ends to the deactivated ones was developed with a devised monomer‐addition experiments, in which IBVE that can be polymerized in a living fashion below 0 °C was added to the almost completely polymerized solution of BuPE. The amount of the deactivated chain ends became small in hexane even at −40 °C in contrast to other solvents. Thus hexane turned out an excellent solvent for living cationic polymerization of BuPE. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 229–236, 2000  相似文献   

19.
稳定自由基存在下苯乙烯聚合的加速剂   总被引:1,自引:0,他引:1  
研究了稳定自由基存在下苯乙烯的活性聚合,发现在β-酮酸酯-乙酰乙酸乙酯,乙二酸二乙酯,1,3-二酮-乙酰丙酮的少量存在下,苯乙烯聚合速率显著增加,分子量可控,分子量在布较窄。而乙酰丙酮较大量存在下,聚苯乙烯分散性稍微变宽。  相似文献   

20.
The living cationic polymerization of 5‐ethyl‐2‐methyl‐5‐(vinyloxymethyl)‐1,3‐dioxane ( 1 ), a vinyl ether with a cyclic acetal unit, was investigated with various initiating systems in toluene or methylene chloride at 0 to ?30 °C. With initiating systems such as hydrogen chloride (HCl)/zinc chloride (ZnCl2), isobutyl vinyl ether–acetic acid adduct [CH3CH(OiBu)OCOCH3]/tin tetrabromide (SnBr4)/di‐tert‐butylpyridine (DTBP), and CH3CH(OiBu)OCOCH3/ethylaluminum sesquichloride (Et1.5AlCl1.5)/ethyl acetate (CH3COOEt), the number‐average molecular weights (Mn's) of the obtained poly( 1 )s increased in direct proportion to the monomer conversion and produced polymers with relatively narrow molecular weight distributions [MWDs; weight‐average molecular weight/number‐average molecular weight (Mw/Mn) = 1.2–1.3]. To investigate the living nature of the polymerization with CH3CH(OiBu)OCOCH3/SnBr4/DTBP, a second monomer feed was added to the almost polymerized reaction mixture. The added monomer was completely consumed, and the Mn values of the polymers showed a direct increase against the conversion of the added monomer, indicating the formation of a long‐lived propagating species. The glass transition temperature and thermal decomposition temperature of poly( 1 ) (e.g., Mn = 13,600, Mw/Mn = 1.30) were 29 and 308 °C, respectively. The cyclic acetal group in the pendants of the polymer of 1 could be converted to the corresponding two hydroxy groups in a 65% yield by an acid‐catalyzed hydrolysis reaction. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4855–4866, 2007  相似文献   

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