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1.
The feasibility of the free-radical (co)polymerization of 2-[(diallyl)hydroxymethyl]pyrrolidine is studied. It is found that, under radical-initiation conditions, this monomer is not involved in homopolymerization and copolymerization with vinyl monomers; however, it exhibits high activity during copolymerization with sulfur dioxide. Copolymerization proceeds to yield alternating copolymers of an equimolar composition. The main polymer chain contains both linear fragments formed via opening of one double bond of 2-[(diallyl)hydroxymethyl]pyrrolidine and cyclolinear structures resulting from the participation of two double bonds in the reaction. It is demonstrated that the copolymers obtained are optically active.  相似文献   

2.
The radical terpolymerization of sulfur dioxide, styrene, and methyl methacrylate in o-dichlorobenzene with 2,2′-azobisisobutyronitrile was carried out in order to clarify the propagation mechanism of the radical copolymerization of sulfur dioxide and styrene, especially as a function of total concentration of sulfur dioxide and styrene. From the analysis of the trigonal composition diagrams it has been definitely shown that the radical copolymerization of sulfur dioxide and styrene proceeds by the propagation of two monomers, but the usual type of copolymerization mechanism, explicable in terms of the Lewis-Mayo equation, is not applicable to this copolymerization. The participation in the propagation of a monomer charge-transfer complex consisting of sulfur dioxide and styrene was also ruled out.  相似文献   

3.
Activity of azanorbornenes: N-benzyl-2-azanorborn-5-ene, (2-azanorborn-5-en-2-yl)methyl acetate, and N-allyl-2-azanorborn-5-ene in radical homo-and copolymerization with vinyl monomers and sulfur dioxide was studied.  相似文献   

4.
Summary: Methods for the synthesis of new diallylaminophosphonium salts have been developed. The reactivity of tris(diethylamino)diallylaminophosphonium tetrafluoroborate (DAAP-BF4) and chloride (DAAP-Cl) through free-radical copolymerization with sulfur dioxide have been studied. Diallylaminophosphonium salts do not undergo free radical homopolymerization but copolymerize at a low rate with vinyl monomers. DAAP-BF4 and DAAP-Cl show high activity in copolymerization with sulfur dioxide. The structure of the polysulfones obtained has been identified by NMR 13C. The investigations carried out have shown that DAAP-BF4 and DAAP-Cl copolymerize with sulfur dioxide, both double bonds participating with formation of cis-, trans-stereoisomeric pyrrolidine structures in a cyclolinear polymer chain. The new polysulfones possess a broad spectrum of bactericidal effect.  相似文献   

5.
The activity of diallylamido-bis(diethylamido)guanidinium chloride in radical polymerization and copolymerization with vinyl monomers giving rise to random copolymers has been studied. A lower activity of diallylamido-bis(diethylamido)guanidinium chloride than that of vinyl monomers has been demonstrated. It has been shown that this monomer readily copolymerizes with sulfur dioxide and alternating copolymers of equimolar composition are formed regardless of the comonomer ratio in the initial mixture and the reaction conditions (the nature of solvent and initiator, temperature, and conversion). The structure of polymers has been studied by 13C NMR spectroscopy.  相似文献   

6.
The monomer reactivity in the complexed copolymerization of vinyl compounds with alkylaluminum halides has been extensively surveyed. Equimolar copolymers were obtained in various combinations of monomers which are classified into two monomer groups, A and B. The group B monomers are conjugated vinyl compounds having nitrile or carbonyl groups in the conjugated position and form complexes with alkylaluminum halides. The group A monomers are donor monomers having low values, such as olefins, haloolefins, dienes, and unsaturated esters. These A monomers belong to the same group of monomers which give alternating copolymers in conventional radical copolymerization with maleic anhydride, SO2, and so on. In addition the complexed copolymerization has the same specific characteristics as the conventional alternating copolymerization, i.e., high reactivities of allyl-resonance monomers and inner olefins and no transfer of halogen atom to the copolymers in CCl4. These features suggest little or no participation of the A monomer radical. The Q-e scheme is also discussed in terms of the monomer reactivity. More than two monomers selected from groups A and B give multicomponent copolymers in which alternating sequential structures hold with respect to A and B. Anomalous mutual reactivities between two B monomers in the terpolymerization were observed and indicate that the nature of radical in the complexed copolymerization may be different from that expected by the Lewis-Mayo equation. The complexed radical mechanism previously proposed is discussed in connection with the specific behavior mentioned above.  相似文献   

7.
1-Methylcyclopropene (MCP) copolymerizes rapidly with acrylic and vinyl monomers to form soluble, high molecular weight products containing enchained cyclopropane rings. The high electron availability in the cyclopropene double bond promotes one-to-one alternating copolymerization with sulfur dioxide, maleic anhydride, acrylic acid, acrylonitrile, dialkyl fumarates and acrylic esters. Nonalternating copolymers are obtained with vinyl chloride and vinyl acetate, and attempted copolymerization fails entirely with styrene, α-methylstyrene and isoprene. This pattern of copolymerization reactivity resembles that of highly compressed ethylene. Methylcyclopropene copolymers have high glass temperatures in spite of the small size of the MCP unit. The combination of high Tg and small size allows preparation of copolymers with high Tg having a wide range of ductilities and cohesive energy densities.  相似文献   

8.
Although ortho-esters constitute a well-known class of organic compounds, the orthoacrylates were unknown prior to a report from these laboratories in 1972. To date, this novel class of acrylic esters has not been investigated as polymerization monomers. We report here polymerization and copolymerization studies of representative members of this class of compounds. Although the orthoacrylates studied did not polymerize in the presence of conventional cationic initiators nor radical initiators, they did respond to radical-initiated copolymerization with a variety of conventional vinyl monomers. Their corresponding reactivity ratios were determined, as well as the Q and e parameters. Monomer syntheses and characterization are reported, as well as structural and properties studies on the copolymers.  相似文献   

9.
The involvement of fullerene in the radical copolymerization of diallyl isophthalate with methyl methacrylate or styrene results in a change in the relative activity of monomers owing to the interaction of C60 with the allyl radical yielding a “quo;new,”quo; more active radical. This corresponds to the transition from degradative chain transfer to effective transfer to the allyl compound. It is of great importance that, at an amount of diallyl isophthalate in the monomer mixture of up to 10 mol %, C60 fullerene is almost completely incorporated into macromolecules.  相似文献   

10.
本文引用50多篇文章,按引发方式不同从顺序引发剂,imiferter法,高分子引发剂法和自由基性聚合等几方面综述了自由基嵌段共聚合近10年来的新进展。  相似文献   

11.
Three new vinyl ether monomers containing phosphonate moieties were synthesized from transetherification reaction. We showed that the yield was dependent on the spacer length between the vinyl oxy group and the phosphonate moieties: when the spacer is a single methylene side reaction may occur, leading to the formation of acetal compounds. Free‐radical copolymerizations of phosphonate‐containing vinyl ether monomers with maleic anhydride were carried out, leading to alternated copolymers of rather low molecular weights (from 1000 to 7000 g/mol). Both gel permeation chromatography and 31P NMR analyses enhanced possible intramolecular transfer reactions occurring from the phosphonate moieties. Kinetic investigation showed that the electron‐withdrawing character of the phosphonate moieties tends to decrease the rate of copolymerization. Nevertheless, almost complete monomers conversion was reached after 30 min of reaction with dimethyl vinyloxyethylphosphonate (VEC2PMe). Then, radical copolymerization of VEC2PMe with a series of electron‐accepting monomers, that is, dibutyl maleate, dibutylitaconate, itaconic anhydride, butyl maleimide, and methyl maleimide, led to a series of alternated copolymers. From kinetic investigation, we showed that the higher the electron‐accepting effect, the faster the vinyl ether consumption and the higher the molecular weights. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

12.
Functional poly(diene sulfone)s are prepared by the radical alternating copolymerization of 1,3‐diene monomers containing an ester substituent with sulfur dioxide. Methyl 3,5‐hexadienoate (MH) and methyl 5,7‐octadienoate (MO) with both an alkylene spacer and a terminal diene structure are suitable to produce a high‐molecular‐weight copolymer in a high yield, while the copolymerization of 5,7‐nonadienoic acid, ethyl 2,4‐pentadienoate, and ethyl 4‐methyl‐2,4‐pentadienoate including either an alkylene spacer or a terminal diene structure lead to unsuccessful results. The 13C NMR chemical shift values of MH and MO suggest a high electron density at their reacting α‐carbon for exhibiting a high copolymerization reactivity. Fluorene‐containing diene monomers, 9‐fluorenyl 3,5‐hexadienoate (FH) and 9‐fluorenyl 5,7‐octadienoate (FO), are also prepared and copolymerized with sulfur dioxide. The thermal and optical properties of the poly(diene sulfone)s containing the methyl and fluorenyl ester substituents in the side chain are investigated. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1000–1009  相似文献   

13.
The radical copolymerization of sulfur dioxide and chloroprene (CP) in benzene was carried out, especially as a function of the total monomer concentration ([SO2] + [CP]). The composition of chloroprene polysulfones varies mainly with total monomer concentration and with polymerization temperature, but depends very slightly on feed composition. The microstructure of chloroprene units in chloroprene polysulfone was such that the trans-1,4 unit was predominantly over the cis-1,4 unit. Thus it would seem possible to rule out both radical copolymerization mechanisms, i.e., propagation of separate monomers as explained by the Lewis-Mayo equation, and propagation processes involving a monomer charge-transfer complex.  相似文献   

14.
(2-Oxo-1,3-dioxolan-4-yl) methyl vinyl ether (OVE) was synthesized with high yield by addition reaction of glycidyl vinyl ether with carbon dioxide using tetrabutylammonium bromide (TBAB) as a catalyst. OVE was also prepared by reaction with β-butyrolactone or sodium hydrogencarbonate in the presence of TBAB as the catalyst. Poly [(2-oxo-1,3-dioxolan-4-yl) methyl vinyl ether] [P(OVE)] was obtained with high yield by cationic polymerization of OVE catalyzed using boron trifluoride diethyl ether complex in dichloromethane. Polymers bearing pendant 5-membered cyclic carbonate groups were also prepared by radical copolymerization of OVE with some electron-accepting monomers. Furthermore, addition reaction of P(OVE) with alkyl amines yielded the corresponding polymer having pendant 2-hydroxyethyl carbamate residue with high conversions. © 1994 John Wiley & Sons, Inc.  相似文献   

15.
The inherent differences in reactivity between activated and non‐activated alkenes prevents copolymerization using established polymer synthesis techniques. Research over the past 20 years has greatly advanced the copolymerization of polar vinyl monomers and olefins. This Review highlights the challenges associated with conventional polymerization systems and evaluates the most relevant methods which have been developed to “bridge the gap” between polar vinyl monomers and olefins. We discuss advancements in heteroatom tolerant coordination–insertion polymerizations, methods of controlling radical polymerizations to incorporate olefinic monomers, as well as combined approaches employing sequential polymerizations. Finally, we discuss state‐of‐the‐art stimuli‐responsive systems capable of facile switching between catalytic pathways and provide an outlook towards applications in which tailored copolymers are ideally suited.  相似文献   

16.
Radical copolymerization of N,N-diallyl-N′-benzoylhydrazine with acrylonitrile and sulfur dioxide was studied. The kinetic features of the copolymerization of these systems were examined, the relative activities of the monomers were determined, and the structure of the resulting copolymers was elucidated.  相似文献   

17.
异丁基乙烯基醚与受电子单体的可控自由基共聚合   总被引:3,自引:0,他引:3  
近年来发展起来的“活性” 可控自由基聚合越来越为人们所关注 ,其原因在于采用这种方法不仅可以设计聚合物的分子量 ,得到窄分布聚合物 ,而且聚合条件不象活性离子型聚合那样严格 ,单体适用范围相对较广 .关于烯类单体的活性自由基聚合迄今主要有 :氮氧自由基调控的稳定自由基聚合 (Stablefreeradicalpolymerization ,简称SFRP) [1] 、原子转移自由基聚合 (Atomtransferradicalpolymerization ,简称ATRP) [2 ] 以及以后发展起来的自由基可逆加成 断链链转移聚合…  相似文献   

18.
The kinetic behavior of the 60Co-initiated copolymerization at 25°C of styrene with vinyl acetate at 1100 and 2000 rad/hr was studied. As in the case of thermal and photochemical copolymerizations of these monomers, the growing chains are particularly rich in styrene units, and the overall rate is affected by a diluent effect due to the vinyl acetate monomer. However, in the case of the radiation copolymerization, this effect is partially counterbalanced by an increase of the initiation rate with the vinyl acetate concentration; the polymerization rate curve shows a maximum at a vinyl acetate molar fraction of 0.25. This effect is due to the very different free radical yields of these two monomers. The experimental results may be understood on the basis of a kinetic scheme which involves an energy transfer process from the excited vinyl acetate molecules to the styrene monomer and a termination reaction of the growing chains by very short styrene radicals when the mixture is rich in vinyl acetate.  相似文献   

19.
Radical copolymerization of sulfur dioxide and vinyl chloride (VC) has been studied by the comparison of the composition of copolymers obtaining from different reaction conditions, i.e., reaction temperatures, feed compositions, and total monomer concentrations. The composition of VC in copolymer is independent of comonomer composition except at high concentration of VC in feed; it increases with increasing reaction temperature or decreasing total monomer concentration. At lower temperature, the composition of copolymer becomes independent of total monomer concentration. The overall rate of polymerization is proportional to [VC]1,7 and [SO2]0.5. These results were compared with those obtained in our previous study on the SO2-styrene copolymerization. A propagation mechanism for radical copolymerization of SO2 and VC is also proposed.  相似文献   

20.
In the cyclocopolymerizations of diallyl phthalate (DAP) with monovinyl monomers the reactivity ratio of the cyclized radical, rc, was smaller than that of the uncyclized radical, r1; this was ascribed to steric hindrance in the addition reaction of the cyclized radical with DAP. In this paper, the validity of the values of rc and r1 is discussed on the basis of model experiments, i.e., the copolymerization of DAP in dilute solution corresponding to rc and that of allyl propyl phthalate, to r1. The copolymerizations of methyl allyl phthalate and allyl octyl phthalate with vinyl acetate are also presented.  相似文献   

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