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1.
A series of copolymers of N,N‐dialkyl‐N‐2‐(methoxycarbonyl)allyl allyl ammonium chloride, N,N‐dialkyl‐N‐2‐(ethoxycarbonyl)allyl allyl ammonium chloride, and N,N‐dialkyl‐N‐2‐(t‐butoxycarbonyl)allyl allyl ammonium bromide with diallyldimethylammonium chloride (DADMAC) were prepared in water at 60 °C with 2,2′‐azo‐bis(2‐amidinopropane)dihydrochloride. A strong effect of ester substituents on cyclopolymerization was observed. The methyl and ethyl ester monomers showed high cyclization efficiencies during homopolymerizations and copolymerizations. Unexpectedly, the t‐butyl ester derivatives showed high crosslinking tendencies. Water‐soluble copolymers were obtained only with a decrease in the molar fraction of t‐butyl ester monomer below 30%. Relative reactivities of the allyl‐acrylate monomers in photopolymerizations were compared with the relative reactivity of DADMAC. Allyl‐acrylate monomers were much more reactive than DADMAC; the photopolymerization rate decreased in the following order: N,N‐morpholine‐N‐2‐(t‐butoxycarbonyl)allyl allyl ammonium bromide > N,N‐piperidyl‐N‐2‐(t‐butoxycarbonyl)allyl allyl ammonium bromide > N,N‐dibutyl‐N‐2‐(ethoxycarbonyl)allyl allyl ammonium chloride > N,N‐piperidyl‐N‐2‐(ethoxycarbonyl)allyl allyl ammonium chloride ∼ N,N‐morpholine‐N‐2‐(ethoxycarbonyl)allyl allyl ammonium chloride ∼ N,N‐piperidyl‐N‐2‐(methoxycarbonyl)allyl allyl ammonium chloride > N‐methyl‐N‐butyl‐N‐2‐(ethoxycarbonyl)allyl allyl ammonium chloride. Intrinsic viscosities of the polymers measured in 0.09 M NaCl ranged from 1.06 to 3.20 dL/g. The highest viscosities were obtained for copolymers of the t‐butyl ester monomers with piperidine and morpholine substituents. The copolymer of the t‐butyl ester with piperidine substituent and DADMAC was hydrolyzed in acid to give a polymer with zwitterionic character. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 640–649, 2001  相似文献   

2.
Novel allyl‐acrylate quaternary ammonium salts were synthesized using two different methods. In the first (method 1), N,N‐dimethyl‐N‐2‐(ethoxycarbonyl)allyl allylammonium bromide and N,N‐dimethyl‐N‐2‐(tert‐butoxycarbonyl)allyl allylammonium bromide were formed by reacting tertiary amines with allyl bromide. The second (method 2) involved reacting N,N‐dialkyl‐N‐allylamine with either ethyl α‐chloromethyl acrylate (ECMA) or tert‐butyl α‐bromomethyl acrylate (TBBMA). The monomers obtained with the method 2 were N,N‐diethyl‐N‐2‐(ethoxycarbonyl)allyl allylammonium chloride, N,N‐diethyl‐N‐2‐(tert‐butoxycarbonyl)allyl allylammonium bromide, and N,N‐piperidyl‐N‐2‐(ethoxycarbonyl)allyl allylammonium chloride. Higher purity monomers were obtained with the method 2. Solution polymerizations with 2,2′‐azobis(2‐amidinopropane) dihydrochloride (V‐50) in water at 60–70°C gave soluble cyclopolymers which showed polyelectrolyte behavior in pure water. Intrinsic viscosities measured in 0.09M NaCl ranged from 0.45 to 2.45 dL/g. 1H‐ and 13C‐NMR spectra indicated high cyclization efficiencies. The ester groups of the tert‐butyl polymer were hydrolyzed completely in acid to give a polymer with zwitterionic character. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 901–907, 1999  相似文献   

3.
The binary radical copolymerization of acrylic acid amides (acrylamide and N-cyclohexen-1-ylacrylamide) with alkenyl halides (vinyl chloride, vinyl bromide, and allyl chloride) has been studied. The constants of relative activity of the monomers used are calculated. For the systems under investigation, the occurrence of dehydrochlorination of a polymer chain and protonation of a carbonyl group occur is confirmed. Allyl chloride shows the most pronounced tendency toward dehydrochlorination, while in the case of vinyl chloride, this tendency is the least distinct. The polymer-analogous transformations result in copolymers containing polyene fragments and units of ammonium or oxonium amide salts.  相似文献   

4.
Radical copolymerization of 2,2-diallyl-1,1,3,3-tetraethylguanidinium chloride with methyl methacrylate and allyl methacrylate in the bulk and methanol solution in the presence of azobis-isobutyric acid dinitryle at 70–90°C has been studied. Copolymerization of 2,2-diallyl-1,1,3,3-tetraethylguanidinium chloride with methyl methacrylate or allyl methacrylate in the bulk proceeds with formation of random copolymers enriched in methacrylate units; in the copolymerization of 2,2-diallyl-1,1,3,3-tetraethylguanidiny chloride with methyl methacrylate in methanol, the copolymerization constants of the monomers become close. The kinetic parameters of the reaction have been studied, the relative activities of the monomers have been determined. It has been found that 2,2-diallyl-1,1,3,3-tetraethylguanidinium chloride is copolymerized with allyl methacrylate or methylmethacrylate to form pyrrolidinium structures in the cyclolinear polymer chain. At high degrees of conversion of the copolymerization of 2,2-diallyl-1,1,3,3-tetraethylguanidinium chloride with allyl methacrylate, the viscosity increases and the side polymer chains are crosslinked by “allyl bonds” to form insoluble copolymers, swelling in benzene and DMSO.  相似文献   

5.
This investigation deals with the free radical polymerization both of (2-methacryloyloxy-ethyl) trimethyl ammonium chloride (QACEMA) and of diallyldimethyl ammoniumcbloride (DADMAC) in inverse emulsion. The influences of some factors, such as theconcentration of monomers, initiator and emulsifier are discussed. The polymerization rateequations of above two monomers can be written as follows:R_p= k[M]~(1.21) [I]~(0.82) [E]~(0.57) (for QACEMA)R_p= k'[M]~(1.34) [I]~(0.90)[E]~(0.62)(for DADMAC)  相似文献   

6.
Poly(allyl stearate) and selected copolymers and terpolymers modified by allyl stearate were investigated in this work. The systems selected and studied over a wide range of composition, included copolymers with vinyl stearate and with vinyl chloride, and terpolymers containing vinyl chloride and allyl stearate, modified further by vinyl stearate or vinyl acetate. Copolymers of allyl stearate and vinyl stearate were studied incrementally across the range of composition. In the ester copolymers the effect of degradative chain transfer on crystallization and solution properties was studied. A relation was obtained between intrinsic viscosities and number-average molecular weights; a shift in molecular weight distribution with increase in allyl component was demonstrated. The crystallinity contributed by the side chains was shown to be characterized by isomorphic replacement regardless of molecular weight. Mechanical properties of internally plasticized copolymers of allyl stearate and vinyl chloride, in a limited composition range, were compared with corresponding data for copolymers of vinyl stearate and vinyl chloride. While molecular weight reduction of the allylic copolymers exceeded that for the vinyl ester system, the effect, in the useful plasticization composition range, was not enough to grossly affect ultimate properties. The glass transitions of the hypothetical amorphous homopolymers of both fatty esters were estimated to be the same. Because this Tg was low (ca. ?110°C), only relatively small mole fractions of allyl stearate were needed for effective plasticization. Isochronal temperature–composition diagrams also showed both systems to be essentially identical, but marked differences were found for diluent mixtures incorporating di-2-ethylhexyl phthalate (DOP). An empirical equation, previously derived, adequately predicted the decline in degree of polymerization with increase in allyl stearate between the limits of the respective homopolymers for all copolymers studied. Terpolymers followed the trends of the copolymers and offered no special property advantage.  相似文献   

7.
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   

8.
For many industrial applications, the combination of two different monomers in statistical or diblock copolymers enhances the properties of the corresponding polymer. However, during the polymerization reaction, homopolymers might be formed and can influence the properties for the applications. Consequently, the separation and the quantification of the homopolymers contained in copolymer samples are crucial. In addition, the charge density distribution of the statistical copolymer is an important characteristic for the applications. The purpose of this work was to study the characterization of a statistical copolymer of acrylic acid (AA) and diallyldimethyl ammonium chloride (DADMAC) by capillary electrophoresis (CE) in acidic conditions (cationic copolymers). For that purpose, a free solution electrophoretic separation was carried out according to the charge rate (chemical composition) independently of the molar mass. The second objective was to compare contactless conductivity detection and indirect UV absorbance modes for the quantification of DADMAC homopolymers present in copolymer samples. Different coated capillaries based on neutral or positively charged modification were also compared. The comparison of indirect absorbance UV and contactless conductimetric detection demonstrated that both detection modes can be used for a complete CE characterization of non-UV absorbing PAA-DADMAC copolymers.  相似文献   

9.
Diallyldimethylammonium chloride (DADMAC) was free-radical copolymerized with acrylamide (AA) in water at a total monomer concentration of 4 mol/L and 40°C with different monomer feed compositions. Gelation occurred only for 20/80 DADMAC/AA monomer feed although crosslinking was observed for all monomer feed compositions. The gel point was at 51% conversion, and the swelling ratios of the resulting gels were quite high, from 1400 to 700. Addition of 2‐propanol as a chain‐transfer reagent reduced crosslinking and prevented gelation. These results are mechanistically discussed in connection with the cyclopolymerizability of DADMAC, and significant allylic hydrogen abstraction by the growing polymer radical characteristic of allyl polymerization is proposed.  相似文献   

10.
Temperature sensitive poly{N‐[3‐(dimethylaminopropyl)]methacrylamide‐co‐acrylamide} [P(DMAPMA‐co‐AAm)] hydrogels were prepared by the free‐radical crosslinking copolymerization of corresponding monomers in water with N,N‐methylenebisacrylamide as the crosslinker, ammonium persulfate as the initiator, and N,N,N′,N′‐tetramethylethylenediamine as the activator. The swelling equilibrium of the P(DMAPMA‐co‐AAm) hydrogels was investigated as a function of temperature in aqueous solutions of the anionic surfactant sodium dodecyl sulfate and the cationic surfactant dodecyltrimethylammonium bromide. In pure water, regardless of the amount of N,N‐methylenebisacrylamide, the P(DMAPMA‐co‐AAm) hydrogels showed a discontinuous phase transition between 30 and 36 °C. However, the transition temperature changed from discontinuous to continuous with the addition of surfactants; this was ascribed to the conversion of nonionic P(DMAPMA‐co‐AAm) hydrogels into polyelectrolyte hydrogels due to the binding of surfactants through hydrophobic interactions. Additionally, the concentrations of free sodium dodecyl sulfate and dodecyltrimethylammonium bromide ions were measured at different temperatures by conductometry, and it was found that the electric conductivity of the P(DMAPMA‐co‐AAm)–surfactant systems depended strongly on the swelling ratio; most notably, it changed drastically near the phase‐transition temperature of the P(DMAPMA‐co‐AAm) hydrogel. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 1645–1652, 2006  相似文献   

11.
采用γ辐射溶液聚合法合成了几种二甲基二烯丙基氯化铵 丙烯酸 (DADMAC AA)共聚凝胶 .实验结果表明单位体积溶液中二组分单体总摩尔数和丙烯酸 (AA)相对含量的增加使共聚凝胶力学强度明显增高 .在两种单体等摩尔比的情况下共聚体的凝胶含量随剂量增加而增加 ,且明显高于聚N ,N′ 二甲基二烯丙基氯化铵 (PolyDADMAC)凝胶 .体系中少量κ 卡拉胶 (KC)的加入可增强共聚凝胶韧性但对凝胶含量和强度影响甚微 .共聚凝胶溶胀性能测定结果表明DADMAC与AA摩尔比为 1∶2时凝胶溶胀比与体系pH值的关系呈现聚两性电解质性质 ,等电点pH值接近 4 5 .这种聚两性电解质性质在对铼Re(Ⅶ )离子浓集中也有所表现  相似文献   

12.
Poly(1,1‐bis(ethoxycarbonyl)‐2‐vinyl cyclopropane (ECVP)‐graft‐dimethyl siloxane) copolymers were prepared using a macromonomer approach. Poly(dimethyl siloxane) (PDMS) macromonomers were prepared by living anionic polymerization of cyclosiloxanes followed by sequential chain‐end capping with allyl chloroformate. These macromonomers were then copolymerized with ECVP. MALDI‐ToF mass spectrometry and 1H NMR spectroscopy were used to show that the macromonomers had approximately 80% of the end groups functionalized with allyl carbonate groups. Gradient polymer elution chromatography showed that high yields of the graft copolymers were obtained, along with only small fractions of the PECVP and PDMS homopolymers. Differential scanning calorimetry showed that the low glass transition temperature (Tg) of the PDMS component could be maintained in the graft copolymers. However, the Tg was a function of polymer composition and the polymers produced had Tgs that ranged from ?50 to ?120 °C. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013  相似文献   

13.
生物膜是由磷脂双分子层构成的基质和镶嵌或包埋在基质中的蛋白质所组成,脂质体与生物膜结构相似,但一般是热力学不稳定体系,为改善脂质体的稳定性,近年合成和制备了许多不饱和脂质体单体化合物和聚合脂质体。  相似文献   

14.
Coordination-insertion copolymerization of allyl monomers with ethylene was developed by using a palladium/phosphine-sulfonate catalyst. A variety of allyl monomers, including allyl acetate, allyl alcohol, protected allylamines, and allyl halides, were copolymerized with ethylene to form highly linear copolymers that possess in-chain -CH(2)CH(CH(2)FG)- units.  相似文献   

15.
A highly effective phase transfer of a quaternary ammonium gemini surfactant with ester groups((diethylhexanedioate) diyl-a,v-bis(dimethyl dodecyl ammonium bromide) referred to as 12-10-12)was synthesized with high yield and characterized by infrared spectroscopy, elemental analysis and1 HNMR. Then, 12-10-12 was used as a phase transfer catalyst to study the catalytic effect on the reaction of anhydrous sodium acetate and 4-methylbenzyl chloride. The possible catalytic mechanism and the influence of surfactant concentration, temperature and type are also discussed. The experimental results showed that the catalysis efficiency was more active than the traditional, single-chained surfactant,tetrabutyl ammonium bromide. It also revealed that the reaction was first-order with respect to the concentration of 4-methylbenzyl chloride. The concentration of 4-methylbenzyl chloride grew linearly with the concentration of 12-10-12 and as the reaction temperature increased. The optimum reaction time was 7 h.  相似文献   

16.
A mixture of N- and O-alkylation products is formed in the reaction of 1,2,3,4,10,-10a-hexahydropyrimido[1,2-a]indol-2-ones with ethyl iodide, allyl bromide, or benzyl chloride in DMFA (dimethylformamide) in the presence of potassium hydroxide. In the presence of aqueous solutions of acids with subsequent treatment with bases, the alkylation products are converted to 1-[2-(alkoxycarbonyl)-ethyl]-2-methylene-2,3-dehydro-1H-indoles. The reaction of 1,2,3,4,10,10a-hexahydropyrimido[1,2-a]indol-2-one with triethyloxonium fluoroborate gives 1-[2-(ethoxycarbonyl)ethyl]-2-methylene-2,3-dihydro-1H-indole.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1224–1227, September, 1989.  相似文献   

17.
手性季铵盐作为相转移催化剂(Phase-transfer catalysts ,PTC) 能使非均相反应在温和条件下进行,操作简单,反应速率加快,产率明显提高,因此这一技术在有机合成中具有广泛的应用.这些季铵盐主要是以金鸡钠生物碱衍生的[1,2],近年来出现了一些其它类型的季铵盐[3],但是它们的制备一般比较困难,大多数催化效果不是很理想;并且这些季铵盐的结构有一定局限,改造比较困难.同时这些季铵盐大都是 C-手性的,很少有N-手性的[4,5];在以前的不对称反应中,有意识地构建N-手性季铵盐及N-手性在不对称反应中的作用鲜有报道[6].  相似文献   

18.
The reaction of 5-anilino(toluidino-, morpholino)-1,3,4-thiadiazoline-2-thiones at 80°C with allyl bromide and benzyl chloride in alcohol, acetonitrile or DMF in the presence of KOH and also with phenoxymethyloxirane in alcohol in the absence of base gives the corresponding novel allyl-, benzyl-, and 2-hydroxy-3-phenoxypropyl products substituted at the exocyclic S atom. Alkylation of the indicated thiones with benzyl chloride at 150-153°C in DMF in the presence of KOH occurs similarly. Under these conditions, allyl bromide forms alkylation products at the endocyclic N(3) atom as a result of an SN thio-Claisen rearrangement of the initially formed product which is allyl substituted at the exocyclic S atom.  相似文献   

19.
In this study, three hydrophilic monomers; 2-acrylamido-2-methyl-1-propanesulfonic acid, 2-hydroxyethyl methacrylate, diallyldimethylammonium chloride (DADMAC) were selected and their performance as an antistatic finish on nylon 6,6 fabrics was investigated. A non-thermal, high density atmospheric pressure plasma was used to graft polymerize the monomers on nylon 6,6 fabrics. Fabrics were first treated with solutions of monomer in water, air dried and then treated with helium plasma to graft polymerize the monomer on the fiber surface. Surface resistivity values were measured before and after soxhlet extraction with water. Results showed that the DADMAC monomer provided better antistatic properties to fabrics. Further studies with DADMAC monomer were made; effects of plasma post exposure time, plasma pre-exposure time, plasma power, concentration of the monomer and existence of a crosslinker were investigated. Higher plasma power, higher concentration of the monomer and longer post exposure times all gave better antistatic properties to the nylon 6,6 fabrics. Acid dye staining, UV–Vis and FT-IR measurements were conducted and results confirmed a grafted poly-DADMAC layer on the fabric surface.  相似文献   

20.
The radical polymerization of tetraallyl ammonium chloride (TAAC) was carried out in water using azo-initiator as compared to that of diallyl dimethyl ammonium chloride (DADMAC); the rate of polymerization was quite low for TAAC, around one-third of DADMAC. Kinetic discussion revealed the importance of degradative chain transfer in the polymerization of TAAC. The cyclopolymerizability of TAAC was estimated kinetically as the ability of 5-membered monocyclic radical to form a bicyclic ring, giving the cyclization constant of 21 mol/L at [M] = 2 mol/L. Gelation occurred at around 20% conversion.  相似文献   

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