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1.
Summary The preparation of p-styrenesulfonic and methacrylic acid esters of the microbiocides 2, 4, 6-trichlorophenol and 4-chloro-m-cresol, and their characterization by IR, 1H and 13C NMR spectroscopy are described. The radical homopolymerization of the biocidal monomers, and their copolymerization with various vinyl monomers have been studied. The polymerization gives polymers in which the microbiocide moieties are covalently attached to the polymer backbone chain by ester links. 相似文献
2.
Nitroalkyl acrylates and methacrylates involving some new compounds were prepared. The homopolymerization of these monomers in toluene and their copolymerization with styrene in acetone were carried out with azobisisobutyronitrile as initiator. The rate of polymerization of the nitroalkyl acrylates showed a correlation with the number of nitro groups situated on the ester side chain. The apparent activation energies of the polymerization were found to be 22.0–27.5 kcal./mole for the nitroalkyl acrylates and about 11.5–13.0 kcal./mole for the nitroalkyl methacrylates. From the reactivity ratios and Q-e values of the copolymerization the following information was obtained. The copolymerization behavior of nitroalkyl acrylates and methacrylates showed an alternating tendency, and these monomers belong to the conjugative monomer groups. On the reactivities of these monomers, the polarity of vinyl group was affected a little by nitro group of ester bond side, and the resonance affected little. These monomers were crosslinked with 2-methyl-2-nitro-1,3-propylene diacrylate. Some of the polymers showed marked improvement in the physical properties of elastomers. 相似文献
3.
Qianhui Lee David JT Hill Tri Le Firas Rasoul Andrew K Whittaker 《Polymer International》2009,58(4):348-353
BACKGROUND: Copolymers of acrylic acid (AA) are important materials for the preparation of glass ionomer cements. Copolymerisation of AA is widely used to alter the acid strength of the material and to increase the number of salt bridges formed in cements. In this paper we report the copolymerisation of AA with n‐butyl vinyl ether (BVE) to form unique copolymers of the hemiacetal ester and with BVE incorporated into the main chain. RESULTS: AA and BVE undergo a spontaneous reaction to form a hemiacetal ester which can itself undergo free radical copolymerisation. The kinetics of this reaction in the bulk state have been examined. In addition, under these conditions BVE is incorporated into the polymer main chain via a free radical mechanism. CONCLUSION: Novel copolymers of the hemiacetal ester and BVE have been prepared in this study. The hemiacetal side chains are labile under moderate heating, being converted back to the acid analogue. Copyright © 2009 Society of Chemical Industry 相似文献
4.
Hideharu Mori Yosuke Saito Eri Takahashi Kazuhiro Nakabayashi Atsuhiko Onuma Makoto Morishima 《Reactive and Functional Polymers》2013,73(4):658-667
Novel organic–inorganic hybrids with sulfonic acid groups were prepared using random copolymers composed of vinyl sulfonate esters and vinyl trialkoxysilanes. Five vinyl sulfonate esters with different substituent groups were employed as protecting monomers for the production of the poly(vinyl sulfonic acid) component, and three vinyl trialkoxysilanes were used as cross-linkable monomers. Free radical and reversible addition-fragmentation chain transfer (RAFT) copolymerizations were performed for the production of random copolymers with two different functional groups. The selective deprotection of the sulfonate esters of the copolymers proceeded smoothly and resulted in the formation of copolymers with lithium vinyl sulfonate units and cross-linkable trialkoxysilane units. The co-condensation of the trialkoxysilane moieties in the deprotected copolymers with cross-linkers yielded transparent hybrid films that contained lithium sulfonate groups without aromatic rings or ester linkages. 相似文献
5.
Oliver W. Smith Martha J. Collins Peter S. Martin David R. Bassett 《Progress in Organic Coatings》1993,22(1-4):19-25
New vinyl ester monomers are now available for the preparation of emulsion copolymers with improved hydrolytic stability and water resistance. These improved properties are the result of uniform copolymerization of hydrophobic monomers having approximately the same reactivity as vinyl acetate. Latex coatings with excellent gloss, water spot resistance, blocking and other desirable performance properties can now be obtained with vinyl acetate copolymers. 相似文献
6.
Dissociation behavior of a hydrophilic copolymer having three kinds of hydroxyl groups, ie primary OH on α‐hydroxyallyl alcohol component, hemiacetal OH on cyclic hemiacetal component and tertiary OH on α‐hydroxyacrylate component, was investigated as a function of the polymer constitution to study effects from possible intramolecular hydrogen bonds between the carboxyl group and those hydroxyl groups. The apparent dissociation constant, pKa, decreased with increasing fraction of the hemiacetal component, suggesting that the carboxyl anion is stabilized by intramolecular hydrogen bonding with the hemiacetal OH group. Furthermore, the decrease in pKa value was more significant at the lower degrees of dissociation, α. This dissociation behavior was found to be consistent with IR peak shifts to higher wavenumbers observed for the asymmetric vibration band of ? COO?, which were more significant with decreasing α and for copolymers with larger hemiacetal contents. Effects from the lactone ring, formed during titration, on the pKa values are also discussed. Copyright © 2005 Society of Chemical Industry 相似文献
7.
New thermosetting coatings using blocked carboxyl groups 总被引:1,自引:0,他引:1
Characteristics of blocked carboxylic acid compounds obtained by blocking carboxyl groups with alkyl vinyl ethers were studied, and new thermosetting coatings using blocked carboxyl groups and epoxide were also studied. Polybasic carboxylic acids were esterified with alkyl vinyl ethers to obtain blocked carboxylic acids having the hemiacetal ester moieties. Most of blocked carboxylic acids obtained were liquids and showed an excellent solubility in organic solvents and a good compatibility with epoxy resins. Although the blocked carboxylic acids were stable under ambient conditions, they could regenerate the corresponding carboxylic acids accompanied by the elimination of alkyl vinyl ethers by the thermal dissociation. They could be used as noble thermal latent hardeners. Curing of the blocked carboxyl groups and epoxide in the presence of relatively weak Lewis acid proceeded through a sequence of three-step reactions consisting of deblocking of alkyl vinyl ethers, esterification of epoxide, and the addition of alkyl vinyl ether to 2-hydroxyalkyl ester. The main product of the curing system was 2-acetalalkyl ester, but not 2-hydroxylalkyl ester. The new one-package thermosetting coatings using blocked carboxyl groups have been evaluated for use in the practical automotive and coil coatings line production. VOCs reduction, low-toxicity, and cost saving are satisfactory for the application of the systems. And the cured films of the coatings offered advantages in the high durability, the acid resistance and the soil resistance. 相似文献
8.
The influence of comonomer species and concentration on the ease of alkaline hydrolysis of vinyl acetate copolymers in the aqueous dispersion form is reported. The comonomers studied include higher vinyl esters, acrylic esters, a fumaric diester, and ethylene. The significance of the emulsion polymerization formulation has also been considered. The rate of hydrolysis is reduced with increasing proportions of comonomers and with increasing length and branching of the alkyl side chain originating from such comonomers. Branched long-chain tertiary vinyl esters reduce not only the rate but also the extent of hydrolysis, being resistant to hydrolysis themselves and also protecting part of the more susceptible vinyl acetate; inhomogeneous copolymers, specially prepared, were less resistant than the more homogeneous copolymer of the same overall composition. The inclusion of quite small amounts, such as 1% by weight, of acid comonomers has a relatively large effect, increasing ease of hydrolysis. For comparison, the behavior of higher vinyl ester homopolymers and methyl methacrylate copolymers with acrylic esters is included. It is concluded that the major factors influencing ease of hydrolysis are steric and other environmental effects arising from the copolymer microstructure. 相似文献
9.
In the present study, the effects of charge‐transfer complex formation and intramolecular fragmentation (side‐chain lactonization) in radical copolymerization of tert‐butyl vinyl ether (t‐BVE) with anhydrides of maleic (MA) and citraconic (CA) acids and the structure–thermal behavior relationships of the resulting copolymers were examined using the 1H‐NMR, FTIR, DSC, and TGA analysis methods. It was shown that copolymerization under the chosen conditions proceeded through intramolecular fragmentation with the formation of γ‐lactone units. Side‐chain fragmentation of t‐BVE–MA and t‐BVE–CA copolymers also was confirmed by TGA and DSC analysis. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2455–2463, 2006 2006 相似文献
10.
The photoinitiated copolymerization of chlorotrifluoroethylene (CTFE) with several vinyl ethers [ethyl vinyl ether (EVE), 2‐chloroethyl vinyl ether (CEVE), cyclohexyl vinyl ether (CHVE), 4‐hydroxybutyl vinyl ether (HBVE)] was studied. CTFE is an acceptor monomer (e ~ 1.5) whereas vinyl ethers are donor monomers (e ~ ?1.5), and therefore their copolymerization led to alternating copolymers, as indicated by elementary analysis. The equilibrium constant (KF) of the charge‐transfer complex formation (CTC) was determined by 19F NMR spectroscopy. Under our experimental conditions, KF was low for CHVE/CTFE and HBVE/CTFE systems, 0.058 and 0.013 l mol?1 respectively. It can be assumed that the copolymerization involves the free monomers rather than propagation via the donor–acceptor complex. The alternating structure arises from the great difference in polarity between the two types of monomers. Several functional copolymers were prepared in good yield and with molecular weight close to 15 000 g mol?1. © 2002 Society of Chemical Industry 相似文献
11.
Eight new copolymers containing hindered amine (HA) were synthesized by copolymerization of vinyl monomers [styrene (St), methyl methacrylate (MMA)] with new functional monomers produced by reaction of 4-amino-2,2,6,6-tetramethylpiperidine (ATMP) and epoxy compounds containing double bond, and mixture copolymerization of vinyl monomers (St and MMA) with a mixture of ATMP and above epoxy compounds. The structure of these new copolymers were characterized by IR, NMR, and elemental analysis. The properties of these new copolymers were described and their photoprotecting effectiveness examined. Experimental results indicate that they possess high photoprotecting effectiveness comparable to or higher than that of a commercial polymeric HALS “PDS.” © 1996 John Wiley & Sons, Inc. 相似文献
12.
Sunirmal Pal Balaraju Banoth Goli Rahithya Ashish Dhawan Priyadarsi De 《Polymer》2012,53(13):2583-2590
Copolyperoxides of 2-(acetoacetoxy)ethyl methacrylate (AEMA) with styrene (St) and methyl methacrylate (MMA) of different compositions have been synthesized in the presence of 2,2′-azobisisobutyronitrile as a free radical initiator under 100 psi oxygen pressure at 50 °C. The rates of oxidative copolymerization reactions are determined from the oxygen consumption (Δp) against time plot. Highly exothermic thermal degradations of these copolyperoxides are studied using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) and degradation products have been characterised by electron-impact mass spectroscopy (EI-MS). The NMR spectroscopy and EI-MS analysis confirm the alternating peroxy bonds in the main chain. The monomer reactivity ratios are computed by the Fineman–Ross and Kelen–Tüdös methods, using compositions obtained from 1H and 13C NMR analysis. These copolymers can potentially be used as polymeric initiators for the radical polymerization of vinyl monomers, autocombustible fuel. Also, the β-carbonyl moieties along the side chain of the copolyperoxides can be utilized to prepare degradable polyperoxide–metal complexes. 相似文献
13.
Dmitrii V Ludin Sergey D Zaitsev Alexey V Markin Ivan D Grishin Semen S Sologubov Tatyana A Kovylina Igor L Fedushkin 《Polymer International》2022,71(1):86-97
We developed a new approach to obtain polylactide hybrid block copolymers with vinyl monomers (styrene, methyl methacrylate, methyl acrylate) through the realization of a reaction sequence using triethylborane and various p-quinones. The method offered includes two stages. In the first stage, a chain-transfer agent was obtained by borylation of the terminal hydroxyl groups of polylactide. The second stage was vinyl monomer radical polymerization in the presence of p-quinone accompanied by SH2-substitution at the boron atom.1,4-Naphthoquinone, 2,3-dimethyl-1,4-benzoquinone, duroquinone and 2,5-di-tert-butyl-1,4-benzoquinone were used as synthetic polymer chain growth mediators. It is shown that 1,4-naphthoquinone and 2,3-dimethyl-1,4-benzoquinone, similar in their characteristics, are effective agents providing the realization of reversible-deactivation radical polymerization. Realization of reversible-deactivation radical polymerization was proved with the analysis of the kinetics of block copolymerization, molecular weight characteristics and compositional homogeneity of block copolymers as well as its further capability to elongate the polymer chain. Synthesized block copolymers have a high thermal stability compared to the initial borylated polylactide. © 2021 Society of Industrial Chemistry. 相似文献
14.
Samia M. Mokhtar Magdy W. Sabaa Said S. Elkholy Maher Z. Elsabee 《Journal of Polymer Research》2000,7(4):229-235
1-Cyanoethanoyl-4-acryloylthiosemicarbazide (CEATS) was synthesized for the first time as a new chelating monomer. Its structure
was confirmed by both elemental and spectral analyses. Radical polymerization and copolymerization of CEATS was been carried
out in dimethylformamide (DMF) in the presence of azobisisobutyronitrile (AIBN) as an initiator. Kinetic studies for the polymerization
behavior of CEATS were performed. The complex formation of the CEATS monomer and polymer (PCEATS) with Cu II cation was investigated
and its stability constant determined. The rate of copolymerization of CEATS with some conventional monomers, namely vinyl
acetate, methyl methacrylate and acrylonitrile, was measured as a function of the mole fraction of the monomers. The reactivity
ratios (r1, r2) for the various copolymer systems investigated together with the Q and e values of the CEATS monomer were determined. Moreover, the thermal gravimetric analysis of the prepared polymers and their
copolymers with acrylonitrile were also studied. 相似文献
15.
Four sets of copolymeric additives were synthesized via copolymerization of dialkyl fumarates and dialkyl maleates with vinyl acetate (VAc) and vinylpyrrolidone (VP) monomers. The
dialkyl esters were prepared by the esterification of maleic and fumaric acids with a series of n-alkanol having an increasing
number of carbon atoms to produce two groups of diesters. The completion of the esterification reaction was confirmed by spectroscopic
analysis. The molecular weights of the prepared esters and copolymers were determined and the influences of different parameters
on the molecular weight of the produced copolymers were discussed. The efficiency of the prepared copolymers as viscosity
index and flow improvers (pour point depressants) was investigated. It has been found that the dialkyl ester/VP copolymers
are more efficient as viscosity index improvers than the dialkyl ester/VAc copolymers. On the other hand, it has been found
that the copolymers based on didodecyl fumarate/VAc are the most effective pour point depressants. 相似文献
16.
利用端基转换法合成了不同组成及相对分子质量的端丙烯酰胺基聚(N-异丙基丙烯酰胺-co-N,N-二甲基丙烯酰胺)[poly(NIPA-co-DMAM), PID]大分子单体;与丙烯酰胺聚合后再水解,得到以PID为侧链,浊点在37~63℃的接枝共聚物[HPAM-g-P(NIPA-co-DMAM), HGPID]。利用1H NMR及端基分析等对大分子单体和接枝物的组成及结构进行了表征;考察了接枝共聚物侧链的组成和链长、共聚物质量浓度和外加盐浓度等因素对其水溶液的热敏特性及温敏增稠性的影响。 相似文献
17.
New Vinyl Ester Bio-copolymers Derived from Dimer Fatty Acids: Preparation, Characterization and Properties 总被引:1,自引:0,他引:1
Shouhai Li Jianling Xia Mei Li Kun Huang 《Journal of the American Oil Chemists' Society》2013,90(5):695-706
Two different vinyl ester resin monomers derived from dimer fatty acids (DA), dimer fatty acids polymerized glycidyl methacrylate (DA-p-GMA) resin and maleic anhydride modified dimer fatty acids polymerized glycidyl methacrylate (MA-m-DA-p-GMA) resin were prepared via simple ring-opening and esterification. FTIR, 1H-NMR and GPC results demonstrated that these two target products have been successfully synthesized. Moreover, DA-based vinyl ester resin–styrene copolymers with different weight ratios were also prepared by a thermal polymerization, and their mechanical, morphological and thermal properties were investigated. Mechanical tests displayed that the prepared copolymers had excellent mechanical properties, and even at a low styrene content of 30 wt%, the copolymers still had excellent flexural strength of 29.14 MPa and tensile strength of 15.99 MPa. Micro-morphological investigation displayed that the copolymers had glossy and smooth impact resistance fractured surfaces, indicating distinctive fast brittle fracture features. Dynamic mechanical analysis (DMA) revealed that the copolymers’ glass-transition temperatures were within a broad range from 44 to 72 °C. Thermogravimetric results demonstrated that the copolymers had excellent thermal stability, as all copolymers showed a high thermal initial decomposition temperature above 390 °C. 相似文献
18.
Solvatochromic merocyanine dyes were immobilized onto polymer surfaces and copolymerized with acrylic resins, yielding novel reversibly solvatochromic polymers, which were used as solvent polarity indicators that exhibited different colors in water and alcohols. To generate solvatochromic polymer for solvent polarity indication, two solvatochromic merocyanine dyes containing moieties, which allow their immobilization onto polymer surfaces, or copolymerization with acrylic and vinyl monomers, were sequentially synthesized in four and six steps. Merocyanine dye (E)‐2‐(2‐(1‐(6‐aminohexyl)pyridinium‐4‐yl)vinyl)‐4,6‐dichlorophenolate (AHPVD) was prepared with a terminal aminohexyl group which allowed covalent bonding to activated carboxylated or sulfonated polymeric materials. The dyes were covalently bonded to the polymer surfaces, such as, nylon, polycarbonate, polyethylene terephthalate, and silicone. Solvatochromic merocyanine dye (E)‐2‐(2‐(1‐(6‐acrylamidohexyl)pyridinium‐4‐yl)vinyl)‐4,6‐dichlorophenolate (AAPVD) was synthesized for radical copolymerization with acrylate and vinyl monomers and oligomers. Side‐chain solvatochromic merocyanine‐containing hydrophilic polymers with differential water and alcohol absorption were obtained upon photoinitiated radical copolymerization with specially formulated acrylated resins. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44451. 相似文献
19.
N-(2-Carbobenzyloxyaminoethyl)acrylamide (CAEA) which is a vinyl compound carrying a protected aliphatic primary amino group in the side chain has been synthesized and its homopolymerization and copolymerization induced by radical initiators have been investigated. CAEA was found to possess good copolymerizability with vinyl monomers having large Q values such as styrene, 2-vinyl pyridine, acrylonitrile and methyl methacrylate. Vinyl polymers containing a small amount of aliphatic primary amino group in the side chain were produced by the treatment of vinyl polymers containing a small amount of CAEA unit with HBr/AcOH or . Using the former polymers as initiators for the polymerization of N-carboxyanhydrides of (RS)-Phe and (S)-Glu(OBz), vinly polymer (trunk)-poly-(α-amino acid) (branch) graft copolymers were synthesized. These copolymers were investigated by transmission electron microscopy, and the development of domain structure due to microphase separation was observed. 相似文献
20.
Copolyperoxides of different compositions of indene with vinyl acetate and isopropenyl acetate were synthesized by the free radical‐initiated oxidative copolymerization. The compositions of copolyperoxides obtained from 1H‐ and 13C‐NMR spectra have been used to determine the reactivity ratio of the monomers. The reactivity ratios reveal that the copolyperoxides contain a larger proportion of the indene units in random placement. The NMR studies further suggest irregularities in the copolyperoxide chain possibly due to the cleavage reactions of the propagating peroxide radical. The thermal analysis by differential scanning calorimetry (DSC) supports the alternating peroxide units in the copolymer chain. The activation energy for the thermal degradation suggests that the degradation is dependent on the dissociation of the peroxide (? O? O? ) bonds in the copolyperoxide chain. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86:639–646, 2002 相似文献