Copolymerization of 2-hydroxypropyl methacrylate with alkyl acrylate monomers

2-Hydroxypropyl methacrylate has been copolymerized with methyl acrylate, ethyl acrylate, n-butyl acrylate, and methyl methacrylate in bulk at 60°C using benzoyl peroxide as initiator. The compositions of copolymers have been determined by the estimation of the hydroxyl group by acetylation process. The copolymerization parameters have been determined by conventional scheme of copolymerization.     

Copolymerization of 2-hydroxyethyl methacrylate with alkyl acrylates

Copolymerization of 2-hydroxyethyl methacrylate (HEMA) with methylacrylate (MA), ethylacrylate (EA), n-butylacrylate (BA) and methylmethacrylate (MMA) were studied in bulk at 60° using benzoyl peroxide as initiator. The monomer reactivity ratios were determined using several methods and are briefly discussed.     

Copolymerization of fluorinated acrylic monomers with p-vinylphenol and hydroxyethyl methacrylate

Copolymers of p-vinylphenol were prepared in bulk with heptafluorobutyl and pentadecafluorooctyl acrylates and trifluoroethyl, hexafluoroisopropyl, heptafluorobutyl, octafluoropentyl and pentadecafluorooctyl methacrylates using azobisisobutyronitrile as the initiator in sealed tubes. Intrinsic viscosities of the copolymers ranged from 0.44 to 1.85. Monomer reactivity ratios for copolymers of trifluoroethyl methacrylate (M₁) were: with hydroxyethyl methacrylate (M₂), r₁ = 0.47, r₂ = 1.0; with methyl methacrylate (M₂), r₁ = 0.82, r₂ = 0.50; with styrene (M₂), r₁ = 0.29, r₂, = 0.20; and with p-vinylphenol (M₂), r₁ = 0.096, r₂ = 1.5. Q and e values of trifluoroethyl methacrylate were 1.30 and 0.92, respectively. Monomer reactivity ratios of octafluoropentyl methacrylate (M₁) were: with styrene (M₂), r₁ = 0.26, r₂ = 0.20; and with p-vinylphenol, r₁ = 0.21, r₂ = 1.5. Q and e values for octafluoropentyl methacrylate were 1.27 and 0.92, respectively. Critical surface tensions of the homopolymers ranged from 17.9 to 14.8 dyn/cm. A copolymer of hexafluoro-i-propyl methacrylate and p-vinylphenol exhibited a critical surface tension of 16.5 dyn/cm.     

Atom transfer radical copolymerization of glycidyl methacrylate and allyl methacrylate, two functional monomers

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).     

Copolymerization of acrylonitrile with 3-chloro, 2-hydroxy-propyl acrylate and methacrylate

Acrylonitrile (AN) was copolymerized with 3-chloro, 2-hydroxy propyl acrylate (CHPA) and 3-chloro, 2-hydroxy-propyl methacrylate (CHPMA) in water and water-acetone medium at 40°C with potassium persulfate and sodium metabisulfite as redox initiators. Copolymer composition was determined from the nitrogen content. The reactivity ratios for the AN-CHPMA system were also calculated by the Kelen–Tudos method. The reactivity ratio r₂ (CHPMA) was higher for the AN-CHPMA system in both media, which indicated higher reactivity of CHPMA toward the propagation species. Addition of acetone decreases r₂ and increases r₁. It was found that the copolymers prepared in water medium were not completely soluble in dimethylformamide (DMF); the insoluble fraction was rich in CHPA/CHPMA and increased with increasing comonomer composition. The influence of the acrylate comonomer on properties such as solubility and intrinsic viscosity was also studied.     

Synthesis of new amphiphilic block copolymers. Block copolymer of sulfonated glycidyl methacrylate and alkyl methacrylate

Water-soluble amphiphilic block copolymers consisting of a hydrophobic block of poly(alkyl methacrylate) and a hydrophilic anionic polyelectrolyte block have been synthesized by a living anionic polymerization of methyl methacrylate and glycidyl methacrylate and subsequent selective modification of the oxirane groups of the glycidyl methacrylate block into hydroxysulfonate groups by a phase transfer catalyzed sulfonation reaction. The block copolymers were characterized by a predictable motecular weight and a narrow molecular weight distribution while the yield was quantitative. These amphiphilic block copolymers display surfaceactive behavior in water and they are characterized by a critical micelle concentration.     

Organotin polymers—II.Copolymerization parameters for tributyltin methacrylate with methyl acrylate,ethyl acrylate,butyl acrylate and acrylonitrile

Copolymerizations of tributyltin methacrylate (M₁) with methyl acrylate, ethyl acrylate, n-butyl acrylate and acrylonitrile were carried out in solution at 70° using azobisisobutyronitrile as initiator. Copolymer compositions were determined by tin analysis; monomer reactivity ratios were calculated by Fineman-Ross and Kelen-Tüdös methods. The reactivities of acrylic esters decrease as the alkyl group becomes bulkier. Azeotropic copolymers could be formed from tributyltin methacrylate with butyl acrylate and with acrylonitrile. The structures of M₁ and its azeotropic copolymers have been investigated by infrared spectroscopy.     

Copolymerization of eight-membered ring-opening allylic sulfide lactone and disulfide monomers with methyl methacrylate and styrene

Apparent reactivity ratios and detailed NMR analysis of copolymerizations of eight membered ring-opening allylic sulfide monomers; 3-methylene-1,5-oxathiocan-2-one 2 and 2,2,4-trimethyl-7-methylene-1,5-dithiocane 5 with methyl methacrylate and styrene are presented. The activated double bond of 2 and unactivated double bond and additional methyl substituents of 5 were found to have a profound affect on reactivity. The copolymerization rates were analyzed based on the lumped parameter k_p(f/k_t)^0.5, which was estimated as a function of monomer composition in the feed.     

Organotin polymers—III: Copolymerization and terpolymerization of tributyltin acrylate with methyl methacrylate,propyl methacrylate,butyl methacrylate and acrylonitrile

Copolymerizations of tri-n-butyltin acrylate (M₁) with (a) methyl methacrylate (M₂), (b) propyl methacrylate (M₃), (c) butyl methacrylate (M₄) and (d) acrylonitrile (M₅) in solution at 70 using AIBN as initiator led to monomer reactivity ratios as follows: (a) r₁ = 0.401 and r₂ = 2.199, (b) 0.323 and 1.713, (c) 0.196 and 1.65, and (d) 0.243 and 1.008. The variation of the average copolymer composition with conversion for two copolymers from M₁ with M₂ and M₄ were calculated and verified experimentally. Four terpolymer compositions involving M₁ and M₅ with M₂ or M₄ were prepared and the terpolymer compositions were calculated on the basis of tin and nitrogen analyses. The variations of instantaneous and average terpolymer composition with conversion fit satisfactorily the experimental results over a wide range of conversion.     

Copolymerization behavior of 2-vinylbenzofuran: Copolymers of ethyl acrylate,n-butyl acrylate,and methyl methacrylate

The reactivity of 2-vinylbenzofuran in copolymerization reactions with n-butyl acrylate, ethyl acrylate, and methyl methacrylate was investigated. The vinylbenzofuran was found to be a very reactive monomer with the growing chain preferring to react with this monomer no matter what its terminus. Reactivity ratios were calculated using a nonlinear least squares error-in-variables method, which gives more reliable values of r₁ and r₂.     

Self-crosslinkable polymers. I. Copolymerization of glycidyl methacrylate with 2-vinylpyridine and 2-vinyl-5-ethylpyridine

A soluble and self-crosslinkable linear copolymer with pendant epoxy and pyridyl groups was obtained from glycidyl methacrylate (M₁) and 2-vinylpyridine (M₂) or 2-vinyl-5-ethylpyridine (M₂) by the action of azobisisobutyronitrile. The monomer reactivity ratios were determined in tetrahydrofuran at 60°C: r₁ = 0.510, r₂ = 0.620 with 2-vinylpyridine and r₁ = 0.57, r₂ = 0.62 with 2-vinyl-5-ethylpyridine. These were consistent with the calculated values with the reported Q and e values for these monomers. The intrinsic viscosities of the copolymers with 2-vinylpyridine and with 2-vinyl-5-ethylpyridine were found to be 0.17–0.19 and 0.26–0.38, respectively, in tetrahydrofuran at 30°C; they were independent of the copolymer composition. The copolymers were amorphous, had no clear melting points, and became insoluble crosslinked polymers under heating without further addition of any curing agents.     

Copolymerization of N‐vinylcaprolactam and glycidyl methacrylate: Reactivity ratio and composition control

Free‐radical copolymerizations of N‐vinylcaprolactam (VCL) and glycidyl methacrylate (GMA) were investigated to synthesize temperature‐responsive reactive copolymers with minimized compositional heterogeneity. The average copolymer composition was determined by Fourier transform infrared and nuclear magnetic resonance techniques. The reactivity ratios for VCL and GMA were found to be 0.0365 ± 0.0009 and 6.44 ± 0.36 by the Fineman–Ross method and 0.039 ± 0.006 and 6.75 ± 0.29 by the Kelen–Tudos method, respectively. When prepared by batch polymerization, VCL–GMA copolymers had a highly heterogeneous composition and fractions of different solubilities in water. The use of a gradual feeding technique, which included the sequential addition of more reactive GMA monomer into the reaction, yielded copolymers with much more homogeneous composition. The produced copolymers with 0.9 and 0.11 fractional GMA contents preserved their temperature‐responsive properties and precipitated from aqueous solutions when the temperature exceeded 31 °C. The GMA units in the VCL–GMA copolymers were capable of reacting with amino end‐functionalized poly(ethylene oxide) at room temperature to produce poly(N‐vinylcaprolactam)–poly(ethylene oxide) graft copolymers. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 183–191, 2006     

Novel activated acrylates: synthesis, characterization and the reactivity ratios of 4-acetamidophenyl acrylate copolymers with methyl methacrylate and glycidyl methacrylate

A new functional activated acrylate, 4-acetamidophenyl acrylate (APA) was synthesized and characterized by IR, 1H- and 13C-NMR and mass spectra. Homo and copolymers of APA with MMA and GMA were prepared by free radical polymerization. All the copolymer compositions have been determined by 1H-NMR and the reactivity ratios of the monomer pairs have been evaluated. APA (r₁): 1.099 and MMA (r₂): 1.210 for copoly(APA-MMA) system. APA (r₁): 0.648 and GMA (r₂): 1.30 for copoly(APA-GMA) system. Thermal stability and molecular weights of the copolymers were reported.     

Polymerization of surface-active monomers. II. Polymerization of quarternary alkyl salts of dimethylaminoethyl methacrylate with a different alkyl chain length

The cationic monomers (C_NBr), obtained by quarternization of dimethylaminoethyl methacrylate with n-alkyl bromide containing varying carbon number (N = 4, 8, 12, 14, and 16) were polymerized with radical initiators in water and various organic solvents. The degree of polymerization of the resulting polymers was determined by GPC measurements on poly(methyl methacrylate) samples derived from them. The rate of polymerization of the micelle-forming monomers (N = 8, 12, 14, and 16) in water increases with increasing a chain length of alkyl group, whereas it is little dependent on N in isotropic solution in dimethylformamide. The data on the degree of polymerization for the polymers of C₄Br, C₈Br, and C₁₂Br show that the polymerization of C₁₂Br with azo initiators in water and benzene gives polymers with a very high degree of polymerization. The results obtained here suggest that highly developed or relatively rigid, aggregated structures of monomers in solution are responsible for the formation of the polymers with a very high degree of polymerization, in addition to an enhanced rate of polymerization. Also considered are the relation of the molecular weight of poly(C₁₂Br) to the viscosity data in chloroform and methanol.     

Copolymerization of fluorinated monomers with nonfluorinated monomers. Reactivity and mechanisms

The copolymerization of two monomers usually leads to random copolymers except when one of both bears an electron-acceptor group and the other one has an electron-donor group. Many copolymers are commercially available, mainly in the series of hydrogenated monomers (S.M.A., GANTREZ, MALIALIM resins). The field of fluorinated copolymers is very interesting because of the strong electron-acceptor behaviour of the fluorine atoms and more generally of halogenated atoms. Thus, after HALAR (CTFE^a)-ethylene), TEFZEL (TFE-ethylene) and AFLAS (TFE^b)-propylene) resins, a new series of resins have been produced (copolymers of CTFE and vinyl ethers commercialized by ASAHI Corp.). So it can be considered that ACCEPTOR-DONOR copolymerization with fluorinated monomers is one of the most important applications of that kind of research. After reminding the main mechanisms of that reaction (homopolymerization of charge transfer complex and copolymerization of free monomers), it will be discussed about the mechanism in some examples (CTFE-vinyl ethers and other pairs of monomers). Then it will be explained how cotelomerization has provided new data to prefer a copolymerization mechanism by free monomers.     

Polymerization of complexed monomers. II. Alternating copolymers of indene with methyl acrylate and methyl methacrylate

Indene has been copolymerized with polar monomers in the presence of ethylaluminum sesquichloride. The polymers have molecular weights in the 7,000–10,000 range and soften at temperatures above 150°C. The NMR spectra of the copolymers are discussed with reference to polymer structures and chain conformations. Indene is comparable to cyclopentene in reactivity in copolymerizations with methyl acrylate but is much more reactive than cyclopentene toward methyl methacrylate.