Copolymerization of allyl esters of some fatty acids

Attempts have been made unsuccessfully to homopolymerize a number of allyl esters of substituted fatty acids by radical initiation in emulsion systems. Copolymerizations of these allyl esters with styrene, methyl methacrylate, and vinyl chloride have been investigated. Of these comonomers, styrene and methyl methacrylate do not copolymerize well with the allyl esters, whereas vinyl chloride does. Reactivity ratios for the radical copolymerization of allyl 11-iodoundecanoate, M₁, and vinyl chloride, M₂, determined at 60°C. in benzene, are r₁ = 0.42 and r₂ = 1.64. A copolymer of allyl 10, 11-dibromoundecanoate and vinyl chloride was fractionated and found to be fairly homogeneous.     

Application of the monomer reactivity ratios to the kinetic‐model discrimination and the solvent‐effect determination for the styrene/acrylonitrile monomer system

The impact of reactivity ratios determined with the Nelder and Mead simplex method on the kinetic‐model discrimination and the solvent‐effect determination for the styrene/acrylonitrile monomer system was investigated. For the monomer system, the penultimate unit effect was inversely proportional to the polarity of the solvent: acetonitrile < N,N‐dimethylformamide < methyl ethyl ketone < toluene. Quantitatively, the penultimate unit effect could be correlated with an absolute value of the difference between the standard deviation of the reactivity ratios determined for the terminal and penultimate models. By application of the F test, the penultimate model was justified for copolymerization in toluene. The conclusion was less certain for polymerization in methyl ethyl ketone. With a scanning procedure based on the simplex method, it was found that an equivalent representation of the copolymer‐composition data could be achieved with multiple sets of penultimate‐model reactivity ratios. However, the relationship between the triad‐sequence distribution and copolymer composition depended on the reactivity‐ratio set chosen for the microstructure determination. The microstructure calculated with the penultimate‐model reactivity ratios determined with the simplex method from the initial guess (r₁₁ = r₁, r₂₁ = 1/r₂, r₂₂ = r₂, r₁₂ = 1/r₁) did not obey the general “bootstrap effect” rule. This observation still requires some theoretical interpretation. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 846–854, 2000     

Aminobutadienes. VI. Polymerization and Copolymerization of 2-Phthalimido-1,3-butadiene

2-Phthalimido-1,3-butadiene (2-PB) was polymerized either radically or thermally in bulk and in solution. While the polymer obtained by solution polymerization was soluble in some solvents such as halogenated hydrocarbons, dioxane, and dimethylformamide and had a softening point in the range of 160–170°C., that obtained by polymerization in bulk was insoluble in any solvent and only swollen on being immersed in such solvents as above. The reduced viscosity of the soluble polymer obtained by solution polymerization was approximately 1.0, and this value remained almost unchanged with varying polymerization time. Likewise the cationic polymerization in acetylene tetrachloride or in chloroform at 20°C. with the use of cationic catalysts such as boron trifluoride and stannic chloride was attempted, but no formation of polymer was observed. This monomer preferentially reacted with acrylonitrile, methyl methacrylate, styrene, and N-vinylphthalimide to form the respective copolymers; it reacted somewhat less readily with vinyl acetate. The monomer reactivity ratios in the copolymerization with styrene were calculated by the Fineman and Ross method and found to be r₁ (2-PB) = 5.2 and r₂ (styrene) = 0.11, respectively, from which the Q, e parameters were successively evaluated to be Q = 5.0 and e = ?0.05. The fact that e value is close to zero, easily explains why this monomer can copolymerize well both with acrylonitrile, which has a highly positive value of e (1.2) and with styrene, for which e is considerably negative (-0.8).     

Organometallic Polymers. XXVII. Radical-Initiated Polymerization and Copolymerization of π-(2, 4-Hexadien-1-yl Acrylate) tricarbonyliron

The novel monomer, π-(2, 4-hexadiene- l-yl acrylate) tricarbonyliron (HATI), has been prepared by two routes. It was homopolymerized and copolymerized with acrylonitrile, vinyl acetate, styrene, and methyl acrylate in benzene solutions. In all cases azobisisobutyronitrile was the initiator. The relative reactivity ratios, where HATI is defined as M₁, were determined: r₁ = 0.34, r₂ = 0.74, M₂ = acrylonitrile; r₁ = 2.0, r₂ = 0.05, M₂ = 0.74, M₂ = acrylonitrile; r₁ = 2.0, r₂ = 0.05, M₂ = vinyl acetate; r₁ = 0.26, r₂ = 1.81, M₂ = styrene; and r₁ = 0.30, r₂ = 0.74, M₂ = methyl acrylate. The homo-and copolymers had high values of T_g. When polymerizations are carried out at high concentrations, a very high molecular weight tail is observed in HATI hompolymerizations and in HATI-methyl acrylate copolymerizations. The polymers were characterized by IR, gel permeation chromatography, viscosity, and differential scanning calorimetry studies. Finally, thermal decompositions carried out in air resulted in decomposition of the Fe(CO)₃ group, producing Fe₂O₃ as a fine powder. Thermal decomposition under nitrogen (in solution and on solids ground into KBr pellets) resulted in slow destruction of the Fe(CO)₃ groups but the resulting polymer mass was insoluble, and the question of what form the iron exists in (Fe metal, oxides, carbides, etc.) has not been answered.     

Emulsion polymerization and copolymerization of vinyl benzoate

Emulsion polymerization of vinyl benzoate and its copolymerization with vinyl acetate or styrene are described. The effect of the potassium persulfate initiator, and the sodium lauryl sulfate emulsifier concentration on the rate of vinyl benzote homopolymerization and the molecular weight of the polymers was determined. In copolymerization with vinyl benzoate, both comonomers, vinyl acetate and styrene, decrease the initial polymerization rate. With increasing amounts of styrene in the comonomer mixture the polymerization rate increases but with vinyl acetate an opposite effect is observed. Reactivity ratios of copolymerizations were determined. For the vinyl benzoate [M₁]-styrene [M₂] comonomer system a r₁ = 0.03 and a r₂ = 29.58 and for vinyl benzoate [M₁]-vinyl acetate [M₂], a r₁ = 1.93 and a r₂ = 0.20 was obtained. From the vinyl benzoate-styrene reactivity ratios the Qe parameters were calculated.     

Photopolymerization of β-Allyloxypropionaldehyde

Homo- and copolymerizations of β-allyloxypropionaldehyde (I) have been carried out by photoirradiation at 12–13°C in degassed glass ampules. The number-average molecular weights of the homopolymers of I obtained in a few reaction conditions were determined by means of gel-permeation chromatography. I initiated and/or accelerated the photopolymerizations of such vinyl monomers as methyl methacrylate and vinyl acetate. Photocopolymerizabilities of I with styrene (St) and acrylonitrile (AN) were also investigated, and the copolymerization parameters were obtained as follows: for the St-I system, r₁ = 12, r₂ = 0.01; for the AN-I system, r₁ = 5.2, r₂ = 0.01.     

Free-radical homopolymerization and copolymerization of vinylferrocene

The benzene solution homopolymerization of vinylferrocene, initiated by azobisisobutyronitrile, gave a series of benzene-soluble homopolymers. Thus, free-radical copolymerization studies were performed with styrene, methyl acrylate, methyl methacrylate, acrylonitrile, vinyl acetate, and isoprene in benzene. With the exception of vinyl acetate and isoprene, which did not give copolymers with vinylferrocene under these conditions, smooth production of copolymers occurred. The relative reactivity ratios, r₁ and r₂, were obtained for vinylferrocene–styrene copolymerizations by using the curve-fitting method for the differential form of the copolymer equation, by the Fineman-Ross technique, and by computer fitting of the integrated form of the copolymer equations applied to higher conversion copolymerizations. In styrene (M₂) copolymerizations, the curve-fitting and Fineman-Ross methods both gave r₁ = 0.08, r₂ = 2.50, while the integration method gave r₁ = 0.097, r₂ = 2.91. Application of the integration method to methyl acrylate and methyl methacrylate (M₂) gave values of r₁ = 0.82, r₂ = 0.63; r₁ = 0.52, r₂ = 1.22, respectively. The curve-fitting method gave r₁ = 0.15, r₂ = 0.16 for acrylonitrile (M₂) copolymerizations. From styrene copolymerizations, vinylferrocene exhibited values of Q = 0.145 and e = 0.47.     

Miscibility of poly(vinyl chloride) with styrene/acrylonitrile copolymers

Poly(vinyl chloride) (PVC) is shown to be miscible with styrene/acrylonitrile copolymers (SAN) having AN compositions from 11.5 to 26%. Blend samples were prepared using several methods, including solution casting, melt mixing, and precipitation of solutions by a nonsolvent. It is shown that the blend phase behavior is affected by preparation method due to the solvent effect, or Δ_χ effect, and lower critical solution temperature (LCST) behavior. The intramolecular repulsion between styrene and acrylonitrile units in SAN is shown to be the cause of miscibility using heats of mixing obtained from low-molecular-weight analog compounds. An FTIR analysis supplements the above results.     

Aminimides. IV. Homo- and copolymerization studies on trimethylamine methacrylimide

Trimethylamine methacrylimide (TAMI) has been homo- and copolymerized with methyl methacrylate, vinyl acetate, vinyl chloride, hydroxypropyl methacrylate, and acrylonitrile by free-radical initiators to soluble, low molecular weight polymers containing pendant aminimide groups along the backbone of the polymer chains. The reactivity ratios in the copolymerization of TAMI (M₁) with acrylonitrile (M₂) were determined: r₁ = 0.10 ± 0.01, r₂ = 0.37 ± 0.04. The Alfrey-Price Q and e values for TAMI were also calculated: Q = 0.18, e = ?0.60. This preliminary work indicates that TAMI has potential for the preparation of reactive polymers.     

Copolymerization Parameters of Itaconic Anhydride in Free-Radical Polymerization

The copolymerization of itaconic anhydride (M₁) with four different monomers (M₂), namely: vinyl acetate, 2-chloro-ethyl acrylate, acrylonitrile, and styrene, was studied. Values of r₁ and r₂ were determined for copolymerizations in benzene and for two of these systems, namely those with vinyl acetate and 2-chloroethyl acrylate. Values of r₁ and r₂ were also determined for copolymerizations in tetra-hydrofuran. The value of ri ranged from 0.53 to 4.8, but it was always very much greater than r2. The Q-e values for itaconic anhydride in all the systems studied were also calculated and the average values for Q₁ = 8.2, e₁ = 1.45 were determined.     

Remote Unit Effects in the Copolymerization of Unconjugated Monomers

The kinetics of the radical copolymerization of the three binary systems vinyl chloride (C)-vinyl acetate (Ac), vinylidene chloride (V)-vinyl acetate, and vinyl chloride-vinylidene chloride have been investigated in the whole range of monomer feed composition using the chromatographic method. Penultimate or antepenultimate effects have been observed in all cases. The better values of the corresponding reactivity ratios are: For C-Ac copolymers, r_Ac = 0.29, r_CCC = 1.67, r_AcCC. = 4.60, and r_AcC = 2.05. For V-Ac copolymers, r_Ac = 0.07, r_VVV = 5.30, r_AcVV = 11.5, r_AcAcV = 8.0, and r_VAcV = 6.0. For C-V copolymers, r_VAcV = 0.22, r_VV = 2.94, and r_CV = 4.31. An internal transfer mechanism is suggested for the antepenultimate effect in the vinyl acetate copolymers.     

Search for a Steric Penultimate Effect: Copolymerization of 2,3,4-Trimethyl-3-pentyl Methacrylate with Styrene

The hindered monomer, 2,3,4-trimethyl-3-pentyl methacrylate (I), was synthesized for penultimate effect studies. Since it readily homopoiymerized (km¹¹¹≠ 0) and readily copolymerized with styrene, copolymerizations of I with styrene were carried out at 60°C in benzene with AIBN as initiator. The conversion to copolymer and the copolymer composition were determined by using GLC techniques. Composition-conversion data was analyzed by performing a computerized nonlinear least-squares fitting to the integrated form of the penultimate model equation. The experimental design included the use of optimized M¹°/M²° ratios. The penultimate reactivity ratios calculated from these data were r¹′ = 0.23, r¹′= 0.59, r² = 0.59, r²′ = 1.34. Thus, when I is the penultimate unit, a terminal styryl radical prefers to add styrene, whereas when styrene is the penultimate unit, terminal styryl radicals prefer to add I. These results constitute the best evidence for a steric penultimate effect yet available in the literature from composition-conversion studies. However, the case is not yet proved. Further studies to strengthen this conclusion are proposed.     

Polymerization of vinyl monomers with salts of bronsted acids

The polymerization of vinyl monomers (N-phenylmaleimide, acrylamide, acrylonitrile, methyl vinyl ketone, methyl methacrylate, vinyl chloride, and styrene) with sodium salts of Brønsted acids (sodium cyanide, sodium nitrite, sodium hydroxide, etc.) were investigated at 0°C in dimethylformamide. N-Phenylmaleimide, acrylonitrile, and methyl vinyl ketone were found to undergo polymerization with sodium cyanide, however the other monomers were not polymerized with this salt. In the polymerizations of acrylonitrile and N-phenylmaleimide with sodium cyanide, the rates of the polymerizations were found to be proportinal to the initiator concentration and to the square of the monomer concentration. The activation energy of acrylonitrile polymerization was 3.7 kcal/mole, and that of N-phenylmaleimide ws 3.0 kcal/mole. The results of the copolymerization of acrylonitrile with methyl methacrylate at 0°C in dimethyl-formamide with sodium cyanide confirm that these polymerizations proceeded by an anionic mechanism initiated by the Michael addition reaction of the monomers with the salts. In these polymerizations, the monomer reactivity increased with increase in the e values. The initiation ability of sodium salts increased with increasing pK_a of the conjugate acids and with decreasing electronegativity of metal ion in the series of lithium, sodium, and potassium cyanide. The polymerizations took place only in aprotic polar solvents, and did not occur in weak polar solvents and in protonic solvents.     

Monomer Reactivity Ratios for the Copolymerization of p-lsopropylstyrene with Styrene and Methyl Methacrylate

Abstract

The monomer reactivity ratios for the copolymerizations of p-isopropylstyrene with styrene and with methyl methacrylate have been determined by the ionization chamber-vibrating reed electrometer radioactivity assay technique. The values from the differential form of the copolymerization equation are r₁ (styrene) = 1.22, r₂ (p-isopropylstyrene) = 0.89, and r₁ (methyl methacrylate) = 0.44, r₂ (p-isopropylstyrene) = 0.39. The values from the integrated form of the equation are r₁ (styrene) = 1.37 and r₂ = 0.99. These values indicate that, in the copolymerization of p-divinylbenzene (p-DVB) with styrene, the p-isopropylstyrene-like unit, formed from having the first vinyl group of p-DVB reacted, takes part in subsequent propagation reactions with styrene less readily than either styrene or p-DVB.     

Synthesis and reactivity ratios of regioisomeric vinyl‐1,2,3‐triazoles with styrene

The free radical reactivity ratios between styrene and different vinyl‐1,2,3‐triazole regioisomeric monomers in 1,4‐dioxane at 65 °C have been established using nonlinear least square method. The results obtained for the reactivity ratio between regioisomers show exceptionally different polymerization behavior, highlighting the effects of the electronic and steric factors of these regioisomeric monomers. The experimental results highlight the effects of the electronic and sterics on the copolymerization behavior. In case of 1,4‐vinyl‐triazoles, it was found that without the steric effects, the reactivity is very similar to that of styrene and forms random copolymers. However, it was found that 1,5‐vinyl‐triazoles are more reactive than 1,4‐vinyl triazoles. In the case of styrene‐co‐1,4‐vinyl‐1,2,3‐triazoles, the reactivity ratios were calculated to be r_styrene: r_{1‐octyl‐4‐vinyl‐triazole} = 1.97:0.54, r_styrene : r_{1‐benzyl‐4‐vinyl‐triazole} = 1.62:0.50, and r_styrene: r_{1‐methyl‐4‐vinyl‐triazole} = 0.90:0.87. On the other hand, reactivity ratios for styrene‐co‐1,5‐vinyl‐1,2,3‐triazoles were found to be r_styrene: r_{1‐octyl‐5‐vinyl‐triazole} = 0.13:0.66 and r_styrene: r_{1‐benzyl‐5‐vinyl‐triazole} = 0.34:0.49. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 3359–3364     

Solvent and kinetic penultimate unit effects in the copolymerization of acrylonitrile with itaconic acid

Copolymerization of acrylonitrile (AN) with itaconic acid (IA) in dimethylformamide (DMF) and DMF/water mixture was investigated at enhanced concentrations of the latter. Analysis of the copolymer composition revealed the existence of a marked penultimate unit effect with respect to radicals terminated in AN. The reactivity of IA was considerably less than that of AN, manifested as a negative reactivity ratio for the former. The r_IA values ranging from −0.28 to −0.50 and r_AN values ranging from 0.53 to 0.70, were obtained by Kelen-Tudo's (KT) and extended KT methods. The penultimate reactivity ratios were determined by both linear and non-linear methods. The values ranged from r₁=0.009 to 0.01, r₁^′=0.0015 to 0.0043, r₂=0.54 to 0.69 and r₂^′=0.9 to 1.03. The reactivity of AN radical towards IA decreased about twofold when the latter formed the penultimate group. The penultimate model explained an acceptable rational feed-copolymer composition profile for the whole composition range. Addition of water decreased the reactivity of IA slightly. IA caused a decrease in the apparent copolymerization rate in agreement with the observed trends in the reactivity ratios; presence of water caused a further decrease in the rate of polymerization. A statistical prediction of monomer sequences based on reactivity ratios implied that IA existed as a lone monomer unit between the long sequences of AN units.     

Copolymerization characteristics of S-vinyl-O-tert-butylthiocarbonate

Poly-S-vinyl-O-tert-butylthiocarbonate is an excellent precursor to poly(vinyl mercaptan) because the tert-butyloxycarbonyl blocking group can be removed by either acid hydrolysis or thermolysis under conditions which minimize the oxidation of the liberated mercaptan to disulfide. Dilatometric studies of the homopolymerization of S-vinyl-O-tert-butylthiocarbonate demonstrated that the polymerization rate was directly proportional to the concentration of free-radical initiator; no thermal initiation was observed. The molecular weight of the homopolymers and copolymers ranged from 30,000 to 50,000 (GPC). Copolymerization of S-vinyl-O-tert-butylthiocarbonate (M₂) with styrene, (r₁ = 3.0, r₂ = 0.2), methyl methacrylate (r₁ = 1.40, r₂ = 0.17) and vinyl acetate (r₁ = 0.04, r₂ = 11.0) indicated that a sulfur atom adjacent to the vinyl group increases the resonance stability (Q₂ = 0.5) and the electron density (e₂ = ?1.4) of the double bond and the corresponding radical. Water-soluble copolymers could be prépared by incorporating either N-vinylpyrrolidone (r₁ = 0.12, r₂ = 3.94) or N-isopropylacrylamide (r₁ = 1.17, r₂ = 0.3) with M₂. The water solubility of the copolymers decreased markedly when the tert-butyloxycarbonyl group was removed. Copolymers of M₂ with N-vinyl-O-tert-butylcarbamate (r₁ = 0.13, r₂ = 5.10) were utilized to prepare crosslinked poly(vinyl amine–vinyl mercaptan); the crosslinking resulted from urea linkages formed during thermolysis of the copolymer.     

Metal‐catalyzed living radical graft copolymerization of olefins initiated from the structural defects of poly(vinyl chloride)

Commercial poly(vinyl chloride) (PVC) contains allyl chloride and tertiary chloride groups as structural defects. This article reports the use of the active chloride groups from the structural defects of PVC as initiators for the metal‐catalyzed living radical graft copolymerization of PVC. The following monomers were investigated in graft copolymerization experiments: methyl methacrylate, butyl methacrylate, tert‐butyl methacrylate, butyl acrylate, methacrylonitrile, acrylonitrile, styrene, 4‐chloro‐styrene, 4‐methyl‐styrene, and isobornylmethacrylate. Cu(0)/bpy, CuCl/bpy, CuBr/bpy, Cu₂O/bpy, Cu₂S/bpy, and Cu₂Se/bpy (where bpy = 2,2′‐bipyridine) were used as catalysts. Living radical polymerizations initiated from 1‐chloro‐3‐methyl‐2‐butene, allyl bromide, and 1,4‐dichloro‐2‐butene as models for the allyl chloride structural defects and from 3‐chloro‐3‐methyl‐pentane and 1,3‐dichloro‐3‐methylbutane as models for the tertiary chloride defects were studied. Graft copolymerization experiments were accessible in solution, in a swollen state, and in bulk. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 1120–1135, 2001     

Effect of amines on vinyl polymerization initiated by chromous acetate–alkyl halide systems

The radical polymerization of vinyl monomers initiated by Cr²⁺–RX in the presence of various amines was studied in DMF at 30°C. Polyamines able to form the chelate complex with Cr²⁺ accelerated the rate of polymerization of styrene in the following order: ethanolamine > triethylenetetramine > diethylenetriamine > ethylenediamine. However, aliphatic monoamine, hexamethylenediamine, and aromatic diamine did not have any effect on the polymerization. These results suggest that the effect of multidentate ligands may be associated with chelating effects which affect the electron transfer ability of the metal complex. An apparent activation energy of 8.2 kcal/mole for the polymerization of styrene was obtained in the presence of ethanolamine. With the Cr²⁺–CHCl₃ system, on addition of ethanolamine, the polymerization of methyl methacrylate was accelerated, and acrylonitrile and vinyl chloride, could be polymerized.