Aminimides. V. Preparation and polymerization studies of trimethylamine-4-vinylbenzimide

Trimethylamine-4-vinylbenzimide (TAVBI) has been homo- and copolymerized with styrene, methyl methacrylate, and hydroxypropyl methacrylate by free-radical initiators to soluble, low molecular weight polymers containing pendant aminimide groups along the backbone of the polymer molecules. The reactivity ratios in the copolymerization of TAVBI (M₁) with styrene (M₂) were determined: r₁ = 0.63 ± 0.07, r₂ = 0.47 ± 0.05. The Alfrey-Price Q and e values for TAVBI were also calculated: Q = 0.88, e = 0.31. This introductory work indicates that TAVBI has potential for the preparation of a wide variety of reactive polymers.     

Ferrocene-containing polymers. II. Radiation-induced copolymerizations of ferrocenylmethyl methacrylate with styrene,methyl methacrylate,and ethyl acrylate

Ferrocenylmethyl methacrylate (FMMA) was copolymerized with styrene (St), methyl methacrylate (MMA), and ethyl acrylate (EA) in benzene solution at 25°C by γ radiation. The reactions proceeded by a free radical mechanism, and monomer reactivity ratios were derived by the Tidwell–Mortimer method for St(M₁)–FMMA(M₂), r₁ = 0.35 and r₂ = 0.46; for MMA(M₁–FMMA)(M₂), r₁ = 0.85 and r₂ = 1.36; for EA(M₁)–FMMA(M₂), r₁ = 0.36 and r₂ = 3.03. The Q and e values of FMMA determined from copolymerization with St were 0.97 and 0.55, respectively. Terpolymerization of a MMA–FMMA–EA system based on the Alfrey–Goldfinger equations was studied. This is a typical terpolymerization system in which reactivities of the monomers obey the Q–e scheme. Comparing the results obtained here with those previously reported for other monomers, we concluded that FMMA is one of the most highly reactive monomers among alkyl methacrylates.     

Polymers containing fluorinated ketone groups. III. Synthesis of styrene/p-vinyltrifluoroacetophenone copolymers by modification of polystyrene and the copolymerization of monomers

Copolymers of styrene/p-vinyltrifluoroacetophenone were prepared by two different reaction routes: (1) modification of polystyrene with trifluoroacetyl chloride and (2) copolymerization of styrene and p-vinyltrifluoroacetophenone (VTFA). There appears to be a limit to the modification method because only a maximum content of 14.5 mole % trifluoroacetyl functionality could be attached to the polymer before the onset of crosslinking. Differential scanning calorimetry (DSC) was used to determine their T_g's. In addition, the reactivity ratios of styrene and VTFA were investigated. The reactivity ratios and Q and e values were r₁ = 0.30 ± 0.09 (styrene) and r₂ = 1.3 ± 0.3 (VTFA); Q₁ = 1.0 and e₁ = ?0.8 (styrene); Q₂ = 0.44 and e₂ = 1.93 (VTFA).     

Copolymerization of trialkylvinylgermane

The polymerization of trimethylvinylgermane (TMGeV) with the use of γ-ray, radical, and ionic initiator was attempted, but homopolymer was not obtained. This monomer did not undergo polymerization by itself, but polymerized with high concentration of n-BuLi. Copolymerization of TMGeV with styrene (St) and methyl methacrylate (MMA) was carried out by using radical initiator. From the results obtained by the copolymerization, monomer reactivity ratios and Q–e values were obtained as follows: for the system St(M₁)–TMGeV (M₂), r₁ = 24.4, r₂ = 0.009, Q₂, = 0.0049, e₂ = 0.43; for the system MMA (M₁)–TMGeV (M₂), r₁ = 19.98, r₂ = 0.05; Q₂ = 0.037, e₂ = 0.43., The polymerizability of TMGeV is discussed on the basis of the Q and e values obtained.     

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 of trialkylvinyltin compounds

The polymerizations of trimethylvinyltin (TMSnV) and tributylvinyltin (TBSnV) were carried out with the use of γ-ray, radical, or ionic initiators. These monomers did not undergo the polymerization by themselves, but they did copolymerize with styrene (St) or methyl methacrylate (MMA) when a radical initiator was used. From the results obtained by the copolymerization, monomer reactivity ratios and Q–e values were obtained as follows: for the system St(M₁)? TMSnV, r₁ = 44.8, r₂ = 0.001, Q₂ = 0.005, e₂ = 0.962; for the system MMA (M₁)? TMSnV, r₁ = 25.1, r₂ = 0.03, Q₂ = 0.036, e₂ = 0.933; for the system St(M₁)? TBSnV, r₁ = 16.0, r₂ = 0.005, Q₂ = 0.017, e₂ = 0.822; for the system MMA(M₁)? TBSnV, r₁ = 27.9, r₂ = 0.03, Q₂ = 0.031, e₂ = 0.822. The abilities of TMSnV and TBSnV to polymerize are discussed on the basis of the Q and e values obtained.     

Reactivity ratios for copolymerization of vinyl chloride with 2-methylpentyl vinyl brassylate by computerized linearization

A computerized version of the Fineman-Ross linearization procedure was used to determine reactivity ratios for copolymerization of vinyl chloride (monomer 1) and 2-methylpentyl vinyl brassylate (monomer 2). From differential refractometry data for the products of low-conversion copolymerization, the procedure gave r₁ = 1.06 and r₂ = 0.234. The ratios computed from chlorine contents of the same products were r₁ = 1.10 and r₂ = 0.239. The polarity factor (e₂) and general monomer reactivity (Q₂) calculated for monomer 2 from these ratios were, respectively, ?0.95 to ?0.98 and 0.032–0.033. The interquartile range for the copolymerization of a mixture of 60% monomer 1 and 40% monomer 2 was 1.4%. These values suggest that from suitable proportions of reactants, sufficiently homogeneous distribution of monomers can be achieved in copolymers of vinyl chloride and 2-methylpentyl vinyl brassylate to offer the possibility of effective internal plasticization.     

Silyl enol ethers as monomer. III. Radical polymerization and copolymerizations of 2-trimethylsilyloxy-1,3-butadiene and desilylation of the resulting polymers

2-Trimethylsilyloxy-1,3-butadiene (TMSBD), the silyl enol ether of methyl vinyl ketone, was homopolymerized with a radical initiator to afford polymers with a molecular weight of ca. 10⁴. Radical copolymerizations of TMSBD with styrene (ST) and acrylonitrile (AN) in bulk or dioxane at 60°C gave the following monomer reactivity ratios: r₁ = 0.64 and r₂ = 1.20 for the ST (M₁)–TMSBD (M₂) system and r₁ = 0.036 and r₂ = 0.065 for the AN (M₁)–TMSBD (M₂) system. The Q and e values of TMSBD determined from the reactivity ratios for the former copolymerization system were 2.34 and ?1.31, respectively. The resulting polymer and copolymers were readily desilylated with hydrochloric acid or tetrabutylammonium fluoride as catalyst to yield analogous polymers having carbonyl groups in the polymer chains.     

Synthesis and polymerization of various vinyl-type monomers containing the pyrrole ring

Vinyl-type monomers containing the pyrrole ring, such as 2-vinylpyrrole (2-VPyrr), N-(pyrrol-2-yl)methylacrylamide (PMA), N-methyl, N-(pyrrol-2-yl)methylacrylamide (MPMA), 2-allylpyrrole (2-AP), β-(pyrrol-1-yl)ethyl vinyl ether (PEVE), 2-diallyl-aminomethylpyrrole (DAMP), and 3-(2-pyrrolylmethyleneimino)propene-1 (PIP) were synthesized by various reactions involving characteristic properties of the pyrrole ring. Radical homopolymerizations and copolymerizations of these monomers were studied. In the homopolymerization of conjugated monomers such as 2-VPyrr and PMA, chain transfer to the pyrrole-containing monomer was remarkable but not degradative. The copolymerization parameters, that is, the values of r₁, r₂, Q₁, and e₁ of 2-VPyrr, were determined to be 0.066, 0.69, 5.53, and ?1.36, respectively in the copolymerization of 2-VPyrr (M₁) with MMA (M₂). The Q and e values of the monomers containing a heteroaromatic ring such as 2-vinylpyrrole, 2-vinylfuran, and 2-vinylthiophene were evaluated by the molecular orbital theory. The e value of PMA was found to be negative (?0.64) in the copolymerization with styrene, although e for acrylamide derivatives is generally positive. This may be explained by the intermolecular hydrogen bonding between the carbonyl group and NH group of PMA. That is, attraction or polarization of π-electrons in the vinyl group of PMA is weakened by such hydrogen bonding. From the results of copolymerization of 2-AP with various comonomers, the comonomers could be classified into three categories: class a monomers, in which both Q and e values are largely positive, can copolymerize with 2-AP; class b monomers, having small e values, homopolymerize and can not copolymerize with 2-AP; class c monomers, in which both Q and e values are small. The Q and e values of the comonomer must be largely positive in order to permit copolymerization with an allyl-type monomer.     

Radical copolymerization of crotonyl compounds with styrene

The monomer reactivity ratios for the radical copolymerization of crotononitrile (CN), methyl crotonate (MC), and n-propenyl methyl ketone (PMK) with styrene (St) were measured at 60°C. in benzene and little penultimate unit effect was shown for these systems. The values obtained were: St–CN, r₁ = 24.0, r₂ = 0; St–MC, r₁ = 26.0, r₂ = 0.01; St–PMK, r₁ = 13.7, r₂ = 0.01. The rate of copolymerization and the viscosity of the copolymer decreased markedly as the molar fraction of the crotonyl compound in the monomer mixture increased. The Q–e values were also calculated to be as follows: CN, e = 1.13, Q = 0.009; MC, e = 0.36, Q = 0.015; PMK, e = 0.61, Q = 0.024. A linear relationship was obtained between the e values of the crotonyl compounds and their Hammett constants σ_m.     

Aminobutadienes. X. Polymerization and copolymerization of 2-phthalimidomethyl-1,3-butadiene

The polymerization and copolymerization of 2-phthalimidomethyl-1,3-butadiene were investigated. This monomer was easily polymerized by benzoyl peroxide catalyst in bulk or in solvent, and by γ-radiation in the solid state to give polymers having a softening point of 135–145°C. Although these resulting polymers did not give x-ray diffraction patterns, they showed crystalline patterns by electron diffraction. On the other hand, cationic polymerization with the use of boron trifluoride diethyl etherate in chloroform was attempted, but no formation of the polymer was observed. Also, this monomer was easily copolymerized with styrene in N,N-dimethylformamide. The monomer reactivity ratios and Alfrey-Price Q and e values calculated from the copolymerization data of this monomer (M₁) with styrene (M₂) were r₁ = 2.0 ± 0.13, r₂ = 0.15 ± 0.02, and Q₁ = 2.78, e₁ = 0.30.     

Sulfur-Containing Vinyl Monomers. XIV. Radical Polymerizations and Copolymerizations of Vinyl Mercaptobenzazoles

Vinyl mercaptobenzazoles [thiazole (VMBT), oxazole (VMBO), and imidazole (VMBI)] were prepared through dehydrochlorination of the respective β-chloroethyl mercaptobenzazoles. These monomers were found to undergo vinyl polymerization in the presence of light or radical initiator, α,α'-azobisisobutyonitrile, to give relatively high molecular weight homopolymers. From the results of radical copolymerizations of these monomers with various monomers, the copolymerization parameters were determined as follows: VMBT(M₂): r₁ styrene(M₁): r₁ = 2.12 ± 0.09, r₂ = 0.336 ± 0.028, Q₂ = 0.75, e_z = ?1.38; VMBO(M₂)-styrene(M₁): r₁ = 2.61 ± 0.13, r₂ = 0.274 ± 0.03, Q₂ = 0.61, e₂ = ?1.38; VBMI(M₂)-styrene(M₁) r₁ =4.0, r₂ = 0.2, Q₂ = 0.37, e₂ = ?1.17. The polymerization reactivities of these monomers obtained from these parameters were compared with those of other vinyl sulfide monomers and discussed.     

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).     

Hydrophilic and hydrophobic copolymer systems based on acrylic derivatives of pyrrolidone and pyrrolidine

This article deals with the synthesis of hydrophilic methacrylic monomers derived from ethyl pyrrolidone [2‐ethyl‐(2‐pyrrolidone) methacrylate (EPM)] and ethyl pyrrolidine [2‐ethyl‐(2‐pyrrolidine) methacrylate (EPyM)] and their respective homopolymers. For the determination of their reactivity in radical copolymerization reactions, both monomers were copolymerized with methyl methacrylate (MMA), the reactivity ratios being calculated by the application of linear and nonlinear mathematical methods. EPM and MMA had ratios of r_EPM = 1.11 and r_MMA = 0.76, and this indicated that EPM with MMA had a higher reactivity in radical copolymerization processes than vinyl pyrrolidone (VP; r_VP = 0.005 and r_MMA = 4.7). EPyM and MMA had reactivity ratios of r_EPyM = 1.31 and r_MMA = 0.92, and this implied, as for the EPM–MMA copolymers, a tendency to form random or Bernoullian copolymers. The glass‐transition temperatures of the prepared copolymers were determined by differential scanning calorimetry (DSC) and were found to adjust to the Fox equation. Total‐conversion copolymers were prepared, and their behavior in aqueous media was found to be dependent on the copolymer composition. The swelling kinetics of the copolymers followed water transport mechanism case II, which is the most desirable kinetic behavior for a swelling controlled‐release material. Finally, the different states of water in the hydrogels—nonfreezing water, freezing bound water, and unbound freezing water—were determined by DSC and found to be dependent on the hydrophilic and hydrophobic units of the copolymers. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 395–407, 2003     

Copolymerization of 4-cyclopentene-1,3-dione with p-chlorostyrene and vinylidene chloride

The copolymerization of 4-cyclopentene-1,3-dione (M₂) with p-chlorostyrene and vinylidene chloride is reported. The copolymers were prepared in sealed tubes under nitrogen with azobisisobutyronitrile initiator. Infrared absorption bands at 1580 cm.^?1 revealed the presence of a highly enolic β-diketone and indicated that copolymerization had occurred. The copolymer compositions were determined from the chlorine analyses and the reactivity ratios were evaluated. The copolymerization with p-chlorostyrene (M₁) was highly alternating and provided the reactivity ratios r₁ = 0.32 ± 0.06, r₂ = 0.02 ± 0.01. Copolymerization with vinylidene chloride (M₁) afforded the reactivity ratios r₁ = 2.4 ± 0.6, r₂ = 0.15 ± 0.05. The Q and e values for the dione (Q = 0.13, e = 1.37), as evaluated from the results of the vinylidene chloride case, agree closely with the previously reported results of copolymerization with methyl methacrylate and acrylonitrile and confirm the general low reactivity of 4-cyclopentene-1,3-dione in nonalternating systems.     

Polymerization of meta-naphthoquinone methide: 3,4-benzo-6-methylenebicyclo [3.1.0] hex-3-ene-2-one

Polymerization behavior of meta-naphthoquinone methide, 3,4-benzo-6-methylenebicyclo[3.1.0]hex-3-ene-2-one ( 1 ), was studied. Radical initiator 2,2′-azobis(isobutyronitrile) (AIBN) induced polymerization of 1 , but ionic initiators potassium tert-butoxide, butyllithium, and boron trifluoride etherate did not. Polymerization of 1 proceeded via ring-opening and aromatization to give a polymer with head-to-tail monomer unit placement. Compound 1 copolymerized with methyl methacrylate (MMA) in the presence of AIBN to obtain the monomer reactivity ratios r₁ ( 1 ) = 0.28 ± 0.07 and r₂(MMA) = 0.39 ± 0.02 at 60°C and Q and e values of Q = 1.04 and e = −1.03, indicating that 1 is a conjugative and electron-donating monomer. Ring-opening and aromatization of 1 also took place in the copolymerization. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 741–746, 1997     

Radical homo- and copolymerizations of methyl α-trifluoroacetoxyacrylate

Radical homo- and copolymerizations of methyl α-trifluoroacetoxyacrylate (MTFAA) are studied by using azo initiators at 40 and 60°C. The rate of the homopolymerization of MTFAA was lower than that of methyl α-acetoxyacrylate. Monomer reactivity ratios (r), and Q and e values were estimated to be r₁ = 0.03, r₂ = 0.27, Q₁ = 0.65, and e₁ = 1.38 from the copolymerization of MTFAA (M₁) and styrene (M₂) at 60°C. Preferential crosspropagation was observed in particular in the copolymerization of MTFAA and α-methylstyrene. The influence of replacing the hydrogens of the acetoxy moiety of the acyloxyacrylate with the fluorines upon the copolymerization reactivity is discussed on the basis of the ¹³C-NMR chemical shift of various acyloxyacrylates. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 3537–3541, 1997     

Radical-initiated homo- and copolymerizations of methacryloyl fluoride

The kinetics of methacryloyl fluoride (MAF) homopolymerization was investigated in methyl ethyl ketone (MEK) with azobis(isobutyronitrile) as initiator. The rate of polymerization (R_p) followed the expression R_p = k[AIBN]^0.55[MAF]^1.18. The overall activation energy was calculated as 74.4 kJ/mol. The relative reactivity ratios of MAF(M₂) copolymerization with styrene (r₁ = 0.083, r₂ = 0.14), and methyl methacrylate (r₁ = 0.48, r₂ = 0.81) in methyl ethyl ketone were obtained. Application of the Q–e scheme (in styrene copolymerization) led to Q = 2.22 and e = 1.31. The glass transition temperature (T_g) of poly(MAF) was 90°C by thermomechanical analysis. Thermogravimetry of poly(MAF) showed a 10% weight loss of 228°C in air.     

Vinylhydroquinone. IV. Preparation and polymerization behavior of 2-methyl-5-vinylhydroquinone derivatives

As in the case of vinylhydroquinone (I), its alkyl-substituted derivative, 2-methyl-5-vinylhydroquinone (II) was found to copolymerize with methyl methacrylate by tri-n-butylborane in cyclohexanone at 30°C. II was prepared from the O,O′-bisether compound, 2-methyl-5-vinyl-O,O′-bis(1′-ethoxyethyl)hydroquinone (III). The monomer reactivity ratios (M₂ = II) were determined to be r₁ = 0.37 and r₂ = 0. No homopolymerization proceeded under the same conditions. Ordinary free-radical initiators, such as azobisisobutyronitrile and benzoyl peroxide, were not effective in the homopolymerization of II. 1:1 Copolymers were obtained from II and maleic anhydride by using tri-n-butylborane as an initiator. The copolymers exhibited no definite melting range and decomposed at 370–375°C endothermally (DSC). The polymerization behavior of III was also investigated. Although tri-n-butylborane did not initiate the homopolymerization of the monomer, azobisisobutyronitrile was capable of initiating the homopolymerization and copolymerization of III. The monomer reactivity ratios (M₁ = styrene) were determined to be r₁ = 0.83 and r₂ = 0.18. The ratios gave the following Q and e values; Q = 0.15 and e = ?2.2.     

Copolymerization of β-pinene with styrene oxide and N-vinylpyrrolidone

The copolymerization of β-pinene with styrene oxide (SO) and β-pinene with N-vinylpyrrolidone (VP) was investigated by using SnCl₄ in dichloromethane diluent at low temperature. Monomer reactivity ratios were evaluated for both copolymers at ?80°C; these are r₁(SO) = 2.979 and r₂(β-pinene) = 0.002 and r₁(VP) = 0.096 and r₂(β-pinene) = 0.294.