Polymers with pendant isocyanate groups. II. Dual synthesis and properties of poly(acrylonitrile-co-styryl isocyanate)

The copolymer poly(acrylonitrile-co-styryl isocyanate) was prepared directly in bulk by radical initiation either from the monomer pair acrylonitrile–cinnamoyl azide or from the pair acrylonitrile–styryl isocyanate. The copolymerization parameters, calculated by the conventional scheme, are r₁, = 3.5 ± 0.5; r₂ = 0 ± 0.5, for the first pair and r₁ = 9 ± 0.5; r₂ = 0 ± 0.5 for the second pair. The basic physical properties (solubility, intrinsic viscosity, and thermal behavior) of the new copolymer were determined and the chemical reactions of the isocyanate group with alcohol and with dimethylformamide were investigated.     

Organotin polymers. IV. Binary and ternary copolymerizations of tributyltin acrylate and methacrylate with styrene,allyl methacrylate,butyl methacrylate,butyl acrylate,and acrylonitrile

The monomer reactivity ratios for the copolymerization of tributyltin acrylate with styrene and allyl methacrylate have been found to be r₁ = 0.213, r₂ = 1.910 and r₁ = 0.195, r₂ = 2.257, respectively. Also, the copolymerization parameters of tributyltin methacrylate with styrene and allyl methacrylate were as follows: r₁ = 0.256, r₂ = 1.104 and r₁ = 2.306, r₂ = 1.013. Copolymerization reactions were carried out in solution at 70°C using 1 mole % AIBN, and the copolymer compositions were determined by tin analysis. Ternary copolymerization of the three systems butyl methacrylate–tributyltin methacrylate–acrylonitrile, butyl acrylate–tributyltin methacrylate–acrylonitrile, and styrene–tributyltin acrylate–acrylonitrile have been studied, and the terpolymer composition of each system was determined through tin and nitrogen analyses. The variation of instantaneous and average terpolymer composition with conversion fit satisfactorily the experimental results over a wide range of conversion.     

Aminimides. XI. Modified polystyrenes containing pendent aminimide or isocyanate residues

The hydrochloride salt of 1,1-dimethyl-1-(2-hydroxypropyl)amine methacrylimide (DHA) was synthesized and shown to readily homo- and copolymerize with styrene to produce soluble polymers containing pendent quaternary ammonium groups. These polymers may be treated with base to provide modified polystyrenes containing pendent aminimide residues. The latter polymers may be thermolyzed in solution or in the solid phase to produce modified polystyrenes containing pendent isocyanate groups. If the thermolysis is carried out in the presence of “isocyanate reactive” moieties, high molecular weight, crosslinked polymers may be synthesized. The reactivity ratios of DHA · HCl with styrene were determined: r₁ = 0.33 and r₂ = 0.35. The Alfrey-Price Q and e values were also calculated: Q = 0.88 and e = 0.67.     

Radical polymerization of new functional monomer: methacryloyl isocyanate containing 3-chloro-1-propanol

A new functional monomer, methacryloyl isocyanate, containing 3-chloro-1-propanol (CPL-MAI), was prepared in a reaction of methacryloyl isocyanate (MAI) with 3-chloro-1-propanol (CPL) at low temperature and was characterized by IR, ¹H and ¹³C NMR spectra. Radical polymerization of CPL-MAI was studied in terms of the rate of polymerization, solvent effect, copolymerization, polymer modification and thermal properties. The rate of polymerization of CPL-MAI has been found to be smaller than that of styrene under the same conditions. Copolymerization of CPL-MAI (M₁) with styrene (M₂) in tetrahydrofuran (THF) was studied at 60°C. The monomer reactivity ratio was calculated to be r₁=0.26 and r₂=0.33 according to the method of Fineman–Ross. Poly(CPL-MAI) was easily modified by reacting with the sodium salt of carbazole leading to a displacement of 49% conversion. The TG curve for poly(CPL-MAI) is in two stages and shows two maxima peaks at 206 and 416°C.     

Radical polymerization of new functional monomers: Mono- and dimethacryloyl isocyanate containing bisphenol-A and its derivatives

New functional monomers mono-and dimethacryloyl isocyanate containing bisphenol-A were prepared on reaction of methacryloyl isocyanate (MAI) with bisphenol-A (BPA) and its derivatives at low temperature. The monomers thus obtained were characterized with IR, UV, and ¹H- and ¹³C-NMR spectra. Radical polymerization of mono-and dimethacryloyl isocyanate containing bisphenol-A and its derivatives was studied in terms of the rate of polymerization, solvent effect, copolymerization, thermal properties, and kinetic measurements of photocrosslinking. Polar solvents such as DMSO and NMP were found to slow the polymerization. Copolymerization of BPA-MAI (M₁) with MMA (M₂) in DMF was studied at 90°C. The monomer reactivity ratio was calculated to be r₁ = 0.17 and r₂ = 1.34 according to the method of Fineman–Ross. Functional polymers containing the allyl group were successfully modified and photocrosslinked on irradiation in the presence of benzoin isopropyl ether. The photocrosslinking process follows second-order kinetics. © 1996 John Wiley & Sons, Inc.     

Bulk copolymerization of dimethyl meta-isopropenyl benzyl isocyanate (TMI®): Determination of reactivity ratios

Dimethyl meta-isopropenyl benzyl isocyanate (TMI®) is a bifunctional monomer with an unsaturation and an isocyanate group. Bulk copolymerizations of TMI with styrene, methyl methacrylate, and n-butyl acrylate were investigated. Polymerizations were carried out to low conversions in sealed test tubes at 70°C. The copolymer composition was determined using Fourier transform infrared (FTIR) spectroscopy. The data were analyzed using the terminal, as well as restricted penultimate, model of copolymerization. The method of Kelen-Tudos was used to calculate the reactivity ratios according to the terminal model. A nonlinear regression analysis was also carried out. Low reactivity ratio values for TMI were obtained for the copolymerizations with styrene and methyl methacrylate as a result of the inability of TMI to undergo homopolymerization. The value was higher for the copolymerization with n-butyl acrylate. Composition diagrams were generated, and the range of TMI concentration in the monomer charge for the preferential incorporation of TMI in the copolymer was identified. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67: 559–568, 1998     

Semicontinuous emulsion copolymerization of acrylonitrile,butyl acrylate,and styrene

Semicontinuous emulsion copolymerization of acrylonitrile (M₁), butyl acrylate (M₂), and styrene (M₃) was investigated. The copolymerization proceeded under the conditions used with a high degree of conversion, whereby a stationary state characterized by a constant monomer mixture composition and a constant composition of the arising copolymer was achieved. From the analytically estimated free monomers and arising copolymer compositions, the reactivity ratios for the pair AN/BA r₁₂ = 0.71, r₂₁ = 1.17 and for the pair AN/Sty r₁₃ = 0.06, r₃₁ = 0.28 were calculated. The applicability of the reactivity ratios found was verified also for the ternary system acrylonitrile/butyl acrylate/styrene.     

Effect of partitioning of monomer on the reactivities of monomers in microemulsion

Copolymerization of styrene and 2‐hydroxyethyl methacrylate (2‐HEMA) was carried out in a microemulsion medium. The composition of the copolymers was estimated using proton ¹H‐NMR. The reactivity ratios of styrene and 2‐HEMA in ternary microemulsions were observed and were considerable different from those reported for solution and bulk polymerization. In monomer pairs with a considerable difference in polarity, partitioning of a monomer between the aqueous phase and the microemulsion droplets develops a concentration gradient, which can be calculated from the distribution coefficient of the monomer between the two phases. This approach has led to more reliable reactivity ratios for the monomers. The study of styrene–2‐HEMA copolymerization in a sodium dodecylsulfate‐based microemulsion resulted in r_S = 3.79 and r_H = 0.17 as apparent reactivity ratios and r_S = 0.57 and r_H = 23.24 as true reactivity ratios for styrene and 2‐HEMA, respectively. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1832–1837, 2002; DOI 10.1002/app.10401     

Radiation-induced copolymerization of vinylphosphonic dichloride with methyl methacrylate and styrene

The γ-ray-induced copolymerization of vinylphosphonic dichloride (VPDC) with methyl methacrylate (MMA) and styrene (St) was studied at 25°C (liquid phase) and ?78°C (Solid phase). The reaction mechanisms are discussed. The reactivity ratios for the copolymerization of the VPDC–MMA system were determined as follows: The difference between the reactivity between the liquid-phase (25°C) and solid-phase (?78°C) copolymerization is mainly attributable to the r₂ value. The behavior of the liquid-phase copolymerization of the VPDC–St system was anomalous, the r₁ value being negative in the range from 0 to 80 mole-% of VPDC monomer. In the solid-phase (?78°C) copolymerization for the VPDC–St system, the reactivity ratios r₁ and r₂ were 0.097 and 1.6, respectively. The rate of copolymerization (R_p) at 25°C, for both the VPDC–MMA and VPDC–St systems, passes a maximum point at a certain monomer concentration, suggesting that the composition of copolymer is considerably affected by R_p. This phenomenon was interpreted by the assumption that an energy transfer reaction from VPDC monomer to the other vinyl compound can easily occur.     

Reactivity ratios and copolymer properties of 2‐(diisopropylamino)ethyl methacrylate with methyl methacrylate and styrene

Free radical copolymerization kinetics of 2‐(diisopropylamino)ethyl methacrylate (DPA) with styrene (ST) or methyl methacrylate (MMA) was investigated and the corresponding copolymers obtained were characterized. Polymerization was performed using tert‐butylperoxy‐2‐ethylhexanoate (0.01 mol dm^?3) as initiator, isothermally (70 °C) to low conversions (<10 wt%) in a wide range of copolymer compositions (10 mol% steps). The reactivity ratios of the monomers were calculated using linear Kelen–Tüd?s (KT) and nonlinear Tidwell–Mortimer (TM) methods. The reactivity ratios for MMA/DPA were found to be r₁ = 0.99 and r₂ = 1.00 (KT), r₁ = 0.99 and r₂ = 1.03 (TM); for the ST/DPA system r₁ = 2.74, r₂ = 0.54 (KT) and r₁ = 2.48, r₂ = 0.49 (TM). It can be concluded that copolymerization of MMA with DPA is ideal while copolymerization of ST with DPA has a small but noticeable tendency for block copolymer building. The probabilities for formations of dyad and triad monomer sequences dependent on monomer compositions were calculated from the obtained reactivity ratios. The molar mass distribution, thermal stability and glass transition temperatures of synthesized copolymers were determined. Hydrophobicity of copolymers depending on the composition was determined using contact angle measurements, decreasing from hydrophobic polystyrene and poly(methyl methacrylate) to hydrophilic DPA. Copolymerization reactivity ratios are crucial for the control of copolymer structural properties and conversion heterogeneity that greatly influence the applications of copolymers as rheology modifiers of lubricating oils or in drug delivery systems. © 2015 Society of Chemical Industry     

Atom transfer radical homo‐ and copolymerization of styrene and methyl acrylate initiated with trichloromethyl‐ terminated poly(vinyl acetate) macroinitiator: A kinetic study

Atom transfer radical bulk copolymerization of styrene (St) and methyl acrylate (MA) initiated with trichloromethyl‐terminated poly(vinyl acetate) macroinitiator was performed in the presence of CuCl/PMDETA as a catalyst system at 90°C. Linear dependence of ln[M]₀/[M] versus time data along with narrow polydispersity of molecular weight distribution revealed that all the homo‐ and copolymerization reactions proceed according to the controlled/living characteristic. To obtain more reliable monomer reactivity ratios, the cumulative average copolymer composition at moderate to high conversion was determined by ¹H‐NMR spectroscopy. Reactivity ratios of St and MA were calculated by the extended Kelen‐Tudos (KT) and Mao‐Huglin (MH) methods to be r_St = 1.018 ± 0.060, r_MA = 0.177 ± 0.025 and r_St = 1.016 ± 0.053, r_MA = 0.179 ± 0.023, respectively, which are in a good agreement with those reported for the conventional free‐radical copolymerization of St and MA. Good agreement between the theoretical and experimental composition drifts in the comonomer mixture and copolymer as a function of the overall monomer conversion were observed, indicating that the reactivity ratios calculated by copolymer composition at the moderate to high conversion are accurate. Instantaneous copolymer composition curve and number‐average sequence length of comonomers in the copolymer indicated that the copolymerization system tends to produce a random copolymer. However, MA‐centered triad distribution results indicate that the spontaneous gradient copolymers can also be obtained when the mole fraction of MA in the initial comonomer mixture is high enough. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Monomer-to-water ratios as a tool in controlling emulsion copolymer composition: The methyl acrylate–indene system

A drifting copolymer composition as a function of conversion is an aspect typical of copolymerization. Reducing this so-called composition drift in batch copolymerizations will lead to a decrease in chemical heterogeneity of the copolymers formed. For monomer systems in which the more water-soluble monomer is also the more reactive one, theory predicts that composition drift in emulsion copolymerization can be reduced or even minimized by optimizing the monomer-to-water ratio. The monomer combination methyl acrylate–indene (MA–Ind) meets the requirements needed to minimize composition drift in batch emulsion copolymerization. Therefore, this monomer combination is chosen as a model monomer system in order to verify this theoretical prediction. Reactivity ratios needed for model predictions have been determined by low conversion bulk polymerization, resulting in r_MA = 0.92 ± 0.16 and r_Ind = 0.086 ± 0.025. Furthermore, emulsion copolymerization reactions at the same monomer mole fraction are performed at different monomer to water ratios. From the good agreement between experiments and theoretical predictions for MA–Ind, it was concluded that control and even minimization of composition drift in batch emulsion copolymerization for monomer systems in which the more water-soluble monomer is also the more reactive one is indeed possible by changing the initial monomer-to-water ratio of the reaction mixture provided that the reactivity ratios of both monomers are not too far from unity. © 1994 John Wiley & Sons, Inc.     

Radical polymerization of methacryloyl isocyanate containing 1-adamantanol

Summary Radical polymerization of the methacryloyl isocyanate containing 1-adamantanol (Ad-MAI) with AIBN in different solvents at 60°C was investigated. It is observed that polymerization is slower in polar solvents than in nonpolar ones. The rate of polymerization for Ad-MAI was found to be slower than those of Adph-MAI and MMA both in photopolymerization and in thermal polymerization. Copolymerization of Ad-MAI (M₁) with styrene (M₂) in benzene was studied at 60°C. The monomer reactivity ratio was calculated to be r₁=1.53 and r₂=0.76 according to the method of Fineman-Ross. The prominent glass transition temperature for poly(Ad-MAI) was observed at 142°C from global TSC spectrum. Received: 20 November 1998/Revised version: 16 February 1999/Accepted: 25 February 1999     

Preparation of poly(styrene‐co‐isobornyl methacrylate) beads having controlled glass transition temperature by suspension polymerization

The styrene (St) and isobornyl methacrylate (IBMA) random copolymer beads with controlled glass transition temperature (T_g), in the range of 105–158°C, were successfully prepared by suspension polymerization. The influence of the ratios of IBMA in monomer feeds on the copolymerization yields, the molecular weights and molecular weight distributions of the produced copolymers, the copolymer compositions and the T_gs of these copolymers was investigated systematically. The monomer reactivity ratios were r₁ (St) = 0.57 and r₂ (IBMA) = 0.20 with benzyl peroxide as initiator at 90°C, respectively. As the mass fraction of IBMA in monomer feeds was about 40 wt %, it was observed that the monomer conversion could be up to 90 wt %. The fractions of IBMA unit in copolymers were in the range of 35–40 wt % and T_gs of the corresponding copolymers were in the range of 119.6–128°C while the monomer conversion increased from 0 to greater than 90 wt %. In addition, the effects of other factors, such as the dispersants, polymerization time and the initiator concentration on the copolymerization were also discussed. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Monomer apparent reactivity ratios for acrylonitrile/ammonium itaconate radical copolymerization systems

Ammonium itaconate was first used to copolymerize with acrylonitrile. This was achieved by using azobisisobutyronitrile as the initiator and dimethyl sulfoxide as the solvent. Effects of copolymerization systems on monomer apparent reactivity ratios for acrylonitrile/ammonium itaconate copolymers were studied. The values of monomer apparent reactivity ratios were calculated by Kelen‐Tudos method. The apparent reactivity ratios in the aqueous suspension polymerization system are similar to those in the solution polymerization system at polymerization conversions of less than 18% [reactivity ratio of acrylonitrile (r_AN) = 0.47 ± 0.01, reactivity ratio of ammonium itaconate (r_AIA) = 3.08 ± 0.01]. At conversions of more than 50%, the changes of monomer apparent reactivity ratios become less prominent (r_AN = 0.68 ± 0.01, r_AIA = 2.47 ± 0.01). In water‐rich reaction medium [(H₂O/dimethylsulfoxide (DMSO) > 80/20)], the monomer apparent reactivity ratios are approximately equivalent to those in the aqueous suspension polymerization system. In DMSO‐rich reaction medium (DMSO/H₂O > 80/20), the apparent reactivity ratios are similar to those in the solution polymerization system. With an increase in the polarity of the solvent, the values of apparent reaction ratios both decrease. The values of apparent reaction ratios gradually tend to 1 with increasing the copolymerization temperature. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3920–3923, 2007     

Organotin polymers. VII. Copolymerization of triphenyltin methacrylate with some acrylic and methacrylic acid esters

The monomer reactivity ratios for the copolymerization of triphenyltin methacrylate with methyl acrylate, ethyl acrylate, and butyl acrylate have been found to be r₁ = 2.58, r₂ = 0.66, r₁ = 2.37, r₂ = 0.43, and r₁ = 1.27, r_0.39 = 0.39, respectively. also, the copolymerization parameters of triphenyltin methacrylate with methyl methacrylate and butyl methacrylate were as follows: r₁ = 0.94, r₂ = 0.99, and r₁ = 0.68, r₂ = 0.83, respectively. Copolymerization reactions were carried out in solution at 70°C using 1 mol % AIBN, and the copolymer compositions were determined by tin analysis. The sequence distribution of the alternating diad fractions for the systems studied were calculated at various feed compositions. The structure of the triphenyltin methacrylate monomer as well as its azeotropic copolymer with butyl methacrylate were investigated by IR spectroscopy.     

Copolymerization of butadiene with styrene using a rare‐earth metal compound – dialkylmagnesium – halohydrocarbon catalytic system

Copolymerizations of butadiene (Bd) with styrene (St) were carried out with catalytic systems composed of a rare‐earth compound, Mg(n‐Bu)₂ (di‐n‐butyl magnesium) and halohydrocarbon. Of all the rare earth catalysts examined, Nd(P₅₀₇)₃–Mg(n‐Bu)₂–CHCl₃ showed a high activity in the copolymerization under certain conditions: [Bd] = [St] = 1.8 mol l^?1, [Nd] = 6.0 × 10^?3 mol l^?1, Mg/Nd = 10, Cl/Nd = 10 (molar ratio), ageing for 2 h, copolymerization at 50 °C for 6–20 h. The copolymer of butadiene and styrene obtained has a relatively high styrene content (10–30 mol%), cis‐1,4 content in butadiene unit (85–90%), and molecular weight ([η] = 0.8–1 dL g^?1). Monomer reactivity ratios were estimated to be r_Bd = 36 and r_St = 0.36 in the copolymerization. © 2002 Society of Chemical Industry     

Controllable radical copolymerization of styrene and methyl methacrylate using 1,1,2,2‐tetraphenyl‐1,2‐bis(trimethylsilyloxy) ethane as initiator

Copolymerization of styrene (St) and methyl methacrylate (MMA) was carried out using 1,1,2,2‐tetraphenyl‐1,2‐bis (trimethylsilyloxy) ethane (TPSE) as initiator; the copolymerization proceeded via a “living” radical mechanism and the polymer molecular weight (M_w) increased with the conversion and polymerization time. The reactivity ratios for TPSE and azobisisobutyronitrile (AIBN) systems calculated by Finemann–Ross method were r_St = 0.216 ± 0.003, r_MMA= 0.403 ± 0.01 for the former and r_St= 0.52 ± 0.01, r_MMA= 0.46 ± 0.01 for the latter, respectively, and the difference between them and the effect of polymerization conditions on copolymerization are discussed. Thermal analysis proved that the copolymers obtained by TPSE system showed higher sequence regularity than that obtained by the AIBN system, and the sequence regularity increased with the content of styrene in copolymer chain segment. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 1474–1482, 2001     

Spontaneous copolymerization of N‐butyl maleimide and ethyl α‐phenyl acrylate with high alternating tendency

The copolymerization of N‐butyl maleimide (BMI) and ethyl α‐phenyl acrylate (EPA) was successfully carried out without an initiator. A high alternating tendency was observed. The Q, e values were derived by Alfrey–Price equations: Q = 0.09, e = 0.81 for BMI and Q = 0.21, e = ?0.5 for EPA, and the monomer reactivity ratios were r_BMI = 0.15 ± 0.01 and r_EPA = 0.18 ± 0.08, respectively. In this system BMI was donor and EPA was acceptor. The maximum copolymerization rate and molecular weight appeared at 70 mol % (BMI) in the feed ratio. The spontaneous alternating copolymerization was considered to be completed by a contact‐type charge‐transfer complex formed by the monomer pairs. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 355–360, 2004     

Copolymerization of itaconic acid monomethyl ester (1-carboxy-1-carbomethoxymethylethylene) with acrylonitrile in the presence of znci2

The copolymerization of itaconic acid monomethylester (1-carboxy-1-carbomethoxy-methylethylene) with acrylonitrile in presence and in absence of ZnCI₂ was investigated. The reactivity ratios of the monomer pairs itaconic acid monomethyl ester-acrylonitrile (r₁=0,05±0,02; r₂=0,21±0,02) and itaconic acid monomethylester/ZnCl₂-acrylonitrile (r₁=0,14±0,05; r₂=0,41±0,03) are determined by the Kelen-Tüd?s and Fineman-Ross method.