Organotin polymers: 10. Copolymerization parameters for di-(tri-n-butyltin) itaconate with methyl acrylate,ethyl acrylate,N-vinyl pyrrolidone and acrylonitrile

The monomer reactivity ratios for the copolymerization of di-(tri-n-butyltin) itaconate (M₁) with methyl acrylate (M₂), ethyl acrylate (M₂), N-vinyl pyrrolidone (M₂) and acrylonitrile (M₂) were found to be r₁ = 0.387, r₂ = 0.671; r₁ = 0.555, r₂ = 0.958; r₁ = 0.033, r₂ = 0.185 and r₁ = 0.441, r₂ = 0.425, respectively. Copolymerization reactions were carried out in solution at 60°C using 1 mol% AIBN, with copolymer compositions being determined by tin analysis. The Q and e values for di-(tri-n-butyltin) itaconate were calculated from the monomer reactivity ratios determined in the present and previous studies. The sequence distribution of the triad fractions for the systems studied were calculated at azeotropic compositions.     

Synthesis of novel polymethacrylate bearing an (S)‐(+)‐1‐cyclohexylethyl urea group in the side chain and its chiral recognition ability

A new chiral methacrylate, (S)‐(+)‐1‐cyclohexylethyl‐(2‐methacryloyloxyethyl)urea (CEMOU), was synthesized from 2‐methacryloyloxyethyl isocyanate (MOI) and (S)‐(+)‐cyclohexylethylamine. Radical homopolymerization of CEMOU was performed in several solvents to obtain the corresponding chiral polymers having hydrogen bonds based on urea moieties. Specific optical rotations of poly(CEMOU) were slightly changed by the measurement temperature, which may be attributed in part to a change of conformation caused by hydrophobic interaction between the cyclohexyl groups. From the results of radical copolymerization of CEMOU (M₁) with styrene (ST, M₂) or methyl methacrylate (MMA, M₂), monomer reactivity ratios (r₁, r₂) and Alfrey–Price Q–e values were determined: r₁ = 0.89, r₂ = 0.12, Q₁ = 2.45, e₁ = 0.68 for the CEMOU–ST system; r₁ = 0.48, r₂ = 0.18, Q₁ = 8.39, e₁ = 1.97 for the CEMOU–MMA system. The chiroptical property of the poly(CEMOU‐co‐ST) was slightly influenced by the co‐units. Poly(CEMOU)‐bonded silica gel as the chiral stationary phase (CSP) was prepared for high‐performance liquid chromatography (HPLC). The CSP resolved trans‐2‐dibenzyl‐4,5‐di(o‐hydroxyphenyl)‐1,3‐dioxolane in normal phase such as n‐hexane/2‐propanol by HPLC. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1018–1025, 2003     

Synthesis and Polymerization of Novel Quinone Methide Ketals

Summary Novel quinone methide ketals, 8-[ 1'-cyano-1'-(ethoxycarbonyl)methylene]-l,4-dioxaspiro[4.5]deca-6,9-diene (1a) and 8-(1',l'-dicyanomethy1ene)-1,4-dioxaspiro[4.5]deca-6,9-diene (1b), were synthesized, and their polymerization behavior was investigated. Polymerizations of 1a and 1b initiated with BPO and BF₃·Et₂O gave corresponding novel ring-opening polymers, but no polymerization with BuLi. Copolymerization of 1a with St in the presence of AIBN at 60 °C gave the monomer reactivity ratios r₁(1a) = 0.50 ± 0.1 and r₂(St) = 0.1 ± 0.02, and Q and e values of 1a were 2.46 and +0.93, indicating that 1a is a highly conjugative, electron-accepting monomer. Homopolymers of 1a and 1b had better thermal stability than that of 7-cyano-7-(ethoxycarbonyl)- 1,4-benzoquinone methide. Received 23 January 2003/Revised version 28 February 2003/ Accepted 1 March 2003 Correspondence to Takahito Itoh     

Intramolecular charge transfer complexes: 1. Poly [N-(2-hydroxyethyl) carbazolyl methacrylate-co-picryl methacrylate]

The synthesis of an intramolecular charge transfer complex (CTC) was studied by radical copolymerization of N-(2-hydroxyethyl)carbazolyl methacrylate (M₁) with picryl methacrylate (M₂) in dioxane and benzene solutions. For the dioxane solution copolymerizations, the kinetic parameters of the reactions were determined to be: r₁₂ = 10.6; r_1C = 0.40; r_1C1 = 3.08; r_1C2 = 0.50 using the intermonomeric CTC mechanism. The intramolecular charge transfer interaction in the copolymer chain and the copolymer configuration and conformation influence on the intramolecular CTC were evidenced.     

N-halosuccinimide-mercaptoethanol cohalogenation of olefinic fatty methyl esters: Synthesis of β-halo thioethoxylates

Olefinic fatty methyl esters, undec-10-enoate (1), octadec-Z-9-enoate (2), methyl-12 hydroxy octadec-Z-9-enoate (3), on reaction with N-halosuccinimides (4,5), that is, N-bromosuccinimide (4) or N-chlorosuccinimide (5) and 2-mercaptoethanol (6) in benzene, gave β-bromo- or β-chlorothioethoxylates (8–13). β-Halothioethoxylates so formed were acetylated with acetyl chloride in CH₂Cl₂ to form the respective acetylated products (20–25).     

Synthesis and characterization of functional copolymers of citronellol with butylmethacrylate initiated by benzoyl peroxide

Benzoyl peroxide (BPO)‐initiated free radical copolymerization of citronellol with butylmethacrylate (BMA) in xylene at 80°C ± 0.1°C under the inert atmosphere of nitrogen has been studied. The kinetics expression is R_p α [I]^0.5±0.27 [citronellol]^1.0±0.13 [BMA]^1.0±0.18. The overall activation energy has been calculated as 65 kJ/mol. Bands at 3436 and 1732 cm^?1 in the FTIR spectrum of the copolymer(s) have indicated the presence of hydroxy, ester group of citronellol and butylmethacrylate, respectively. The ¹H‐NMR spectrum shows peaks at 7.0–7.7 δ due to ? OH proton of citronellol and at 3.2–4.0 δ due to ? OCH₂ proton of butylmethacrylate. The molecular weight M_v and η_int of the copolymers have been measured with the help of gel permeation chromatography in tetrahydrofuran at 25°C to calculate Mark‐Houwink constants as K = 2.68 × 10^?4 and α = 0.34 ± 0.40. The alternating nature of the copolymer is confirmed by reactivity ratios r₁ (BMA) = 0.023 ± 0.004 and r₂ (Citronellol) = 0.0025 ± 0.22. The Alfrey‐Price Q‐e parameters for citronellol have been calculated as Q₂ = 0.13 and e₂ = –1.28. Thermal decompositions of copolymer are evaluated with the help of thermal gravimetric analysis technique. The mechanism of copolymerization has been elucidated. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Cationic copolymerization of 1 ,3-pentadiene-with isoprene

The cationic copolymerization of 1,3-pentadiene (PD) with isoprene (IP) initiated by AICl₃, was carried out in toluene. The microstructure of the copolymer chain was characterized by IR and ¹H NMR. IP is incorporated in the copolymer chain mainly in cyclic segments. The PD–IP copolymer has a much higher cyclic content than the PD homopolymer, which shows that the cyclization reaction during PD polymerization is enhanced by the addition of IP. In addition, the reactivity ratios for IP(M₁) and PD(M₂) determined by the Kelen–Tudos method from low-conversion data are r₁ = 1.22 and r₂ = 1.09.     

New Sphingolipids with a Previously Unreported 9-Methyl-C<Subscript>20</Subscript>-sphingosine Moiety from a Marine Algous Endophytic Fungus <Emphasis Type="Italic">Aspergillus niger</Emphasis> EN-13

Asperamides A (1) and B (2), a sphingolipid and their corresponding glycosphingolipid possessing a hitherto unreported 9-methyl-C₂₀-sphingosine moiety, were characterized from the culture extract of Aspergillus niger EN-13, an endophytic fungus isolated from marine brown alga Colpomenia sinuosa. The structures were elucidated by spectroscopic and chemical methods as (2S,2′R,3R,3′E,4E,8E)-N-(2′-hydroxy-3′-hexadecenoyl)-9-methyl-4,8-icosadien-1,3-diol (1) and 1-O-β-d-glucopyranosyl-(2S,2′R,3R,3′E,4E,8E)-N-(2′-hydroxy-3′-hexadecenoyl)-9-methyl-4,8-icosadien-1,3-diol (2). In the antifungal assay, asperamide A (1) displayed moderate activity against Candida albicans.     

Spreadsheets in copolymerization studies

A Lotus spreadsheet (LS) was utilized as part of a copolymerization study of methyl methacrylate (MMA) with N-phenylmaleimide (MP) and with some derivatives of MP, namely N-o-chlorophenylmaleimide (MOCP), N-p-tolylmaleimide (MPT), and N-o-tolylmaleimide (MOT). The use of LS provided a very rapid method to obtain values of copolymerization parameters which were in very good agreement with non-spreadsheet reported values. Further, a novel LS macro was developed which could be employed to ascertain the shape of the copolymer composition curve (copolymer composition as a function of monomer composition). Monomer reactivity ratios, r₁ and r₂, were determined as well as values of semi-empirical copolymerization parameters Q and e. An attempt was made to correlate the monomer structures used with the values of Q and e. An empirical decomposition temperature index (DTI) was also devised to measure the thermal stability of copolymers of MMA and MP as a function of MP content. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 891–900, 1997     

Radical copolymerization of (−)-menthyl 2-acetamidoacrylate and styrene or methyl methacrylate near ceiling temperature

Radical copolymerization of chiral monomer, (−)-menthyl 2-acetamidoacrylate (1), with low ceiling temperature (T_c = 62.0 °C in [monomer] = 1.0 mol/L) and styrene or methyl methacrylate (MMA) has been studied near ceiling temperature (60 °C) and at the temperature lower than T_c (30 °C). Monomer reactivity ratios and Alfrey-Price Q and e-values of 1 are estimated to be r₁ = 0.27, r₂ = 0.067, Q = 3.0, and e = 1.2 at 30 °C, and r₁ = 0.32 and r₂ = 0.046 at 60 °C for the copolymerization of 1 (M₁) and styrene (M₂), suggesting an alternating tendency at both temperatures, whereas for the copolymerization of 1 (M₁) and MMA (M₂) r₁ and r₂ are estimated to be 2.9 and 0.019 at 30 °C, respectively, indicating longer sequence length of 1. Specific rotation and circular dichroism of the resulting copolymer indicate that styrene, in particular, is effectively incorporated into a helical copolymer structure at 60 °C and even only 25 mol% incorporation of the acetamidoacrylate unit in the copolymer induces the helix formation in solution.     

Copolymerization of 2-methoxy-4-vinylphenol with fluorinated acrylic monomers: Water-repellent properties of copolymer

To prepare the copolymer, which is water and oil repellent and contains the hydroxyl group, 2-methoxy-4-vinylphenol (VG: M₁) is copolymerized with the fluorinated acrylic monomer (M₂). The copolymerizability of VG (vinyl guaiacol) with pentadecafluoroctylacrylate (PDFOA) is best (r₁ = 0.217, r₂ = 0.0751). The critical surface tension γC of the copolymer of F₁ = 0.451 (F₁ is the ratio of M₁ units in the copolymer) is estimated to be 13.5 dyne/cm which is close to that of the homopolymer (F₁ = 0). The γc of the other copolymers are so small that they are 18.5 dyne/cm for copoly(VG-trifluoroethylmethacrylate) of F₁ = 0.491 and 17.8 dyne/cm for copoly(VG-fluoro-pentylmethacrylate) of F₁ = 0.392. Thus, these copolymers are water and oil repellent. Further, because of the hydroxyl, they provide hydrogen bonding to hydroxyapatite of teeth.     

Electrochemical behavior of a new <Emphasis Type="Italic">s</Emphasis>-triazine-based dendrimer

The electrochemical behavior of a new G-2-s-triazine-based dendrimer, 2,4,6-tris-{4-{4,6-bis-{4-{4,6-bis-[(1S,2S)-1,3-dihydroxy-1-(4-nitrophenyl)-prop-2-ylamino]-s-triazin-2-yl}-piperazin-1-yl}-s-triazin-2-yl}-piperazin-1-yl}-s-triazine, (I), was studied in dimethylsulfoxide solution by cyclic voltammetry, on platinum and graphite electrodes. The electrochemical properties of I were compared with that of one of its precursor, N-{4,6-bis{4-{4,6-bis[(1S,2S)-1,3-dihydroxy-1-(4-nitrophenyl)-prop-2-ylamino]-s-triazin-2-yl}-piperazin-1-yl}-triazin-2-yl}-piperazine), (II), together with that of the starting material, (1S,2S)-2-amino-1-(4-nitrophenyl)-propane-1,3-diol (“p-nitrophenylserinol”), (III).     

Copolymerization of vinylferrocene and N-vinylcarbazole. Conductivity studies of the trinitrofluorenone and mixed-valence [Fe(II), Fe(III)] complexes of these copolymers

Vinylferrocene (M₁) has been copolymerized with N-vinylcarbazole (M₂) using azobisisobutyronitrile as the initiator. In benzene at 70°C, the reactivity ratios r₁ = 0.47 and r₂ = 0.20 were obtained. Using an e value of ?1.34 for N-vinylcarbazole, the calculated value e for vinylferrocene is about ?2.8, in general agreement with the large negative e values vinylferrocene exhibits with other monomers which are electron rich. These copolymers were treated with trinitrofluororenone to give copolymers with carbazole–trinitrofluorenone charge–transfer complex sites (type B). The copolymers were oxidized with dichlorodicyanoquinone to give a series of copolymers with both ferrocenium and ferrocene sites in them (type C). In addition, type C copolymers were further treated with trinitrofluorenone to give a class of polymers having ferrocene, ferrocenium and carbazole–trinitrofluorenone charge–transfer sites (type D). Introducing ferrocene and ferrocenium sites into the poly(vinylcarbazole–trinitrofluorenone) polymers resulted in an increase in their conductivity, but the polymers were no longer photoconducting.     

In-chain functionalization by alternating anionic copolymerization of styrene and 1-(4-dimethylaminophenyl)-1-phenylethylene

Anionic copolymerizations of styrene (M₁) with excess 1-(4-dimethyl-aminophenyl)-1-phenylethylene (M₂) were conducted in benzene at 25°C for 24h, using sec-butyllithium as initiator. Narrow molecular weight distribution copolymers with M?;_n = 16.1 × 10³ g/mol (M?_w/M?_n = 1.04) and 38.2 × 10³g/mol (M?_w/M?_n = 1.05), and 24 and 38 moles of M₂ per macromolecule, respectively, were characterized by size exclusion chromatography, ¹H NMR spectroscopy and DSC. The monomer reactivity ratio, r₁ = 5.6, was obtained from the copolymer composition at complete consumption of M₁, assuming that the rate constant k₂₂ =0,i.e. r₂ =0. The polymers exhibited T_g values of 128 and 119°C, respectively, which correspond to an estimated T_g = 217°C for the hypothetical homopolymer of M₂.     

Catalytic deNO x properties of novel vanadium oxide based open-framework materials

The deNO _x catalytic properties of a new class of open-framework structure materials, Li₆[Mn₃(H₂O)₁₂V₁₈O₄₂(XO₄)] · 24H₂O (X = V, S) (1), [Fe₃(H₂O)₁₂ V₁₈O₄₂(XO₄)] · 24H₂O (X = V, S) (2), [Co₃(H₂O)₁₂V₁₈O₄₂(XO₄)] · 24H₂O (X = V, S) (3), and Li₆[Ni ₃ ^II (H₂O)₁₂V ₁₆ ^VI V ₂ ^V O₄₂(SO₄)] · 24H₂O (4), have been studied. The crystal structures of these novel systems consist of three-dimensional arrays of vanadium oxide clusters {V₁₈O₄₂(XO₄)} , as building block units, interlinked by {–O–M–O–} (M = Mn, 1; M = Fe, 2; M = Co, 3; M = Ni, 4) bridges. Their open-framework structures contain cavities, similar to those observed in conventional zeolites, which are occupied by exchangeable cations and/or readily removable water of hydration. The catalysts derived from these materials were tested for the selective catalytic reduction (SCR) of nitrogen oxides {NO _x } into N₂ using a hydrocarbon, propylene, as the reducing agent. The catalysts were ineffective under lean burn conditions. However, the new catalysts, especially the one derived from the cobalt derivative (3), showed intriguing deNO _x activity under rich conditions. They remove up to ~ 99% of the toxic NO _x emissions in 1.5% O₂ with 100% selectivity to N₂. The active phase of the catalysts exhibit good stability, can be readily regenerated, and are selective to the desired product-N₂. The catalytic reactions occur at moderately low temperatures (400–500 °C). The catalysts were characterized by FT-IR, temperature programmed reactions (TPR and TPO), SEM, BET surface area measurements, elemental analysis, and X-ray diffraction (XRD). Additional advanced techniques were used to further characterize the catalyst phases that showed most promising deNO _x activity and increased tolerance to oxygen.     

Radical polymerization of (phenylethynyl)styrenes and characterization of poly(phenylethynyl)styrenes as a thermally curable material

Summary The radical polymerizations of 2-, 3-, and 4-(phenylethynyl)styrenes (1a–c) and the copolymerizations of 1a–c (M₁) with styrene (M₂) were carried out using AIBN as the initiator in toluene at 60°C. The number-average molecular weights (M _ns) were extremely low for poly(2-phenylethynylstyrene) (2a) and poly[(phenylethynyl)styrene-co-styrene] (3a), and increased in the order of 2a, 3a << 2b, 3b < 2c, 3c. Monomer reactivity ratios were determined as r ₁= 1.80 and r ₂= 0.51 for 1a, r ₁= 1.72 and r ₂= 0.53 for 1b, and r ₁= 3.17 and r ₂= 0.24 for 1c. Polymers 2a–c and 3a–c underwent an exothermic reaction at elevated temperature to form organic solvent-insoluble polymers. Although the decomposition of 2a was observed from 200°C, 2b and 2c exhibited a high heat-resistance property in both nitrogen and air atmospheres, in particular, 2b showed no significant weight loss below 450°C. Received: 28 January 1998/Accepted: 5 March 1998     

Radical polymerization and copolymerization behavior of 1-cyanoethanoyl-4-acryloylthiosemicarbzide

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.     

Synthesis and characterization of N‐acryloylcarbazole/methyl methacrylate copolymers

Copolymers of N‐acryloylcarbazole (A) and methyl methacrylate (M) were synthesized in different in‐feed ratios. The composition of the copolymer was determined by the help of ¹H NMR spectrum. The comonomer reactivity ratios determined by Kelen‐Tudos (KT) and nonlinear error‐in‐variables methods were r_A = 1.12 ± 0.16, r_M = 0.94 ± 0.14, and r_A = 1.05, r_M = 0.90, respectively. Complete spectral assignments of the ¹H and ¹³C ¹H NMR spectra of the copolymers were done by the help of distortionless enhancement by polarization transfer (DEPT) and two‐dimensional NMR techniques, such as heteronuclear single quantum coherence (HSQC), total correlation spectroscopy (TOCSY), and heteronuclear multiple bond correlation (HMBC). The methine, α‐methyl, and carbonyl carbon resonances were found to be sequence sensitive. The signals obtained were broad because of the restricted rotation of bulky carbazole group and the quadrupolar effect of nitrogen present in carbazole moiety. Glass transition temperatures (T_g) were determined by differential scanning calorimetry and were found to be characteristic of copolymer composition. As the N‐acryloylcarbazole content increases, the T_g increases from 378.3 K for poly(methyl methacrylate) to 430.4 K for poly(N‐acryloylcarbazole). Variation in T_g with the copolymer composition were found to be in good agreement with theoretical values obtained from Johnston and Barton equations. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2667–2676, 2006     

Synthesis and characterization of functional copolymer of Linalool and vinyl acetate: A kinetic study

Linalool (LIN) and vinyl acetate (VA) were copolymerized by benzoyl peroxide (BPO) in p‐xylene at 60°C for 90 min. The system follows nonideal kinetics: R_pα[I]^0.6[LIN]^1.2[VA]^1.1. It results in the formation of alternating copolymer as evidenced from reactivity ratios as r₁ (VA) = 0.01, r₂ (LIN) = 0.0015, which have been calculated by Kelen–Tudos method. The overall activation energy is 82 kJ/mol. The FTIR spectrum of the copolymer shows the presence of the band at 3425 cm^?1 due to alcoholic group of LIN and at 1641 cm^?1 due to >C?O group of VA. The ¹H‐NMR spectrum shows peaks at 7.0–7.7 δ due to hydroxy proton of LIN and at 1.0–1.4 δ due to acetoxy protons of VA. ¹³C‐NMR spectrum of copolymer shows peaks at 167 ppm due to acetoxy group and at 75–77 ppm due to C? OH group. The Alfrey–Price Q–e parameters for LIN has been calculated as Q₂ = 1.24 and e₂ = 3.11. The copolymer is highly thermally stable and has a glass transition temperature (T_g) of 85°C, evaluated from DSC studies. The mechanism of copolymerization has been elucidated. This article also reports measurement of Mark–Houwink constants in THF at 25°C by means of GPC as α = 0.8 and K = 3.0 × 10^?4 dl/g. The thermal decompositions of copolymer are established with the help of TGA technique. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1134–1143, 2004     

Copolymerization of methyl α-(chloromethy1)acrylate with styrene accompanied by addition-fragmentation chain transfer

Summary Copolymerization of methyl α-(chloromethy1)acrylate (MCMA, M₁) as homo-polymerizable addition-fragmentation chain transfer (AFCT) agent with styrene (St, M₂) was investigated. The monomer reactivity ratios were r ₁ = 0.12 and r ₂ = 0.18 at 60° C indicating high alternating tendency. The copolymers bearing the 2-carbomethoxy-2-propenyl (CH₂=C(C0₂Me)CH₂-) ω-end group formed by AFCT were submitted for ¹H-NMR structural analysis. The M _n, of copolymer and contribution of AFCT as end forming reactions decreased and increased with increasing MCMA content in comonomer, respectively. The propenyl end groups bound to the St and MCMA units were separately detected. Furthermore, it was concluded that the MCMA-St copolymerization involves not only AFCT but also chlorine abstraction by the poly(St) radical. Received: 21 October 2002/Accepted: 19 November 2002 Correspondence to Bunichiro Yamada