Kinetic and ESR studies on radical polymerization behavior ofN-(2-phenylethoxycarbonyl)methacrylamide

Seno, Makiko; Fukui, Tomoya; Hirano, Tomohiro; Sato, Tsuneyuki

doi:10.1002/1099-0518(20001201)38:23<4264::aid-pola120>3.0.co;2-3

Cited by 5 publications

(4 citation statements)

References 22 publications

(20 reference statements)

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“…The analysis of the Arrhenius parameters (Table 5) supports this suggestion. Favorable arrangement by association being responsible for low values of the activation energy and the pre-exponential factor was reported and discussed by several authors [14,51,52,53,54,55,56]. Considering their arguments, a more favorable arrangement due to concentration-dependent association seems to be responsible for the low values of E a and A estimated for di-M, Table 5.…”

Section: Discussionmentioning

confidence: 72%

“…This low number of solvent molecules could be insufficient for mono-molecular dissolution of the double-charged monomer cation and the two chloride counterions. Different reaction kinetics was reported for the polymerization of associated and isolated monomer molecules [14,51,52,53,54,55,56], and can therefore be hypothesized for the polymerization of di-M and di-A at the limits of high and low concentrations.…”

Section: Discussionmentioning

confidence: 99%

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Effect of Very High Charge Density and Monomer Constitution on the Synthesis and Properties of Cationic Polyelectrolytes

2016

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Abstract:The free-radical homopolymerization of 1,3-bis(N,N,N-trimethylammonium)-2-propylmethacrylate dichloride (di-M) and 1,3-bis(N,N,N-trimethylammonium)-2-propylacrylate dichloride (di-A) in aqueous solution yields cationic polyelectrolytes (PEL) with theoretical/structural charge spacing of only «0.12 nm. The high charge density causes condensation of «82% of the chloride counterions. The high level of counterion condensation reduces the ionic strength in the polymerizing batch when the monomer molecules connect to PEL chains. This has the consequence that the hydrodynamic and excluded volume of the PEL molecules will change. Studies of the free radical polymerization revealed non-ideal polymerization kinetics already at low conversion and additionally autoacceleration above a certain monomer concentration and conversion. Similar autoacceleration was not observed for monomers yielding PEL with charge spacing of 0.25 or 0.5 nm. Coulomb interactions, monomer association, steric effects, and specific features of the monomer constitution have been evaluated concerning their contributions to the concentration dependence and conversion dependence of kinetic parameters. The different backbone constitutions of di-M and di-A not only influence the polymerization kinetics but also equip poly(di-M) with higher hydrolytic stability. The experimental results confirm the impact of electrochemical parameters and the necessity to reconsider their inclusion in kinetic models.

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Section: Discussionmentioning

confidence: 72%

Section: Discussionmentioning

confidence: 99%

Effect of Very High Charge Density and Monomer Constitution on the Synthesis and Properties of Cationic Polyelectrolytes

2016

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“…Stereoregularity is a function of monomer structure, initiator, solvent, and temperature. [5][6][7][8][9][10][11][12] This is mainly because N-alkylmethacrylamides can be polymerized only via a radical mechanism owing to their acidic N-H protons, which do not allow vinyl polymerizations via anionic and coordination mecha- nisms. 4 However, stereochemical studies on the polymerization of N-alkylmethacrylamides ( Fig.…”

Section: Introductionmentioning

confidence: 99%

“…Although the stereoregularities of the poly(N-alkylmethacrylamide)s reported so far have been moderately syndiotactic, [5][6][7][8][9][10][11][12] a limited number of stereospecific radical polymerizations of N-alkylmethacrylamides have been reported in the last two decades. [24][25][26][27][28] For instance, poly(N-methylmethacrylamide) [ poly(NMMAAm)] with rr triad = 95% was prepared in (CF 3 ) 2 CHOH at −78°C.…”

Section: Introductionmentioning

confidence: 99%

Syndiotactic- and heterotactic-specific radical polymerization of N-n-propylmethacrylamide complexed with alkali metal ions

et al. 2015

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We investigated the radical polymerization of N-n-propylmethacrylamide (NNPMAAm) in the presence of alkali metal bis(trifluoromethanesulfonyl)imides (MNTf 2 ), in particular LiNTf 2 . The addition of MNTf 2 led to a significant improvement in the yield and molecular weight of the resulting poly(NNPMAAm)s. Furthermore, the solvent employed influenced stereospecificity in the presence of LiNTf 2 . The stoichiometry of the NNPMAAm-Li + complex appeared to be critical for determining the stereospecificity in the NNPMAAm polymerization. The 1 : 1-complexed monomer in protic polar solvents provided syndiotacticrich polymers, whereas the 2 : 1-complexed monomer in aprotic solvents gave heterotactic-rich polymers. Stereochemical analyses revealed that m-addition by an r-ended radical was the key step in the induction of heterotactic specificity in the aprotic solvents. Spectroscopic analyses suggested that the Li + cation played a dual role in the polymerization process, with Li + stabilizing the propagating radical species and also activating the incoming monomer. Kinetic studies with the aid of electron spin resonance spectroscopy revealed that the addition of LiNTf 2 caused a significant increase in the k p value and a decrease in the k t value. The stereoregularity of poly(NNPMAAm)s was found to influence the phase transition behavior of their aqueous solutions. In a series of syndiotactic-rich polymers, the phase-transition temperature decreased gradually with increase in the rr triad content. Furthermore, heterotactic-rich poly-(NNPMAAm) exhibited high hysteresis, which increased in magnitude with increasing mr triad content. † Electronic supplementary information (ESI) available: 13 C NMR spectra of the CvO group of NNPMAAm in the presence of MNTf 2 , changes in the chemical shifts of 1 H NMR spectra of the vinylidene group of NNPMAAm in the presence of LiNTf 2 , relationship between the radical concentration and time, additional ESR spectra and relationship between the ΔT c and n r values. See

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Determination of the Propagation Rate Coefficient of Vinyl Pivalate Based on EPR Quantification of the Propagating Radical Concentration

Kubota

Kajiwara

Zetterlund

et al. 2007

Macro Chemistry & Physics

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The propagation rate coefficient (kp) of the vinyl pivalate (VPi) has been determined from an EPR quantification of the concentration of propagating radicals. The polymerizations followed first‐order kinetics with respect to the monomer, and the concentration of propagating radicals did not vary with time. The chain lengths were estimated to be sufficiently large to not affect kp. The resulting Arrhenius parameters for kp of VPi in heptane are Ap = 1.39 × 107 dm3 · mol−1 · s−1 and Ep = 20.5 kJ · mol−1. They are very similar to those of vinyl acetate as previously determined by the PLP method. The present results thus indicate that EPR gives consistent kp values for vinyl esters.magnified image

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Kinetic and ESR studies on radical polymerization behavior ofN-(2-phenylethoxycarbonyl)methacrylamide

Cited by 5 publications

References 22 publications

Effect of Very High Charge Density and Monomer Constitution on the Synthesis and Properties of Cationic Polyelectrolytes

Effect of Very High Charge Density and Monomer Constitution on the Synthesis and Properties of Cationic Polyelectrolytes

Syndiotactic- and heterotactic-specific radical polymerization of N-n-propylmethacrylamide complexed with alkali metal ions

Determination of the Propagation Rate Coefficient of Vinyl Pivalate Based on EPR Quantification of the Propagating Radical Concentration

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