Kinetics of Free Radical Telomerization

This paper presents a new theoretical method for the determination of the PMMA telomers functionality in order to better control the telomerization reaction. Telomers bearing a functional end‐group are obtained by telomerization of methyl methacrylate with thioglycolic acid, initiated either with 2,2′‐azoisobutyronitrile (AIBN) or with 4,4′‐azocyanopentanoic acid (ACPA). In both cases of initiation, the transfer constants of thioglycolic acid are determined and are respectively equal to 0.672 and 0.674. Then, these results were applied to this new method so as to predict and quantify the several structures of telomers obtained above. This method is based on both contribution of termination and transfer to mercaptan in Mayo's law and allows to quantify all the kinds of macromolecules with their both extremities. The influence of the telogen amount vs the functionality of telomers, that of the initiator concentration and that of the nature of the initiator are investigated and underlined the importance of each factor. Finally, theoretical telomer functionalities are compared with experimental ones by titration of acid functions and are in good agreement.

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“…La télomérisation du MMA avec des mercaptans a fait l'objet de nombreux travaux [6] menant à des composés fonctionnels ou non. Dans le Tab.…”

Section: Rappels Et Description Du Modèle Théoriqueunclassified

Etude de la télomérisation du méthacrylate de méthyle par l'acide thioglycolique. Application à la détermination des probabilités de structures des télomères synthétisés

Loubat

Boutevin²

2000

Macromol. Chem. Phys.

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“…Indeed, the P-H bond is relatively weak (70 Kcal Á mol À1 ) and the phosphonyl radical is generated in the presence of oxygenated radicals. [30][31][32] For our purpose, the last method was chosen to establish the radical addition of DAHP on the unsaturations, a way which has been studied by some authors from our team. [33][34][35] Sasin et al [36] have applied this reaction to unsaturated fat acids in order to obtain derivatives of a phosphonate fat acid.…”

Section: Resultsmentioning

confidence: 99%

Synthesis and Characterization of New Methacrylic Phosphonated Surface Active Monomer

Senhaji

Robin

Achchoubi

et al. 2004

Macro Chemistry & Physics

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Summary: The synthesis of novel methacrylic phosphonated surface‐active monomer by an original method is described. The crucial stage is the telomerization of undec‐10‐enyl acetate with dialkyl (alkyl = methyl or ethyl) hydrogenphosphonate. The phosphonated acetate obtained is selectively hydrolysed to give dialkyl(11‐hydroxyundecyl)phosphonate as a precursor. The alcohol function allows setting of methacrylic side, which is highly reactive in radical polymerization. Particularly, by mono‐dealkylation of dimethyl phosphonate in a selective and quantitative way, the potassium iodide permits to get, at one stage, the expected salt of sodium methyl phosphonate. The new surface‐active sodium methyl(11‐methacryloyloxyundecyl)phosphonate is characterized by 1H and 31P NMR. Its critical micelle concentration evaluated by conductometry is 2.4 × 10−2 mol · l−1.Synthesis of dialkyl(11‐methacryloyloxyundecyl)phosphonate (DAHP) without protection of alcohol function.imageSynthesis of dialkyl(11‐methacryloyloxyundecyl)phosphonate (DAHP) without protection of alcohol function.

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“…The telomerization reaction of monomers with phophorus-containing telogen has been studied by many authors [11][12][13][14][15][16] and its principle is presented in Figure 1.…”

Section: Resultsmentioning

confidence: 99%

Determination of the Kinetic Constants of the Telomerization of 10‐Undecenol with Alkyl Hydrogenphosphonate

Senhaji

Robin

Achoubi

et al. 2004

Macro Chemistry & Physics

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Summary: The telomerization of 10‐undecenol with alkyl hydrogenphosphonate was studied in order to synthesize telomers of different molecular weights. The study showed that telomers from 10‐undecenol could be obtained despite the fact that the double bond has a low reactivity. The kinetic constant Kp2/KTe was determined to be 7 × 10−4 l · mol−1 · s−1 at 135 °C and the transfer constant CT was 0.057. These values are normal for a low activity telogen such as hydrogenphosphonate and for slightly reactive monomers like 10‐undecenol.SEC chromatogram of telomers obtained in the reaction of 10‐undecenol addition.imageSEC chromatogram of telomers obtained in the reaction of 10‐undecenol addition.

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Kinetics of Free Radical Telomerization

Cited by 32 publications

References 34 publications

Etude de la télomérisation du méthacrylate de méthyle par l'acide thioglycolique. Application à la détermination des probabilités de structures des télomères synthétisés

Etude de la télomérisation du méthacrylate de méthyle par l'acide thioglycolique. Application à la détermination des probabilités de structures des télomères synthétisés

Synthesis and Characterization of New Methacrylic Phosphonated Surface Active Monomer

Determination of the Kinetic Constants of the Telomerization of 10‐Undecenol with Alkyl Hydrogenphosphonate

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