Chain transfer reactions by aliphatic mercaptans in the high-temperature polymerization of methylmethacrylate

Sorokina, Larisa; Radbil, T.I.; Sorokina, G.N.; Shtarkman, B.P.

doi:10.1016/0032-3950(83)90175-2

Cited by 3 publications

(4 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Determination of polymer dn/dc values was made with five solutions of concentrations between 0.002 and 0.01 g/mL. Because of the drift in zero values, the slope of the plot of versus c was used as dn/dc, rather than the intercept of a plot of An/c versus c. The data gathered, while suffering from scatter, do suggest that the polymer dn/dc is related to the initial comonomer volume fraction degdma by the following:5 dn/dc [mL/g] = 0.113 + 0.006uEGDMA (8) This relation, used in interpreting all light scattering results, is in rough agreement with past results from PMMA18 and poly-…”

Section: Methodsmentioning

confidence: 99%

Nonidealities exhibited by crosslinking copolymerization of methyl methacrylate and ethylene glycol dimethacrylate

Dotson¹,

Diekmann²,

Macosko³

et al. 1992

Macromolecules

View full text Add to dashboard Cite

The predictions of classical theory for the establishment of a network by free-radical polymerization have been tested under conditions for which those predictions should be simple, i.e., short pregel regimes in which the composition and chain length distribution of the primary chains should be nearly invariant and for a nearly equally reactive system (methyl methacrylate/ethylene glycol dimethacrylate). At the moderate to high concentrations of cross-linker used, the classical theory is inapplicable, each of its predictions being disobeyed. Gelation occurs 1-2 orders of magnitude later than predicted, the gel point is relatively insensitive to the amount of cross-linker, the dependence on the primary chain length is weaker than the predicted inverse dependence, and the divergence of the weight-average molecular weight is more consistent with the percolation picture. All of these point to a violation of the mean-field picture, probably through cyclization and (size-dependent) reduction in the reactivity of the pendants.

show abstract

Section: Methodsmentioning

confidence: 99%

Nonidealities exhibited by crosslinking copolymerization of methyl methacrylate and ethylene glycol dimethacrylate

Dotson¹,

Diekmann²,

Macosko³

et al. 1992

Macromolecules

View full text Add to dashboard Cite

show abstract

“…7, given the assumptions prior to the calculation. The activation energy E trt is equal to 30 kJ/mol, to be compared with the value of 32.7 kJ/mol found by Sorokina [9]. Sorokina [9] and in the present work…”

Section: Polymerizations With Chain Transfer Agentmentioning

confidence: 93%

“…10, which makes the parameter estimation difficult. However, Sorokina [9] determined the value of k trt at high temperatures, from which it appears that the consumption of 1-Butanethiol by transfer can initially be neglected. Therefore we first determine k dt by assuming that k trt [T]λ 0 = 0, then the complete equation containing k trt is solved.…”

Section: Polymerizations With Chain Transfer Agentmentioning

confidence: 97%

Thermal Polymerization of Methyl Methacrylate at High Temperature

Fenouillot¹,

Terrisse²,

Rimlinger³

1998

International Polymer Processing

View full text Add to dashboard Cite

Kinetic studies of the bulk polymerization of methyl methacrylate at high temperature have been carried out first without any additives and then in the presence of 1-Butanethiol as a chain transfer agent. A pressurised dilatometric reactor operating at high temperature is used to determine the time-conversion curves at temperatures between 150 and 180°C. A two-stage polymerization is observed. The high polymerization rate obtained initially is attributed to traces of an initiating impurity, while the second, slower polymerization stage could be considered as the actual thermal polymerization. The chain transfer agent or an impurity it may contain also initiates the reaction. Therefore, the rates of both the initial polymerization and of the second stage are increased when the thiol is added.Experimental data on the degree of conversion versus time and on the final average molecular weight are used to determine the chain transfer constants to the monomer and to the mercaptan as well as the initiation rate constants. These constants are used to model the thermal polymerization of MMA at high temperatures where these initiation reactions can no longer be neglected, especially when an industrial polymerization process has to be optimized and controlled.

show abstract

“…There are many studies in the scientific literature that focus on the telomerization of methyl methacrylate (MMA) with functional mercaptans [ X – R –SH with X = OH, CO 2 H, or Aromatic (Ar), and R = C n H 2 n , with n = 1 to 18] 19–26. However, it is necessary to state that very few studies report the synthesis of functionalized amine telomers from (meth)acrylic monomers 27, 28.…”

Section: Introductionmentioning

confidence: 99%

Synthesis of functionalized amine oligomers by free‐radical telomerization of methyl methacrylate with a peculiar telogen: 2‐Aminoethanethiol hydrochloride

Boyer

Loubat

Robin

et al. 2004

J. Polym. Sci. A Polym. Chem.

View full text Add to dashboard Cite

The Telomerization of methyl methacrylate with 2-aminoethanethiol hydrochloride initiated by 2,2Ј-azobisisobutyronitrile, was investigated in dimethylformamide (DMF). First, the peculiar behavior of 2-aminoethanethiol was highlighted because it behaves as a peculiar transfer agent; this is because its transfer constant (C T ) is weak compared with that of other thiols. The presence of the amine function greatly disturbs the free radical telomerization reaction. Telomerization was performed in the presence of hydrochloric acid (HCl) to protect the amine group. The transfer constant was strongly influenced by the acid and water concentration. This work emphasized that the nature of the solvent plays an important role in the determination of the transfer constant. Thus, the value of C T increased from 0.23 in DMF to 0.56 in the HCl/DMF mixture. The primary and secondary amines were recovered after the reaction. The functionality of the primary and secondary amines was measured by titration. The influence of the concentration of HCl on the resulting amine functionality was investigated. The acid presence prevents the formation of secondary amines, arising from Michael's reaction, on methyl methacrylate. Finally, these results were applied to the synthesis of amine-functionalized telomers with molecular masses of 2000 to 15,000 g/mol. The amine function was correlated with the decrease of R 0 ([telogen]/[monomer]).

show abstract

Chain transfer reactions by aliphatic mercaptans in the high-temperature polymerization of methylmethacrylate

Cited by 3 publications

References 5 publications

Nonidealities exhibited by crosslinking copolymerization of methyl methacrylate and ethylene glycol dimethacrylate

Nonidealities exhibited by crosslinking copolymerization of methyl methacrylate and ethylene glycol dimethacrylate

Thermal Polymerization of Methyl Methacrylate at High Temperature

Synthesis of functionalized amine oligomers by free‐radical telomerization of methyl methacrylate with a peculiar telogen: 2‐Aminoethanethiol hydrochloride

Contact Info

Product

Resources

About