✦ LIBER ✦

Evaluation of propagation rate constants for the free radical polymerization of methacrylonitrile by pulsed laser photolysis

✍ Scribed by Devon A. Shipp; Trevor A. Smith; David H. Solomon; Graeme Moad

Publisher: John Wiley and Sons
Year: 1995
Tongue: English
Weight: 411 KB
Volume: 16
Category: Article
ISSN: 1022-1336
DOI: 10.1002/marc.1995.030161109

No coin nor oath required. For personal study only.

✦ Synopsis

Abstract

Propagation rate constants for the free radical polymerization of methacrylonitrile (MAN) have been obtained by pulsed laser photolysis (PLP). The temperature dependence of the propagation rate constants indicates a frequency factor of 10^(6,43 ± 0,26)^ L · mol^−1^ · s^−1^ and an activation energy of 29,7 ± 1,5 kJ · mol^−1^. These parameters suggest that the relatively slow rate of propagation in MAN polymerization in relation to other common monomers (methyl methacrylate, styrene) can be attributed to the relative steric bulk and stability of the propagation species.

📜 SIMILAR VOLUMES

Kinetics of free-radical polymerization

Kinetics of free-radical polymerization with chain-length-dependent constants under initiation by laser pulses: Effect of chain length dependence of propagation

✍ Anatolij N. Nikitin; Alexander V. Evseev 📂 Article 📅 1999 🏛 John Wiley and Sons 🌐 English ⚖ 216 KB 👁 2 views

A numerical procedure is developed which allows taking into account the chain length dependence of the termination and propagation constants for calculating molecular weight distributions (MWDs) formed under free-radical polymerization initiated by an arbitrary sequence of laser pulses. The law whe

Towards the propagation rate coefficient

Towards the propagation rate coefficient for the free-radical polymerization of 1,3-butadiene

✍ Friedhelm Bandermann; Claus Günther; Johannes Schweer 📂 Article 📅 1996 🏛 John Wiley and Sons 🌐 English ⚖ 811 KB

The propagation rate coefficient k, for the free-radical polymerization of 1,3-butadiene was determined as a function of temperature in the range of 30-60°C in bulk and as a function of the concentration of 1,3-butadiene in chlorobenzene at 50°C using a combination of a UV flash-lamp induced polymer

Absolute rate constants for reactions of

Absolute rate constants for reactions of free radicals in the high-temperature photolysis of formamide vapor. II. Amino radicals

✍ R. A. Back; T. Yokota 📂 Article 📅 1973 🏛 John Wiley and Sons 🌐 English ⚖ 376 KB

The rotating-sector method has been applied to the photoinitiated radical-chain decomposition of formamide at 300°C to measure the rate constant for the bimolecular disappearance of NH2 radicals. The decomposition is propagated by the reactions Conditions were chosen so that reaction (1) was rate c

A new method for evaluation of the chara

A new method for evaluation of the characteristic constant for primary radical termination in free radical polymerization

✍ H.Kh. Mahabadi; G. Meyerhoff 📂 Article 📅 1979 🏛 Elsevier Science 🌐 English ⚖ 461 KB

Absolute rate constants for reactions of

Absolute rate constants for reactions of free radicals in the high-temperature photolysis of formamide vapor. Part I. Carbamyl radicals

✍ T. Yokota; R. A. Back 📂 Article 📅 1973 🏛 John Wiley and Sons 🌐 English ⚖ 503 KB

The photolysis of formamide vapor at 2062 has been studied in a flow system with results essentially similar to those obtained previously under static conditions and higher conversions. The rotating-sector technique has been applied to the radical-chain decomposition of formamide under conditions (3

Rate Constants for the Addition of 2-Hyd

Rate Constants for the Addition of 2-Hydroxy-2-propyl Radicals to Alkenes in Solution studied by laser flash photolysis

✍ Rainer Martschke; Robert D. Farley; Hanns Fischer 📂 Article 📅 1997 🏛 John Wiley and Sons 🌐 German ⚖ 487 KB 👁 1 views

Absolute rate constants for the addition of the highly nucleophilic 2-hydroxy-2-propyl radical to eight fast-reacting 1and 1,l-disubstituted alkenes in MeOH at room temperature have been determined by laser flash photolysis. Also the absorption spectra of the 2-hydroxy-2-propyl and the benzylic and