An Organoborane Vinyl Monomer with Styrene-like Radical Reactivity: Reactivity Ratios and Role of Aromaticity

2018 ◽  
Vol 51 (16) ◽  
pp. 6359-6368 ◽  
Author(s):  
Heidi L. van de Wouw ◽  
Elorm C. Awuyah ◽  
Jodie I. Baris ◽  
Rebekka S. Klausen
Keyword(s):  
Vinyl Monomer ◽  
Reactivity Ratios ◽  
Radical Reactivity

A Linearization Procedure for Determining Radical Reactivity Ratios in Restricted Penultimate Copolymerization Systems, 2

2008 ◽  
Vol 29 (9) ◽  
pp. 695-712 ◽  
Author(s):  
Franz Hinkelmann ◽  
Oskar Friedrich Olaj ◽  
Irene Schnöll-Bitai ◽  
Gerhard Zifferer
Keyword(s):  
Reactivity Ratios ◽  
Radical Reactivity

scholarly journals Photoinduced Copolymerization of APMP-MMA: The Role of Reactive Hindered Amine APMP

2016 ◽  
Vol 2016 ◽  
pp. 1-10
Author(s):  
Ting Zhang ◽  
Liuwa Fu ◽  
Zhikang Chen ◽  
Yanyan Cui ◽  
Xiaoxuan Liu
Keyword(s):  
Average Molecular Weight ◽  
Polymeric Materials ◽  
Radical Copolymerization ◽  
Reactivity Ratios ◽  
Free Radical Copolymerization ◽  
H Nmr ◽  
Initial Monomer ◽  
Monomer Feed ◽  
Low Toxicity

4-Acryloyl-1,2,2,6,6-pentamethyl-piperidinol (APMP) is a reactive hindered amine that prolongs the service life of the polymeric materials and exhibits high stability, good resistance to extraction, and low toxicity. In this paper, a photoinduced free radical copolymerization of APMP and methyl methacrylate (MMA) is accomplished at ambient temperature in solution. APMP plays a key role in the copolymerization, owing to the nitroxides generated in situ from the moiety of 1,2,2,6,6-pentamethyl-piperidine under UV irradiation, and mediates the copolymerization, which is confirmed by the linear kinetics. With the increment of initial monomer feed ratios of APMP/MMA, both the copolymerization rate and the average molecular weight increase. According to the reactivity ratios from the extended Kelen-Tüdos (KT) method at high conversion by1H NMR spectroscopy, a nonlinear model is established and the sequential distribution in the copolymers is also investigated. The dispersion of APMP units is regulated by the feed ratios and reactivity ratios.

The formation and destruction of pentenes during the combustion of pentane

1978 ◽  
Vol 364 (1716) ◽  
pp. 75-88 ◽  
Keyword(s):  
Chain Length ◽  
Sharp Decrease ◽  
Carbon Chain ◽  
Carbon Chain Length ◽  
Reactivity Ratios ◽  
Direct Products ◽  
Specific Activities ◽  
Kinetics Of ◽  
Quantitative Importance

Studies have been made of the quantitative rôle of pent-1-ene and pent-2-ene in the combustion of pentane at temperatures below 400°C. The present results show that, under these conditions, pentenes are initial and direct products of pentane combustion and pent-2-ene is the principal conjugate alkene formed [1- 14 C]Pent-1-ene and [2- 14 C]pent-2-ene have been synthesized and the combustion of pentane has also been investigated in the presence of small concentrations of these specifically labelled com­pounds; control experiments have shown that the pentenes, in the amounts added, do not interfere appreciably with the kinetics of pentane combustion. Measurements of the variation with time of the specific activities and concentrations of the pentenes enable the separate rates of formation and destruction of the conjugate alkenes to be determined. Hence it is possible to calculate the total quantities of these compounds formed at different stages of reaction and to show to what extent these are greater than the net amounts revealed by conventional analytical measurements; the differences are found to be most marked at small conversions. The reactivity ratios of pentane and the pentenes have also been determined. The rates of destruction of both pentenes are much greater than that of pentane; pent-2-ene is removed from the system roughly twice as fast as pent-1-ene. An important contrast between the behaviour of pentane and butane is that, between 300 and 400°C, but-1-ene is a much more abundant product than but-2-ene. However, with both alkanes, the relative amounts of the alk-1-enes formed become greater as the temperature is increased; indeed, the rate of formation of pent-1-ene considerably exceeds that of pent-2-ene at the instant of the passage of a strong cool flame. Comparison of the total amounts of conjugate alkenes formed from the two alkanes at 315°C shows that only ca . 30% of the pentane consumed is converted to pentenes, whereas nearly 75% of the butane which has reacted is converted to butenes. Thus there is clearly a sharp decrease in the quantitative importance of conjugate alkenes as the carbon chain length is increased from C 4 to C 5 . This suggests that the predominant reaction of pentyl radicals, under the conditions used, is to add on oxygen to form pentylperoxy radicals.

Determining chemospecificity in reactions with chain transfer agent and corresponding radical via evaluation of molecular weight dependency of apparent comonomer reactivity ratios: free-radical copolymerization of vinyl acetate and dibutyl maleate

RSC Advances ◽  
2016 ◽  
Vol 6 (111) ◽  
pp. 109759-109768 ◽  
Author(s):  
Seyed Saeid Rahdar ◽  
Mahdi Abdollahi ◽  
Ebrahim Ahmadi ◽  
Abbas Biglari
Keyword(s):  
Molecular Weight ◽  
Free Radical ◽  
Chain Transfer ◽  
Radical Copolymerization ◽  
Reactivity Ratios ◽  
Free Radical Copolymerization ◽  
Molecular Weights ◽  
Radical Reactivity ◽  
Dibutyl Maleate ◽  
Trichloromethyl Radical

Performing copolymerization with two different conditions leading to different molecular weights allows us to determine trichloromethyl radical reactivity towards comonomers.

Role of hydrogen bonding with medium molecules in the radical reactivity of phenols

1975 ◽  
pp. 15-16 ◽  
Author(s):  
Miklós Simonyi ◽  
Julianna Kardos ◽  
Ilona Fitos ◽  
Ilona Kovács
Keyword(s):  
Hydrogen Bonding ◽  
Radical Reactivity

The Measurement and Meaning of Radical Reactivity Ratios

1998 ◽  
pp. 120-144 ◽  
Author(s):  
Johan P. A. Heuts ◽  
Michelle L. Coote ◽  
Thomas P. Davis ◽  
Lloyd P. M. Johnston
Keyword(s):  
Reactivity Ratios ◽  
Radical Reactivity
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