An improved mimetic compound for styrene "living" free radical polymerization. An initiator containing the "penultimate" unit

被引:42
作者
Skene, WG [1 ]
Scaiano, JC [1 ]
Yap, GPA [1 ]
机构
[1] Univ Ottawa, Dept Chem, Ottawa, ON K1N 6N5, Canada
关键词
D O I
10.1021/ma991924d
中图分类号
O63 [高分子化学(高聚物)];
学科分类号
070305 ; 080501 ; 081704 ;
摘要
A new thermal initiator for living free radical polymerization (LFRP) has been synthesized photochemically by coupling of the free radical TEMPO with the 1,3-aiphenyl-1-propyl radical. This initiator (4), which contains the penultimate monomer unit, is a much better mimetic compound than similar compounds derived from radicals with a single styrene moiety, such as the 2-phenylethyl radical (which yields adduct 2). In particular, 4 does not yield any disproportionation products, while other model compounds usually do. This is attributed to the lowest energy conformation of 4, which places the beta-hydrogen atoms in an unfavorable stereoelectronic arrangement to give disproportionation products. It is anticipated that the same situation will prevail in the polymer, and it is instrumental in determining the low polydispersities achievable with LFRP. This report includes a detailed study of the properties of 4, including its thermal decomposition and relevant free radical kinetics, as well as a comparison of the rotational barrier of 4 with that of 2.
引用
收藏
页码:3536 / 3542
页数:7
相关论文
共 41 条
[1]  
Anderson J. E., 1992, J CHEM SOC P2, V7, P1027
[2]  
ANDERSON JE, 1993, J CHEM SOC P2, V7, P1299
[3]   KINETICS OF NITROXIDE RADICAL TRAPPING .1. SOLVENT EFFECTS [J].
BECKWITH, ALJ ;
BOWRY, VW ;
INGOLD, KU .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1992, 114 (13) :4983-4992
[4]  
BENSON SW, 1964, ADV PHOTOCHEM, V2, P1
[5]   Nitroxide-mediated living radical polymerization: Determination of the rate coefficient for alkoxyamine C-O bond homolysis by quantitative ESR [J].
Bon, SAF ;
Chambard, G ;
German, AL .
MACROMOLECULES, 1999, 32 (25) :8269-8276
[6]   KINETICS OF NITROXIDE RADICAL TRAPPING .2. STRUCTURAL EFFECTS [J].
BOWRY, VW ;
INGOLD, KU .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1992, 114 (13) :4992-4996
[7]   ABSOLUTE RATE CONSTANTS FOR THE REACTIONS OF SOME CARBON-CENTERED RADICALS WITH 2,2,6,6-TETRAMETHYLPIPERIDINE-N-OXYL [J].
CHATEAUNEUF, J ;
LUSZTYK, J ;
INGOLD, KU .
JOURNAL OF ORGANIC CHEMISTRY, 1988, 53 (08) :1629-1632
[8]   Consensus multiplex PCR-restriction fragment length polymorphism (RFLP) for rapid detection of plant mitochondrial DNA polymorphism [J].
Chen, H ;
Sun, M .
MOLECULAR ECOLOGY, 1998, 7 (11) :1553-1556
[9]   Thermal stability of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) and related N-alkoxyamines [J].
Ciriano, MV ;
Korth, HG ;
van Scheppingen, WB ;
Mulder, P .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1999, 121 (27) :6375-6381
[10]   Photochemical synthesis of TEMPO-capped initiators for ''living'' free radical polymerization [J].
Connolly, TJ ;
Baldovi, MV ;
Mohtat, N ;
Scaiano, JC .
TETRAHEDRON LETTERS, 1996, 37 (28) :4919-4922