Atom Transfer Radical Polymerization ATRP: Concept, Application, Challenges and Future Development

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Atom Transfer Radical Polymerization
(ATRP)Concept, Application, Challenges and
Future Development

• Youqing Shen
• Departments of Chemical Engineering and
• Materials Science and Engineering
• McMaster University
• Hamilton, Ontario, CANADA L8S 4L7

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Living Polymerization
M0
Mn
Conv.
?
?
Mm
Mn
I0
Conversion

• Mn
• Structure

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Radical reactions

?
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Suppressing radical termination
Rt/Rp kt P2/kpMP
ktP/kpM

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ATRP Systems
Metal Ligand
Initiator CuBr, CuCl
Bipyridine
Multidentate
amine RuBr2
PPh3 Al(OiPr)3 FeBr2
PPh3 NiBr2 PPh3 PdBr2
PPh3
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2. ATRP Applications
A Synthesis of polymers with controlled
molecular weight
A PS standard B PS by ATRP C PS by AIBN
Patten, T.E., Xia, J, Abernathy, T.,
Matyjaszewki, K. Science 1996, 272, 866.
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Factors affecting the molecular weight control

• Fast initiation
• Rapid deactivation

Narrow MWD
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C-XInitiator ? C-Xpolymer
Initiator matches Monomer
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Rapid deactivation
Kp - Temperature
Conv.-can not go too high
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B Synthesis block copolymers
Macroinitiator method
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C Synthesis of star polymers
Matyjaszewski, K., Miller, P. J. Pyun, J.
Kickelbick, G. Diaamanti, Macromolecules 1999,
32, 6526
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D Hyperbranched Polymers
Monomer-Initiator
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E. Synthesis of End-functionalized Polymers
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Challenges for ATRP
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Solution to the Problem ?

• Catalyst supporting

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Mn and PDI vs conversion in MMA polymerization by
supported catalysts
Haddleton, Chem. Commun. 1999, 99.
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WHY?
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Future development
Develop high reactive catalysts