Functional Hyperbranched Macromolecules Constructed from Acetylenic Triple-Bond Building Blocks - Functional Materials and Biomaterials - page 1

Functional Hyperbranched Macromolecules Constructed
from Acetylenic Triple-Bond Building Blocks

Matthias Häußler · Ben Zhong Tang ( )

Department of Chemistry, The Hong Kong University of Science & Technology,
Clear Water Bay, Kowloon, Hong Kong,
and Department of Polymer Science and Engineering, Zhejiang University,
310027 Hangzhou, China
[e-mail]

1 I tr cti n ................................... 4

2 Synthesis ..................................... 4

2.1 Polycoupling................................... 5

2.1.1 Palladium-CatalyzedPolycoupling....................... 5

2.1.2 MechanisticConsiderations........................... 8

2.1.3 Copper-CatalyzedPolycoupling......................... 9

2.2 Polyhydrosilylation ............................... 12

2.2.1 Platinum-CatalyzedPolyhydrosilylation.................... 13

2.2.2 Rhodium-andPalladium-CatalyzedPolyhydrosilylation........... 13

2.3 Polycycloaddition ................................ 14

2.3.1 Diels-AlderPolycycloaddition ......................... 14

2.3.2 1,3-DipolarPolycycloaddition(ClickPolymerization) ............ 15

2.4 Polycyclotrimerization ............................. 19

2.4.1 HyperbranchedPoly(alkylenephenylene)s................... 20

2.4.2 HyperbranchedPolyarylenes.......................... 26

2.4.3 HyperbranchedPoly(aroylarylene)s ...................... 33

3 r erties .................................... 37

3.1 ThermalandOpticalProperties ........................ 37

3.2 PatterningandAssemblingBehaviors..................... 43

3.3 Photonic,MagneticandCatalyticProperties ................. 48

4 cl i g e ar s .............................. 53

References ....................................... 54

Abstract This review article summarizes the synthetic efforts in constructing functional
hyperbranched macromolecules from acetylenic triple-bond building blocks. Polymeriza-
tion reactions including polycoupling, polyaddition and polycyclotrimerization have been
developed for the synthesis of new hyperbranched polymers such as polyynes, polyenes,
polyarylenes and polytriazoles with novel topological structures and electronic conjuga-
tions. Polymers with high molecular weights (up to > 1 × 10 6 ) have been obtained in high
yields (up to 100%). Whilst their linear counterparts are often intractable, the hyper-
branched conjugated polymers are completely soluble in common organic solvents and
are hence readily processable by macroscopic techniques. The hyperbranched polymers
exhibit an array of functional properties including strong light emission, stable optical