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Brett Helms

Publications and source records attributed to Brett Helms.

6 recordsLinked to original sources
PubMed2006

A versatile new monomer family: functionalized 4-vinyl-1,2,3-triazoles via click chemistry.

Using facile, highly modular synthetic approaches, a new monomer family based on a 1,2,3-triazole-4-vinyl building block has been prepared, and various functional derivatives have been obtained. Subsequent homo- and copolymerization of these novel functionalized monomers gives polymeric materials with unique physical properties, combining many attractive features of more traditional monomers, such as styrene, vinylpyridine, and meth/acrylates.

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PubMed2004

Dendronized linear polymers via "click chemistry".

Dendronized linear polymers are prepared from dendritic azides and poly(vinylacetylene) using "click chemistry." The Cu(I)-catalyzed Huisgen [2 + 3] cycloaddition is quantitative up to the third generation.

Journal Article↗
PubMed2002

The effect of macromolecular architecture in nanomaterials: a comparison of site isolation in porphyrin core dendrimers and their isomeric linear analogues.

The influence of macromolecular architecture on the physical properties of polymeric materials has been studied by comparing poly(benzyl ether) dendrons with their exact linear analogues. The results clearly confirm the anticipation that dendrimers are unique when compared to other architectures. Physical properties, from hydrodynamic volume to crystallinity, were shown to be different, and in a comparative study of core encapsulation in macromolecules of different architecture, energy transduction from the polymer backbone to a porphyrin core was shown to be different for dendrimers as compared to that of isomeric four- or eight-arm star polymers. Fluorescence excitation revealed strong, morphology dependent intramolecular energy transfer in the three macromolecular isomers investigated. Even at high generations, the dendrimers exhibited the most efficient energy transfer, thereby indicating that the dendritic architecture affords superior site isolation to the central porphyrin it surrounds.

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