Functional Polystyrene Combs and Dendrigrafts, 1

Peripherally functionalized arborescent polystyrenes (PS) of various architectures and chain parameters (backbone DPn, number and DPn of branches, number of termini and functions) were prepared by covalently assembling different elementary building blocks of controlled DPn, synthesized using anionic and cationic polymerization techniques. These multifunctional dendritic macromolecules have narrow polydispersities (< 1,2), and exhibit molar masses ranging from 1 × 105 to 5 × 106 g/mol for combs, and from 3 × 106 to 13 × 106 g/mol for dendrigrafts. In this latter series the number of terminal bis(hydroxymethyl) functions per macromolecule can be as high as 2 000. The calculated loading capacity (number of functional groups/g of polymer) was found to depend mainly on the molar mass of the last PS building block. It can approach 10−3 eq/g for low PS DPn grafts (DPn ≈ 10). First generation dendrigrafts. magnified image First generation dendrigrafts.