Star-shaped poly(isobornyl acrylate) (PiBA) was prepared by atom transfer radical polymerization (ATRP) using multifunctional initiators. The optimal ATRP-conditions were determined to minimize star-star coupling and to preserve high end group functionality (>90%).Star-shaped PiBA with narrow polydispersity index was synthesized with 4, 6 and 12 arms and of varying molecular weight (10000 to 100000 g·mol -1 ) using 4 equivalents of a Cu(I)Br/PMDETA catalyst system in acetone. Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) analysis, NMR spectroscopy and size exclusion chromatography (SEC) confirmed their controlled synthesis. The bromine-end group of each arm was then transformed to a reactive end group by a nucleophilic substitution with methacrylic acid or cinnamic acid (conversion >90%).These reactive star polymers were used to prepare PiBA-nanoparticles by intramolecular polymerization of the end groups. The successful preparation of this new type of organic nanoparticles on a multi-gram scale was proven by NMR spectroscopy and SEC. Subsequently, they have been used as additives for linear, rubbery poly(n-butyl acrylate). Rheology measurements indicated that the viscoelastic properties of the resulting materials can be finetuned by changing the amount of incorporated nanoparticles (1-20 wt%), as a result of the entanglements between the nanoparticles and the linear polymers.

Reversible addition-fragmentation chain transfer (RAFT) polymerization techniques were utilized to polymerize N-acryloyl-L-phenylalanine methyl ester (L-Phe-OMe) and tetrahydropyranyl acrylate to afford amphiphilic star polymers (with 4 and 6 arms). These copolymer stars have a chiral hydrophobic core domain and can undergo further solution self-assembly to form well-defined nanostructures, which have been characterized using DLS, TEM, and cryo-TEM analysis. The characterization and properties of these novel chiral assemblies and their potential in racemic resolution are reported.

A combination of ATRP and RAFT Hetero Diels–Alder (HDA) conjugation is employed to efficiently generate well‐defined star blockcopolymers in a facile fashion. The presented approach demonstrates the versatility of the RAFT‐HDA click methodology. [Color figure can be viewed in the online issue, which is available at www.interscience.wiley.com.]

Well-defined functional star-shaped polymer structures with up to 29 arms have been successfully synthesized by the combination of atom transfer radical polymerization (ATRP) and click chemistry. First, azide end-functionalized poly(isobornyl acrylate) (PiBA) star-shaped polymers were prepared by successive ATRP and bromine substitution. Subsequently, alkyne end-functionalized molecules and polymers were introduced onto the star-shaped PiBA bearing pendant azide moieties by copper-catalyzed azide-alkyne cycloaddition (CuAAC). The possibilities and limits for the CuAAC on such highly branched polyacrylates are described.