Heterogeneous copper catalyzed azide-alkyne click chemistry (CuAAc) has been a quickly emerging research field during the last couple of years as it shows many advantages in comparison to its homogeneous counterpart. In this Minireview, an overview of the state-of-the-art is presented for the first time. For the sake of completeness, not only successful heterogeneous supports but also systems that particularly failed will be discussed. Furthermore, the future prospects and challenges with regard to the application of heterogeneous CuAAC are highlighted.

Pulsed laser polymerization (PLP) coupled to size exclusion chromatography (SEC) is considered to be the most accurate and reliable technique for the determination of absolute propagation rate coefficients, kp. Herein, kp data as a function of temperature were determined via PLP‐SEC for three acrylate monomers that are of particular synthetic interest (e.g., for the generation of amphiphilic block copolymers). The high‐Tg monomer isobornyl acrylate (iBoA) as well as the precursor monomers for the synthesis of hydrophilic poly(acrylic acid), tert‐butyl acrylate (tBuA), and 1‐ethoxyethyl acrylate (EEA) were investigated with respect to their propagation rate coefficient in a wide temperature range. By application of a 500 Hz laser repetition rate, data could be obtained up to a temperature of 80 °C. To arrive at absolute values for kp, the Mark‐Houwink parameters of the polymers have been determined via on‐line light scattering and viscosimetry measurements. These read: K = 5.00 × 105 dL g−1, a = 0.75 (piBoA), K = 19.7 × 105 dL g−1, a = 0.66 (ptBA) and K = 1.53 × 105 dL g−1, a = 0.85 (pEEA). The bulky iBoA monomer shows the lowest propagation rate coefficient among the three monomers, while EEA is the fastest. The activation energies and Arrhenius factors read: (iBoA): log(A/L mol−1 s−1) = 7.05 and EA = 17.0 kJ mol−1; (tBuA): log(A/L mol−1 s−1) = 7.28 and EA = 17.5 kJ mol−1 and (EEA): log(A/L mol−1 s−1) = 6.80 and EA = 13.8 kJ mol−1. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6641–6654, 2009

A detailed kinetic modeling study of the atom transfer radical polymerization (ATRP) of isobornyl acrylate (iBoA) is presented. This study combines a detailed reaction scheme with a systematic approach to account for diffusional limitations. Calculated values for diffusion coefficients and the Williams-Landel-Ferry parameters for poly(iBoA) are based on rheological measurements. A good agreement with experimental data is obtained for the polymerization rate, average chain length, and polydispersity index in conditions ranging from 323 to 348 K for targeted chain lengths varying from 50 to 100 and initial activator/deactivator concentrations between 10-50/0-2.5 mol m -3 . In these conditions, βC-scission reactions are insignificant and backbiting reactions result in a slight decrease of the polymerization rate and level of control at high conversions only. Termination is subject to diffusional limitations during the whole ATRP, while diffusional limitations on deactivation cannot be neglected at higher conversion. Diffusional limitations are shown to be codetermined by the evolution of the chain length distribution of both the end-chain and mid-chain macromolecular species.

For the first time, a detailed study of the atom transfer radical polymerization of isobornyl acrylate (iBA) is reported. On the basis of these results, well‐defined PiBA‐containing block copolymers were synthesized, focussing on the preparation of amphiphilic poly(acrylic acid) (PAA) containing block copolymers. The precursor monomers 1‐ethoxyethyl acrylate (EEA) as well as tert‐butyl acrylate have been used to synthesize the PAA‐segments of the PiBA‐b‐PAA block copolymers. Finally, the synthesis of “block‐like” copolymers of PiBA and PEEA via a one‐pot procedure was investigated. By optimizing the copper and ligand concentration, and choosing the appropriate solvent, a controlled polymerization behaviour was obtained in all cases, as evidenced by a detailed kinetic analysis, GPC, NMR, and MALDI‐TOF data. Thermogravimetric analysis confirmed the quantitative transformation of the precursor polymer PEEA to the corresponding PAA‐containing copolymers. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1649–1661, 2008

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.