Controlling molecular weight and polymer architecture during the Passerini three component step-growth polymerization

A new approach to control the molecular weight and polymer architecture using the Passerini three-component step-growth polymerization is described. Starting from an AB-type monomer, linear homopolymers, diblock copolymers, as well as star-shaped polymers were synthesized in an efficient manner. By varying the ratio of the AB-type monomer and a suitable irreversible chain transfer agent (ICTA), different polymer architectures with specific molecular weights and high end-group fidelity were obtained

Integration of MALDI-TOFMS as high-throughput screening tool into the workflow of combinatorial polymer research

The possibilities of an integration of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) as an high-throughput screening tool into the workflow of combinatorial materials research are discussed. A multiple layer sample preparation technique for MALDI is described in detail and its possibilities of automation and miniaturization are discussed. Automated MALDI sample preparation could be performed within an automated synthesizer robot as well as with an ink-jet printer. The first approach offers the possibility of online reaction monitoring, whereas the second approach gives the opportunity of applications in ultra-high-throughput environments. Moreover, an example of high-throughput screening of a polymerization reaction by MALDI-TOFMS is discussed

Selected successful approaches in combinatorial materials research

Combinatorial materials research (CMR) is still a relatively young field of research. Nevertheless, it already provides successful strategies for a fast and accurate evaluation of a large variety of different research problems. Some of these approaches in CMR considering polymeric materials will be discussed and highlighted within this contribution by focussing on three prominent literature examples: structure-property relationships in biomaterials research, material properties evaluation utilizing thin film polymer libraries as well as the parallel and automated study of polymer based reversed unimol. micelles and their application possibilities. These examples are meant to demonstrate the almost unlimited possibilities of combinatorial approaches in polymer science rather than to provide an extended overview of the field. [on SciFinder (R)

Fluorescent Sensing of Transition Metal Ions Based on the Encapsulation of Dithranol in a Polymeric Core Shell Architecture

The encapsulation behaviour and the resulting transition metal ion sensing capabilities of a 5-arm star-shaped polymer bearing terpyridine ligands on its periphery are described

Automated synthesis of star-shaped block copolymers based on an 5-arm star poly(ethylene glycol) macro initiator

An example of a controlled living polymn. is the ring opening polymn. of lactides and lactones. This polymn. can be co-initiated by R-OH or R-NH2 functional groups, which open the ring monomers by a nucleophilic attack at the carbonyl C-atom. This results in a new R-OH functional group at the chain end of the oligomer/polymer, which can act as new co-initiator and propagation is achieved. In this study, we investigated the ring opening polymn. of lactides and lactones utilizing an automated synthesizer. Hereby, block copolymers with different mol. wts. were synthesized automatically and the reactions were monitored online by GPC to investigate the living character and the reproducibility of the polymns. carried out by the robo

Evaluation of a new multiple-layer spotting technique for matrix-assisted laser desorption/ionization time-of-flight mass spectrometry of synthetic polymers

A new multiple-layer matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) sample-spotting technique is described. This fast and easy technique was evaluated with poly(ethylene glycol) (PEG) standards and optimized conditions for these synthetic polymers were obtained. PEGs up to 35 kDa were detectable with this approach and single monomer resolution was observed up to 20 kDa. The spotting was performed using a multiple-layer approach, which offers the capability of complex sample preparation without the requirement of premixing the different matrix, analyte and doping salt solutions. The technique reduces the time required for sample preparation and offers high flexibility with respect to sample composition and solvents utilized for the crystallization of the compounds. The technique is thus perfectly suited for applications in combinatorial material research

Fluorescent Sensing of Transition Metal Ions Based on the Encapsulation of Dithranol in a Polymeric Core Shell Architecture

The encapsulation behaviour and the resulting transition metal ion sensing capabilities of a 5-arm star-shaped polymer bearing terpyridine ligands on its periphery are described