The structural characterization of organotin compounds that are grafted onto insoluble cross‐linked polymers has necessarily been limited to elemental analysis, infrared spectroscopy, and in a few instances, solid‐state NMR spectroscopy. This important bottleneck in the development of such grafted systems has been addressed by using high‐resolution magic angle spinning (hr‐MAS) NMR spectroscopy. The great potential of this technique is demonstrated through the structural characterization of diphenylbutyl‐(3,4) and dichlorobutylstannanes (5,6), grafted onto divinylbenzene cross‐linked polystyrene by means of a suitable linker (1, 2). First, conditions suitable for the application of hr‐MAS NMR spectroscopy were identified by characterizing the 1H resonance line widths of the grafted organotin moiety following swelling of the functionalized beads in eight representative solvents. The presence of clearly identifiable tin coupling patterns in both the 1D 13C and 2D 1H‐13C HSQC spectra, and the incorporation of 119Sn chemical shift and connectivity information from hr‐MAS 1D 119Sn and 2D 1H‐119Sn HMQC spectra, provide an unprecedented level of characterization of grafted organotins directly at the solid/liquid interface. In addition, the use of hr‐MAS 119Sn NMR for reaction monitoring, impurity detection, and quantification and assessment of the extent of coordination reveals its promise as a novel tool for the investigation of polymer‐grafted organotin compounds. The approach described here should be sufficiently general for extension to a variety of other nuclei of interest in polymer‐supported organometallic chemistry.

Differently N-substituted maleimides were copolymerized with styrene to yield alternating styrene-maleimide copolymers (SMI-R) with different chain diameters. The polymers were obtained by free radical polymerization and characterized by NMR and size exclusion chromatography / differential viscometry. Glass transition temperatures were measured by differential scanning calorimetry. An increase in chain diameter and chain stiffness is accompanied by a decrease in the entanglement density, reflected in lower values of the plateau modulus, which were corrected for the low molecular weight portion using the Wasserman/Graessley model. Increasing the chain diameter by a factor of two results in a decrease of the entanglement density to one third. SMI-Me showed a much lower entanglement density than polystyrene (PS) although they have the same chain diameter. SMIMe however is more rigid than PS because of the maleimide five-membered ring structure in the main chain. SMI-Me and SMI-PhOPh show the same glass transition temperature. However, because of the larger chain diameter of SMIPhOPh, it has a much lower entanglement density. Thus, both the chain flexibility and the chain diameter, two parameters that are strongly related, affect the entanglement density.

UV and thermal polymerisations of styrene were carried out in the presence of conventional ‘iniferters’. The mechanisms of the two methods were investigated and provided new insight into the livingness of the so-called iniferter technique. Chain extension polymerisations were performed using symmetrical iniferters to check the living character of this technique under UV and thermal polymerization conditions. In accordance with the work of Otsu, we have shown that polymerisation under UV irradiation initiated by iniferters proceeds via the classical iniferter living (controlled) mechanism. On the other hand, thermal polymerisations were predominantly controlled by the reversible additionfragmentation chain transfer (RAFT) mechanism.