We present a new application of nitroxide mediated polymerization (NMP) for grafting of various elastomers onto the surfaces of silica nanoparticles (NPs) while ensuring colloidal stability and thus avoiding particle aggregation. While NMP has been used to graft chains from NP surfaces, our novel contributions are thus two-fold. We show for the first time that this methodology, initially demonstrated for styrene polymerization, can be extended to a variety of other relevant polymer chemistries, i.e., to isoprene, butadiene and styrene-butadiene rubber. We optimize the synthesis conditions for the different monomers under critical pressure conditions and characterize the grafted chains in solution by a combination of small angle x-ray and neutron scattering (with deuterated solvent labelling) to quantitatively describe the grafted chain composition. Second, crucially, we characterized the colloidal stability of the particles during the different steps of the grafting process. We have found that particle aggregation can (and does) occur at a variety of points during synthesis, and hence we have performed a detailed refined characterization of NP agglomeration and then found methods to mitigate it at each stage. These steps ensure that we can begin the preparation of composite materials from a well-defined starting point.

我们提出了氮氧化物介导的聚合反应（NMP）在将各种弹性体接枝到二氧化硅纳米颗粒（NPs）表面上的新应用，同时确保了胶体稳定性，从而避免了颗粒聚集。虽然NMP已用于从NP表面接枝链，但我们的新贡献是双重的。我们首次展示了这种最初用于苯乙烯聚合的方法，可以扩展到其他各种相关的聚合物化学领域，即异戊二烯，丁二烯和丁苯橡胶。我们优化了临界压力条件下不同单体的合成条件，并通过小角度X射线和中子散射（具有氘代溶剂标记）的组合来表征溶液中的​​接枝链，以定量描述接枝链的组成。其次，至关重要的是，我们在接枝过程的不同步骤中表征了颗粒的胶体稳定性。我们发现在合成过程中粒子聚集可以（并且确实）发生在各个点，因此，我们对NP团聚进行了详细的细化表征，然后找到了在每个阶段减轻颗粒团聚的方法。这些步骤确保我们可以从明确的起点开始复合材料的制备。