Recently, we have demonstrated that small-sticky nanoparticles are much more effective in tuning macroscopic properties of PNCs than conventional big nanoparticles, suggesting a potential paradigm shift in PNCs design (Figure below). The advanced macroscopic properties of small nanoparticle PNCs (s-PNCs) include a large shift in glass temperature (~10 times larger than conventional nanoparticle PNCs (c-PNCs)), an unexpectedly high fragility index (up to 270), a high threshold of kinetic gelation (> 40 vol%), an apparent “fully disentanglement” of polymers with molecular weight of 100 kg/mol, and a processing favorable zero-shear viscosity. We proposed the origin of the large effects as (i) a finite desorption time between the small nanoparticle and polymer segment; (ii) the high mobility of the nanoparticles; (iii) the small sizes. This discovery opens new routes of tuning the macroscopic properties of PNCs. In this project, we aim to extend the newly discovered strategy to design novel high-performance polymer nanocomposites through precisely tuning the polymer matrix and the size and polymer-nanoparticle interactions through polymer chemistry.
Previous publications:
Cheng, S.; Xie, S.-J.; Carrillo, J.-M. Y.; Carroll, B.; Martin, H.; Cao, P.-F.; Dadmun, M. D.; Sumpter, B. G.; Novikov, V. N.; Schweizer, K. S.; Sokolov, A. P. Big effect of small nanoparticles: A shift in paradigm for polymer nanocomposites ACS Nano 2017, 11 (1), 752-759.