Multiscale Effects of Interfacial Polymer Confinement in Silica Nanocomposites

作者:Varol H Samet*; Sanchez M Alejandra; Lu Hao; Baio Joe E; Malm Christian; Encinas Noemi; Mermet Guyennet Marius R B; Martzel Nicolas; Bonn Daniel; Bonn Mischa; Weidner Tobias; Backus Ellen H G; Parekh Sapun H
来源:Macromolecules, 2015, 48(21): 7929-7937.
DOI:10.1021/acs.macromol.5b01111

摘要

Dispersing hydrophilic nanofillers in highly hydrophobic polymer matrices is widely used to tune the mechanical properties of composite material systems. The ability to control the dispersion of fillers is closely related to the mechanical tunability of such composites. In this work, we investigate the physical-chemical underpinnings of how simple end-group modification to one end of a styrene-butadiene chain modifies the dispersion of silica fillers in a polymer matrix. Using surface-sensitive spectroscopies, we directly show that polymer molecular orientation at the silica surface is strongly constrained for silanol functionalized polymers compared to nonfunctionalized polymers because of covalent interaction of silanol with silica. Silanol functionalization leads to reduced filler aggregation in composites. The results from this study demonstrate how minimal chemical modifications of polymer end groups are effective in modifying microstructural properties of composites by inducing molecular ordering of polymers at the surface of fillers.

  • 出版日期2015-11-10