Amphiphilic polymers are regularly used to adsorb to solid nanoparticles and stabilize colloidal dispersions in non-solvents. However, little is known about how polymers behave at the surface of porous nanoparticles, such as metal-organic frameworks (MOFs), whose pore windows and diameters are commensurate with the statistical segmental length scale of flexible polymers. To stabilize MOF dispersions while maintaining accessibility of the internal pore surfaces to guest molecules, polymers must be designed to adsorb to the MOF surface without infiltrating and/or blocking the pores. Here we show how polymers’ chemistry and conformational rigidity influence their surface adsorption and infiltration into MOF pores in aqueous media. Specifically, while all amphiphilic polymers that were tested stabilize colloidal MOF dispersions in water, polymers with rigid backbones and large persistence lengths exhibit a significant barrier to pore infiltration. These insights are exploited to prevent polymer intrusion into MOF pores in aqueous dispersions.

Design rules for synthetic polymers to disperse metal-organic frameworks without infiltrating their pores

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.