Abstract:

In this project, both room temperature and cryogenic transmission electron microscopy (TEM) samples were made and inserted into TEM instrument. TEM images of the grafted nanoparticles (NPs) listed are shown individually to exhibit the polymer band around the surface of the NP. TEM images of aggregated NP species were used to measure brush length of the polymers attached to the NPs.

Suggested Citation:

Christopher B Keller. 2020. Transmission electron microscopy (TEM) images of grafted PCL-b-POEGMA on silica nanoparticles (SiO2 NPs). Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/n7-1cxy-k784

Publications:

Keller, C. B., Walley, S. E., Jarand, C. W., He, J., Ejaz, M., Savin, D. A., & Grayson, S. M. (2021). Synthesis of poly(caprolactone)-block-poly[oligo(ethylene glycol)methyl methacrylate] amphiphilic grafted nanoparticles (AGNs) as improved oil dispersants. Polymer Chemistry, 12(33), 4758–4769. doi:10.1039/d1py00418b

Purpose:

Depicting the presence of attached polymer on the surface of Snowtex NPs. Visual increases in brush thickness indicate successful functionalization of the surface with graft from polymers, achieving desired structure-property relationships for dispersant capabilities.

Data Parameters and Units:

The file "GRIIDC TEM Data.xlsx" includes - TEM Image (1-5), Measured diameter (centimeters; cm), Calculated diameter (nanometers; nm), Measured brush thickness (cm), Calculated brush thickness (nm). Dataset also includes TEM images. Please note that the measurements were calculated relative to the scale bar. Images were printed full size, one per page and measured with a ruler. Scale bar measured to be 2.5 cm in length.

Methods:

Both room temperature & cryogenic TEM experiments were performed for the following study at 200 kV of high tension. Cryogenic TEM samples were made up at a concentration of 1.5 mg/mL in deionized water on a lacey/carbon 200 mesh copper TEM grid. Utilizing a FEI Vitrobot, 5 μL of sample were plunged into liquid ethane after being blotted once by filter paper for 1.5 sec at 100% humidity and a blot force of 1. After samples were frozen, they were kept at -170˚C in a cryogenic TEM stage until loading into the TEM instrument. Room temperature TEM sample were made up at a concentration of 1 mg/mL in ethanol and sonicated until dispersed. Solutions were spotted on Formvar carbon film supported, 200 mesh, square pore copper TEM grids. The grids dried ambiently before being inserted into the TEM instrument.

Instruments:

FEI TECNAI G2F30 TEM

Individual Files: