Cryo-polishing

The crosslinkable epoxy thermoplastic modified with 5 wt % grafted rubber concentrate (CET-GRC) was prepared according to published procedure (5). The rubber domains are nominally 0.1 micron in diameter and consist of a core-shell structure with a 0.03 micron diameter polystyrene seed. Blocks of the CET-GRC were cryo-polished at -90°C using a diamond knife to provide a smooth face for SPM imaging. Some of these surfaces were post stained in OSO4 vapors by suspending the polished blocks in sealed containers over an aqueous solution of... 

Figure 7. Contact mode AFM of CET-GRC (5 wt% rubber, 0.1 pm diameter) after cryo-polishing (top) and after staining in 0s04 vapor (bottom).

Figure 8. TappingMode AFM height and phase images of CET-GRG (5wt% rubber, 0.1 U,m diameter) after cryo-polishing (images are 1 Lim x 0.3 im). Table at far right indicates tapping parameters used to generate each pair of images as described in the text.

Typical SEM pictures of the hydrated pastes obtained with the cryo-procedure are shown on plate 1. The polished sections of the initial boehmite powder and of the dried and calcined pastes are shown on plate 2. 

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