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Self‐Lubricating Nano‐Ball‐Bearings
Author(s) -
Brick C. M.,
Chan E. R.,
Glotzer S. C.,
Marchal J. C.,
Martin D. C.,
Laine R. M.
Publication year - 2007
Publication title -
advanced materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 10.707
H-Index - 527
eISSN - 1521-4095
pISSN - 0935-9648
DOI - 10.1002/adma.200601551
Subject(s) - alkyl , materials science , diffraction , alkylation , hydrocarbon , nano , ball (mathematics) , crystallography , organic chemistry , chemical engineering , composite material , chemistry , physics , optics , engineering , catalysis , geometry , mathematics
Friedel–Crafts alkylation of octaphenyloctasilsesquioxane (OPS) introduces a hydrocarbon layer around the rigid OPS core (see figure). Although periodic order is maintained even in the melt, as determined from X‐ray diffraction measurements, this layer provides access to low‐melting solids for butyl, hexyl, octyl, and decyl substituents. Because the alkyl groups interdigitate, the butyl and hexyl melts are stable to temperatures of ca. 400 °C, which is ca. 100 °C higher than the octyl and decyl compounds.