ABSTRACTWyoming montmorillonite has been modified with block copolymers of poly
(styrene) (PS) and poly(ethylene oxide) (PEO). Using melt intercalation
techniques, PEO-b-PS copolymers spanning a range of volume fractions and
molecular weights were mixed with montmorillonite, annealed above the
Tg of PS, and characterized using X-ray diffraction. Most of
the block copolymers intercalated the clay, with several samples exhibiting
multiple Bragg reflections from increased gallery spacing. Samples with
higher PEO volume fractions were most likely to have intercalation. For a
given PS block length, longer PEO blocks were more likely to produce
intercalation. In general, the increased gallery spacings were close to
those produced by modifying montmorillonite with PEO homopolymer.