engleski

Lamellar block copolymers as viewed by deuterium NMR spectroscopy

Oriantational dynamics of the chain segments in a lamellar structure of block copolymer was studied by deuterium NMR spectroscopy. Polystyrene-polybutadiene diblock (PS-PB) and polystyrene-polybutadiene-polystyrene triblock (PS-PB-PS) were studied by the use of short perdeuterated PB chains (NMR probes). The results show an uniaxial character of the chain dynamics. This effect is more pronounced in PS-PB-PS, because of possible different chain conformations. The orientational dynamics of probe chains in PS-PB is compared with that observed in PS-PB having perdeuterated PB block. The segmental dynamics of a semicrystalline polystyrene-polydimethylsiloxane (PS-PDMS) was investigated by the use of deuterated octane (C8D18).

block copolymer; lamellar; orientation; NMR

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