Nanocomposites Based on End-Functionalized Polystyrene

Nanocomposites based on isotactic polypropylene (i-PP) end-functionaUzed with an ammonium group, PP-t-NH3+ were reported by Wang et al. [71]. Specifically, they used PP-t-NH3+ to melt intercalate, under static conditions, both MMT and dioctadecylammonium-modifled MMT (2C18-MMT) to yield PP-t-NH3+Cl /Na+MMT and PP-t-NH3+Cr/2C18-MMT nanocomposites, respectively. Wang et al. observed featureless XRD patterns for both of these nanocomposites, which led them to speculate that exfoliated clay structures had formed, possibly by an ion-exchange mechanism. However, proof of the speculated ion-exchange mechanism was not provided. 

Polystyrene-block-Polyisoprene (SI Diblock) Copolymer or Polyisoprene-block-Polystyrene (IS Diblock) Copolymer 

Ion-Dipole Interactions in Exfoliated Nanocomposites Based on Polystyrene-A/oc -Poly(2-vinylpyridine) Copolymer Prepared by Mixing 

In this section we present the recent study of Zha et al. [7], who prepared organoclay nanocomposites based on polystyrene- tocfc-poly(2-vinylpyridine) (S2VP diblock) 

We observe from Fig. 41b that the XRD pattern of (S2VP-25)/MMT nanocomposite shows a conspicuous reflection peak at 29 6° (d-spacing = 1.5nm), suggesting poor dispersion of MMT aggregates in the S2VP-25 matrix, although some 

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Rheology of Organoclay Nanocomposites Based on End-Functionalized Polystyrene... 

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