Self‐nucleation behaviors of olefinic blocky copolymer/montmorillonite nanocomposites with collapsed and intercalated clay layers

Abstract

ABSTRACTThe self‐nucleation behavior of olefinic blocky copolymer (OBC) / organically modified montmorillonite (OMMT) nanocomposites with a novel collapsed clay structure (c‐OMMT) was studied and compared with that of the nanocomposites with an intercalated clay structure (OBC/i‐OMMT). Their behaviors appear different in three temperature domains, Domain I (DI) in which the polymer is completely melted and only the heterogeneous nuclei are present, Domain II (DII) in which only self‐nucleation occurs and Domain III (DIII) where both self‐nucleation and annealing take place. As the OMMT loading increases, the boundary temperature of DI and DII (TI→II) shifts to lower temperature and DII becomes narrower. For the OBC/c‐OMMT nanocomposites, the TI→II or TI→III (the boundary temperature of DI and DIII) can be lower than the end melting temperature ( ) and leads to appearance of a subdomain of DI, DI′, in which the self‐nuclei of un‐melted fragmental crystals exist but the following crystallization is still initiated by c‐OMMT. DII may even disappear at high c‐OMMT loadings. By contrast, the TI→II of the OBC/i‐OMMT nanocomposites is always approximate to or higher than the . DII does not disappear and no DI′ is observed for the OBC/i‐OMMT nanocomposites. The nucleation efficiency of c‐OMMT is also evidently higher than that of i‐OMMT. These results verify that the c‐OMMT has stronger nucleation ability than i‐OMMT at the same OMMT loading. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41771.