Structural properties, evolution of morphology and crystallization kinetics in immiscible polymer blends filled with multiwall carbon nanotubes (MWNTs) in the droplet phase were systematically investigated in this study. By grafting suitable macromolecules (here SAN, styrene acrylonitrile), that can drive the MWNTs to the droplet phase, allowed the understanding of the rate of nucleation and growth of the semicrystalline matrix in droplet-filled blends in contrast to matrix-filled blends. By blending 90 wt% of PVDF with 10 wt% ABS, matrix-droplet morphologies were generated and by grafting SAN onto MWNTs, the localization of the nanotubes was tuned to fill the droplet phase which otherwise prefers the matrix phase (here PVDF); driven by thermodynamics. The evolution of morphology under quiescent annealing conditions was assessed by SEM. The blends with SAN-g-MWNTs also coarsened as a function of time similar to neat blends however, to a lesser extent. Although, droplet laden MWNTs did not suppress coarsening in the blends but it still improved the tensile properties when compared with the neat blends. The fold surface free energy (as evaluated from isothermal crystallization kinetics) was estimated to be less in case of blends with only MWNTs in contrast to blends with SAN-g-MWNTs. This was attributed to the fact that matrix (here PVDF) filled with MWNTs experiences faster crystallization rate due to heterogeneous dispersion of nucleating agents (here MWNTs) in the matrix. However, when the SAN-g-MWNTs were mostly localized in the amorphous droplet phase (here ABS), PVDF experienced similar crystallization behavior like the neat PVDF/ABS blends. Taken together, our study demonstrates that lower amount of energy is required for the arrangement of PVDF chains into the crystal lattice upon cooling from the melt state and accelerate the crystallization process when the heteronucleating agents are localized in the matrix phase than when they are localized in the amorphous droplet phase.

在本研究中，系统研究了液滴相中充满多壁碳纳米管（MWNT）的不混溶聚合物共混物的结构特性，形貌演变和结晶动力学。通过接枝可以驱动MWNTs进入液滴相的合适的大分子（此处为SAN，苯乙烯丙烯腈），可以了解液滴填充的混合物中与基质填充的混合物相比，半结晶基质的成核速率和生长速度。通过将90 wt％的PVDF与10 wt％的ABS混合，生成基质-液滴形态，并将SAN接枝到MWNT上，调整纳米管的位置以填充液滴相，否则液滴相将更喜欢基质相（此处为PVDF）；由热力学驱动。通过SEM评估了静态退火条件下的形貌演变。g -MWNTs也随时间而变粗，类似于纯净的混合物，但程度较小。尽管含液滴的MWNTs不能抑制共混物中的粗化，但与纯共混物相比仍能改善拉伸性能。与仅具有SAN- g- MWNT的混合物相比，仅具有MWNT的混合物的折叠表面自由能（通过等温结晶动力学评估）估计较少。这归因于以下事实：由于成核剂（此处为MWNT）在基体中的不均匀分散，充满MWNT的基体（此处为PVDF）经历了更快的结晶速度。但是，当SAN- g-MWNTs大多位于非晶液滴相（此处为ABS）中，PVDF经历了相似的结晶行为，如纯PVDF / ABS共混物。综上所述，我们的研究表明，将杂化剂定位在基体相中时，从熔体态冷却后，PVDF链在晶格中排列所需的能量更低，并加速了结晶过程。无定形液滴相。