Amorphous phases generated by pharmaceutical processes lead to cocrystal formation under conditions where there is increased molecular mobility and complementarity. Water, a potent plasticizer, enhances the rate of cocrystallization. This has powerful implications to control process induced transformations.

Low density polyethylene (LDPE)/clay nanocomposites, which can be used in packaging industries, were prepared by melt-mix organoclay with polymer matrix (LDPE) and compatibilizer, polyethylene grafted maleic anhydride (PEMA). The pristine clay was first modified with alkylammonium salt surfactant, before meltmixed in twin screw extruder attached to blown-film set. D-spacing of clay and thermal behavior of nanocomposites were characterized by Wide-Angle X-ray Diffraction (WAXD) and differential scanning calorimetry (DSC), respectively. WAXD pattern confirmed the increase in PEMA contents exhibited better dispersion of clay in nanocomposites. Moreover, DSC was reported the increased PEMA contents caused the decrease in degree of crystallinity. Mechanical properties of blown film specimens were tested in two directions of tensile tests: in transverse tests (TD tests) and in machine direction tests (MD tests). Tensile modulus and tensile strength at yield were improved when clay contents increased because of the reinforcing behavior of clay on both TD and MD tests. Tensile modulus of 7 wt % of clay in nanocomposite was 100% increasing from neat LDPE in TD tests and 17% increasing in MD tests. However, elongation at yield decreased when increased in clay loading. Oxygen permeability tests of LDPE/clay nanocomposites also decreased by 24% as the clay content increased to 7 wt %.

Time-resolved light scattering demonstrates that the early-stage quiescent and flow-induced crystallization kinetics of an intercalated polypropylene clay nanocomposite differs significantly from that of pure polypropylene. The material studied is organophilic montmorillonite clay dispersed at 2.0 wt % by melt mixing in an isotactic polypropylene matrix with maleic anhydride functionalized polypropylene compatibilizer. Characteristic crystallization times are extracted from the time evolution of integral measures of the angularly dependent parallel polarized and cross polarized light scattering intensity. For quiescent isothermal crystallization with undercooling ∆T < 32 °C, measured relative to its melting temperature, the compatibilized, intercalated nanocomposite displays retarded crystallization kinetics compared to that of pure polypropylene. However, the nanocomposite behavior does not differ significantly from that of a polypropylene/maleic anhydride functionalized polypropylene blend within the temperature range for which the characteristic crystallization times of the latter material could be extracted. Debye-Bueche analysis of the polarized light scattering intensity demonstrates significant differences in the time-dependent growth of isotropic morphology in the polymer and the nanocomposite. Marked flow-induced acceleration of crystallization kinetics is observed for the polymer nanocomposite at applied strain rates for which flow has only a modest effect on polypropylene crystallization. By comparing this behavior to that of a blend of polypropylene and compatibilizer, we infer a significant role for the latter species in flow-induced nanocomposite crystallization. We furthermore find that the magnitude of the flow-induced acceleration of crystallization for the polypropylene nanocomposite is a unique function of the applied strain.