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• Tailored interfacial entanglement in PLA/POE was constructed via reactive blending. • POE domains were embedded tightly in PLA with abundant interface transition area. • Due to enhanced molecular entanglement, PLA/POE showed strain-hardening behavior. • Uniform and effectively toughened PLA/POE films with low POE content were prepared. • Impact fractured surface shows plastic deformation and less interfacial de-bonding. In order to obtain a uniform and effectively toughened poly (lactic acid) film by blending with low content of poly (ethylene octene) (POE) with high elasticity, the tailored interfacial intermolecular interaction and entanglement between the two phases of the PLA/POE blend was innovatively constructed via the facile reactive melt blending process through the reaction of the epoxy/anhydride groups grafted on the POE chains with the end groups of PLA chains (PLA/GPOE-MPOE). It was observed that POE domains were embedded tightly in PLA matrix with a fuzzy interface and abundant interface transition area, and the impact fractured surface of the blend showed an obvious plastic deformation with less occurrence of fibrillation of PLA matrix or interfacial de-bonding. Compared with neat PLA and directly blended PLA/POE blends, the PLA/GPOE-MPOE blend exhibited much higher complex viscosity/storage modulus, much lower tan δ values in the terminal region, and obvious strain-hardening behavior. The deviation in viscoelastic behavior of PLA/GPOE-MPOE from linear PLA indicated the enhanced molecular entanglement between the long-branched chains, resulting in an enhancement of the stretching ability during biaxial drawing of the blend. Uniform PLA/GPOE-MPOE films with draw ratio as high as 7 × 7 were obtained through biaxial stretching, which showed much higher tensile strength and the elongation at break than that of neat PLA and PLA/POE film. This work provides a facile method for fabricating toughening PLA films with application potentials. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: In this report, hexakis (4-nitrophenoxy) cyclotriphosphazene (HNCP) and ethylene–octene copolymer grafted-maleic anhydride (POE-g-MA) were blended with pure PET together. The fire retardant ability and thermal stability of PET/HNCP/POE-g-MA were investigated respectively. The results indicated that HNCP and POE-g-MA had a synergic effect on the dripping resistance of PET besides the enhancement in flame retardancy to a certain degree. LOI values of the polymers with both POE-g-MA and 10wt%HNCP were higher than that of pure PET and no drips just containing 1wt%POE-g-MA. The reason was that HNCP could be well dispersed in PET when POE-g-MA was added, forming a more effective char layer and preventing dripping of polymers. Indeed, the morphology of charred residue of PET/HNCP/POE-g-MA showed that a porous protective layer with a dense surface was formed. The thermogravimetric analysis revealed that addition of HNCP improved the thermal stability and the yield of char residue of the PET/POE-g-MA systems. Based on a series of experiment results, the synergistic effect of HNCP and POE-g-MA on the anti-dripping of PET was also discussed. In the PET/HNCP/POE-g-MA system, POE-g-MA played a role of compatibilizer. The improved compatibility and dispersion provided the composite with the ideal flame retardancy, thermal stability and anti-dripping property. [Copyright &y& Elsevier]