Well dispersion of poly(acrylonitrile‐butadiene‐styrene) in isotactic polypropylene mediated by incorporation of graphene and the elevated toughness

Abstract

Polymers with benzene rings in structures including polystyrene (PS) and poly(acrylonitrile‐butadiene‐styrene) (ABS) could function as rigid organic particles and macromolecular β nucleating agents to toughen isotactic polypropylene (iPP), and the toughening effect mainly depends on their dispersibility in iPP matrix. In this work, a third component of graphene (G) was introduced into the iPP/PS and iPP/ABS blends, respectively, to mediate the dispersibility of these polymers in the iPP via melt blending. Selective dispersion of graphene in these immiscible blends has been investigated with SEM, DSC, and a rheometer. It was interesting to obtain a more favorable dispersion of ABS in the iPP/ABS/G blend compared with the iPP/ABS blend, and the corresponding toughness showed a prominent improvement accompanied with an elevation in rigidity. The underlying mechanism for the improved dispersion of ABS in the iPP/ABS/G blends has been discussed in detail. However, because of a better affinity of the graphene to the PS than the iPP matrix, graphene could only locate in the PS phase, resulting in poor compatibilization for the iPP/PS blend followed by the deterioration of mechanical properties.

Annealing induced high‐impact toughness of injection molded isotactic polypropylene filled with liquid‐phase exfoliated graphene

“…[1][2][3] To solve this major drawback, considerable work on toughening modification of iPP has been carried out. Of which, a variety of additives had been incorporated into iPP during the melt blending process, such as β nucleating agent, [4][5][6][7][8][9][10][11][12][13] rigid particles, [14][15][16][17][18][19][20][21][22][23] and elastomer. [24][25][26][27][28][29] These second components could induce the formation of loose β-crystal structure in iPP matrix, or trigger massive craze or shear banding under the impact load condition, which are favorable for the improvement of iPP toughness.…”

Annealing‐induced high impact toughness of immiscible isotactic polypropylene/poly(acrylonitrile‐butadiene‐styrene) blend

“…Since Kurauchi and Ohta 33 investigated the energy absorption in incompatible blends consisting of a brittle polymer as a dispersed phase and a ductile matrix, and proposed so‐called cold drawing toughening mechanism, toughening iPP by adding rigid particles has been explored extensively and proved to be a promising approach to achieve a satisfactory rigidity‐toughness balance. In general, rigid particles (including organic rigid particles and inorganic rigid particles) could debond and cavitate at the interface under the impact load condition, accompanied with the release of high plastic constraint in iPP matrix 20–29 …”

“…[1][2][3] The most convenient toughening strategy is melt blended with some modifiers, such as β nucleating agent, [4][5][6][7][8][9][10][11][12][13] elastomer, [14][15][16][17][18][19] and rigid particles. [20][21][22][23][24][25][26][27][28][29] It should be pointed out that the incorporation of β nucleating agent inevitably brings about a decrease in the rigidity of iPP resulting from loose lamellae arrangement in β-crystal. [30][31][32] Similarly, relatively low modulus and strength of elastomer is also a critical obstacle for the improvement of iPP toughness without the expense of stiffness and strength.…”

“…In general, rigid particles (including organic rigid particles and inorganic rigid particles) could debond and cavitate at the interface under the impact load condition, accompanied with the release of high plastic constraint in iPP matrix. [20][21][22][23][24][25][26][27][28][29] As another important commercial thermoplastic, acrylonitrilebutadiene-styrene graft copolymer (ABS) resin is a typical two-phase structure material, consisting of styrene-acrylonitrile copolymer as matrix and polybutadiene as dispersed phase. Tan et al found that ABS is a suitable candidate to improve the foamability of iPP.…”

“…However, poor impact toughness limits its application fields 1–3 . The most convenient toughening strategy is melt blended with some modifiers, such as β nucleating agent, 4–13 elastomer, 14–19 and rigid particles 20–29 . It should be pointed out that the incorporation of β nucleating agent inevitably brings about a decrease in the rigidity of iPP resulting from loose lamellae arrangement in β‐crystal 30–32 .…”