Ceramifiable flame-retardant ethylene-vinyl acetate (EVA) copolymer composites for wire and cable sheathing materials were prepared through melt compounding with ammonium polyphosphate (APP), aluminum hydroxide (ATH) and fluorophlogopite mica as the addition agents. The effects of ammonium polyphosphate, alumina trihydrate, and APP/ATH hybrid on the flame retardant, as well as on the thermal and ceramifiable properties of EVA composites, were investigated. The results demonstrated that the composites with the ratio of APP:ATH = 1:1 displayed the best flame retardancy and the greatest char residues among the various EVA composites. The tensile strength of the composites was 6.8 MPa, and the residue strength sintered at 1000 °C reached 5.2 MPa. The effect of sintering temperature on the ceramifiable properties, microstructures, and crystalline phases of the sintered specimen was subsequently investigated through X-ray diffraction, Fourier transform infrared, and scanning electron microscopy. The XRD and FTIR results demonstrated that the crystal structure of mica was disintegrated, while magnesium orthophosphate (Mg3(PO4)2) was simultaneously produced at an elevated temperature, indicating that the ceramization of EVA composites had occurred. The SEM results demonstrated that a more continuous and compact microstructure was produced with the rise in the sintering temperature. This contributed to the flexural strength improvement of the ceramics.

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The structure and property of cassava starch-based films, produced by using 1-butyl-3methylimidazolium chloride ([BMIM]Cl) and glycerol as combined plasticizers, were investigated. The combined plasticizers exhibited a stronger effect on the disruption of starch granules compared with glycerol as observed by scanning electron microscopy (SEM). When the mass ratio of [BMIM]Cl/glycerol used was 15/15, all the starch granules were disrupted and transferred to a continuous phase. Due to the strong plasticization effect of [BMIM]Cl, the combined plasticizers contributed to a lower water content, crystallinity, and glass-transition temperature, as well as a higher flexibility when compared with glycerol. Additionally, in spite of the slight decrease in the elongation at break, the combined plasticizers contributed to a higher thermal stability, higher tensile strength, and a lower cost relative to [BMIM]Cl alone, showing excellent potential for practical applications. Therefore, using [BMIM]Cl and glycerol as combined plasticizers to plasticize starch film is effective, practical, and economical, and opens up a new perspective for the plasticization of starch.

A novel ceramifying silicone rubber composite filled with mica powder, glass dust and glass fiber was prepared for high-temperature applications.