Influence of modified polyethylene compatibilizer on filler dispersion and flammability characteristics of linear low density polyethylene/cyclo olefin copolymer blends containing flame retardant combinations

In this study, the combination of organomodified montmorillonite (MMT), magnesium hydroxide (MDH), graphene oxide (GO) and expandable graphite (EG) as intumescent flame retardant for Linear Low-Density Polyethylene-Cyclo-Olefin Copolymer (LLDPE/COC) blends has been investigated. An amine-alcohol modified polyethylene (PEgDMAE) was used as compatibilizer. Limiting oxygen index (LOI), cone calorimeter determinations and flammability test (Underwriters Laboratory – UL-94) were used to evaluate the flame retardant properties. The structural characterization was measured by FTIR and scanning electron microscopy (SEM). The mechanical properties were also evaluated by Dynamic-mechanical analysis (DMA). The PEgDMAE compatibilizer enhanced the filler dispersion and increased the LOI to 22% for clay, 23% for GO and 26.5% for EG composites. The results indicated that the combination of each additive makes it possible to reduce the total Magnesium hydroxide filler content from 55 to 20% to achieve the flame retardant requirements. The flame retardant and mechanical properties of LLDPE/COC blends increased to a higher extent when using the combination of these additive fillers.