Effect of microcapsulated red phosphorus on flame retardant, thermal and mechanical properties of thermoplastic polyurethane composites filled with huntite&hydromagnesite mineral

The effect of microcapsulated red phosphorus (mRP) was studied on the flame retardant, thermal and mechanical properties of thermoplastic polyurethane (TPU) composites containing Huntite&hydromagnesite (HH). The flame retardant properties of TPU based composites were investigated using limiting oxygen index (LOI), vertical burning test (UL 94), thermogravimetric analysis (TGA) and mass loss calorimeter. The mechanical properties of composites were studied using tensile test and dynamic mechanical analysis (DMA). According to the test results, the adjuvant effect of mRP was observed in terms of both flammability and mechanical properties of composites. The highest LOI value (32.5), the highest UL-94 rating (VO) and the lowest pHRR (155 kW/m(2)) value were observed with the partial substitution of 7 wt% mRP with HH. The tensile strength also increased at about 60% with respect to TPU/50HH. The mRP showed the synergistic effect by increasing the barrier effect of residue in the condensed phase and the formation of active radicals in the gas phase. The mRP showed adjuvant effect on mechanical properties due to the plasticizing and compatibilizer effect of low molecular weight epoxy resin carrier. (C) 2016 Elsevier Ltd. All rights reserved

Effect of reactive and nonreactive surface modifications and compatibilizer use on mechanical and flame-retardant properties of linear low-density polyethylene filled with huntite and hydromagnesite mineral

In the current study, huntite and hydromagnesite (HH) was used as flame-retardant additive in linear low-density polyethylene (LLDPE). The effect of HH amount on the flame-retardant and mechanical properties of the composites was investigated. The compatibilizer (ethylene butyl acrylate) use and the surface modifications with stearic acid and silane coupling agent were used in order to improve the mechanical properties of the composites. The mechanical properties of the composites were studied using tensile test and dynamic mechanical analysis. The fire-retardant properties of the composites were investigated using limiting oxygen index (LOI), mass loss calorimeter, vertical (UL 94V) and horizontal (UL 94 HB) burning tests. According to the flammability test results, LOI value increased, horizontal burning rate reduced as the added amount of HH increased, whereas UL 94V rating remained burn to clamp. According to the mechanical test results, the addition of HH reduced the tensile strength and elongation at break values and increased the elastic modulus and the transition temperature of the LLDPE as the added amount increased. Only the compatibilizer use improved the flammability properties of the composites with improved tensile strength. Both stearic acid and silane modification merely increased the toughness of the composites