Mechanical Properties and Flame Retardancy of Sawdust/Recycled High Density Polyethylene Composites: Effects of Alkali Treatment and Flame Retardant



Sawdust/recycled high density polyethylene (rHDPE) composites were prepared at a sawdust content of 30 wt% using a twin screw extruder. Effects of alkali treatment and flame retardants; ammonium polyphosphate (APP), aluminum trihydrate (ATH) and zinc borate (ZB) on mechanical, flame retarding and morphological properties of the rHDPE composites were investigated. The alkali treatment led to enhanced mechanical properties and flame retardancy of the composite. Tensile strength, elongation at break and impact strength of the composites were decreased with the addition of flame retardants while tensile modulus and flame retarding properties were increased. Among the flame retardants, APP exhibited the most effective improvement of flame retardancy of the composite. Moreover, the mechanical and flame retarding properties of the composite were improved in the presence of maleic anhydride grafted polyethylene.


Recycled HDPE, sawdust, flame retardants, alkali treatment, compatibility

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Last updated: 20 June 2019