Glass fibre composites were recycled by microwave pyrolysis. The glass fibres recovered were evaluated as a reinforcement agent for polypropylene (PP). Samples were prepared with a micro-compounder and the resulting compounds were evaluated with tensile testing, flexural testing, Charpy impact testing and scanning electron microscopy (SEM). The adhesion between fibre and glass was relatively poor, and an attempt was made to improve it. Various coupling agents were evaluated, in addition to the use of maleic anhydride-grafted PP (MA-PP). Tests showed that MA-PP had a relatively strong effect on the mechanical properties.