HYBRID POLYMER COMPOSITE BASED ON RECYCLED POLYETHYLENE TEREPHTHALATE REINFORCED WITH FUNCTIONALIZED NATURAL FIBRES

The invention relates to a process for preparing a hybrid polymer composite based on recycled polyethylene terephthalate reinforced with functionalized natural fibres to be used for manufacturing products workable in injection moulds. According to the invention, the process consists in pre-mixing, in a mixer, 87...97 parts by weight of recycled polyethylene terephthalate (PET) as grains, 1...5 parts of polyethylene based waxes, as compared with the amount of fibers, 2...10 parts of short flax fibers functionalized with 1...5 parts of titanium butoxide or isopropoxide and 1...5 parts of a volatile-adsorption agent CaO as related to the amount of PET, at a speed of 475...950 rpm, resulting in grains/films with densities higher than 1 g/cm, the premix is dried at a temperature of 140°C and is discharged in a primary dosing system, followed by compounding the mixture in a twin screw extruder-granulator, sudden cooling in water bath, drying with hot air and granulation, resulting in a composite as grains.