Fabrication of self‐reinforced polyester composites and their mechanical and flame retardant properties

Self‐reinforced polyester composites (SRPCs) with light weight, high mechanical properties, good interfacial bonding, and easy to recycle at the end after use have been developed to replace traditional synthetic fiber‐reinforced plastics. This study is on fabrication of SRPCs is performed using polyethylene terephthalate (PET) as matrix and polybutylene terephthalate (PBT) as reinforcement material through compression molding via film stacking method. The compression molding parameters such as temperature, pressure, and dwell time were optimized by Taguchi method, and these values are 225°C, 8 MPa, 5 min for tensile strength, 225°C, 5 MPa, 15 min for flexural, and 215°C, 3 MPa, 5 min for impact test. Flame retardancy in SRPCs has also been introduced as a new idea to minimize the flammability nature and is helpful in engineering applications. Flame retardants (FRs) such as ammonium polyphosphate (APP), zinc borate (Zb), and magnesium hydroxide (Mg(OH)2) were used. The flame retardancy mechanism of optimized SRPCs works effectively which was evident by horizontal burning and LOI test. Thermogravimetric analysis (TGA) was also studied to confirm the thermal properties of the composites. Mechanical properties were reasonably affected by the FRs as confirmed by field emission scanning electron microscope (FESEM).