A comprehensive review on chemical route to convert waste cooking oils to renewable polymeric materials

A large proportion of waste cooking oil (WCO) is currently being generated worldwide, which has led to crucial problems in its waste management due to absence of a proper disposal procedure. Most scholars mainly spotlight on the biodiesel production from WCO as alternative, despite the fact that there are other applications that require attention. Although WCO do not exist as polymers in nature, they are precursors for monomer chains which contain beneficial functional group to act as reactant. Triglycerides, which result from the esterification of glycerol with three fatty acids, are the major components of WCO. These triglycerides have a number of reactive sites, including ester groups and double bonds, providing a variety of opportunities for chemical modification, then polymerize to produce high molecular weight hydrocarbons. This review paper highlights the chemical processes required to produce polyurethane (PU), epoxy, polyhydroxyalkanoates (PHAS), acrylic, and alkyd resins polymers from WCO. The reaction initiator, catalyst, crosslinker, and others reagent used for the reaction process to convert into different functional monomer were summarized. As a result, WCO can be considered as a potential waste that can be used as a renewable polymer precursor to replace those are currently derived from petroleum hydrocarbons.