Evaluation of reused polyester resin from PET bottles for application as a potential barrier material

Resin systems containing reused polyethylene terephthalate (PET) in their composition were evaluated, as well as the influence of montmorillonite and dolomite for application in plugging and abandonment (P&A) and remedial operations as an alternative material to conventional cementing. The resin compositions were characterized using infrared, with characteristic bands of polyester and styrene monomers being identified in all systems, even with the addition of the thixotropic agent and mineral filler. Compressive strength (CS), rheology, and stability under sedimentation tests were performed. The pure polyester resin showed a CS value above 90 MPa for all curing times. This result is 12 times higher than the minimum required for abandonment operations (7 MPa). All systems presented Newtonian behavior and the addition of 5% dolomite decreased the apparent viscosity. The optimum systems was formulated with 0.1 montmorillonite and 5% dolomite. Based on the results presented, with high compressive strength and low viscosity, the polyester resin proved to be promising for application in well cementing to P&A and remedial operations.