The major material used for eco pvc fence panels is UPVC
Unplasticized polyvinyl chloride (uPVC) or rigid PVC is extensively used in the building and construction industry . It has a wide selection of applications from double glazing and uPVC conservatories to fencing. This kind of material is very robust and is known as low-maintenance which means it is resistant to chemicals, sunlight and water damage. With a variety of colors and finishes uPVC is produced with a lot of variety like finished photo effects . Cast iron which was traditionally used for plumbing and drainage for drainpipes, gutters, downspouts and wastepipes has been almost entirely replaced by uPVC.
I prefer to call PVC as Polymer with Versatile Characteristics based on its availability, flexibility in terms of getting different types of products through compounding from the same PVC and processability on any type of equipment. This makes it a very versatile plastic, besides it is cheap.
PVC has engineering properties too that finds its use in pipes, profiles, and in construction.