Raw PVC is not enough to meet the needs of modern infrastructure. It is only when stabilisers and UV absorbers, along with other impact modifiers, are added that PVC pipes become more reliable. These additives almost behave like an invisible armour that is shielding the pipe from high temperatures, destructive UV radiation, cracking, or rust and corrosion. Flame-retardant additives in... https://blogosm.com/pvc-pipe-performance