Most PVC pipe has some UV inhibitor added (TiO2 I believe), but over time the pipe will become chalky on the outside and more brittle. jte and moltenmetal are correct, use latex paint, not solvent based paint. If this is an existing line (already weatherd), you may have trouble getting the paint to bond well to the pipe, causing an ongoing maintenance headache! Depending on the "corrosive material" involved, you may be able to use FRP, or lined steel.
You may want to consider other materials with your high ambient temperature in the summer. 115 Deg outside means the surface of the pipe is likely much higher. PVC has a maximum service temp of 140 and loses much of its strength and pressure capability at that temp. CPVC will be better as it is rated to around 200 deg F.
Lastly, make sure you compensate for expansion and contraction in the PVC or CPVC line. With large temperature swings, it can be considerable compared with metal or FRP.