Some of them do. Rigid PVC and polycarbonate sheets are practically opaque to UV radiation, making them a perfect barrier against this harmful radiation. They actually block UV-A and UV-B radiation better than nearly any sunscreen lotion.
On the other hand, acrylic roofing sheets (which are not produced by Palram) generally transmit a considerable portion of the UV radiation.
Review the technical datasheet for each Palram product for specific UV information.