PDF articles are downloaded from the publisher sites. Once you have found the desired article on the publisher site, you may click on the “Download PDF” option available there, which downloads the PDF article into MyLOFT.
For iOS devices, the PDF articles are rendered first. After that click on the 
(Save) button at the bottom right of the browser to download the PDF article into MyLOFT.
Note: PDF articles are downloaded on the device and only the URL of the PDFs get synced across the device.