In a recent conversation with a specialist at Golden paints, I was told that Yupo has done poorly in testing with acrylic paint, which adhered to the paper poorly.
I've contacted Yupo directly, but haven't heard back yet. Do you have any information about this issue?
Thanks.

Polymer on polymer (or polypropylene) may not be the best match, but thousands of artists ignore that and continue to be very excited and pleased with the work they can create painting with acrylic on YUPO. Generally, acrylic will not come off YUPO, although thick applications can be scraped off with a fingernail or a knife. Acrylic paint will not be disturbed by normal handling, and acrylic/YUPO pieces may be framed without glass or matting. If preferred, glass/matting is acceptable and provides extra protection to the painting.

Acrylics can be easier to control on YUPO than watercolor. They do not run as fast. If it is not sticking enough, a small amount of liquid soap may be added. Grease or oil from fingerprints or other sources may impair adhesion. To remove, wash YUPO with soapy water, rinse, and allow to dry. Water does not affect YUPO.

Layering of acrylics is aided by the use of a gel medium, making adhesion between layers and the YUPO even stronger. Paint colors are more vivid on YUPO because the paint never soaks into the paper. Fluid acrylics are especially popular on YUPO. While wet, the paint can be easily removed, which can be either a great benefit or a disappointing feature. It is up to artist.

YUPO does not need to be stretched and will not buckle with use of water. Caution should be used with using hair dryers to speed drying. Buckles may remain after heat is applied.

YUPO is an acid-free synthetic made from 100% polypropylene. It is an inert and chemically stable product which requires no buffering. Bi-axially Oriented Polypropylene (BOPP) has excellent clarity, low electrostatic charge, and is safe for long-term storage.