Question to ask

Does PMMA Thermoplastic Resin have a anti skid surface ? :smiley:
What is Blasted Post Mold ?

It “has” whatever surface texture is applied to the mold in which it is formed.

Think of thermoplastics (materials that will melt (and can be re-melted)) as water … no inherent surface-texture, or color. Surface is determined by applying a texture to the mold surface(s). Color is obtained by adding colorants or tints.

“Blasted Post Mold” probably refers to a process whereby the molded part is subjected to media-blasting (basically sand blasting with a “softer” material than sand) to obtain a matte finish, or to remove flash, etc.

PMMA is acrylic. We’ve never looked at acrylic to have high frictional properties. We’ve only ever used it for its optical properties or a need for translucency. For Acrylic (aka Plexiglas®) there aren’t any properties listed regarding it’s “tack and grip” but you’d be able to play with that via texture - if you really want a plastic providing surface friction try to find a sample used on another product and then analyze what it is. See the published properties from the world leader of PMMA; Altuglas International of Arkema, Inc. at PMMA – Americas

Blasted Post Mold - without any other details on that question, it sounds like someone is taking a part and blasting it with a media after its been molded. The reasons might be to give a part a certain texture AND low gloss effect. The blasting will change the surface tension on the plastic and also allow it to be painted. To prep a plastic part for painting, an alternate for blasting would be flame treating the plastic part which could be done much faster, more consistently and provide more uniform results per part.

Does it have a non skid surface? I would say no. PMMA is a hard material, is is not the rubbery material I associate with non-skid descriptions in products. Texturizing it will reduce the surface area and potentially make it slipperier on footpads for example.

I have flame treated lots of plastics for adhesion promotion and experimented with corona treatments, I have not used any blasting for paint adhesion, assuming that it only worked for metals. What plastics and what blasting medias are used?

Regarding surface tension, “Dyne markers” are a great thing to see the invisible.

So JB, what are you making out of acrylic that needs to be anti-slip? It’s not exactly a “strong” material by itself…

One of our engineers is providing this knowledge, feel free to contact me if our services might add value to your projects; Flame or corona treating is the way to go…but if you don’t have a flame handy or an electrostatic machine handy to generate the Corona then an alternative would be to blast it. The cost and time associated with blasting a part far exceeds the previous mentioned methods. Any media can be used but you would need to experiment with the pressures and the media size depending on the part size that you’re trying to paint and any intricacies involved with the geometry. A flame can get everywhere but the blasting particles need to be directed to each of the crevices to work properly.

When evaluating whether or not the surface was prepped properly for paint, do a simple water bead test - if water beads up on the surface tension is still too high but if it spreads out the surface tension is appropriate for the paint to adhere. Whether it’s blasting corona treating or flame treating the process is all about changing the surface tension of the plastic.

Thanks guys for your help.
Appreciate all the info you have given :slight_smile: