Additives: Scratch/Mar Resistance for PMMA

A new anti-scratch additive for PMMA, said to deliver superior scratch/mar resistance while minimizing any negative effects on optical properties, is newly available from TenasiTech (U.S. office in Boston). Solid-FS is the company’s second patented organoclay with special organic surface treatment that helps maximize the disassociation of the clays when compounded into thermoplastics (see Dec. ’16 feature), and offers an affordable alternative to hard coating.

The first product, Solid-TT, has received good commercial acceptance in PMMA and nylon 6, and looks promising for PET and PVC/PMMA compounds. According to CEO Richard Marshall, the new Solid-FS grade sports both a different surface treatment and different particle size (much smaller agglomerates), and is ideal for high-gloss applications. Moreover, Solid-FS is effective in PMMA at much lower addition rates—0.25% vs. 1% for Solid-TT.

The additive has been shown to deliver up to 7H pencil hardness, compared with 3H for virgin PMMA. Resulting compounds boast superior optical properties, with only 5% haze and a drop of only 2% in gloss. The additive reportedly does not adversely affect other key properties such as impact strength, elastic modulus or resistance to weathering. Moreover, it cannot be rubbed off, and the final product can be thermoformed. No secondary hard-coating steps are needed.