Antiblocking additives

Blocking is the adhesion of two adjacent layers of film and is a common problem encountered by manufacturers of polyolefin films and coatings.
The blocking between adjacent layers results in increased friction and the addition of an antiblocking agent generally contributes to a reduction in the film-to-film coefficient of friction.
Natural silicas obtained from sedimentary rocks have always been used as antiblocking agents, due to their structure similar to a microscopic sponge, which can increase the formation of micro-wrinkling on the film, thus reducing the points of contact and giving a perfect detaching effect.
However, natural silica performs a lower antiblocking effect if compared to synthetic silica and also shows impurities. For these reasons the synthetic version is preferred.
Viba laboratories developed two antiblocking additives: Vibatan PE Antiblocking 03946 and Vibatan PE Antiblocking 04251, suitable for the extrusion of polyolefin films, even of those having a minimum thickness.
Both are suitable to replace masterbatches containing natural silica which may cause unpleasant effects, such as the reduction of optical properties or the excessive absorption of co-additives, thus limiting their performance.
They avoid such inconveniences, drastically reducing the points of contact and giving a perfect detaching effect at lower dosaged if compared to masterbatches having natural silica.
These Viba products are suitable for food packaging.