In manufacturing and processing plastic applications, it usually occurs blocking situation. Which is the adhesion between polymer film layers, that complicates the separating of them. In this case, plastic producers prefer to use Anti-blocking Additive.
Anti-blocking is a term used to describe measures to prevent film sheets to stick together. Polyolefin films tend to adhere to each other due to strong van der Waals interaction or electrostatic charges .When being in close contact (adjacent layers). The higher the temperature, pressure, and contact/processing time, the higher the tendency to stick to each other. Anti-blocking additives prevent blocking and tackling with the production and further processing of films, coatings, as well as coextrusion layers. This additive creates an even micro-rough surface .Which reduces the direct contact surfaces and acts the as the spacer between the film surfaces.
Fillplas’s Anti-blocking Additive
At FILLPLAS, our anti-blocking additives take advantage of reducing blocking at the surface of polymer films. And other plastic articles in order to allow easier processing and handling as preventing the ability of adhesion of surfaces. By the development of the technology of manufacturing, our anti-blocking additive ensures higher film clarity with lower usage levels. Even though with the high temperature, pressure, and processing period. The assistance of our anti-blocking additives will prevent the ability of sticking together of your films as well as your products.
To avoid the adherence of layers due to a close contact, particulate matter is introduced into the film in a highly diluted concentration. By that measure a micro-rough surface is created, and contact area of film layers is minimized; the distance between the layers is maximized and adherence suppressed. Minerals used for that application should have little to no impact on the mechanical properties of the film; must not deteriorate transparency, haze, color, gloss of the film; and should be compatible with the film-processing process. Several minerals are used for this purpose: talc, calcined kaolin, cristobalite; precipitated silica, diatomaceous earth, mica, calcium carbonates, calcium sulfate (anhydrite), magnesium carbonate, magnesium sulfate, and feldspars.
Organic alternatives used for anti-blocking or anti-stick are amides, fatty acid amides, fatty acids, salts of fatty acids, silicones, or others. They work with different mechanisms compared to the inorganic anti-blocking additives, migrating to the film surface upon cooling and forming a release layer. Sometimes combinations of inorganic and organic anti-blocking additives are used. Organic additives typically have lower anti-blocking ability in comparison to the inorganic ones but better slip effect.
FILLPLAS’s Anti-blocking Additive is widely applied in the production of film packing for PE film.