SYLOBLOC® Antiblocking Agents

SYLOBLOC® silica particles, which typically have average particle sizes between 2 and 10 micrometers, function by imparting roughness to plastic films, reducing the surface area on which films contact each other. This reduces blocking between individual layers of film and is important to prevent loss of functionality during production, storage, processing, and converting. SYLOBLOC® particles vary pore volume between 0.4 and 2.0 mL/g, where larger-pore-volume grades tend to provide better antiblocking efficiency. Based on the type of plastic, there is a SYLOBLOC® grade that optimizes workability and performance by balancing antiblocking efficiency and dispersibility. Large-pore-volume SYLOBLOC® grades, for example, which are typically more difficult to disperse in polymer melts, tend to be used in PET films, where they are dispersed in situ during the polymerization reaction or introduced in masterbatching. Smaller-pore-volume grades, which are easier to disperse in polymer melts, are typically used in PP and PE films. Selecting a grade is also dependent on the particle size and film thickness, where smaller particle sizes are used for thinner films. In terms of particle size, optical properties are not a factor because there is minimal light-scattering effect and maximum transparency, even from the smallest to the largest of SYLOBLOC® grades.

SYLOBLOC® silica antiblocking agents are used in several film applications. Perhaps the most common application is packaging films for food and consumer goods, as SYLOBLOC® is FDA and BGA compliant. Other applications include films used in medical and agricultural settings, while specialty applications include photovoltaic backsheets, transfer films, release films, and electrically insulating films.