ANTI-BLOCKING AGENTS FOR ELASTOMERIC POLYMER PELLETS
Publication Date: 2004-Dec-30
The IP.com Prior Art Database
Minimize blockiness of elastomeric hydrogenated block copolymer pellets by (a) applying comminuted or ground rigid hydrogenated block copolymer to exterior surfaces of the elastomeric pellets or (b) applying an aqueous dispersion of rigid hydrogenated block copolymer to such exterior surfaces.
Anti-blocking Agents for Elastomeric Polymer Pellets
Elastomeric polymer pellets, especially elastomeric hydrogenated block copolymer pellets, have a tendency to “block” or stick together in clumps of pellets. This tendency interferes with, among other things, solids conveying characteristics of the material.
In an effort to reduce or minimize blocking, any of a number of conventional anti-block materials may be applied to the exterior surfaces of an elastomeric polymer pellet. Such anti-block materials include calcium stearate and talc, both in the form of a powder.
Conventional anti-block materials lack full compatibility with the elastomeric polymers. This lack of full compatibility manifests itself in articles formed from such polymers by one or both of two phenomena. First, the anti-block materials may plate out within the article. Second, the anti-block materials may tend to bloom to the surface of the article. In either event, plating and/or blooming cause the article to be less than optically clear.
Elastomeric polymer processors desire a combination of ease of handling and optical clarity. Two techniques provide that combination.
In one technique, particularly useful when the elastomeric polymer is an elastomeric hydrogenated block copolymer, apply comminuted or ground rigid hydrogenated block copolymer to exterior surfaces of elastomeric polymer pellets. As the rigid hydrogenated block copolymers are completely compatible with the elastomeri...