Polymer-Clay Nanocomposities: One Way to Improve the Barrier Properties of Degradable Polymers, 2001 European PLC Conference Proceedings

Mikael Krook, Mikael Hedenqvist--In the late 80’s degradable polymers for packaging use became popular. Since then, research has been conducted on these materials and today several commercial available polymers exist on the market. To be successfully used in applications such as coated paperboard the barrier properties must be improved. An interesting way to do this is to incorporate nanoscale particles into the polymer matrix. These reinforced plastics, known as nanocomposites, are formed by very thin platelets of surface-modified clay, dispersed in a thermoplastic or a reactive liquid resin. The clay platelets which are silicate structures provide an efficient reinforcement of polymers because of their small size (10 Å), large surface area (400-700 square meters/g) and high aspect ratio (>200:1). Due to the small size of the particles, nanocomposites will keep some of the unfilled polymer characteristics, such as flexibility and transparency. Since the introduction of the concept of polymer nanocomposites in the late 1980’s by Toyota, research has escalated and commercial products are being introduced to the market. Extrusion coating of polymer nanocomposites onto paperboard in single layer as well as multilayer with other polymers could give a new high barrier material.