Sumitomo Bakelite develops way to recover, reuse phenolic resin

New Materials Asia, Dec, 2006

Sumitomo Bakelite Co Ltd, Japan, has developed a method to reclaim and reuse the phenolic resin found in products such as electronic components and autoparts.

Phenolic resin, also known as Bakelite, is synthesized by using a cross-linking agent to bind the stringy phenol molecules into a mesh-like structure. As the resultant material is extremely stable, it is difficult to decompose, and until now, there has been no practical way to recover and reuse the phenol molecules.

In the novel procedure, the resin is pulverized into a micropowder, then placed in a reaction vessel with water, phenol and a catalyst, then heated to 260[degrees]C while subjected to a high pressure of 7 MPa (70 atmospheres). This creates a subcritical state in which the water-phenol mixture exists in both the liquid and gaseous forms, and the heat breaks down the cross-linking agent.

According to Sumitomo, the string-like phenol molecules can be reclaimed and reused to make a phenolic resin that retains around 90% of the bending strength and heat resistance of the material, which makes it suitable for practical applications.

The company plans to study the recovery process at a pilot plant and believes that once it is scaled up to mass-production, the technique can be used to produce lower-cost recycled phenolic resin.

For further information, contact: Sumitomo Bakelite Co Ltd, 2-5-8 Higashi-Shinagawa, Shinagawa-ku, Tokyo, Japan; Internet: www.sumibe.co.jp/english