A European chocolate-maker faced a daunting challenge, both to protect its customers’ safety, and its brand reputation. The EU had updated its food contact materials legislation (Commission Regulation (EU) No.10/2011), limiting acrylonitrile monomer residue to below 10 parts per million (ppm) in food contact plastics, to prevent harmful chemicals leaching into the food. This particular company uses acrylonitrile butadiene styrene (ABS) to make the toys that come with its chocolate products, to take advantage of the polymer’s physical strengths. Therefore, the chocolate-maker needed an ABS manufacturer that could meet the new limits. Because of its own high standards, the company had also reduced its internal monomer residue limit even further to 5 ppm. Yet, the chocolatier soon found that very few manufacturers could maintain a consistent quality below even 20 ppm. After testing its various global ABS suppliers, CHIMEI was the only one to achieve a result below 5 ppm. However, consistently mass producing that high quality seemed impossible.

How Best To Clean The ABS?

At CHIMEI, we took on the challenge to help our customer achieve their ambitious goal. At first we considered optimizing the cleaning process that other manufacturers had already attempted and abandoned. That involved simply re-processing the ABS until it met the right standard. However, the rigidity, and tensile and impact strength of the resulting ABS was insufficient, not to mention the process itself was costly, inefficient, and created excessive waste water. We went back to the drawing board, to formulate a new approach that would be feasible and sustainable on a mass scale. After a lengthy R&D process, we developed a pioneering system that cleans the individual input materials — acrylonitrile, polybutadiene, and styrene — before combining them into the final ABS. This allows us to consistently control the monomer residue levels, without negatively affecting the physical properties of the final ABS.

Meeting The New Regulations

With CHIMEI’s consistent supply of clean ABS, the chocolate-maker can now comfortably adhere to the EU regulations. In addition, the know-how we gained from this innovation process also allows us to help other companies meet and exceed the EU’s high standards, which are now beginning to be accepted in other regions.