Increasing productivity in plastics processing
Plastics have become an integral part of life. Without considering numerous other applications, their uses in packaging for foods and beverages and as housings for electronic equipment make them a part of every household. Reaction injection moulding (RIM) is a common forming process used to create products from plastics. Compounds are mixed together as they are injected into a mould, where they are allowed to set (harden) before being removed. Plastics are polymers, long chains of subunits (monomers) linked together. Conventionally, polymerisation (the chemical reaction leading to formation of polymers) begins in the injection nozzle head, where compounds are first brought together and mixed, and continues in the mould. The in-mould cycle time is between three and four minutes. European researchers decided to boost the competitiveness of SMEs in the RIM field by reducing the in-mould cycle time to approximately 45 seconds, 4 to 5 times faster than currently achieved. In particular, with EU funding for the Dynamic project, the consortium developed novel monitoring and control sensors to speed the polymerisation reaction within the mixer as well as decrease the viscosity (increase flow rates) of the polymer. The pilot studies demonstrated that the system is capable of being fully integrated with existing equipment. Enthusiasm on the part of partner SMEs should facilitate rapid commercial exploitation of the Dynamic project’s concepts. Implementation of the novel technology has the potential to dramatically decrease mould cycle times, clamp pressures and energy consumption while increasing machine throughput thus successfully boosting the competitiveness of the EU’s SMEs in the RIM field.
