Title: New Generation of Accelerators Addressing Human Health Concerns and Enabling Renewable Composites
Authors: Gina Butuc, Raymond ten Broeke, Roel Zuijderduin, Gea Spijkerman
Abstract: The role of Cobalt (Co) accelerators in thermoset applications that are peroxide cured, is well known and documented. Due to the presence of a heavy metal, Co accelerators pose a potential human health concern. In addition to the health concern, Co accelerators have a limited efficacy in a series of applications.
Novel copper (Cu) and iron (Fe) based accelerators have been developed to address the human health concern. In addition to the human health benefit, these accelerators can correct some of the drawbacks of Co accelerators. An application benefit for novel accelerators is showcased in thermoset applications where bio-based fibers are present. Bio-based fibers have many desirable attributes such as sustainable, renewable supply and weight savings over other popular materials such as engineered glass. However, it is also known that biofibers have a higher moisture content than synthetic fibers, that render Co accelerators inefficient. The efficacy of the novel accelerators is demonstrated on side-by-side comparisons against standard cobalt systems in commercial applications. The cure rate is not impacted when the new accelerators are used in combination with organic peroxides. This efficient cure is demonstrated in bio-reinforced composites by Resin Transfer Molding (RTM), vacuum infusion, hand lay-up/spray-up, engineered stone, polymer concrete, filament winding and continuous lamination applications.
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Conference: CAMX 2022
Publication Date: 2022/10/17
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