
Milliken’s Milliguard AOX-1 Antioxidant for Polyurethane Vehicle Interiors.
Milliguard AOX-1, the novel polymer-bound antioxidant for polyurethane (PU), developed by Milliken & Company to address more stringent environmental, health and safety requirements while delivering outstanding thermal stabilisation performance at low loadings.
It offers a unique solution for compliance with tougher vehicle indoor air quality by contributing negligible volatile organic compound (VOC) and outgassing condensation (FOG) content in emissions testing.
Milliguard AOX-1 antioxidant also offers unparalleled efficiency in stabilising free radicals that can degrade polyurethane (PU) foam, and is highly synergistic with other antioxidant classes.
This Milliken technology provides polyol producers and foam manufacturers with a powerful tool for interior vehicle components such as seats, door trim, carpet, instrument panels, headliners and consoles.
Jesse Shoultz, Global Market Manager for Performance Colorants & Ingredients at Milliken & Company, said: “Our patented Milliguard AOX-1 antioxidant can play an important role in helping passengers breathe more easily when travelling in a vehicle.
“When incorporated in polyols or added during foaming, this antioxidant reacts into the polymer backbone to deliver reduced VOC emissions and outstanding performance at lower loadings, two very important benefits to customers. By enabling PU foam to meet new, tougher standards for vehicle indoor air quality across the globe, Milliguard AOX-1
antioxidant helps our customers address the latest market challenges.”
Internally achieved test results consistently showed that Milliguard AOX antioxidant significantly reduced VOC content by more than two thirds to 22 ppm, compared to the industry standard 69 ppm.
Milliken’s antioxidant also dramatically minimised FOG content emission to only 6 ppm, compared to the industry standard 541 ppm.
The reference method for determination of VOC and FOG levels is the VDA278 standard developed by Daimler and used by BMW, Porsche and Volkswagen.
Stability and Sustainability
Milliguard AOX-1 antioxidant is a reactive, carbon-cantered radical scavenger used to protect PU polymers, which are exposed to high heat conditions during foaming, from thermal degradation that causes discolouration and physical property failure.
Combining Milliguard AOX-1 antioxidant with conventional peroxy and alkoxy radical stabilisers provides ultimate thermal stability.
The Milliken product interacts synergistically with other antioxidant classes an
d also reacts earlier in the oxidation cycle to provide unparalleled levels of stability.
Milliken engineered Milliguard AOX-1 additive to be covalently bound with the urethane polymer.
This unique approach prevents the antioxidant from migrating to the surface and virtually eliminates VOC and FOG emissions from the final component.
Milliguard AOX-1 antioxidant also contributes to environmental protection by enhancing the performance of natural oil polyols (NOPs) and non-halogenated flame retardants.
The use of NOPs for PU is forecast to grow strongly as the industry strives to include renewable raw materials in formulations.
A major concern however is the higher levels of discolouration that results from NOPs, but Milliguard AOX-1 antioxidant provide a solution to this issue.
By facilitating the use of naturally derived polyols without concerns about out-of-control auto-oxidation, which helps to encourage great use of NOPs.
Likewise, using non-halogenated flame retardants cause increased discolouration in a part, as well as phenol emissions from degradation of phosphate ester flame retardants.
In an effort to reduce this, Milliguard AOX-1 antioxidant has been developed to stabilise non-halogenated flame retardants, reducing both discolouration and phenol emissions.