Recent Advances in Flame Retardant Compositions UV Stable and Antimony Free Flame Retardant Systems for Polypropylene Molding

摘要

Hindered amines are known for their ability to provide UV stability as well as long term thermal stability. Recently, there have been new classes of hindered amines, based on the novel NOR functionalization, that afford additional benefits beyond UV or long term thermal stability. For example, over the last several years we have clearly established the utility of novel NOR type hindered amines, such as NOR 1, either as a flame retardant, or flame retardant synergist in combination with conventional halogenated flame retardants in polyolefin thin section substrates, e.g., polypropylene fibers. In this paper, we will provide an update on the recent advances in thick section substrates including both flame retardant efficacy and UV stability. Overall, we have found that these novel NOR type hindered amines not only allow for substantial reduction in the overall concentration of the bromine compounds, mineral fillers, or/and the elimination of antimony trioxide flame retardant synergist but also, they provide superb UV stability in the presence of halogenated flame retardant. Antimony free, UV stable flame retardant systems for polypropylene homopolymer molding with UL 94 V-0 and V-2 ratings respectively, have been achieved.