Partnered with The Oakland EcoBlock, the roofing materials group searched for compounds to replace the UV protection HALS compounds that typically suffuse TPO (thermoplastic polyolefin) roofing membranes. Although HALS compounds are effective and regenerative (individual HALS molecules can undergo multiple antioxidant cycles), they are toxic and tend to leach out of the membrane, posing an environmental threat . This group investigated a strategy of coupling natural antioxidants such as Vitamin C, Vitamin E, and poly-catechin to produce a regenerative antioxidant solution.