Bob Howell, Central Michigan University, presented phosphorus reacted isosorbides as possible bio-sourced PIN FRs. Production is starch -> D-glucose -> D-sorbitol -> isosorbitol -> phosphorus esters. The resulting molecules are phosphates, phosphinates or phosphonates / propanoate, enoate or thiatetradecanoate.
They can be optimised to have lower oxygen than phosphorus content in order to be active in gas phase flame inhibition. These molecules were selected because their structure leads to expect them to be biodegradable and of low toxicity.