polybutylene terephthalate (PBT) [125]; the resultant polymers showed V-1 rating
in the UL-94 test and anti-dripping characteristics. At the same FR weight loading,
PU polymers achieved V-0 rating in the UL-94 test. FTIR analysis revealed that
P–N present in the char improve intumescent char strength and formation at high
temperatures. Similarly, benzonitrile-containing bicyclic phosphates (PDN) were
synthesized and used as FR additives for epoxy polymers; they exhibited strong FR
Scheme 4.11 Structures of some caged bicyclic phosphorus, phosphate, and phosphonate oxide
derivative compounds for flame retardant applications. Redraw on the basis of information collected from [130, 131]
4.3 Phosphorus-Based FRs
33
in the UL-94 test and anti-dripping characteristics. At the same FR weight loading,
PU polymers achieved V-0 rating in the UL-94 test. FTIR analysis revealed that
P–N present in the char improve intumescent char strength and formation at high
temperatures. Similarly, benzonitrile-containing bicyclic phosphates (PDN) were
synthesized and used as FR additives for epoxy polymers; they exhibited strong FR
Scheme 4.11 Structures of some caged bicyclic phosphorus, phosphate, and phosphonate oxide
derivative compounds for flame retardant applications. Redraw on the basis of information collected from [130, 131]
4.3 Phosphorus-Based FRs
33