Insights into Phosphorus-Containing Flame Retardants …
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Tris(2,3-dibromopropyl) phosphate (TDBPP) and Tris(tribromoneopentyl) phosphate (TTBPP).
Br-aliphatic: Brromine-based P–C aliphatic bond containing FRs are found effective FRs, for example, Phenylpropan-2-ylhydrogen phosphate (PPHP), 2Ethylhexyldiphenyl phosphate (EHDPP), Isodecyldiphenyl phosphate (IDPP) etc.
Aromatic: In the previous few decades aromatic phosphates possess strong flameretardant properties [34]. Common examples are Triphenyl phosphate (TPP), Tricresyl phosphate (TCP), Triisopropyl phosphate (TIPP), Cresyl diphenylphosphate (CDPP), 6H-Dibenz[c,e] [1, 2] oxaphosphorin,6-oxide (DOPO), Bisphenol-A
bis-(diphenylphosphate) (BPA-BDPP) etc.
1.3.2 Organophosphonate FRs
Organophosphonates were extensively developed and used as FRs. Many commercially accepted compounds based on organophosphonate specification have been
generated and successfully employed as FRs and composed of two types:
Aliphatic: FRs with P–C aliphatic bond having phosphonate group are shown in
Table 1 and commonly include Dimethyl hydrogen phosphonate (DMHP), Diethyl
hydrogen phosphonate (DEHP), Dimethylethyl phosphonate (DMEP), Dimethylmethyl phosphonate (DMMP), Dimethylpropyl phosphonate (DMPP), Dimethylallyl
phosphonate (DMAP) as well as a Cyclic tert-butyl phosphonate (TBP).
Aromatic: FRs with P–C aromatic bond having phosphonate group FRs were derived
from the transformation of aliphatic moiety with aromatic units. A monosubstituted
phosphorus compound (Ar-Phosphonate derivative 1, m.p. 184–187 °C) and a disubstituted phosphorus compound (Ar-Phosphonate derivative 2, m.p. 258–260 °C) were
obtained as a mixture using modified separation and purification steps [37]. The phosphonate product diethyl-(2-hydroxy-5-vinylphenyl) phosphonate (Ar-Phosphonate
derivative 4) was fabricated from diethyl-(4-vinylphenyl)phosphate (Ar-Phosphonate
derivative 3) using ethoxy-P-acid [38]. Su et al. [39] patented the P-enabled esterification of phenol or polyhydroxybenzenes to develop several OPFRs. one example
is compounds Ar-Phosphonate derivative 5 obtained from bisphenol A [39].
Another two phenolic white crystals/compounds (Ar-Phosphonate derivative 6,
m.p. 169–171 °C and 7, m.p. 216–217 °C) were prepared through [1, 3]-sigmatropic
rearrangement and were found to have high-performance against polymers [40].
1.3.3 Organophosphinites FRs
Recently, synthesis and applications of different phosphinic acid derivatives have
been reported excel flame resistant abilities [41]. Examples of organophosphinites FRs are Diethylphosphinic acid (DEPA), Phenylphosphinic acid (PPA),
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Tris(2,3-dibromopropyl) phosphate (TDBPP) and Tris(tribromoneopentyl) phosphate (TTBPP).
Br-aliphatic: Brromine-based P–C aliphatic bond containing FRs are found effective FRs, for example, Phenylpropan-2-ylhydrogen phosphate (PPHP), 2Ethylhexyldiphenyl phosphate (EHDPP), Isodecyldiphenyl phosphate (IDPP) etc.
Aromatic: In the previous few decades aromatic phosphates possess strong flameretardant properties [34]. Common examples are Triphenyl phosphate (TPP), Tricresyl phosphate (TCP), Triisopropyl phosphate (TIPP), Cresyl diphenylphosphate (CDPP), 6H-Dibenz[c,e] [1, 2] oxaphosphorin,6-oxide (DOPO), Bisphenol-A
bis-(diphenylphosphate) (BPA-BDPP) etc.
1.3.2 Organophosphonate FRs
Organophosphonates were extensively developed and used as FRs. Many commercially accepted compounds based on organophosphonate specification have been
generated and successfully employed as FRs and composed of two types:
Aliphatic: FRs with P–C aliphatic bond having phosphonate group are shown in
Table 1 and commonly include Dimethyl hydrogen phosphonate (DMHP), Diethyl
hydrogen phosphonate (DEHP), Dimethylethyl phosphonate (DMEP), Dimethylmethyl phosphonate (DMMP), Dimethylpropyl phosphonate (DMPP), Dimethylallyl
phosphonate (DMAP) as well as a Cyclic tert-butyl phosphonate (TBP).
Aromatic: FRs with P–C aromatic bond having phosphonate group FRs were derived
from the transformation of aliphatic moiety with aromatic units. A monosubstituted
phosphorus compound (Ar-Phosphonate derivative 1, m.p. 184–187 °C) and a disubstituted phosphorus compound (Ar-Phosphonate derivative 2, m.p. 258–260 °C) were
obtained as a mixture using modified separation and purification steps [37]. The phosphonate product diethyl-(2-hydroxy-5-vinylphenyl) phosphonate (Ar-Phosphonate
derivative 4) was fabricated from diethyl-(4-vinylphenyl)phosphate (Ar-Phosphonate
derivative 3) using ethoxy-P-acid [38]. Su et al. [39] patented the P-enabled esterification of phenol or polyhydroxybenzenes to develop several OPFRs. one example
is compounds Ar-Phosphonate derivative 5 obtained from bisphenol A [39].
Another two phenolic white crystals/compounds (Ar-Phosphonate derivative 6,
m.p. 169–171 °C and 7, m.p. 216–217 °C) were prepared through [1, 3]-sigmatropic
rearrangement and were found to have high-performance against polymers [40].
1.3.3 Organophosphinites FRs
Recently, synthesis and applications of different phosphinic acid derivatives have
been reported excel flame resistant abilities [41]. Examples of organophosphinites FRs are Diethylphosphinic acid (DEPA), Phenylphosphinic acid (PPA),