Thermal degradation and fire behavior of thermoset resins modified with phosphorus containing styrene

Abstract

International audienceIn order to improve the fire behavior of unsatd. polyester resins (UPR) a phosphorus contg. monomer, dimethyl-vinylbenzyl phosphonate (or S1), was used to replace a part of the reactive diluent (styrene). UPR with various phosphorus contents were prepd. Thermal degrdn. was studied using thermogravimetric anal. (TGA) and pyrolysis combustion flow microcalorimeter (PCFC), while fire behavior was investigated by cone calorimeter. The phosphorus yield in the residue was detd. using energy-dispersive X-ray (EDX).TGA pointed out a decrease in thermal stability with increasing S1 content but also an important increase in char formation. Cone calorimetry highlighted pHRR decrease, and from 50% of styrene substitution a barrier effect was evidenced. Residue anal. enabled to det. the partition of phosphorus between vapor and condensed phase. It was shown that this partition depends on the degree of styrene substitution. At high S1 content, interactions between phosphonate groups enable a very efficient condensed phase action by creation of a charred protective barrier. This strategy was also successfully transposed to a vinyl ester resin (VER)

UV-polymerisable, phosphorus-containing, flame-retardant surface coatings for glass fibre-reinforced epoxy composites

“…With increase in heat flux, there is a little effect on char expansion ratio. This intumesced char slows down the decomposition of the epoxy resin in the composite by acting as a barrier to the passage of heat to the underlying substrate and impeding diffusion of volatile combustible product from the substrate to the surface [24]. The excellent thermal barrier and flame retardant properties of the GRE composites afforded by this PVPA coating could be attributed to the high concentration of phosphorus and nitrogen elements in its composition, and to the coating intumescing when heated.…”

Unsaturated Polyesters and Vinyl Esters

“…Phosphorus-pendant groups have been incorporated only recently into the polymeric backbone by Zhang and co-workers [111,112], Tibiletti and co-workers [113], or Novakov and co-workers [114]. The use of 2-[10-(9,10-dihydro-9-oxa-10-phosphaphenantrene-10-oxide-10-yl)]-maleic acid (DOPO-MA) as a flame retardant-conferring monomer for the preparation of unsaturated polyester resins was described by Zhang et al [111,112].…”

“…Alternatively, the styrene cross-linking units can be modified by phosphorous-containing groups to impart improved heat stability as described by Tibiletti et al [113]. In this work, dimethyl vinylbenzylphosphonate was introduced into the styrene molecule, which was subsequently used for the cross-linking of a commercial orthophthalic unsaturated polyester.…”

“…21 Schematic representation of an unsaturated polyester resin fragment modified with dimethyl vinylbenzylphosphonate as the intrinsic flame retardant component[113].…”

Phosphonated Lipids as Primary Plasticizers for PVC with Improved Flame Retardancy

“…The main goal of our researches was to get primary plasticizer exhibiting plasticization closed to that of DINP and simultaneously, flame retardancy avoiding the addition of any additives in PVC during compounding. Phosphonated groups are now well known for their ability to extinguish fire . Thus, four phosphonated vegetable oil derivatives (PMO, PMO2, PML, and PDE) were synthesized by free‐radical addition of dialkyl phosphonates onto lipidic double bonds (Figure ) into C9 or C10 position (and C12 or C13 position for PML).…”