Intrinsic Flame Retardant Research Articles

Property of intrinsic flame retardant epoxy resin cured by functional magnesium organic composite salt and diethylenetriamine

SummaryAn efficient intrinsic flame retardants composite was prepared by curing epoxy resin with a functional magnesium organic composite salt (FMOCS, 0.685 ± 0.3 nm) and diethylenetriamine (DETA). Curing behavior, thermal and flame‐retardant properties of the cured epoxy resins were systematically investigated by infrared spectrum (FTIR), thermogravimetric analysis (TGA), vertical burning test (UL‐94) and limited oxygen index (LOI) measurement. It was found that flame retardancy and mechanical properties of the cured composite are significantly enhanced compared with DETA/EP. The LOI of the EP reached to 33%, which is much higher than the DETA/EP (19%) or its IFR composite (31%) in the optimal addition of ammonium polyphosphate (APP, 18.69 wt %), pentaerythritol (PER, 6.21 wt %) and FMOCS (3.50 wt %). Furthermore, the mechanical properties of the composite material measurement results to imply that it can enhance tensile strength (150%) and bending strength (88%) rather than DETA/EP, which were tested by impact testing machine and microcomputer control electron universal testing machines. Copyright © 2016 John Wiley & Sons, Ltd.

Microencapsulated ammonium polyphosphate with boron‐modified phenolic resin

ABSTRACTAmmonium polyphosphate (APP) was encapsulated with boron‐modified phenolic resin (BPF) by in situ polymerization with the goal of improving its hydrophobicity, thermal stability, and compatibility in polymers. The chemical and physical features of APP microcapsules were characterized by Fourier transform infrared, X‐ray photoelectron spectroscopy, scanning electron microscopy, inductively coupled plasma, and laser particle sizing. The hydrophobicity was assessed by the water contact angle. The residues from thermogravimetric analyzer and muffle burner were investigated. The results showed that the APP microcapsules with BPF shell had been achieved successfully. The shell encapsulation rate mainly depended on the amount of crosslinking agent when the ratio of APP/BPF was constant. The mean particle size increased and the particle size distribution became more narrow. The hydrophobicity of APP was improved and the improvement degree mainly depended on the amount and adding rate of crosslinking agent and the conditions of heat curing. A good thermal stability and high residue char rate at high temperature were noticed for APP microcapsules. It suggests that these microcapsules might be used as an intrinsic flame retardant. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43720.

Waterborne polyurethane conjugated with novel diol chain-extender bearing cyclic phosphoramidate lateral group: synthesis, flammability and thermal degradation mechanism

A diol bearing cyclic phosphoramidate pendant group was synthesized and covalently conjugated into waterborne polyurethane. The polyurethane possesses long-term hydrolytic stability and good intrinsic flame retardancy.

A novel biobased epoxy resin with high mechanical stiffness and low flammability: synthesis, characterization and properties

A novel bio-epoxy resin, TPEU-EP, was developed. It possesses good intrinsic flame retardancy, low smoke production, and excellent mechanical properties, showing high promise for application.

A novel halogen-free flame retardant poly (vinyl alcohol) foam with intrinsic flame retardant characteristics prepared through continuous extrusion

This paper reported a novel halogen-free flame retardant poly (vinyl alcohol) (PVA) foam with intrinsic flame retardant characteristics prepared through continuous extrusion using water as blowing agent. The morphology, cellular structure, mechanical properties and flame retardancy of the foams were systematically investigated. The experiments showed that PVA was not only the flame retardant target foam matrix, but also played an important role in char forming reactions, water not only acted as plasticizer and blowing agent for PVA thermal foaming, but also an effective synergistic flame retardant by evaporation to cool the system and suppress the point of inflammability, and melamine phosphate (MP) as halogen-free flame retardant was well dispersed in PVA matrix due to the strong interaction between MP and PVA, and also acted as excellent heterogeneous nucleating agent for foaming. The prepared halogen-free flame retardant PVA foam had good cellular structure, excellent flame retardancy and mechanical properties, i.e. apparent density 0.25 g/cm3, average cell diameter 450 μm, cell density 103 cells/cm3, reaching UL94 V-0, LOI 35%, tensile strength 1.8 MPa and elongation at break 57.1%. The novel halogen-free flame retardant PVA foam has potential applications.

Rigid bio-foam plastics with intrinsic flame retardancy derived from soybean oil

Acrylated epoxidized soybean oil was chemically grafted with difunctional flame retardants carrying phosphorus, double bonds or biphenyl groups, and then copolymerized with styrene to produce bio-foams with high mechanical properties and intrinsic flame resistance. Owing to the introduction of rigid comonomer, phosphorus, additional double bonds or biphenyl side groups, the bio-foams showed compressive strength similar to that of conventional unsaturated polyester foam, antiflaming capability and biodegradability as well. More importantly, the modified flame retardant partially took the role of styrene, leading to a lower fraction of petroleum based substance in the bio-foams without the expense of foam strength, and improved biodegradability. The comparison between the bio-foams with intrinsic flame retardancy on a molecular level and those containing inflaming retardant fillers revealed that the latter have acquired rather poor mechanical properties and hence are obviously inferior to the former in practical applications where a load-bearing capability is required.