Phosphorus and Nitrogen-Containing Polyols: Synergistic Effect on the Thermal Property and Flame Retardancy of Rigid Polyurethane Foam Composites

The current study aims at comparatively investigating the effect of apparent density on flame retardancy, thermal degradation and combustion behaviors of rigid polyurethane foam (RPUF), RPUF/ expandable graphite (EG) and RPUF/ ammonium polyphosphate (APP). A series of RPUF, RPUF/EG and RPUF/APP samples with different apparent densities (30, 60 and 90 kg/m3) were prepared. The flame retardancy, thermal degradation, and combustion behaviors of each sample were investigated. Limiting oxygen index (LOI) results indicated that increasing apparent density was beneficial to the flame retardancy of all foam systems. The effect of apparent density on the enhancement of flame retardancy followed the sequence of RPUF < RPUF/APP < RPUF/EG. Thermogravimetric analysis (TGA) results showed that an increase in the apparent density can cause more weight loss in the first degradation stage and less weight loss in the second degradation stage for all foam systems. The combustion behaviors also showed significant differences. The samples with a higher apparent density showed a longer duration of heat release and higher total heat release (THR). The findings in this study demonstrated that apparent density played an important role in flame retardancy, thermal degradation, and combustion behaviors of RPUF, which must be paid more attention in the studies of flame-retardant RPUF.

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Synergistic effect of nano magnesium amino-tris-(methylenephosphonate) and expandable graphite on improving flame retardant, mechanical and thermal insulating properties of rigid polyurethane foam

Materials Chemistry and Physics ◽

10.1016/j.matchemphys.2018.08.010 ◽

2018 ◽

Vol 219 ◽

pp. 318-327 ◽

Cited By ~ 14

Author(s):

Lei Liu ◽

Zhengzhou Wang

Keyword(s):

Synergistic Effect ◽

Flame Retardant ◽

Polyurethane Foam ◽

Expandable Graphite ◽

Rigid Polyurethane Foam ◽

Thermal Insulating ◽

Insulating Properties

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Effects of Tung Oil-Based Polyols on the Thermal Stability, Flame Retardancy, and Mechanical Properties of Rigid Polyurethane Foam

Polymers ◽

10.3390/polym11010045 ◽

2018 ◽

Vol 11 (1) ◽

pp. 45 ◽

Cited By ~ 10

Author(s):

Wei Zhou ◽

Caiying Bo ◽

Puyou Jia ◽

Yonghong Zhou ◽

Meng Zhang

Keyword(s):

Thermal Stability ◽

Polyurethane Foam ◽

Flame Retardancy ◽

Covalent Bond ◽

Rigid Polyurethane Foam ◽

Limiting Oxygen Index ◽

Sem Micrographs ◽

Tung Oil ◽

Char Layer ◽

Ring Opening Reaction

A phosphorus-containing tung oil-based polyol (PTOP) and a silicon-containing tung oil-based polyol (PTOSi) were each efficiently prepared by attaching 9,10-dihydro-9-oxa-10-phosphaphenanthrene (DOPO) and dihydroxydiphenylsilane (DPSD) directly, respectively, to the epoxidized monoglyceride of tung oil (EGTO) through a ring-opening reaction. The two new polyols were used in the formation of rigid polyurethane foam (RPUF), which displayed great thermal stability and excellent flame retardancy performance. The limiting oxygen index (LOI) value of RPUF containing 80 wt % PTOP and 80 wt % PTOSi was 24.0% and 23.4%, respectively. Fourier transfer infrared (FTIR), Nuclear Magnetic Resonance (NMR) and thermogravimetric (TG) analysis revealed that DOPO and DPSD are linked to EGTO by a covalent bond. Interestingly, PTOP and PTOSi had opposite effects on Tg and the compressive strength of RPUF, where, with the appropriate loading, the compressive strengths were 0.82 MPa and 0.25 MPa, respectively. At a higher loading of PTOP and PTOSi, the thermal conductivity of RPUF increased while the RPUF density decreased. The scanning electron microscope (SEM) micrographs showed that the size and closed areas of the RPUF cells were regular. SEM micrographs of the char after combustion showed that the char layer was compact and dense. The enhanced flame retardancy of RPUF resulted from the barrier effect of the char layer, which was covered with incombustible substance.

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Preparation of Rigid Flame Retardancy Polyurethane Foam Material with Difficult Combusted Degree

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.535-537.1151 ◽

2012 ◽

Vol 535-537 ◽

pp. 1151-1157

Author(s):

Zhen Hui Qiu ◽

Yuan Bao Sun ◽

Zhan He Du

Keyword(s):

Synergistic Effect ◽

Polyurethane Foam ◽

Flame Retardancy ◽

Flame Retardants ◽

Oxygen Index ◽

Orthogonal Experiment ◽

Foam Material ◽

Pu Foam ◽

Series Of Experiments

The flame retardants used for the rigid PU foam material were studied systematically in this paper and a series of experiments were carried out to test the oxygen index (OI) of it. The synergistic effect in the different flame retardants also be verified to achieve a well flame retardancy performance. The best ingredients were found out by an orthogonal experiment which can give the PU foam maeterial a difficult combusted degree with the oxygen index higher than 34.

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