Synergistic effects of aluminum hydroxide, red phosphorus, and expandable graphite on the flame retardancy and thermal stability of polyethylene

A novel intumescent ﬂame retardant (IFR), melamine modified enzymatic hydrolysis lignin (MEHL), was synthesized and well characterized by FTIR and TGA. The results showed that the decompose temperature of MEHL is much higher than that of enzymatic hydrolysis lignin (EHL). In order to improve ﬂame retardancy and dripping resistance of EPDM, MEHL and microencapsulated red phosphorus (MRP) were added into EPDM as IFR system. The ﬂame ability and thermal stability of IFR and EPDM composites were investigated by UL-94 vertical burning test and LOI measurements. The results indicated that FV-0 was reached and the LOI value was 35 when per hundred rubber (phr) together with 12 phr MRP and 50 phr EHLM were added. SEM photos showed that the char residue was continuous, and a barrier between flame and rubber was formed, while there were also small holes in its surfaces. On all accounts, EHL used as a carbonization agent instead of petroleum chemicals, such as pentaerythritol, was more environmental friendly and beneficial to economy.

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Effect of Red Phosphorus Masterbatch on Flame Retardancy and Thermal Stability of Polypropylene/Thermoplastic Polyurethane Blends

Polymers and Polymer Composites ◽

10.1177/096739111502300208 ◽

2015 ◽

Vol 23 (2) ◽

pp. 113-120 ◽

Cited By ~ 1

Author(s):

Yang Xu ◽

Mengqi Tang ◽

Xiaolang Chen ◽

Man Chen ◽

Jie Yu ◽

...

Keyword(s):

Thermal Stability ◽

Flame Retardancy ◽

Thermoplastic Polyurethane ◽

Red Phosphorus ◽

Thermal Stability Of

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The synergism between melamine and expandable graphite on improving the flame retardancy of polyamide 11

High Performance Polymers ◽

10.1177/0954008316628965 ◽

2016 ◽

Vol 29 (1) ◽

pp. 77-86 ◽

Cited By ~ 16

Author(s):

Xiaodong Jin ◽

Chen Chen ◽

Jun Sun ◽

Xing Zhang ◽

Xiaoyu Gu ◽

...

Keyword(s):

Thermal Stability ◽

Flame Retardancy ◽

Microscopic Analysis ◽

Expandable Graphite ◽

Electron Microscopic ◽

Limiting Oxygen Index ◽

Polyamide 11 ◽

The Matrix ◽

In Fire ◽

Thermal Stability Of

Expandable graphite (EG) has attracted more and more attention in fire science society due to its excellent char-forming ability, however, it cannot meet commercial flame-retardant requirements because of the low intensity of the char. This work reported our very recent efforts on improving the char quality of EG by introducing melamine (MEL) in order to enhance the fire resistance and thermal stability of polyamide 11 (PA 11) composite. The flammability characterized by limiting oxygen index, UL-94 vertical burning, and cone calorimeter (cone) tests shows that the presence of both EG and MEL can significantly improve the flame retardancy and thermal stability of PA 11 composites. The scanning electron microscopic analysis shows that EG and MEL are beneficial to form compact char layers that can isolate the matrix from heat and oxygen. It is proposed that the formation of hydrogen bonds between MEL and PA 11 are crucial for improving the flame retardancy of the composites.

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Synergistic effects of red phosphorus masterbatch with expandable graphite on the flammability and thermal stability of polypropylene/thermoplastic polyurethane blends

Polymers and Polymer Composites ◽

10.1177/0967391119869552 ◽

2019 ◽

Vol 28 (3) ◽

pp. 209-219 ◽

Cited By ~ 2

Author(s):

Na Wang ◽

Lingtong Li ◽

Yang Xu ◽

Kun Zhang ◽

Xiaolang Chen ◽

...

Keyword(s):

Thermal Stability ◽

Heat Release ◽

Flame Retardant ◽

Synergistic Effects ◽

Thermoplastic Polyurethane ◽

Expandable Graphite ◽

Gravimetric Analysis ◽

Red Phosphorus ◽

Limiting Oxygen Index ◽

Ul 94

The flammability characterization and synergistic effects of red phosphorus masterbatch (RPM) with expandable graphite (EG) in flame-retardant polypropylene (PP)/thermoplastic polyurethane (TPU) composites are investigated by limiting oxygen index, UL-94 testing, cone calorimeter tests, thermal gravimetric analysis, Fourier transform infrared (FTIR), and scanning electron microscopy. The results show that the flame retardancy of PP/TPU/EG/RPM composites is greatly influenced by RPM. The synergistic effects between RPM and EG take place in the flame-retardant composites. The presence of RPM with EG decreases significantly the heat release rates and total heat release, and UL-94 V-0 rating is achieved when suitable amount of RPM substitutes for EG in the PP/TPU/EG/RPM composites. The T onset and T 10 wt% of the composites are improved because of the presence of RPM. The FTIR spectra show that the incorporation of RPM improves the thermo-oxidative stability of PP/TPU at higher temperatures. The morphological observations indicate the reinforcement of thermal stability, and flame-retardant performance is attributed to the compact and stable char layers promoted by RPM with EG acted as an effective heat barrier and thermal insulation.

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