Synergistic effects of ammonium polyphosphate and red phosphorus with expandable graphite on flammability and thermal properties of HDPE/EVA blends

Abstract

In this work, the flame‐retardant high‐density polyethylene/ethylene vinyl‐acetate copolymer (HDPE/EVA) composites have been prepared by using expandable graphite (EG) as a flame retardant combined with ammonium polyphosphate (APP) and red phosphorus masterbatch (RPM) as synergists. The synergistic effects of these additives on the flammability behaviors of the filled composites have been investigated by limiting oxygen index, UL‐94 test, cone calorimeter test, thermogravimetric analysis (TGA), Fourier‐transform infrared (FTIR), and scanning electron microscopy. The results show that APP and RPM are good synergists for improving the flame retardancy of EG‐filled HDPE/EVA composites. The data from TGA and FTIR spectra also indicate the synergistic effects of APP and RPM with EG considerably enhance the thermal degradation temperatures but decrease the charred residues of the HDPE/EVA/EG composites because the flame‐retardant mechanism has changed. The morphological observations present positive evidences that the synergistic effects take place in APP and RPM with EG in flame‐retardant EG‐filled HDPE/EVA/EG composites. The formation of stable and compact charred residues promoted by APP and RPM with EG acts as effective heat barriers and thermal insulations, which improves the flame‐retardant performances and prevents the underlying polymer materials from burning. Copyright © 2015 John Wiley & Sons, Ltd.

Hugely enhanced flame retardancy and smoke suppression properties of UHMWPE composites with silicone‐coated expandable graphite

“…[3][4][5] It is widely used in military industry, transportation, textile, and cable industry, 6 which needs extremely high-flameretardant performance. 7,8 Recently, expandable graphite (EG) 9 and ammonium polyphosphate (APP) 10 became alternative additives instead of halogen-included flame retardants because of the environment protection regulations. 11,12 Nevertheless, the deterioration of mechanical properties of composites is also due to the addition of more flame retardants.…”

“…UHMWPE composites give higher TSR and SPR values than pure UHMWPE, indicating that the introduction of APP in UHMWPE leads to high smoke emission 9,27. Moreover, UHMWPE/APP15, UHMWPE/(APP/EG)15, and UHMWPE/(APP/SEG)15 give an decrement order in TSR and SPR value, revealing that EG play a key role in suppressing product of smoke, whereas silicone-modified EG gives higher smoke suppress property 28.…”

Preparation of antistatic high‐density polyethylene composites based on synergistic effect of graphene nanoplatelets and multi‐walled carbon nanotubes

“…High‐density polyethylene (HDPE) is one of the most commonly used polyolefin materials in various areas of the polymer industry . However, the high insulation of HDPE limits applications in some fields because a very high voltage can be generated quickly.…”

“…High-density polyethylene (HDPE) is one of the most commonly used polyolefin materials in various areas of the polymer industry. [1][2][3] However, the high insulation of HDPE limits applications in some fields because a very high voltage can be generated quickly. Especially in dry conditions, this can lead to electrostatic discharge with sparks and shocks, which may result in instigating fires if this occurs in certain settings, such as a gasoline service station.…”

Flame‐retarded polyethylene terephthalate with carbon microspheres/magnesium hydroxide compound flame retardant

“…1,2 In view of the defects of single component flame retardants, synergistic or compound flame-retardant technology has become an important direction in the development of flame retarding technology because of its obvious merits such as low dosage of flame retardant and excellent flame-retardant effect. 3,4 So far, more and more synergistic or compound flame-retardant systems have been found, [5][6][7][8][9][10] including phosphorus-nitrogen, phosphorus-halogen, magnesium-aluminum, and other new compound flame retardant systems.…”