Flame‐retardant cyanate ester resin with suppressed toxic volatiles based on environmentally friendly halloysite nanotube/graphene oxide hybrid

Abstract

Development of high‐performance thermosetting resins by adding environmentally friendly flame retardant to heat‐resistant resins without deteriorating their outstanding thermal stability is an important research direction. Here, a unique hybrid (GHNT) consisting of graphene oxide (GO) and halloysite nanotubes (HNT) was synthesized, and then a series of composites based on cyanate ester (CE) resin were fabricated. The effects of GHNT on the heat resistance, flame retardancy, and smoke suppression of GHNT/CE composites were intensively investigated. The GHNT/CE composite with 5.0 wt % GHNT not only has about 15.1 °C higher initial degradation temperature, but also shows 54.6% or 37.9% lower peak heat release rate or maximum smoke density than CE resin. These results clearly demonstrate that GHNT is not the simple combination of GO and HNT; instead, it obviously shows positive synergistic effects in simultaneously improving the flame retardancy and thermal resistance of CE resin. The improved flame retardancy could be attributed to condensed‐phase mechanisms, including increasing char yield, building a dense char layer, and free radical scavenging. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46587.

Phosphorus‐free boron nitride/cerium oxide hybrid: A synergistic flame retardant and smoke suppressant for thermally resistant cyanate ester resin

“…Based on Raman spectra of char residues, the intensity ratio ( I G / I D ) of D peak (1344 cm −1 ) to G peak (1595 cm −1 ) is a key indicator for evaluating the graphitization degree of char residue, higher I G / I D means higher graphitization level of char residue . 2BN@CeO 2 /BCy has an I G / I D of 0.39, higher than those of BCy (0.31) and 2(BN + CeO 2 )/BCy (0.35), proving that BN@CeO 2 is conducive to improve both compactness and graphitization degree of char residue.…”

“…Because all samples tested had same sizes, morphologies and weights, the intensities of absorption peaks in 3D spectra reflect the amounts of degradation products . As shown in Figures and , the majority of pyrolysis products of BCy resin are organic gaseous combustibles such as various hydrocarbons (3050 cm −1 ), aromatic compounds (1596, 1510 cm −1 ), and aliphatic compounds (1259, 1180 cm −1 ); besides, which also contain a small loadings of CO 2 (2283, 2250 cm −1 ) and water (3656 cm −1 ) . 2BN@CeO 2 /BCy has greatly reduced gas phase products (mainly CO 2 , aromatic compounds and aliphatic compounds).…”

“…Our research aims at developing a phosphorus‐free method to prepare heat‐resisting resins having high flame retardancy and smoke suppression. Cyanate ester (BCy) resin is thought to be suitable basic resin owing to its important applications in lots of leading‐edge fields . This paper gives the first report on phosphorus‐free hybrid (denoted as BN@CeO 2 ) consisting of BN nanosheet and CeO 2 , which is proved to be a synergistic flame retardant and smoke suppressant for thermally resistant BCy resin.…”

Halloysite Nanotubes as an Additive to Ensure Enhanced Characteristics of Cold-Curing Epoxy Resins under Fire Conditions

“…A similar decreasing trend in peak maximum is also observed in the case of Oxidation-2 ( T max 2 ), where a noticeable but not very significant decrease in the maximum temperature occurs. This decrease in temperature T max 2 is most likely due to the dehydroxylation of the HNTs, which occurs at a maximum temperature of approximately 482 C [ 36 ] The dehydroxylation of the HNTs slightly shifts the temperature range of the main thermo-oxidation of the polymer matrix (Oxidation-2) with an increasing weight fraction of HNTs and, at the same time, suppresses this intensive process (see a detailed discussion on the barrier effect in [ 49 ] and the dilution of degradation products in [ 50 ]).…”

Improved flame retardant of intumescent flame retardant flame-retarded high density polyethylene with fullerene decorated by iron compound

“…Therefore, cutting off free radical chain reaction can inhibit the degradation and combustion process. For example, rare earth compounds [1,2], graphene [3] and hindered amines [4][5][6] were added to polyolefin to capture the free radicals and terminate the chain reaction. Fullerene (C 60 ) also has positive effects on the thermal stability and flame retardancy of polymers due to its free radical trapping ability.…”