Preparation of DOPO‐derived magnesium phosphate whisker and its synergistic effect with ammonium polyphosphate on the flame retardancy and mechanical property of epoxy resin

Abstract

In this study, a magnesium phosphate whisker (DPM-H) was synthesized by the acid-base neutralization reaction between magnesium hydroxide and 10-hydroxy-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO-OH) at 120 C. A new synergistic intumescent flame retardant (IFR) for epoxy resin (EP), which was composed of DPM-H and ammonium polyphosphate (APP) was thoroughly studied. When the IFR loading was 8%, with the DPM-H to APP weight ratio at 1:7, the prepared flame-retardant EP (EPDA-2) passed the vertical burning tests (UL-94) V-0 rating and obtained the limiting oxygen index (LOI) value of 29.3%. Microscale combustion calorimetry (MCC) results showed that the total heat release (THR) of EPDA-2 reduced by 32.1% compared with pure EP. Meanwhile, the addition of DPM-H can partially solve the problem of the decrease of the EP mechanical property caused by the addition of APP. Compared with the flame-retardant EP with the 8% loading of APP, the impact strength of EPDA-2 increased 152.3%.

Selective Adsorption of Methyl Orange and Methylene Blue by Porous Carbon Material Prepared From Potassium Citrate

“…Adsorption isotherms are mainly used to analyze the adsorption behaviors between the adsorbent and the adsorbate. Many adsorption isotherms have been proposed from different perspectives; the commonly used models include the Langmuir adsorption isotherm model, the Freundlich adsorption isotherm model, and the Temkin adsorption isotherm model. ,,,− The Langmuir isotherm is on account of the monolayer adsorption theory; that is, there are a certain number of adsorption sites on the adsorbent surface, and each site can adsorb a molecule, so the surface adsorption is a monolayer. The formula is as follows: c normale q normale = 1 q m K L + 1 q normalm c e where q m (mg g –1 ) is the Langmuir monolayer adsorption capacity and K L (L mg –1 ) is the Langmuir adsorption constant.…”

“…The adsorbent is the pivotal factor in determining the adsorption treatment performance . A large number of adsorbents such as metal–organic frameworks (MOF), self-assembled nanostructures, porous polymer, layered double hydroxide, zeolite, and porous carbon have been developed for dye adsorption. − Duo et al prepared an iron-based metal–organic framework (MOF-235) to remove the Congo red (CR) and lemon yellow (LY) in the water . The adsorption capacities of the obtained MOF-235 for CR and LY were 1131 and 209 mg g –1 , respectively.…”

Potassium citrate-derived porous carbon with high CO2 capture and Congo red adsorption performance

“…Recently, more and more attention has been paid to the high value-added products prepared from biomassderived material [30][31][32]. Porous carbon adsorbent can be obtained from biomass-derived materials, such as coconut shell [33], lotus stem, maple leaf, garlic peel, and nutshell [34,35].…”

Application of the PAPP/MCA/APP intumescent flame retardant system in polypropylene

“…Meanwhile, because of the advantages of the simple preparation method and the high flame retardancy of IFRS, the development of IFRS has attracted much attention in recent years 23–28 . In the developed IFRS, flame retardants containing N and P elements have been widely used 29–32 . APP is a commonly used halogen‐free flame retardant containing N and P elements.…”

“…[23][24][25][26][27][28] In the developed IFRS, flame retardants containing N and P elements have been widely used. [29][30][31][32] APP is a commonly used halogen-free flame retardant containing N and P elements. During the combustion of APPcontaining polymer materials, phosphoric acid derivatives can be produced, which can catalyze the char formation process of polymer materials, leading to the improvement of the flame retardancy of polymer materials.…”