A novel grafted polyethylene with diphenyl phosphoryl group: Improved flame retardancy and favorable compatibility

Abstract

A novel phosphorous/benzene-containing flame-retardant diphenyl phosphoryl polyethylene (PEP) is synthesized from ethylene vinyl acetate (EVA) copolymer with two steps reactions and its chemical structure is characterized by Fourier transform infrared and nuclear magnetic resonance spectroscopies. The grafted molecular dispersion is calculated by gel permeation chromatography and the phase transition is analyzed by differential scanning calorimetry. And results show its promising processability potential. High density polyethylene (HDPE) composite containing 15 wt% PEP is prepared by melt blending, and its fire performance and thermal behaviors are investigated in terms of limiting oxygen index (LOI), vertical burning (UL-94) and thermogravimetric analysis. There is a 16% increase to 20.2 in the LOI value of PEP, while it fails the UL-94 test. The char morphology is characterized by scanning electronic microscopy and observed multi-layered intumescent residue char effectively reduces the transfer of heat and oxygen. The major degradation is quantitively analyzed by the Flynn-Wall-Ozawa method. The results demonstrate that there is a catalytic effect by the phosphorous substance in char formation. Finally, the mechanical properties tests show that the loss due to the addition is small, which signifies the good compatibility between the pure HDPE and the grafted addition.

Synthesis, properties and applications of well‐designed hybrid polymers based on polyhedral oligomeric silsesquioxane

“…Actually, the derivatives described here refer to molecules with POSS as the core, and POSS as repeated units or branched chains are not in this category. Some traditional organic synthetic methods are reviewed here based on functionalized POSS deviations such as esterification, amidation, epoxy addition, hydrosilylation etc 19 . Besides, synthetic methods based on click chemistry such as thiol‐ene and azide–alkyne have been widely used in recent years due to their high yield and high activity 52 .…”

“…Functional POSS derivatives, integrating many advanced properties, can be obtained by active chemistry, such as living polymerization and click chemistry 18–20 . The functional group attached to the POSS arm can be a molecule or macromolecule.…”

Preparation and characterization of poly(ethylene‐co‐vinyl acetate)/high‐density polyethylene/aluminum hydroxide/clay composites by electron beam irradiation

“…However, pristine PETPs have several disadvantages, such as flammability, deterioration of mechanical properties at high temperatures, low decomposition temperature, and poor compatibility. To address these drawbacks, blending and/or crosslinking with functional additives and fillers is generally required 4–7 …”

Progress in the self-assembly of organic/inorganic polyhedral oligomeric silsesquioxane (POSS) hybrids

“…, anionic, cationic, ring opening polymerization (ROP), nitroxide-mediated polymerization (NMP), reversible addition-fragmentation chain transfer (RAFT), atom transfer radical polymerization (ATRP)] and click chemistry. 97–103 For example, we used a chain-end-tethered mono-functionalized chloride-POSS as a macroinitiator to prepare a poly(methyl methacrylate)– block –POSS (PMMA- b -POSS) hybrid through ATRP [Fig. 3(a)].…”