Fabricating a partial wetting structure for improving the toughness of intumescent flame‐retardant HDPE

Abstract

Elastomer always exhibited poor efficiency for toughening flame-retardant polymer. In intumescent flameretardant HDPE, a novel multi-steps processing method was employed by Chang Lu and colleagues, to fabricate a partial wetting structure in which LLDPE-g-MAH phase with the sphere was dispersed at the interface. The partial wetting structure caused a remarkable improvement of the toughness of flameretardant HDPE with 2 wt% LLDPE-g-MAH. Its elongation at break and notched impact strength were 43% and 270% higher, respectively, than that of neat HDPE. The unique interface failure mode should be responsible for the high impact strength.ARTICLES 48474 Polybutylene terephthalate modified with dimer acid methyl ester derived from fatty acid methyl esters and its use as a hot-melt adhesive

A new bio‐based flame retardant simply synthesized: Improving the flame retardancy and thermal stability of low‐density polyethylene together with melamine cyanurate

“…From Figure 10a,d, it can be seen that pure LDPE and LDPE/MCA composite completely decompose during combustion and basically produce no residue, which explains why the two samples will release a lot of heat, smoke and toxic gases during combustion. When MHPA is added, LDPE/MHPA composites produce obvious residues after combustion, but these residues do not form a stable structure, and there are obvious cracks and voids on the surface, which means that the flame is very easy to penetrate into the interior during combustion, and the damaged carbon layer is also more likely to cause secondary combustion, which is consistent with the change rules of curves such as THR and TSP 29 . In addition, it can be seen from Figure 10e that only adding MHPA cannot produce expansion effect, so it is difficult to isolate the external flame and the distance between combustible gas and internal combustible, thus it is difficult to achieve thermal insulation and flame retardant effect.…”

“…After adding MCA, the internal structure of LDPE/MHPA/MCA composite changes significantly. From Figure 4c, it can be seen that many small particles appear on the fracture surface of LDPE/MHPA/MCA composite, and obvious cracks appear at the junction of these particles and LDPE, which indicates that the compatibility between MCA and LDPE is poor, forming an obvious island structure 29 . MCA is an inorganic and organic LDPE with poor compatibility, which causes this phenomenon.…”

“…From Figure 4c, it can be seen that many small particles appear on the fracture surface of LDPE/MHPA/MCA composite, and obvious cracks appear at the junction of these particles and LDPE, which indicates that the compatibility between MCA and LDPE is poor, forming an obvious island structure. 29 MCA is an inorganic and organic LDPE with poor compatibility, which causes this phenomenon. As the MCA content increases, the number of small particles on the fracture surface of the LDPE/ MCA composite increases, as does the number of voids and cracks, and thus the stability of the internal structure is compromised.…”

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

“…In the previous research, some additives 23 showed promising flame-retardancy while mechanical properties of composites such as elongation at break were severely influenced. 3,24,25 It was due to the wide difference between the structure of the polymer and its flameretardant additives. Based on this situation, herein, we investigated a novel method in which the flame-retardant group was grafted directly to the polymer and then mixed it with the pure high density polyethylene (HDPE) matrix at the commonly used percent of 15% in industry, expecting an enhancement in the compatibility between them.…”

Investigation of novel intumescent flame retardant low‐density polyethylene based on SiO2@MAPP and double pentaerythritol

“…It is one of the hotspots in the field of inorganic phosphorus flame retardants. [19][20][21] However, the compatibility between IFR and polymer is poor, which makes the mechanical properties and flame retardancy of polymer decline. Moreover, the IFR is easy to absorb moisture, which will result in the water resistance decrease of flame retardant polymer.…”