The Preparation and Characterization of Polylactic Acid Composites with Chitin-Based Intumescent Flame Retardants

In this work, a novel intumescent flame retardant (IFR) system was fabricated by the introduction of chitin as a green charring agent, ammonium polyphosphate (APP) as the acid source, and melamine (MEL) as the gas source. The obtained chitin-based IFR was then incorporated into a polylactic acid (PLA) matrix using melt compounding. The fire resistance of PLA/chitin composites was investigated via the limiting oxygen index (LOI), UL-94 vertical burning, and cone calorimeter (CONE) tests. The results demonstrated that the combination of 10%APP, 5%chitin and 5%MEL could result in a 26.0% LOI, a V-0 rating after UL and a 51.2% reduction in the peak heat release rate during the CONE test. Based on the mechanism analysis from both the morphology and the chemical structure of the char, it was suggested that chitin was a promising candidate as a charring agent for chitin reacted with APP and MEL with the formation of an intumescent layer on the surface.

Synthesis of a Triazine-Based Hyper Branched Macromolecule Charring Agent and its Effect on Flame-Retardant Thermoplastic Polyester Elastomer to Improve Anti-Dripping

A triazine-based charring agent (CDS) was synthesized and combined with diethyl aluminum hypophosphite (AlPi) to develop an intumescent flame retardant (IFR) system to improve thermoplastic polyester elastomer (TPEE) anti-dripping. The results showed that the limiting oxygen index (LOI) of the TPEE/15AlPi/5CDS composite reached 30.2%, and it passed the V-0 test in vertical combustion (UL-94). The results of thermogravimetric analysis (TGA) showed that CDS had good thermal stability and high char residue (50.8wt%) at 700°C. And when combined with AlPi added to TPEE, which can improve its char residue ranges from 1.68wt% to 23.52wt%. The structure evolution during the heating process was studied by heating infrared spectroscopy (IR), and the morphology and chemical structure of char residues were studied by scanning electron microscope (SEM) and laser Raman spectroscopy (LRS). The high-efficiency flame-retardant TPEE composite formed a continuous, dense and porous char layer containing triazine ring and aromatic ring structure after combustion.

The production of flame retardant paper with DOPO

Flame retardant property to paper increases the use of paper and the value of paper products. The flame retardant property was achieved by the addition of an organophosphorus agent to the paper. A great deal of research has been done on 9,10-Dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) derivatives as flame retardants. To apply the flame retardant property in condensed phase, DOPO derivative materials are generally used as an acid source for intumescent flame retardants to promote dehydration and carbonization of the charring agent to form a continuous layer of carbon. In this study, In order to prepare a flame retardant paper coating, DOPO derivative was synthesized with 3-aminophenyl sulfone, and benzaldehyde reaction and the chemical structure of DOPO is illuminated by ATR-FTIR then paper was coating with a flame retardant coating formulation ingredient with DOPO. The paper’s properties were investigated. Surface energy of coated papers and contact angles were determined with goniometer. Printability parameters such as color, gloss, surface tension were examined. The results the study DOPO added paper coatings improve the paper flame retardancy.