Design and Synthesis of PET‐Based Copolyesters with Flame‐Retardant and Antidripping Performance

Abstract

Poly(ethylene terephthalate) (PET) is a fiber‐forming polymer with the largest output and widest usage. Its flame retardation is well‐achieved via a mechanism of promoting the melt dripping while ignited. However, the melt dripping leads to secondary damage and an immediate empyrosis during fire. How to address the contradiction between the flame retardation and the melt‐dripping behavior of PET via an inherent flame‐retardant approach becomes a real challenge. This feature article highlights the design and synthesis of novel PET‐based copolyesters with flame‐retardant and antidripping performance. Three approaches are used to design these copolyesters: “ionic aggregation,” “smart self‐cross‐linking,” and “rearrangement at high temperatures.” Some new conceptions are proposed accordingly. The synthesis, structure characterization, and properties of those copolyesters are discussed together with the ongoing challenges and limitations at this frontier.

A macromolecular halogen‐free flame retardant and its effect on the properties of thermoplastic polyesters

“…Some known phosphorus compounds have a lower performance, eg, macromolecular phosphine oxides and oligomeric thiophenylphosphonates . Others seem to have a similar efficiency, among them derivatives of DOPO and phosphinic acid, as well as systems which contain metal phosphinates . Some systems, which combine phosphorus with other active elements (synergists), even perform better .…”

“…16,26 Others seem to have a similar efficiency, among them derivatives of DOPO and phosphinic acid, as well as systems which contain metal phosphinates. [27][28][29] Some systems, which combine phosphorus with other active elements (synergists), even perform better. 13 Here, the advantages of the novel flame retardant are its macromolecular structure, which prevents unwanted release into the environment, and its low effect on the thermal and mechanical properties of the matrix polymer.…”

Polyphosphazene microspheres modified with transition metal hydroxystannate for enhancing the flame retardancy of polyethylene terephthalate

“…However, high flammability and severe melt dripping limit its application in many fields . Therefore, many methods, such as copolymerization, flame‐retardant coatings, and melt blending have been developed to solve this problem, of which melt blending is most commonly used . Traditional halogen‐based flame retardants have gradually been unacceptable because of their harmful hydrogen halides release, and current flame retardant development mainly focuses on halogen‐free flame retardant .…”

Improving the flame retardancy of waterborne polyurethanes based on the synergistic effect of P–N flame retardants and a Schiff base

“…Although these ame retardants were shown to signicantly enhance the re resistance of a matrix with a high LOI, their limited anti-dripping property is a highly dangerous problem, as it has the potential to lead to secondary re, re spread and immediate empyrosis. 21,22 Schiff base, which is also known as azomethine or imine, is made from the condensation reactions of ketones or aldehydes with primary. Owing to the excellent rigidity of azomethines, Schiff base compounds have been seen as effective in improving the thermal properties of polymers.…”