Flame retardancy and thermal stability of agricultural residue fiber‐reinforced polylactic acid: A Review

Abstract

Biocomposites containing natural fibers and biopolymers are an ideal choice for developing substantially biodegradable materials for different applications. Polylactic acid is a biopolymer produced from renewable resources and has drawn numerous interest in packaging, electrical, and automotive application in recent years. However, its potential application in both electrical and automotive industries is limited by its flame retardancy and thermal properties. One way to offset this challenge has been to incorporate natural or synthetic flame retardants in polylactic acid (PLA). The aim of this article is to review the trends in research and development of composites based on agricultural fibers and PLA biopolymers over the past decade. This article highlights recent advances in the fields of flame retardancy and thermal stability of agricultural fiber‐reinforced PLA. Typical fiber‐reinforced PLA processing techniques are mentioned. Over 75% of the studies reported that incorporation of agricultural fibers resulted in enhanced flame retardancy and thermal stability of fiber‐reinforced PLA. These properties are further enhanced with surface modifications on the agricultural fibers prior to use as reinforcement in fiber‐reinforced PLA. From this review it is clear that flame retardancy and thermal stability depends on the type and pretreatment method of the agricultural fibers used in developing fiber‐reinforced PLA. Further research and development is encouraged on the enhancement of the flame retardancy properties of agricultural fiber‐reinforced PLA, especially using agricultural fibers themselves as flame retardants as opposed to synthetic flame retardants that are typically used.

Durability of Biodegradable Polymer Nanocomposites

“…Thus, biopolyesters have emerged as a non-polar alternative for various applications that require contact with water, humidity and preservation of a sterile environment [ 31 ]. In addition, these polymers are often more thermally stable, melt-processed and easily modified with flame retardants for safety purposes [ 32 ]. While key characteristics of polymers are achieved with relatively high molecular weight.…”

Review on the performances, foaming and injection molding simulation of natural fiber composites

“…Flame-retardant mechanisms of materials can be divided into gaseous and condensed phase modes, and which can slow down the combustion process by physical or chemical ways. 97 When the condensed phase functions, flame retardants can be decomposed into nonvolatile substances or promote the material char formation during combustion processes, and produce a char layer on the materials surface. 98 When the flame retardants act in the gaseous phase, the noncombustible vapors or gases, like H 2 O, CO 2 , N 2 or NH 3 , are produced to dilute the oxygen concentration, effectively inhibiting the combustion behavior.…”

Flame Retardancy of Biobased Composites—Research Development

“…There are also numerous studies on the flame retardance behavior regarding other fibers (Table 2), such e.g., kenaf, hemp, wheat, sisal, bamboo, or alginate fibers [70][71][72]. PLA/kenaf fibers/recycled carbon with a cashew nut shell liquid -cardanol improved the thermal stability of kenaf; -the thermal stability of final composite was additionally improved by hybridization with recycled carbon (the flammability UL 90 HB test determines the flame retardancy property of all specimens) [73] PLA/kenaf fibers/phosphorus-based non-halogenated flame retardant (NP-100)…”

“…There are also numerous studies on the flame retardance behavior regarding other fibers ( Table 2 ), such e.g., kenaf, hemp, wheat, sisal, bamboo, or alginate fibers [ 70 , 71 , 72 ].…”