Improved Mechanical Properties and Flame Retardancy of Wood/PLA All‐Degradable Biocomposites with Novel Lignin‐Based Flame Retardant and TGIC

Abstract

In this study, a type of all‐degradable flame retardant wood/poly(lactic acid) (PLA) biocomposite (FPW) with low cost and excellent mechanical properties is prepared and studied. A novel lignin‐based phosphorus‐containing flame retardant (LMD) is synthesized first. PLA, wood powder, poly(butyleneadipate‐co‐terephthalate), triglycidyl isocyanurate (TGIC), and LMD are then melt‐blended to prepare FPW. The limiting oxygen index value of PLAF25L15‐4T (25% of L15MD and 4% of TGIC) reaches 28.6%. Furthermore, the residue at 700 °C is up to 31.3%, which apparently helps to increase the flame retardancy of FPW. Its tensile strength is as high as 48.7 MPa. The interfacial compatibilization is much improved as proved by scanning electron microscopy observation. This should be due to the in situ interfacial reaction between PLA, wood, and TGIC, and the lignin component both in wood and LMD. The obtained PLA biocomposite with improved mechanical and flame retardant properties is promising for its wide applications.

Multifunctional lignin-based nanocomposites and nanohybrids

“…Progress in lignin-based flame retardants was reviewed by Yang et al 415 There is a renewed interest in this research area as indicated by the studies published since their recent review. 416,417 To contribute to the development of scalable materials, synthesis of lignin-based flame retardants should increasingly rely on green and sustainable chemistry. In particular, the number of synthetic steps should be minimized along with the solvents and reagents used, and the proportion of lignin in the multicomponent flame retardants should be as high as possible.…”

“…The majority of these lignin-based fire-retardant polymers are P-lignin, 423 N-lignin, 424 and PN-lignins. 417,425 There are also works incorporating siloxane, 426 and boron 427 in lignin-based fire retardant materials. Though lignin itself has been found to exhibit intumescent behaviour, 428 mainly chemically modified lignins have been evaluated in intumescent coating systems that swell upon thermal exposure and form a protective carbonaceous char layer.…”

Construction of crosslinking network structures by addingZnOandADRin intumescent flame retardantPLAcomposites

“…In addition, the fibers after modification were added into the PLA matrix as a flame retardant component in some literatures, which could effectively improve the comprehensive performance of PLA. For example, Hu 48 synthesized a novel lignin‐based phosphorus‐containing flame retardant (LMD) and applied in PLA system combined with triglycidylisocyanurate (TGIC). Results showed the interfacial compatibilization was improved due to the in situ interfacial reaction between different components, which led to the increased mechanical properties.…”

Stereocomplex Crystallization Induced Significant Improvement in Transparency and Stiffness–Toughness Performance of Core‐Shell Rubber Nanoparticles Toughened Poly(l‐lactide) Blends

“…[ 6–8 ] In this condition, poly( l ‐lactide) (PLLA), as one typical member of bio‐based and biodegradable polymers, has gained a great development opportunity due to its good biocompatible, optical, and mechanical properties. [ 9–12 ] Unfortunately, the further development and industrial applications of PLLA are still impeded by its poor thermal stability, gas barrier properties, especially brittleness until now. [ 13–16 ] Using rubber particles to toughen PLLA has proved to be a simple and economical method.…”