Ionic Liquids as Delaminating Agents of Layered Double Hydroxide during In-Situ Synthesis of Poly (Butylene Adipate-co-Terephthalate) Nanocomposites

Abstract

Currently, highly demanded biodegradable or bio-sourced plastics exhibit inherent drawbacks due to their limited processability and end-use properties (barrier, mechanical, etc.). To overcome all of these shortcomings, the incorporation of lamellar inorganic particles, such as layered double hydroxides (LDH) seems to be appropriate. However, LDH delamination and homogenous dispersion in a polymer matrix without use of harmful solvents, remains a challenging issue, which explains why LDH-based polymer nanocomposites have not been scaled-up yet. In this work, LDH with intercalated ionic liquid (IL) anions were synthesized by a direct co-precipitation method in the presence of phosphonium IL and subsequently used as functional nanofillers for in-situ preparation of poly (butylene adipate-co-terephthalate) (PBAT) nanocomposites. The intercalated IL-anions promoted LDH swelling in monomers and LDH delamination during the course of in-situ polycondensation, which led to the production of PBAT/LDH nanocomposites with intercalated and exfoliated morphology containing well-dispersed LDH nanoplatelets. The prepared nanocomposite films showed improved water vapor permeability and mechanical properties and slightly increased crystallization degree and therefore can be considered excellent candidates for food packaging applications.

Hydrophobic nanocomposites of PBAT with Cl‐fn‐POSS nanofiller as compostable food packaging films

“…[ 24 ] Nanofillers can enhance the thermal, mechanical, and barrier performance significantly in polymers. In this context, PBAT has been reinforced with many fillers, such as cellulose nanocrystals, [ 29 ] bark flour of plane tree, [ 30 ] starch, [ 31 ] montmorillonites, [ 32 ] layered double hydroxides, [ 33 ] agar, [ 34 ] date seed powder, [ 35 ] silica, GO, CNT, [ 36 ] and so on. Among the reported fillers, some are insoluble with poor compatibility with the polymer matrix, which might be due to lack of active functional groups that can interact with the polymer backbone.…”

Effects of Immobilized Ionic Liquid on Properties of Biodegradable Polycaprolactone/LDH Nanocomposites Prepared by In Situ Polymerization and Melt-Blending Techniques

“…Generally, the LDH addition leads to an improvement in material stiffness (the increased Young modulus, E) resulting from enhanced rigidity, which is induced by the incorporation of nanofiller to polymer matrix [ 4 ]. Herein, the Young’s modulus of the PCL nanocomposite with non-modified C-Ca/Al (MB-PCL + C-Ca/Al) prepared by melt-blending was decreased by adding 1 wt % of LDH nanofillers.…”

“…Therefore, recent research has been focused on investigation of polyester nanocomposites prepared by ring opening polymerization (ROP) of cyclic monomers such as ε- caprolactone ( ε CL), lactide (LA), glycolide (GA), and their copolymers, or condensation copolyesters (e.g. poly(butylene adipate-co-terephthalate, PBAT) with natural or synthetic clays like montmorillonite (MMT), hydrotalcite or layered double hydroxides (LDH) [ 1 , 2 , 3 , 4 ]. In comparison with conventional polymer composites, the small content of nanoclays insignificantly or only slightly alters processing parameters (e.g., viscosity, density, melting, and glass transition temperature), but efficiently improves the mechanical, flame retardant, and barrier properties of final polymer materials [ 5 ].…”

Layered Double Hydroxide (MgFeAl-LDH)-Based Polypropylene (PP) Nanocomposite: Mechanical Properties and Thermal Degradation

“…LDHs have been used as acid scavengers [ 17 ], in the pharmaceutical industry [ 18 ], as antioxidants [ 19 ], in biomedical applications [ 20 , 21 , 22 , 23 ], as UV-Vis absorption materials [ 12 , 24 , 25 , 26 ], in photovoltaic and solar cells [ 26 ], in supercapacitors [ 27 ], in sensors [ 28 ], in wastewater treatments [ 29 ], as precursors for photocatalytic materials [ 30 , 31 ], as catalysts [ 18 , 32 ], as stabilizers in polymers [ 33 , 34 ] and as flame retardants for polymers [ 35 , 36 , 37 , 38 ]. LDHs can be used for different purposes—as coolants and in producing diluents for flammable gas [ 39 ], as flame retardants providing resistance to ignition [ 40 ], or they can provide an alternate way of combustion with a slower rate of flame spread and can reduce the quantity of smoke [ 18 , 40 ].…”