(182f) Fabrication of Ti3C2-Polyacrylate Nanocomposites By High-Temperature Free-Radical Polymerization

MXenes are a family of nanomaterials that are hydrophilic and electrically- and thermally conductive and have surface functional groups such as hydroxyl, oxygen, chlorine, and fluorine. Similar to graphene oxide and clay, MXenes have layered structures and possess excellent antibacterial properties and high light-to-heat conversion efficiency [1, 2].

Spontaneous high-temperature (>140°C) free-radical polymerization of alkyl acrylate monomers has several appealing features [3-5]. First, the polymerization does not require any conventional initiator. Second, it results in the production of low average-molecular-weight polymers due to the more dominating role of polymerization reactions such as beta-scission and chain transfer to monomer at high temperatures. Third, it is versatile; it can be utilized to synthesize homopolymers and copolymers from monomers with an unsaturated carbon double bond. Low average-molecular-weight polymers have low solution viscosity. The addition of a 2-dimensional (2D) nano-filler such as Ti₃C₂ MXene to a reacting monomer leads to viscosity buildup, particularly at a high filler loading. In view of these, high-temperature free-radical polymerization is an attractive method for the in-site synthesis of nanocomposites.

In this work, we study the fabrication of Ti₃C₂-poly-alkyl-acrylate nanocomposites using (a) in-situ high-temperature polymerization of several alkyl acrylate monomers (including n-butyl acrylate) in the presence of Ti₃C₂ MXene and (b) the pristine MXene is replaced by a surface-modified MXene containing methacrylate groups. The prepared nanocomposites are characterized using a Scanning electron microscope, X-ray photoelectron spectroscopy, X-ray Diffraction, and Fourier-transform infrared spectroscopy. The effects of polymerization conditions and monomer type on nanocomposite properties (such as conductivity, thermal stability, and mechanical properties) are investigated.

Keywords: Ti₃C₂ MXene, Alkyl acrylates, Free-radical polymerization

References

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