Graphite Oxide as a Dehydrative Polymerization Catalyst: A One-Step Synthesis of Carbon-Reinforced Poly(phenylene methylene) Composites

Abstract

The synthesis and characterization of poly(phenylene methylene) (PPM) and carbon composites thereof are described. The materials were prepared using graphite oxide (GO), which was discovered to function in two distinct roles. First, the GO was found to facilitate the dehydrative polymerization of benzyl alcohol (BnOH) to form PPM. Second, the residual carbon from the GO catalyst, having undergone thermal deoxygenation during the polymerization reaction, served as a graphene-like additive in the resulting composite. While pure (i.e., additive-free) PPM was found to be mechanically compliant (E′ = 40 MPa), inclusion of 0.1 wt % GO in the starting reaction mixture improved the material’s mechanical properties significantly (E′ = 320 MPa). Homogeneous dispersion of the additive in the matrix was confirmed by powder X-ray diffraction (PXRD) analysis, Raman spectroscopy, and transmission electron microscopy (TEM). The carbon additive was separated from the PPM via trituration in dichloromethane, and the GO starting material (C:O ratio = 2.0:1; σ = 4.45 × 10–5 S m–1) was found to have undergone significant reduction during the polymerization reaction (C:O ratio = 12.3:1; σ = 801 S m–1). Moreover, the recovered carbon did not assemble into graphite-like aggregates, as determined by PXRD, Raman spectroscopy, and TEM, which indicated that the PPM matrix was able to effectively disperse the additive.

Poly(Phenylene Methylene): A Multifunctional Material for Thermally Stable, Hydrophobic, Fluorescent, Corrosion-Protective Coatings

“…The common aluminum alloy AA2024 (also designated as Al-2024, containing 4.3%-4.5% copper, 0.5%-0.6% manganese, 1.3%-1.5% magnesium and less than 0.5% of other elements) was Remarkably, in addition to hydrophobicity, PPM shows exceptionally high thermal stability [7][8][9][10][11][12][13] (onset of decomposition at 470 • C by thermogravimetric analysis under air atmosphere [4]). Further, PPM is structurally similar to phenol resins but possesses higher thermal stability [14].…”

“…This property was ascribed to homoconjugation, a rare phenomenon which can arise under certain geometrical conditions when conjugated π-orbital systems interact with each other, although they are separated by an electronically insulating group such as a methylene group [5,6], as illustrated for PPM in Figure 1b. Remarkably, in addition to hydrophobicity, PPM shows exceptionally high thermal stability [7][8][9][10][11][12][13] (onset of decomposition at 470 °C by thermogravimetric analysis under air atmosphere [4]). Further, PPM is structurally similar to phenol resins but possesses higher thermal stability [14].…”

Effects of Graphene Nanoplatelets and Reduced Graphene Oxide on Poly(lactic acid) and Plasticized Poly(lactic acid): A Comparative Study

“…There are a number of reasons for producing graphene-based polymer nanocomposites. The addition of a filler with such impressive mechanical properties is expected to lead to a significant improvement in the mechanical properties of the host polymer matrix [3,4].…”

Graphite oxide activated zeolite NaY: applications in alcohol dehydration

“…28,29 GO is an ideal candidate for use in solid acid catalysis due to its relatively low cost, heterogenous state, and ease of preparation. 30 The material is typically synthesized in one step by treating natural flake graphite with KMnO 4 in H 2 SO 4 at room temperature followed by filtration.…”