Metallized Phosphane–Ene Polymer Networks as Precursors for Ceramics with Excellent Shape Retention

Abstract

Our research group has reported the synthesis of phosphane−ene photopolymer networks, where the networks are composed of cross-linked tertiary alkyl phosphines. Taking advantage of the rich coordination chemistry of alkyl phosphines and the material's susceptibility to solution chemistry, we were able to generate Co, Al, and Ge macromolecular adducts. The metallized polymer networks can be pyrolyzed to make metaldoped carbon, commodity materials in the areas of battery, and fuel cell research. The polymer precursors can also be shaped by spin coating and lithography, before being metallized and pyrolyzed to give patterned ceramics, which display excellent shape retention of the original patterns.

Polymer networks functionalized with low‐valent phosphorus cations

“…The volatiles were removed in vacuo to give a colorless oil (2H), which displayed a P H vibration in the IR spectrum (ν P-H = 2280 cm À1 ; Figure S13). [21] Network 2H was subjected to a second hydrophosphination reaction with either 1-hexene or 1-octene initiated by AIBN at 60 C to convert primary and secondary phosphine sites to tertiary P-centres (Scheme 4). [21] After workup, the resulting colorless oil showed no P H stretches in the IR spectrum and only one singlet indicative of tertiary phosphine was observed in the 31 P NMR spectra for both 2 and 3 (δ P ≈ À31.5 ppm).…”

“…[21] Network 2H was subjected to a second hydrophosphination reaction with either 1-hexene or 1-octene initiated by AIBN at 60 C to convert primary and secondary phosphine sites to tertiary P-centres (Scheme 4). [21] After workup, the resulting colorless oil showed no P H stretches in the IR spectrum and only one singlet indicative of tertiary phosphine was observed in the 31 P NMR spectra for both 2 and 3 (δ P ≈ À31.5 ppm). The broadness of the endothermic transition centered at 0 C in the DSC plot for 2H is indicative of the mixture of 1 , 2 , and 3 phosphines in the material (Figure S15).…”

“…The volatiles were removed in vacuo to give a colorless oil ( 2H ), which displayed a PH vibration in the IR spectrum (ν P‑H = 2280 cm −1 ; Figure S13). [ 21 ]…”

“…We have reported the synthesis of phosphane-ene photopolymer networks, where the networks are composed of crosslinked tertiary alkyl phosphines that are insoluble, yet solvent swellable and amenable to solution-like chemistry and spectroscopy. [14,[19][20][21][22] We have observed that these phosphane-ene networks can be used as heterogeneous ligand scaffolds and can be functionalized with a variety of metallic Lewis acids, in particular stibino-phosphonium and stibino-bis(phosphonium) cations. [20][21][22][23] These Sb-based cations are fundamentally unique as small molecules, but when installed into a polymer, the physical and electronic properties of the material are substantively altered, simply by varying the degree of P substitution about Sb.…”

“…[14,[19][20][21][22] We have observed that these phosphane-ene networks can be used as heterogeneous ligand scaffolds and can be functionalized with a variety of metallic Lewis acids, in particular stibino-phosphonium and stibino-bis(phosphonium) cations. [20][21][22][23] These Sb-based cations are fundamentally unique as small molecules, but when installed into a polymer, the physical and electronic properties of the material are substantively altered, simply by varying the degree of P substitution about Sb. Inspired by this finding, we set out to create lighter P congeners of these materials and in this context, we present phosphinophosphonium cation-and triphosphenium cationfunctionalized polymer networks designed based on their established molecular analogues.…”