arrow_circle_up

Reimagining the life cycle of polymeric materials.

Advancing materials science and synthesis.

Based in the Frick Chemistry Laboratory at Princeton University, the Stache Lab integrates diverse chemistry disciplines, including organic chemistry, photochemistry, inorganic materials, and polymer chemistry, to pioneer advancements in materials science and synthesis.

arrow_circle_left arrow_circle_right
●○○

Sustainable polymer chemistry via photothermal conversion.

We are developing synthetic strategies to degrade, upcycle, and chemically recycle commercial polymers. Our primary approach employs a light-to-heat conversion strategy (photothermal conversion), to produce intense thermal gradients capable of depolymerizing commercial plastics.

arrow_circle_left arrow_circle_right
○●○

Development of novel polymerization techniques and degradable polymers.

Commodity plastics are frequently produced without degradation in mind. We aim to develop polymers with degradable moieties readily incorporated, and push the frontiers of polymerization methods to access these polymers more readily and efficiently.

arrow_circle_left arrow_circle_right
○○●

Organic synthesis via photothermal conversion.

We are exploring photothermal conversion as a general strategy for organic synthesis. Photon-mediated chemical processes offer a pathway to create complex, biologically significant compounds, a critical pursuit within the pharmaceutical and agrochemical industry.

Recent publications.

  • Selective poly(vinyl ether) upcycling via photooxidative degradation with visible light

    Darren L. Langer, Sewon Oh, Erin E. Stache

    Chem. Sci. 2024, Advance Article

    Publication Abstract

    Poly(vinyl ethers) (PVEs) have many applications, such as adhesives, lubricants, and anticorrosive agents, thanks to their elastic, nonirritating, and chemically inert properties. The recycling of PVEs remains largely underexplored, and current methods lack generality towards other polymer classes. Thus, the chemical upcycling of PVE into small molecule feedstocks would provide an alternative approach to combat these current issues. Here, we report a visible light-mediated method of upcycling poly(isobutyl vinyl ether) (PIBVE) into small molecules via photooxidative degradation using chlorine or bromine radicals. PIBVE can be degraded to low molecular weight oligomers within 2 h, producing good yields of alcohols, aldehydes, and carboxylic acids. Mechanistic studies suggest that hydrogen atom transfer (HAT) from the backbone or the side chain leads to small molecule generation via oxidative cleavages. Additionally, this protocol was applied to a copolymer of poly(methyl acrylate-co-isobutyl vinyl ether) to demonstrate the preference for the degradation of polymers bearing more electron-rich C–H bonds through a judicious choice of abstraction agent. Ultimately, we show that photooxidative degradation enables the selective chemical upcycling of PVEs as a method of plastic waste valorization.

  • Electrochemically-Driven Degradation

    Selective Electrocatalytic Degradation of Ether-Containing Polymers

    Jesse H. Hsu, Tyler E. Ball, Sewon Oh, Erin E. Stache, Brett P. Fors

    Angew. Chem. Int. Ed. 2023, e202316578

    Publication Abstract

    Leveraging electrochemistry to degrade robust polymeric materials has the potential to impact society’s growing issue of plastic waste. Herein, we develop an electrocatalytic oxidative degradation of polyethers and poly(vinyl ethers) via electrochemically mediated hydrogen atom transfer (HAT) followed by oxidative polymer degradation promoted by molecular oxygen. We investigated the selectivity and efficiency of this method, finding our conditions to be highly selective for polymers with hydridic, electron-rich C−H bonds. We leveraged this reactivity to degrade polyethers and poly(vinyl ethers) in the presence of polymethacrylates and polyacrylates with complete selectivity. Furthermore, this method made polyacrylates degradable by incorporation of ether units into the polymer backbone. We quantified degradation products, identifying up to 36 mol % of defined oxidation products, including acetic acid, formic acid, and acetaldehyde, and we extended this method to degrade a polyether-based polyurethane in a green solvent. This work demonstrates a facile, electrochemically-driven route to degrade polymers containing ether functionalities.

  • Vanadium-Catalyzed Upcycling of Non-Biodegradable Plastics

    From Trash to Treasure: Vanadium-Catalyzed Upcycling of Non-Biodegradable Plastics

    Hanning Jiang and Erin E. Stache

    Chem 2023 9, 9, 2373-2375

    Publication Abstract

    Managing plastic waste is a challenging and pressing problem. In this issue of Chem, Soo and co-workers valorize commercial plastics and post-consumer plastic waste into isolable products, including formic acid, acetic acid, and benzoic acid, through vanadium-catalyzed tandem C–H oxidation and C–C cleavage photoreactions.

The current Stache Lab team

Our team.

The Stache Lab is led by Principal Investigator, Erin Stache. Our research team comprises a group of exceptional post-doctoral associates and graduate students.

Stache Lab logo avatar

Saving the world with polymer chemistry.