About

David Bergbreiter is a Professor at Texas A&M University in the College of Arts and Sciences, serving as the Director of the Organic Program within the Department of Chemistry. His research group explores new chemistry related to catalysis and polymer functionalization, utilizing synthetic organic chemistry tools to prepare functional oligomers or polymers. These materials are used to influence catalysis in environmentally benign ways or to functionalize polymers efficiently. His work often involves developing new separation chemistry that creatively uses polymers while retaining the reactivity of low molecular weight catalysts, ligands, or reagents. Bergbreiter's projects focus on fundamental research in synthesis and catalysis with practical relevance, particularly in addressing issues related to the recovery and reuse of expensive or toxic metals and catalysts, energy-intensive separation processes, and waste reduction. His research also includes designing solvent systems using soluble polymers, modifying existing polymers, and developing 'smart' polymers for water purification and other applications. Bergbreiter's educational background includes a B.S. from Michigan State University and a Ph.D. from the Massachusetts Institute of Technology. He has received numerous awards, including the Regents' Professor Award, the Presidential Professor for Teaching Excellence, and the Eppright University Professorship for Undergraduate Teaching Excellence.

Research topics

• Chemistry
• Organic chemistry
• Mathematics

Selected publications

• Microheterogeneous Polymeric Solvent Systems

  Liquids · 2025-09-08

  articleOpen accessSenior authorCorresponding

  This paper shows that low concentrations of either a low-molecular-weight or a recyclable polymeric cosolvent can be used to design recyclable, tunable alkane polymeric solvent systems. We have shown that dyes experience a microheterogeneous environment that is ca. 40–50% like that of a polar solvent with as little as 0.1 M added cosolvent. Dyes like Nile red or a polyisobutylene (PIB)-bound dansyl fluorophore both detected microheterogeneity in macrohomogeneous mixtures of heptane or a poly(α-olefin) (PAO) with 0.1–2.0 M added polar solvents. H-Bonding cosolvents have greater effects than cosolvents that only interact with dyes by dipole–dipole interactions. Microheterogeneity was also seen when a PIB-bound version of a low-molecular-weight solvent is used as the added polar cosolvent. These microheterogeneous environments can advantageously be used in synthetic and catalytic reactions. This was demonstrated in transesterification and SN2 chemistry. Reactions in PAO solutions polarized by 2 M added THF or by 0.5 M of a PIB-bound HMPA analog both had enhanced reactivity versus reactions in a PAO solution without added cosolvent. In the latter case, the catalyst, the PAO solvent, and the PIB-bound cosolvent were all fully recyclable.

  PublisherOA PDFDOI

• Sequestration of Dyes from Water into Poly(α-Olefins) Using Polyisobutylene Sequestering Agents

  Technologies · 2024-08-20

  articleOpen accessSenior authorCorresponding

  Trace concentrations of dyes are often present in textile wastewater streams and present a serious environmental problem. Thus, these dyes must be removed from wastewater either by degradation or sequestration prior to discharge of the wastewater into the environment. Existing processes to remove these wastewater contaminants include the use of solid sorbents to sequester dyes or the use of biochemical or chemical methods of dye degradation. However, these processes typically generate their own waste products, are not necessarily rapid because of the low dye concentration, and often use expensive or non-recyclable sequestrants or reagents. This paper describes a simple, recyclable, liquid–liquid extraction scheme where ionic dyes can be sequestered into poly(α-olefin) (PAO) solvent systems. The partitioning of anionic and cationic dyes from water into PAOs is facilitated by ionic PAO-phase anchored sequestering agents that are readily prepared from commercially available vinyl-terminated polyisobutylene (PIB). This is accomplished by a sequence of reactions involving hydroboration/oxidation, conversion of an alcohol into an iodide, and conversion of the resulting primary alkyl iodide into a cationic nitrogen derivative. The products of this synthetic sequence are cationic nitrogen iodide salts which serve as anionic sequestrants that are soluble in PAO. These studies showed that the resulting series of cationic PIB-bound cationic sequestering agents facilitated efficient extraction of anionic, azo, phthalein, and sulfonephthalein dyes from water into a hydrocarbon PAO phase. Since the hydrocarbon PAO phase is completely immiscible with water and the PIB derivatives are also insoluble in water, neither the sequestration solvent nor the sequestrants contaminate wastewater. The effectiveness and efficiency of these sequestrations were assayed by UV–visible spectroscopy. These spectroscopic studies showed that extraction efficiencies were in most cases >99%. These studies also involved procedures that allowed for the regeneration and recycling of these PAO sequestration systems. This allowed us to recycle the PAO solvent system for at least 10 sequential batch extractions where we sequestered sodium salts of methyl red and 4′,5′-dichlorofluorescein dyes from water with extraction efficiencies of >99%. These studies also showed that a PIB-bound derivative of the sodium salt of 1,1,1-trifluoromethylpentane-2,4-dione could be prepared from a PIB-bound carboxylic acid ester by a Claisen-like reaction and that the sodium salt of this β-diketone could be used to sequester cationic dyes from water. This PIB-bound anion rapidly and efficiently extracted >99% of methylene blue, malachite green, and safranine O from water based on UV–visible and 1H NMR spectroscopic assays.

  PublisherOA PDFDOI

• Applications of poly(α-olefin)s as solvents in organometallic chemistry

  Journal of Organometallic Chemistry · 2022-01-10 · 10 citations

  articleSenior authorCorresponding
  PublisherDOI

• Sequestration of Phenols from Water into Poly(α-olefins) Facilitated by Hydrogen Bonding Polyisobutylene Additives

  ACS ES&T Water · 2022-08-01 · 2 citations

  articleSenior authorCorresponding

  While hydrocarbon solvents such as alkanes are ineffective in extraction of polar substances such as phenols from water, polymeric alkanes such as poly(α-olefin)s (PAOs) when modified with phase-anchored hydrogen bond-accepting polyisobutylene (PIB) additives can be designed so that these hydrocarbon solvent systems efficiently extract many phenols from water. Phenols such as bisphenol-A (BPA), 4-chlorophenol, 2,4-dichlorophenol, 2-naphthol, and alkyl- or aryl-substituted phenols are sequestered from water with >95% efficiency. For example, using a PIB oligomer with imidazole as a terminal group as an additive at a concentration of 0.1 M in a PAO that is a hydrogenated trimer of 1-decene (PAO432), >99% of the BPA present in an aqueous solution of deionized water containing 200 mg of BPA/L of water is extracted into the PAO phase. With PIB-imidazole in PAO432 at 0.6 or 1.0 M, an array of other chlorinated, brominated, and alkylated phenols, which were typically initially present between 200 and 500 mg/L water, were additionally extracted with >95% efficiency. Using 0.3 M PIB-imidazole in PAO432, other bisphenols such as phenolphthalein and fluorescein at concentrations of ca. 3 mg/L in water could be reduced to concentrations of <20 or 2 μg/L, respectively. While very polar phenols with methoxy, hydroxy, and amino substituents are less efficiently extracted, most of these phenols could ultimately be extracted and sequestered with >80% efficiency. PAO432/PIB-imidazole phases that contain sequestered phenol can be recycled by mixing the PAO phase with solid NaOH. This regenerates the starting PAO432/PIB-imidazole mixture. Recycling of these nonvolatile PAO solvent systems for at least five cycles is described. Substituted imidazoles bound to PIB were also shown to be similarly effective sequestering agents for phenols.

  PublisherDOI

• Impact of Shell Composition on Dye Uptake by Capsules of Ionic Liquid

  Langmuir · 2022-10-31 · 11 citations

  article

  Encapsulation of ionic liquids (ILs) has been shown to be an effective technique to overcome slow mass transfer rates and handling difficulties that stem from the high viscosity of bulk ILs. These systems commonly rely on diffusion of small molecules through the encapsulating material (shell), into the IL core, and thus the composition of the shell impacts uptake performance. Herein, we report the impact of polymer shell composition on the uptake of the small molecule dye methyl red from water by encapsulated IL. Capsules with core of 1-hexyl-3-methylimidazolium bis(trifluorosulfonyl)imide ([Hmim][TFSI]) were prepared by interfacial polymerization in emulsions stabilized by graphene oxide (GO) nanosheets; the use of different diamines and diisocyanates gave capsule shells with polyureas that were all aliphatic, aliphatic/aromatic, and aliphatic/polar aprotic. These capsules were then added to aqueous solutions of methyl red at different pH values, and migration of the dye into the capsules was monitored by UV-vis spectroscopy, compared to the capsule shell alone. Regardless of the polymer identity, similar extents of dye uptake were observed (>90% at pH = 2), yet capsules with shells containing polyureas with polar aprotic linkages took longer to reach completion. These studies indicate that small changes in capsule shell composition can lead to different performance in small molecule uptake, giving insight into how to tailor shell composition for specific applications, such as solvent remediation and gas uptake.

  PublisherDOI

• Capsules of the Poly(α-olefin) PAO₄₃₂ for Removal of BTEX Contaminants from Water

  Industrial & Engineering Chemistry Research · 2021-09-29 · 17 citations

  article

  Poly(α-olefins) (PAOs) are nonvolatile and nontoxic liquid hydrocarbon oligomeric solvents with solubility properties similar to heptane. PAOs can be used in traditional liquid–liquid extractions, but handling difficulties arise due to the formation of emulsions. In this study, PAO432, a low viscosity PAO with a molar mass of 432 g/mol, is encapsulated in a polymer-based shell using a Pickering emulsion stabilized by graphene oxide nanosheets and interfacial polymerization. The capsules are spherical with a diameter of approximately 50 μm and are 70 wt % PAO432. We demonstrate that these capsules can remove different low molecular weight organic contaminants from water, specifically benzene, toluene, ethylbenzene, and p-xylene (BTEX). In suspension, capsules of PAO432 were able to remove 97% of benzene from a saturated water solution, and >93% removal was observed for all BTEX components. We also showed that passing a contaminated aqueous solution through a column packed with the capsules resulted in removal of the contaminant and collection of water as the eluent. Encapsulation of PAO thus removes the need for emulsification as with traditional liquid–liquid extractions, allows for a lower PAO432:water ratio to be used, and gives the opportunity to develop a continuous extraction system. The favorable properties also indicate that PAO432 capsules might be suitable for other applications, including removal of BTEX gases from air.

  PublisherDOI

• Fully recyclable Brønsted acid catalyst systems

  Green Chemistry · 2021 · 19 citations

  Senior authorCorresponding
  • Chemistry
  • Organic chemistry
  • Mathematics

  Polyisobutylene-bound sulfonic acid are effective homogeneous Brønsted acid catalysts and they and a poly(alpha-olefin) (PAO) solvent are readily recyclable with simple product removal by extraction or distillation.

  PublisherDOI

• Sequestration of phenols from water using poly-α-olefins with phase anchored polyisobutylene sequestering agents

  2020-04-06

  preprintSenior author

  Macromolecular Chemistry: The Second Century [Author Benefits](https://scimeetings.acs.org/?utm_source=pubs_content_marketing&utm_medium=website&utm_campaign=0320_MCF_NPI_Launch_Spring_Homepage&ref=pubs_content_marketing) [How to use SciMeetings](https://storage.googleapis.com/dl.morressier.com/acs/SciMeetings-ACSSpring2020-HowToGuide_M3020-Final.pdf) [Frequently Asked Questions](https://storage.googleapis.com/dl.morressier.com/acs/SciMtng_ACSNMSp2020_FAQ_M3120_Final.pdf)

  PublisherDOI

• Sequestration of phenols from water using poly-α-olefins with phase anchored polyisobutylene sequestering agents

  2020-04-06

  preprintSenior author

  Macromolecular Chemistry: The Second Century [Author Benefits](https://scimeetings.acs.org/?utm_source=pubs_content_marketing&utm_medium=website&utm_campaign=0320_MCF_NPI_Launch_Spring_Homepage&ref=pubs_content_marketing) [How to use SciMeetings](https://storage.googleapis.com/dl.morressier.com/acs/SciMeetings-ACSSpring2020-HowToGuide_M3020-Final.pdf) [Frequently Asked Questions](https://storage.googleapis.com/dl.morressier.com/acs/SciMtng_ACSNMSp2020_FAQ_M3120_Final.pdf)

  PublisherDOI

• Sequestration of phenols from water using poly-α-olefins with phase anchored polyisobutylene sequestering agents

  2020-04-06

  preprintSenior author

  Macromolecular Chemistry: The Second Century [Author Benefits](https://scimeetings.acs.org/?utm_source=pubs_content_marketing&utm_medium=website&utm_campaign=0320_MCF_NPI_Launch_Spring_Homepage&ref=pubs_content_marketing) [How to use SciMeetings](https://storage.googleapis.com/dl.morressier.com/acs/SciMeetings-ACSSpring2020-HowToGuide_M3020-Final.pdf) [Frequently Asked Questions](https://storage.googleapis.com/dl.morressier.com/acs/SciMtng_ACSNMSp2020_FAQ_M3120_Final.pdf)

  PublisherDOI

Recent grants

• SusChEM: Polymers as Solvents and Ligands in Sustainable Homogeneous Catalysis

  NSF · $475k · 2014–2018

• Solvation Studies of Responsive Polymers in Solution and at Surfaces

  NSF · $420k · 2009–2013

• Designing New Soluble Polymers to Facilitate Separations and Reactions

  NSF · $558k · 2005–2009

• Biphasic Catalysis Using Soluble Polymer Supports

  NSF · $420k · 2010–2014

Frequent coauthors

• Martin Newcomb

  University of Illinois Chicago

  45 shared

• Hassan S. Bazzi

  37 shared

• Yannan Liang

  Shanghai Institute of Technology

  22 shared

• Jakkrit Suriboot

  Texas A&M University

  22 shared

• James M. Killough

  College Station Medical Center

  18 shared

• Richard M. Crooks

  Antrim Area Hospital

  16 shared

• Tatyana Khamatnurova

  Halliburton (United States)

  15 shared

• Joseph H. Reibenspies

  13 shared

Education

• Ph.D., Chemistry

  Massachusetts Institute of Technology

  1974

• B.S., Chemistry

  Michigan State University

  1970

Awards & honors

• South Eastern Conference Faculty Achievement Award (2017)
• Regents' Professor Award (2016 – present)
• Student Led Award for Teaching Excellence
• Southwest Regional Award (2008)
• University-Level Association of Former Students Distinguishe…