About

Christopher N. Bowman is a Distinguished Professor and Clinical Professor of Restorative Dentistry at the University of Colorado Boulder, where he also holds the James M & Catherine Patten Chair in Chemical Engineering. His research primarily focuses on the investigation of the formation, structure, and properties of cross-linked polymeric materials, especially those formed through photopolymerization reactions. His group develops new materials and mechanisms for applications including biomaterials, microfluidic devices, dental restorations, liquid crystal displays, nanotechnology, and high technology. Bowman’s work involves a multifaceted approach that includes experimental characterization, modeling of polymerization kinetics, development of new monomers, and the creation of innovative photopolymerization techniques such as living radical and thiol-ene polymerizations. His research also extends to micro- and nanotechnology, where he develops polymer-liquid crystal composites, microfluidic devices, and surface patterning techniques for higher resolution lithography. With a background that includes a B.S. and Ph.D. from Purdue University, Bowman has received numerous awards and honors, including election to the National Academy of Engineering and the National Academy of Medicine, reflecting his significant contributions to the field of chemical and biological engineering.

Research topics

• Materials science
• Composite material
• Chemistry
• Computer Science
• Organic chemistry
• Nanotechnology
• Polymer science
• Polymer chemistry
• Physics
• Engineering physics
• History
• Engineering
• Optoelectronics
• Optics

Selected publications

• High-Refractive-Index Halogenated Urethane Acrylates in Polyurethane for 2-Stage Material Applications

  ACS Applied Polymer Materials · 2026-03-17

  articleOpen access

  High-refractive-index (HRI) monomers swollen in a rubbery host matrix to form 2-stage composite materials play a crucial role in modern optics applications and are constantly being redesigned to produce enhanced material properties. To aid in this effort, we report the synthesis of two HRI halogenated acrylate monomers and characterize their affinity for high-spatial-frequency photopatterning when swollen in a polyurethane matrix. Through refractive index measurements and high-resolution photopatterning, we show that these 2-stage films support submicrometer spatial frequencies with refractive index modulation n1 on the order of 0.01 and change in index upon polymerization Δn of 0.0023. Photopolymerization kinetics from FTIR fit a three-species kinetic model, where the dependence of the polymerization rate on incident light intensity reveals that the dominant termination kinetics in these 2-stage films is unimolecular termination, as opposed to the standard bimolecular. Critically, we show that photopatterning does not induce undesirable optical or mechanical properties such as haze, discoloration, stiffening of the films, or increased dispersion, making these materials suitable for photopatterning applications. High-fidelity holographic diffraction gratings and 2D photo-patterns with micron-scale features are presented to show proof of concept.

  PublisherDOI

• Preparation of Degradable Polymers Containing Tunable Ratios of Dithioacetals and Disulfides via Mixed Mode Polymerization

  Angewandte Chemie International Edition · 2025-08-21 · 3 citations

  articleSenior authorCorresponding

  Degradable polymers hold promise for their recyclability and their potential to facilitate the transition toward a circular economy of plastics. As such, a consecutive di-SN2 reaction between dithiols and polyhalogenated compounds was used to produce degradable polymers with tunable amounts of redox-enabled dithioacetal and disulfide linkages. The reaction employed bases of varying strengths and different thiol types, allowing for control over molecular weights ranging from <1 kDa to 16 kDa, with tunable degrees of polymerization ranging from 3 to over 75. The ratio of dithioacetals to disulfides was adjusted by manipulating the concentration of the methylene source, enabling the formation of polymers with up to 100% disulfide linkages or up to 93% dithioacetal linkages. This tunability resulted in polymers with multiple redox degradation pathways, capable of being degraded by either reduction or oxidation. Vinyl ether functionalized, telechelic oligomers were used as crosslinkers in network formation, yielding materials with multiple degradation pathways. This di-SN2 approach provides a promising and straightforward method for creating materials with tailored degradation characteristics.

  PublisherDOI

• Design and Synthesis of Hydrolytically Degradable PEG Carbamate, Carbonate, and Ester Derivatives to Induce Reversible Biostasis

  Biomacromolecules · 2025-02-25 · 5 citations

  articleSenior authorCorresponding

  Control over network chemistry and connectivity of hydrogels is critical for the generation of tunable material properties, including material degradation for applications such as tissue scaffolding and drug delivery. Here, the degradation of hydrogels employing different hydrolytically cleavable groups including benzamide and syringic acid-derived carbamates, kojic acid-derived carbonates, and kojic acid-derived esters under physiological conditions was studied. Tunability of the hydrogel network degradation was demonstrated by varying the hydrolytically degradable moiety, macromer functionality, and copolymerization with hydrolytically stable macromers. These hydrolytically labile macromers were introduced and cross-linked intracellularly to induce transient cellular quiescence in MCF10A cells, resulting in a highly tunable degradation mechanism that is shown to be capable of inducing reversible biostasis of cells with 60% of cells treated with the carbonate macromer returning to their proliferative state and rebounding in translational activity after 72 h, while the biological activity of the carbamate macromer-treated cells remained suppressed.

  PublisherDOI

• 1,2-Dithiolane/yne photopolymerizations to generate high refractive index polymers

  Polymer Chemistry · 2025-01-01 · 6 citations

  articleOpen accessSenior authorCorresponding

  Photoinitiated copolymerization of dithiolanes and alkynes results in copolymers with high refractive indices. Transmission holography performed via this reaction results in stable, high diffraction efficiency gratings with low haze, birefringence.

  PublisherOA PDFDOI

• Multifunctional dithiolane monomers for multi-scale, recyclable light-driven additive manufacturing

  Polymer Chemistry · 2025-01-01 · 8 citations

  articleOpen accessSenior authorCorresponding

  In this work, we develop a tetrafunctional monomer incorporating 1,2-dithiolanes as the reactive group, lipoic acid pentaerythritol ethoxylate, which is capable of photopolymerization and is suitable for light-based additive manufacturing with high spatial resolution across various length scales. This monomer polymerizes in either the presence or absence of exogenous photoinitiator. Using dynamic light processing and two photon lithography techniques, parts were printed on size scales ranging from multiple cm to μm, with resolution as small as 1 μm. As a result of the dithiolane polymerization, linear disulfides are formed, forming covalent adaptable networks directly from the polymerization reaction. Furthermore, through heating and dilution in solvent, the network was recycled back to the lipoic acid functional monomer with approximately 95% monomer recovery, which was subsequently repolymerized to achieve nearly identical modulus evolution as a function of exposure time. This work represents an advance in the development of multifunctional dithiolane monomers, as well as recyclable resins for additive manufacturing that are capable of polymerization with or without exogenous photoinitiators.

  PublisherOA PDFDOI

• Reducing Haze of Holographic Gratings Recorded in a Two-Stage Photopolymer

  Macromolecules · 2025-01-13 · 7 citations

  articleSenior authorCorresponding

  The haze developed during the recording of holographic gratings was investigated and mitigated in a typical two-stage holographic photopolymer system where a high-refractive-index acrylate (1,3-bis(phenylthio)-2-propyl acrylate, i.e., BPTPA) was utilized as a writing monomer. An acrylate writing monomer (1,3-bis(phenylthio)-2-propyl urethane ethyl acrylate, i.e., BPTPUA) was proposed and synthesized to achieve a lower interaction parameter (χ) between the matrix and the writing monomer. Confirmed by theoretical predictions and experimental photolithography results, the formulation incorporating BPTPUA exhibited a significant improvement in miscibility between the two phases as compared to the analogue compound without a urethane, BPTPA. The higher miscibility led to dramatically lower haze of holographic gratings, due to which the quality of angular playback curves from holographic gratings improved from being strongly distorted to being well-matched with the Kogelnik coupled wave theory. Additionally, a higher light intensity reduced the haze remarkably due to the potential kinetic restriction for phase separation and lower molecular weight of the photopolymer formed. The molecular weight decrease at higher light intensity was confirmed experimentally, and the trend was fit by a theoretical calculation of the kinetic chain length. Using the fitted relationship, the free energy change of mixing was calculated and suggested that a higher light intensity improved the miscibility between the photopolymer and the matrix thermodynamically. Moreover, a reactive matrix was introduced to mitigate the haze development by forming covalent bonds between the two phases. With contributions from covalent attachment and BPTPUA as the writing monomer, haze as low as 0.5% was achieved in a 50 μm recording medium at an extremely high light intensity (200 mW/cm2) for holographic grating.

  PublisherDOI

• Preparation of Degradable Polymers Containing Tunable Ratios of Dithioacetals and Disulfides via Mixed Mode Polymerization

  Angewandte Chemie · 2025-08-21 · 1 citations

  articleSenior authorCorresponding

  Abstract Degradable polymers hold promise for their recyclability and their potential to facilitate the transition toward a circular economy of plastics. As such, a consecutive di‐SN2 reaction between dithiols and polyhalogenated compounds was used to produce degradable polymers with tunable amounts of redox‐enabled dithioacetal and disulfide linkages. The reaction employed bases of varying strengths and different thiol types, allowing for control over molecular weights ranging from &lt;1 kDa to 16 kDa, with tunable degrees of polymerization ranging from 3 to over 75. The ratio of dithioacetals to disulfides was adjusted by manipulating the concentration of the methylene source, enabling the formation of polymers with up to 100% disulfide linkages or up to 93% dithioacetal linkages. This tunability resulted in polymers with multiple redox degradation pathways, capable of being degraded by either reduction or oxidation. Vinyl ether functionalized, telechelic oligomers were used as crosslinkers in network formation, yielding materials with multiple degradation pathways. This di‐SN2 approach provides a promising and straightforward method for creating materials with tailored degradation characteristics.

  PublisherDOI

• Mechanophore Integration in Crosslinked Step‐ and Chain‐Polymerized Polymers and the Resulting Material Properties

  Journal of Polymer Science · 2025-07-21

  articleOpen accessSenior authorCorresponding

  ABSTRACT A facile synthesis, preparation, and integration of a diacrylate‐functionalized mechanophore is presented to demonstrate that a single, identical mechanophore is readily incorporated into polymer networks of various origins as a tool for identifying differences and similarities in the mechanical behavior of these networks. This work investigates polymer mechanical properties during and following stimulation of mechanofluorophore‐incorporated step and chain growth crosslinked polymers. This is achieved with an acrylate‐functionalized benzoxazole mechanofluorophore polymerized via a nucleophile‐mediated thiol‐Michael polymerization (step growth) or a photoinitiated radical acrylate homopolymerization (chain growth). These systems were tuned to have similar storage moduli by incorporating a monofunctional acrylate as a chain extender and crosslink density diluent in the chain growth network. Uniaxial tensile tests indicate that mechanophore incorporation in both systems results in an increase in the percent strain at break compared to control materials without the benzoxazole mechanophore but otherwise maintained monomer composition. Integration of the mechanofluorophore was also implemented in dynamic networks formed from step and chain growth polymerizations where the presence of disulfide bonds facilitated thermally activated bond rearrangement for stress relaxation. The presence of the mechanofluorophore in these networks did not inhibit the dynamic nature of the networks as evidenced by comparable stress‐relaxation traces.

  PublisherOA PDFDOI

• Abstract 1798 Histone H3 N-terminal recognition by the PHD finger of PHRF1 is required for proper DNA damage response

  Journal of Biological Chemistry · 2025-05-01

  articleOpen access

  Plant homeodomain (PHD) fingers are critical effectors of histone post-translational modifications (PTMs), acting as regulators of gene expression and genome integrity, and frequently presenting in human disease. While most PHD fingers recognize unmodified and methylated states of histone H3 lysine 4 (H3K4), the specific functions of many of the over 100 PHD finger-containing proteins in humans remain poorly understood, despite their significant implications in disease processes. In this study, we undertook a comprehensive analysis of one such poorly characterized PHD finger-containing protein, PHRF1.

  PublisherOA PDFDOI

• Dithiolane-Ene Copolymerization: Enabling Tunable, Dynamic, Dual-Cure Networks via Real-Time UV–Vis/FTIR Kinetics and Compositional Analysis

  Macromolecules · 2025-07-17 · 6 citations

  articleSenior authorCorresponding

  The radically mediated dithiolane-ene copolymerization enables efficient incorporation of dynamic disulfide bonds into vinyl polymers, facilitating control over dynamic disulfide bond integration. However, the reactivity of various vinyl monomers and the nature of their copolymerization with the dithiolane remains largely uninvestigated. This study employs a simultaneous FTIR/ultraviolet–visible (FTIR/UV–vis) apparatus in combination with other techniques such as NMR to examine the real-time kinetics, composition, and structure of copolymers formed with 1,2-dithiolanes and various vinyl monomers, including acrylates, methacrylates, vinyl ethers, vinyl sulfides, norbornenes, and allyl ethers. All vinyl monomers, except allyl ether, readily copolymerized with the methyl ester of lipoic acid (LipOMe), showing significant conversion within seconds to minutes of irradiation. Acrylates and vinyl ethers reacted most rapidly, each achieving greater than 82% conversion within 30 s while methacrylates reacted more slowly. Vinyl sulfides reached a final conversion of 48%, surpassing previous reactivity with linear disulfides and showing promise for dithiolane-yne copolymerizations. Additionally, acrylates and vinyl ethers exhibited complementary behavior, integrating with dithiolanes in 2:1 and 1:2 vinyl: dithiolane functional group ratios, respectively, while norbornene displayed a secondary mechanistic pathway that is hypothesized to result from disulfide bond exchange, yielding nearly 1:1 stoichiometric dithiolane:ene integration. Thermal reversion studies confirmed random incorporation of reducible disulfide bonds in acrylates. Utilizing this complementary behavior in acrylates and vinyl ethers, networks were formed and subjected to stress relaxation studies, which revealed divinyl ether networks relaxed 90% of stress in 3 min, compared to 50% for diacrylate networks in 10 min, demonstrating the ability to tune the amount of dynamic bonds and dynamic behavior based on the vinyl/monomer choice. Finally, a sequential, dual-cure organogel (10 wt % in DMSO) system utilizing both anionic and radical initiation mechanisms with norbornene achieved a modulus of 104 Pa upon anionic cure and subsequent 10-fold modulus increase following radical generation, demonstrating the potential to design materials with tunable material properties.

  PublisherDOI

Recent grants

• NIH Grant R21CA174479

  NIH · $373k · 2014

• Photoinitiated Reactions in Covalent Adaptable Networks

  NSF · $300k · 2013–2018

• NIH Grant R01DE018233

  NIH · $1.4M · 2013

• Photoresponsive Bond Exchange in Liquid Crystalline Polymer Networks: A Route to Complex and Controllable Shape Shifting Materials

  NSF · $372k · 2018–2022

• NIH Grant R21EB012188

  NIH · $413k · 2014

Frequent coauthors

• Jeffrey W. Stansbury

  University of Colorado Anschutz Medical Campus

  238 shared

• Kristi S. Anseth

  University of Colorado Boulder

  235 shared

• Maciej Podgórski

  University of Colorado Boulder

  114 shared

• Neil B. Cramer

  96 shared

• Sirish K. Reddy

  Micro Focus (United States)

  81 shared

• Kathryn A. Berchtold

  Los Alamos National Laboratory

  77 shared

• Chen Wang

  60 shared

• Jeannine E. Elliott

  52 shared

Education

• B.S.

  Purdue University

  1988

• Ph.D.

  Purdue University

  1991

Awards & honors

• Fellow, National Academy of Medicine, 2018
• ACS Roy W. Tess Award in Coatings, 2018
• Mark Scholar Award, American Chemical Society, Division of P…
• Fellow, National Academy of Inventors, 2017
• Plenary Lecture, American Chemical Society National Meeting,…