Light Weavers: How the PST Award Celebrates Polymers Shaped by Light

In the silent, precise world of photopolymer science, light is both the brush and the chisel, crafting everything from smartphone components to sustainable materials out of liquid resin.

The Photopolymer Science and Technology Award

The Photopolymer Science and Technology (PST) Award is a prestigious international award established to honor scientists and engineers who have made distinguished contributions to photopolymer science and technology6 . Managed by the Society of Photopolymer Science and Technology (SPST), it celebrates work that drives progress in this dynamic field, from foundational research to industrial applications that touch our daily lives6 .

More Than Just an Honor

The PST Award is not merely a recognition of past achievement; it is a beacon guiding the future of the field. To be considered, work must meet strict criteria, with one being essential: it must be excellent original work that greatly contributes to the progress and improvement of photopolymer science and technology6 .

Award Criteria

Award committees also look for creative work that suggests future evolutions, or enlightening review papers that educate other scientists and engineers6 . In principle, the commended work must have been published in the Journal of Photopolymer Science and Technology6 .

What Are Photopolymers?

At its core, a photopolymer is a material that changes its physical or chemical properties when exposed to light7 . Think of a liquid resin that, when struck by a specific wavelength of light (often ultraviolet), transforms into a solid plastic object. This process, called photopolymerization, is a molecular-scale event where light triggers a chemical reaction, causing small molecules to link together into a solid, cross-linked network2 7 .

This unique capability makes photopolymers indispensable in modern technology. They are the engine behind several revolutionary manufacturing techniques.

3D Printing

Vat Photopolymerization 3D Printing allows for the layer-by-layer creation of intricate 3D objects from a vat of liquid resin8 .

Electronics

In the semiconductor industry, photopolymers are used as photoresists to transfer circuit patterns onto silicon wafers4 7 .

Coatings & Adhesives

Photopolymers offer fast, efficient, and durable solutions for protective coatings and instant-cure adhesives7 .

Notable Recipients of the PST Award

Year Awardee Affiliation Notable Contribution
2025 Jos Benschop ASML For "bringing EUV Lithography from the research phase to high-volume manufacturing."1 4
2019 Robert D. Allen IBM Research, Almaden Pioneering work in photopolymer materials for microelectronics4
2015 Christopher K. Ober Cornell University Significant contributions to polymer and materials chemistry, including photoresists4
2003 C. Grant Willson University of Texas at Austin Seminal work in the development of innovative photopolymer materials for lithography4

Award Timeline

2003

C. Grant Willson - University of Texas at Austin

Seminal work in innovative photopolymer materials for lithography

2015

Christopher K. Ober - Cornell University

Contributions to polymer and materials chemistry

2019

Robert D. Allen - IBM Research, Almaden

Pioneering work in photopolymer materials for microelectronics

2025

Jos Benschop - ASML

Bringing EUV Lithography to high-volume manufacturing

Breaking New Ground: A Circular Photopolymer Revolution

A prime example of the innovative science the PST Award celebrates is the development of a fully renewable and recyclable photopolymer resin. In a 2024 study published in Nature, researchers tackled one of the biggest environmental drawbacks of conventional 3D printing resins: their status as single-use, petroleum-derived thermosets that end up as waste3 .

The Problem with Traditional Resins

Most photopolymer resins are made from reactive monomers and oligomers derived from petroleum feedstocks3 . Once they are photocured into a crosslinked polymer network, they cannot be melted or easily reshaped. This makes the printed parts difficult to recycle, akin to permanent plastic waste3 .

The Lipoate Solution

The research team found an elegant solution in lipoates, compounds derived from renewably sourced lipoic acid3 . They engineered a resin platform by creating two main components: a multivalent crosslinker (isosorbide lipoate) and a reactive diluent (menthyl lipoate).

Research Reagent Solutions for Circular Photopolymer Experiment

Reagent Function Role in the Circular Process
Isosorbide Lipoate (IsoLp2) Multivalent Crosslinker Forms the primary, dynamic network of the polymer; its disulfide bonds can be broken for depolymerization3 .
Menthyl Lipoate (MenLp1) Reactive Diluent Adjusts the resin's viscosity for printing and participates in the network formation, also capable of depolymerization3 .
Photoinitiator Light-Activation Catalyst Absorbs light to start the polymerization reaction, forming the solid part from the liquid resin3 .
Phosphazene (P1-t-Bu) & Thiophenol Depolymerization Catalysts A catalyst combination used in a green solvent to break the dynamic disulfide bonds and liquefy the printed part for recycling3 .

Inside the Lab: Standardizing the Science of 3D Printing

While creating new materials is vital, so is understanding how to use them predictably. A crucial, yet often overlooked, aspect of photopolymer science is the rigorous measurement of material properties. A major 2025 interlaboratory study tackled this challenge by focusing on a fundamental test in 3D printing: the "working curve."8

The Working Curve: A Blueprint for Printing

The working curve is a fundamental relationship in vat photopolymerization that describes how the thickness of a cured layer of resin (the "cure depth") relates to the amount of light energy it receives (the "radiant exposure")8 . It is most often described by the Jacobs Equation:

Cd = Dp ln(E0/Ec)

Where:

  • Cd is the cure depth.
  • Dp is the depth of penetration, indicating how deep light travels into the resin before it decays.
  • E0 is the radiant exposure of light.
  • Ec is the critical exposure, the minimum energy needed to form a solid8 .

Working Curve Parameters from Standardized Interlaboratory Study8

Light Wavelength Depth of Penetration (Dp) Critical Exposure (Ec)
385 nm 39.2 ± 3.7 µm 12.3 ± 3.0 mJ cm⁻²
405 nm 69.3 ± 3.8 µm 17.9 ± 2.3 mJ cm⁻²

This collective work paves the way for Dp and Ec to be used as reliable material properties listed on technical data sheets, much like the specifications for a battery or a microprocessor. It enables quality control for manufacturers and provides researchers with a common language to compare new photopolymer innovations8 .

The Future, Solidified

From honoring the pioneers who bring us more powerful microchips to enabling a future where 3D printing is both high-resolution and sustainable, the science of photopolymers is fundamentally about transformation. The PST Award shines a light on this progress, celebrating the brilliant minds who use light to reshape our material world. As research continues to push the boundaries—making photopolymers more recyclable, higher-performing, and easier to use—this award will continue to be a testament to the power of innovation, one illuminated layer at a time.

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