DON26TZ01-NV002 TITLE: Modeling for Frontal Polymerization Curing Process
COMPONENT TECHNOLOGY PRIORITY AREA(S): Advanced Materials
PROJECTED CMMC LEVEL REQUIREMENT: Level 2 (Self)
OBJECTIVE: Develop a multiphysics model or toolset to predict frontal polymerization phenomena and to optimize the resin additives (e,g., catalyst, inhibitor, etc.) for an optimized cure with less distortion or residual stress, while ensuring that the front does not self-extinguish.
DESCRIPTION: Frontal polymerization is the process of curing a resin monomer into a polymer with a localized self-sustaining and moving reaction zone. Frontal polymerization has many benefits over traditional resin cure methods, such as reduced cure time from many hours to seconds or minutes [Refs 1,-2], a significant reduction of the energy required to cure (in some cases over 99.5%) [Ref 3], and reduced cost associated with curing a resin [Ref 3].
Frontal polymerization has many potential applications such as increasing cure percentage for thermoset additive manufacturing processes without requiring a post cure, rapid manufacturing of composite structures, and rapid composite curing for accelerated repairs of composite structures.
Frontal polymerization is a very boundary condition dependent process. Changes in boundary conditions, initial conditions (including temperature and initiation methods), resin formulations, resin or composite thickness, as well as the addition of reinforced fibers or materials can drastically affect characteristics like front velocity, front temperature, and whether a front is sustained or terminated. This can make it challenging to predict and synthesize resin systems that can sustain a frontally polymerized cure with different initiation methods, environmental conditions, composite/resin thicknesses, and reinforcement materials.
Currently, phenomenological multiphysics modeling efforts for frontal polymerization are limited to 1D, 2D, or small 3D models, since they are very computationally demanding due to the highly nonlinear coupling of the governing equations and short timescales required for accurate solution convergence. Furthermore, many models do not predict the mechanical response resulting from the frontal polymerization process (i.e., warpage or residual stress of the polymer caused by the frontal polymerization process). Surrogate modeling can drastically reduce the time to simulate a front but often requires training to create the surrogate model in the form of many finite element analyses or experiments that can be very time consuming. Recently a mechanism-based approach has been created, allowing for prediction of frontal polymerization phenomena without requiring differential scanning calorimetry (DSC) testing to obtain properties for different resin formulations [Ref 4].
This STTR topic calls for development of a model or toolset to predict characteristics of the frontal polymerization process such as front temperature, front velocity, and cure percentage, as well as the resulting effects from the frontal polymerization process such as warpage, residual stress, or post cure mechanical strength. The model should work for multiple initiation methods (i.e., a point initiation of the front, line initiation, and planar initiation for the front (for simulating a point heat source, a line/wire heat source, and a planar heat source). The model should also be scalable, allowing for simulation of different/larger geometries without detrimental increases in computational time. This topic falls under the NAWCAD STTR focus area for in situ material detection and repair solutions.
PHASE I: Develop the framework for a model and determine if the model can predict a frontal cure of a resin with at least one experimentally cured front of a resin as the starting foundation for validation of the model. The model should predict characteristics such as cure percentage, thermal gradients, and front velocity.
The Phase I effort will include prototype plans to be developed under Phase II.
PHASE II: Use a model or framework to optimize additive concentrations (e,g,, catalyst wt%, inhibitor wt%, etc.) to reduce distortion, front temperature, or residual stress for a frontally cured polymer, while ensuring that the front is sustained leading to a fully cured polymer. Use a model or have a framework for simulating or predicting the curing of a fiber reinforced resin. Optimize the additive concentration percentages to reduce distortion of a frontally cured composite patch or panel, while maximizing the percent fiber volume fraction, and ensuring a sustained front/cure. Experimentally validate the model via frontally cured resin and frontally cured composite samples. Optimize the frontal polymerization process for a successful composite cure for different boundary or initial conditions (i.e. ambient temperatures, thicknesses of composite, initiation methods, etc.).
PHASE III DUAL USE APPLICATIONS: Fully develop the model and transition the model and frontal polymerization technology targeting repair applications for NAVAIR. Create representative panels and/or repair patches that meet specifications required for Navy adoption of the technology.
This technology could benefit the private sector by reducing time and cost associated with curing composite structures or performing composite repairs. This could lead to a reduced cost for cured composite structures. Potential secondary applications include reduced cost automotive composite manufacturing, marine/boat composite manufacturing, and renewable energy composite manufacturing.
REFERENCES:
KEYWORDS: Frontal Polymerization; Finite Element Analysis; Composites; Rapid Manufacturing; Rapid Repair; Multiphysics Modeling; Polymerization
| 5/5/26 | Q. | how many awards are anticipated under this topic? |
| A. | In general, the DON will select 3 proposals for Phase I award. | |
| 05/04/2026 | Q. | FAQ provided by Technical Point of Contact: Besides initiation methods, what types of boundary conditions are you interested in capturing with this tool, and over what range of inputs? (e.g., ambient temperature BC from 35F to 125F) |
| A. | Boundary conditions should be determined by the firm, however, simulating a range of boundary/initial temperatures relevant to "most" environments could be beneficial (i.e. ~35F-120F). However, this is not a requirement for the phase I scope of the topic. | |
| 04/29/2026 | Q. | FAQ provided by Technical Point of Contact: The referenced literature covers both epoxy and DCPD resin systems. Is there a preferred chemistry, or an existing experimental dataset you would expect Phase I proposals to validate against? |
| A. | Any formulation that is frontally polymerizable is acceptable for the topic. However, a frontally polymerizable resin system that exhibits a "long" shelf life (i.e. months or longer) after formulation without undergoing bulk polymerization could be viewed as advantageous. | |
| 4/26/2026 | Q. | Extension to new resin systems or chemistries. Are you only interested in mechanism-based models? How important is robustness across different resins and polymerization mechanisms? How is this weighed against "scalable"? The mechanism-based model uses reaction kinetics knowledge established over 30 years for specific ROMP systems (work by Grubbs, Chauvin, Schrock, and others). For new resin systems or different polymerization mechanisms, many of the required mechanistic steps and kinetic parameters would not be available and determining them is more complex and time-consuming than DSC-based characterization, which can be automated and parallelized. DSC measurements also remain important for the reaction modeling approach; for example, a key parameter in the Bistri et al. paper, activation energy, is taken from Kessler and White (2004), where it was determined using serial DSC experiments. For example, frontal polymerization of radical cationic polymerization of epoxies, follow fundamentally different pathways. Even within ROMP, alternative catalyst inhibition mechanisms used in FROMP (e.g., enol ether-based systems) can alter reaction order in ways that require significant rework of the mechanism model. |
| A. | We are open to any models that can model/simulate frontal polymerization phenomena (not just mechanism-based models). Robustness across different/multiple resins and frontally polymerizaable mechanisms is not in any way required for this topic, but it could be viewed as advantageous. Scalability of the model to allow for accurate simulation of "large" geometries/domains (i.e. being able to accurately simulate patches/small panels) would be more desired for this topic. | |
| 4/26/2026 | Q. | Model scalability and prioritization criteria. You indicate interest in a model that is "scalable."
1. Do you strictly mean working on larger length scales (millimeter vs. meter)? How is that weighed against the ability to "scale" by cooperative stacking of other modeling capabilities that predict warpage, residual stress, or mechanical property prediction, even if it works on smaller length scales? 2. What level of computational efficiency improvement (or preservation) would be considered meaningful when addressing larger-scale problems? Do you have quantitative benchmarks that define acceptable tradeoffs between increased problem size (or geometric complexity) and computational cost? There are no systems that can handle more complex problems with 0.000% increase in compute time. |
| A. | 1. I do mean working on larger length scales (i.e. going from mm to inches or a foot roughly speaking). Additionally, a model that simulates the frontal polymerization process in higher spatial dimensions MIGHT be more beneficial IF it can more accurately simulate spatially varied initial temperature conditions (i.e. 3D compared to 2D compared to 1D domains) IF it can still be solved in a "reasonable" amount of time (i.e. solvable within days or less than a couple weeks).
2. I do not have quantitative benchmarks that define acceptable tradeoffs between increased problem size and computational cost. Increase in computational time when scaling to larger geometries (i.e. patches/small panels) is acceptable so long as it is solvable in a "reasonable" amount of time (i.e. solvable within days or less than a couple weeks), so long as it still simulates frontal polymerization phenomena. It is however desirable to minimize the computational time if possible. |
** TOPIC NOTICE ** |
The Navy Topic above is an "unofficial" copy from the Navy Topics in the DoW FY-26 Release 1 SBIR BAA. Please see the official DoW Topic website at www.dodsbirsttr.mil/submissions/solicitation-documents/active-solicitations for any updates. The DoW issued its Navy FY-26 Release 1 SBIR Topics pre-release on April 13, 2026 which opens to receive proposals on May 6, 2026, and closes June 3, 2026 (12:00pm ET). Direct Contact with Topic Authors: During the pre-release period (April 13, through May 5, 2026) proposing firms have an opportunity to directly contact the Technical Point of Contact (TPOC) to ask technical questions about the specific BAA topic. The TPOC contact information is listed in each topic description. Once DoW begins accepting proposals on May 6, 2026 no further direct contact between proposers and topic authors is allowed unless the Topic Author is responding to a question submitted during the Pre-release period. DoD On-line Q&A System: After the pre-release period, until May 20, 2026, at 12:00 PM ET, proposers may submit written questions through the DoW On-line Topic Q&A at https://www.dodsbirsttr.mil/submissions/login/ by logging in and following instructions. In the Topic Q&A system, the questioner and respondent remain anonymous but all questions and answers are posted for general viewing. DoW Topics Search Tool: Visit the DoW Topic Search Tool at www.dodsbirsttr.mil/topics-app/ to find topics by keyword across all DoW Components participating in this BAA.
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