A new research project at the New Jersey Institute of Technology is taking a closer look at a strange but important behavior in rubber-like materials: their properties can depend on what happened to them before. With a $125,000 New Directions grant from the American Chemical Society Petroleum Research Fund, chemical and materials engineering professor Gennady Gor and his students will investigate how petroleum-derived polymers absorb fluids, swell, contract and change their elasticity over time. The work could improve predictions of how elastomers perform in everything from industrial seals to oil and gas equipment.

Elastomers are polymers capable of undergoing large, reversible deformations. Silicone, neoprene and natural or synthetic rubber are familiar examples. Their molecular chains can stretch, rearrange and return toward their original configuration, giving these materials their characteristic flexibility. Yet exposure to liquids or vapors can dramatically alter that behavior. Hydrocarbon molecules may enter the polymer network, pushing molecular chains apart and causing the material to expand. At the same time, the absorbed fluid can change the polymer’s stiffness, strength and ability to recover its original shape.

Gor’s project focuses on a phenomenon known as hysteresis, in which a material’s current state depends not only on its present conditions but also on the path it took to reach them. For an elastomer, that means the material may respond differently when it is swelling than when it is shrinking, even if its size and surrounding environment are identical. The difference can arise from molecular rearrangements, delayed relaxation or changes in the interactions between polymer chains and absorbed molecules. Such path-dependent behavior is central to understanding why materials sometimes fail to return fully to their previous mechanical state.

The question is especially relevant for petroleum-related technologies. Elastomers are widely used as O-rings, gaskets and seals because they can deform to fill microscopic gaps and maintain a hermetic barrier. In oil and gas environments, however, these components may encounter complex mixtures of hydrocarbons under pressure and at elevated temperatures. If a seal swells excessively, softens or loses its ability to recover after repeated exposure, it can become unreliable. A better understanding of hysteresis could help engineers select materials and operating conditions that reduce leakage and extend component lifetimes.

The new study represents a shift for Gor’s Laboratory for Materials Interfaces. His previous research has largely examined porous adsorbent materials, which collect molecules on their internal surfaces. Elastomers are different: they do not need pores to take up substantial amounts of fluid. Instead, molecules diffuse into the polymer matrix and interact with its flexible chains. The resulting process is more like a sponge absorbing liquid, although the molecular mechanisms are governed by diffusion, thermodynamics and the elasticity of the polymer network.

Günel Nabiyeva, a fourth-year doctoral student, will lead much of the experimental effort with undergraduate chemical engineering student Elitsa Mileva and second-year doctoral student Supun Rangana. The team has already begun collecting data on how rubber deforms in the presence of liquids and vapors. For Mileva, who has spent considerable time reviewing the scientific literature, the grant will provide an opportunity to move deeper into laboratory work. Nabiyeva describes the project as a new system for the research group because the laboratory has not previously studied elastomers in this way.

The researchers will expose polymer samples to controlled concentrations of hydrocarbon vapors and track how the materials respond. Their measurements will combine swelling, fluid uptake and elasticity rather than treating these properties separately. This approach is essential because a polymer can gain mass and volume while simultaneously becoming softer or, under some conditions, displaying a more complicated mechanical response. Different hydrocarbons may produce different results because their molecular size, chemical structure and compatibility with the polymer influence how quickly they enter the material and how strongly they interact with its chains.

Rangana will contribute expertise in ultrasonic sensing, which can measure subtle changes without physically contacting or damaging the sample. Ultrasonic waves travel through a material in ways that depend on its density, structure and mechanical properties. By analyzing changes in wave transmission or reflection, scientists can detect variations in stiffness and internal condition with high precision. Coupling these measurements to vapor exposure could reveal how quickly elasticity changes as molecules enter the polymer and whether the material follows the same path during desorption as it did during absorption.

The team hopes its results will fill a gap in the fundamental understanding of polymer hysteresis. Although hysteresis is well known in many areas of physics and engineering, relatively few studies have examined how history-dependent elasticity develops in swollen elastomers. The new measurements may help distinguish reversible molecular motions from more persistent structural changes and improve models used to predict polymer performance. Ultimately, the researchers aim to make elastomer behavior less mysterious and more reliable, helping engineers design seals and flexible components that remain dependable across repeated cycles of chemical exposure, swelling and recovery.

Subject of Research: Elastomers, petroleum-derived polymers, polymer swelling, elasticity and hysteresis

Article Title: Ultrasonic Experiments Aim to Reveal Why Rubber Remembers Its History

Web References: Gennady Gor’s NJIT profile; NJIT Laboratory for Materials Interfaces

Image Credits: Courtesy of New Jersey Institute of Technology

Keywords

Elastomers, polymers, hysteresis, rubber, polymer swelling, ultrasonic sensors, materials science, chemical engineering, petroleum research, NJIT

Elles sont souvent présentées comme des alliées naturelles capables de purifier l'air de nos intérieurs. Pourtant, derrière cette réputation largement relayée depuis des décennies, les preuves scientifiques racontent une histoire bien différente.

In a groundbreaking study set to reshape our understanding of polar carbon dynamics, researchers have uncovered that the lithology of catchment areas along the Antarctic Peninsula plays a pivotal role in regulating the net carbon balance of these fragile ecosystems. This revelation not only challenges previous assumptions regarding carbon sequestration in polar regions but also highlights the complex interplay between geology and climate change in one of the planet’s most sensitive areas.

For decades, scientists have grappled with accurately quantifying carbon fluxes in polar environments due to the extreme conditions and limited accessibility. The Antarctic Peninsula, stretching northwards from the main Antarctic continent, represents a unique geophysical interface where ice, rock, and ocean converge. Prior research predominantly focused on biological and climatic factors controlling carbon balance but seldom accounted for the geochemical contributions borne from the underlying lithology. This new research sets a transformative precedent by rigorously dissecting how rock types influence carbon absorption and release processes, thereby painting a more nuanced picture of the peninsula’s carbon budget.

The study relied heavily on state-of-the-art field measurements coupled with advanced geochemical modeling to parse out the contributions of catchment lithology—essentially the rock makeup and mineral composition of drainage basins—to net carbon balance. Geological substrates act not only as passive backdrops but as active participants in biogeochemical cycles. Chemical weathering of silicate and carbonate minerals can sequester atmospheric carbon dioxide, while other rock forms may facilitate carbon release via mineral dissolution or hydrological transport mechanisms. The research team meticulously sampled various catchment zones along the peninsula, integrating data from frozen soils, sediment runoff, and meltwater streams to decode these lithological influences.

One of the most striking findings from the investigation was the spatial variability of carbon fluxes directly correlated with geological heterogeneity. Catchments dominated by silicate-rich bedrock exhibited higher carbon sequestration capabilities through rock weathering processes compared to those underlain by carbonate lithologies, which tend to release carbon dioxide during dissolution. This variability suggests that predictions of polar carbon dynamics need to incorporate detailed geological maps and lithological classifications for greater precision. Such insights could significantly improve climate models that currently struggle with polar region parameterization.

Moreover, the researchers illuminated the role of mineral weathering as a long-term sink for atmospheric CO2, contrasting the widely documented biological sinks such as phytoplankton blooms and moss growth. In particular, the slow yet persistent process of silicate mineral weathering draws down carbon dioxide, converting it into bicarbonate ions that are flushed into the ocean. This naturally occurring geological carbon pump could be particularly impactful in the Antarctic Peninsula where rapid glacial retreat exposes fresh silicate rock surfaces, enhancing weathering rates. These observations offer compelling evidence that geological processes may buffer climate change effects, at least regionally, by locking away carbon in mineral forms.

Intriguingly, temporal data spanning multiple melt seasons revealed that net carbon balance is highly sensitive to seasonal variations in temperature and hydrology, which themselves are modulated by lithological factors. For example, catchments composed of permeable volcanic rocks exhibited more pronounced meltwater infiltration, accelerating mineral weathering and carbon sequestration during warm months. Conversely, less permeable sedimentary formations tended to trap water and organic carbon within soils, affecting the timing and magnitude of CO2 fluxes to the atmosphere. This complex feedback between lithology, hydrology, and climate underscores the necessity of interdisciplinary approaches when assessing polar carbon systems.

The implications of these findings reverberate far beyond academic curiosity. As the Antarctic Peninsula experiences some of the fastest warming rates on Earth, understanding the controls on carbon balance is critical for forecasting future climate trajectories. If lithological variability leads to differential carbon sequestration zones, then localized geological disruptions caused by melting glaciers or human activity could substantially alter regional carbon budgets. This knowledge is paramount for policymakers designing effective climate mitigation strategies, particularly in sensitive high-latitude environments where carbon feedbacks may accelerate global warming.

In addition to geochemical and climatological impacts, the study also highlights the potential for emerging technologies such as remote sensing and machine learning to map lithological controls at unprecedented resolution. By integrating satellite imagery with field data, researchers can create predictive models that swiftly identify carbon hotspots and areas vulnerable to carbon loss. This approach holds promise not only for Antarctic research but for global efforts to monitor and manage terrestrial carbon stocks in the face of escalating environmental change.

Furthermore, the interdisciplinary team behind this research underscores the importance of collaboration across geology, ecology, and atmospheric science disciplines. Only through such synergies can the subtle yet powerful effects of geological substrates on biogeochemical cycles be fully appreciated. This holistic perspective marks a paradigm shift in polar science, encouraging future studies to transcend traditional boundaries between earth sciences and climate research.

The work also invites a reevaluation of how catchment-scale processes are incorporated into Earth system models. Historically, these models have neglected fine-scale lithological heterogeneities, instead favoring generalized assumptions about soil and sediment carbon storage. The evidence provided by this study advocates for embedding lithological parameters into model architectures, enabling more accurate simulations of polar carbon dynamics under variable climatic scenarios. Such advancements are vital for anticipating tipping points in Antarctic ecosystems where abrupt changes could trigger widespread carbon release.

As global attention intensifies on polar regions as bellwethers of climate change, the intricate connection between rocks beneath our feet and atmospheric carbon cycles comes sharply into focus. The Antarctic Peninsula serves as a natural laboratory, revealing that the geology beneath evolving ice landscapes is not merely inert background but an active, dynamic component influencing the Earth’s carbon footprint. These insights champion a new era where geosciences play a central role in unraveling planetary carbon mysteries and inform global climate stewardship.

To realize the full potential of these findings, continuous monitoring and expanded field campaigns will be indispensable. The study sets a benchmark for future Antarctic research by demonstrating how integrative methodologies can decode complex environmental phenomena. With accelerating climate pressures threatening polar ecosystems, unraveling the lithological control on carbon balance becomes not just an academic endeavor but an urgent imperative for humanity’s environmental resilience.

In conclusion, this landmark research elegantly reveals how the mineral composition and geological characteristics of Antarctic catchments exert profound control over carbon exchanges between land, atmosphere, and ocean. By amalgamating detailed geochemical analyses with ecological and climatic data, the study enriches our comprehension of polar carbon cycling and offers tangible pathways to improve global climate models. As the Antarctic Peninsula continues to reshape itself under warming skies, understanding the lithological underpinnings of its carbon dynamics will be essential for predicting its role in the Earth’s future climate narrative.

---

Subject of Research: Geology and carbon cycling in the Antarctic Peninsula catchments

Article Title: Catchment lithology controls net carbon balance along the Antarctic Peninsula

Article References:
He, S., Zhang, X., Hu, H. et al. Catchment lithology controls net carbon balance along the Antarctic Peninsula. Nat Commun (2026). https://doi.org/10.1038/s41467-026-74667-9

Image Credits: AI Generated

New research suggests dusty leaves can feed plants in nutrient-poor ecosystems.