Performance Evaluation of Next-Generation Bentonite Extender for Drilling Applications

This presentation explores NEX 1502, a high-performance bentonite extender engineered to enhance the yield and rheological properties of low-solid drilling fluids. Developed using poly(2-propenamide) technology, NEX 1502 improves viscosity, swelling capacity, and slurry stability even at low dosages.
With proven improvements in Free Swelling Value (FSV), Packed Wet Aggregate (PWA), and Wet Tensile Strength (WTS), the additive delivers superior performance and sustainability, qualifying under Green Seal standards.
The journal highlights the mechanism of polymer–clay interaction, comparative performance data, market trends, and future scope of polymeric extenders in the drilling and clay processing industries.
GCHEMICS PRIVATE LIMITED continues to pioneer eco-friendly and high-efficiency chemical solutions for mining, drilling, and industrial applications.

1. Polymer-Based Bentonite Extender : Advancing the Performance
of Low-Solid Drilling Fluids
Trinay Majumder
Journal no: GCHEM/NEX/2025/041
October 2025
Abstract
The growing shortage of high-quality bentonite deposits and the increased operational expense of
drilling fluids have spurred industries to design superior polymeric additives that improve bentonite
performance without sacrificing environmental safety. NEX 1502, a polymer-based bentonite extender
made by GCHEMICS PRIVATE LIMITED, is an extremely effective additive for low-solid, non-dispersed
drilling fluid systems. Its novel composition—poly(2-propenamide) with ethenyl benzene and 6-
pentahydroxyhexan-2-one—functions as a rheological enhancer and extender, enhancing parameters
like Free Swelling Value (FSV), Packed Wet Aggregate (PWA), viscosity, and Wet Tensile Strength (WTS).
Laboratory research indicates that there is a significant increase in performance compared to untreated
bentonite. It discusses its chemical mechanism, mode of working, performance testing, and possible
market applicability in the developing drilling and clay processing industries.
Key Words
Bentonite Extender; Drilling Fluids; Rheological Enhancement; Polyacrylate Polymer; Low-Solid Mud
Systems; Free Swelling Value; Clay Hydration; GCHEMICS; NEX 1502; Sustainable Additive.
Introduction
Natural clay, primarily montmorillonite, bentonite has been a staple in drilling fluid design for many
years because of its swelling, suspension, and viscosity-building properties. Recent depletion of high-
quality bentonite ore and increasing environmental regulations have made performance-extending
additives essential to reduce solid content while meeting or surpassing API standards of performance.
Today's drilling operations need to have fluids capable of suspending cuttings efficiently, minimizing
fluid loss, and exhibiting rheological stability under different conditions. The establishment of synthetic
or semi-synthetic polymeric extenders offers an optimal solution to this problem.

2. NEX 1502, as formulated by GCHEMICS PRIVATE LIMITED, is a poly(2-propenamide)-type polymer
formulated to enhance the performance of bentonite. It is different from conventional additives as NEX
1502 provides superior dispersion, improved yield, and elevated viscosity at low dosage and is an
environmental-friendly product under Green Seal certification. NEX 1502 is especially useful in low-
solid, freshwater, non-dispersed mud systems where viscosity and yield must be preserved for optimal
drilling efficiency.
Mechanism of Action
The better performance of NEX 1502 is attributed to its anionic polymeric structure, which dynamically
interacts with clay platelets by both electrostatic and steric means.
1. Electrostatic Stabilization
Bentonite particles inherently have negatively charged surfaces and positively charged edges. NEX
1502's anionic polyacrylate chains adsorb on the edges, neutralizing localized positive sites and bringing
in uniform negative charge distribution. It causes repulsive inter-particle forces to avoid aggregation,
resulting in improved dispersion and hydration of bentonite particles.
2. Polymer Bridging and Network Formation
The extended poly(2-propenamide) molecular chains serve as bridges between discrete clay platelets.
This creates a soft, three-dimensional polymer–clay network that enhances the apparent viscosity and
gel strength of the slurry, allowing greater carrying capacity in low-solid drilling systems.
3. Hydration and Swelling Enhancement
The bentonite structure's interlayer spaces are encouraged by the hydrophilic functional groups of the
polymer to allow water entry, thus greatly enhancing the Free Swelling Value (FSV) as well as the
overall yield. Such a hydration action enables even the medium-grade bentonite ores to behave as well
as high-grade clays.
4. Structural Stability and Fluid Rheology
Through particle separation maintenance and interlayer hydration, NEX 1502 preserves suspension
stability, lowering sedimentation and enhancing Packed Wet Aggregate (PWA) density. This produces a
homogenous fluid system with reliable rheological responses under dynamic drilling operations.
Experimental Performance Evaluation:
A comparative laboratory study was performed to evaluate the influence of NEX 1502 on bentonite-
based drilling fluids. The results are presented below:

3. Parameter Without NEX 1502 With NEX 1502 % Improvement
Free Swelling Value (FSV) 28 39 +39
Packed Wet Aggregate
(PWA, %)
60 68 +13
Viscosity @ 600 RPM (cP) 35 58 +66
Green Crushing Strength
(GCS, kg/cm²)
750 810 +8
Wet Tensile Strength
(WTS, g/cc)
38 47 +24
Interpretation:
The increase in FSV and viscosity indicates better dispersion and hydration of bentonite
particles.
The improved PWA demonstrates denser, more stable slurry packing.
Enhanced GCS and WTS signify improved structural integrity and performance of the bentonite
under mechanical stress.
These data confirm that NEX 1502 not only increases the effective yield of bentonite but also stabilizes
slurry systems across variable clay types, providing consistent, superior performance in drilling
operations.
Environmental Sustainability:
NEX 1502 is an environmentally safe, Green Seal-approved additive that provides:
Conservation of natural resources through reduced bentonite usage.
Non-toxic composition, harmless for human handling and disposal.
High biodegradability, with low environmental impact.
These characteristics are in keeping with the latest sustainability demands of mining and drilling
operations looking for greener solutions to conventional chemical additives.
Market Trends and Future Scope
The worldwide drilling fluid additive market will expand steadily with growing energy exploration,
geotechnical projects, and demand for sustainable materials. The industry is shifting from traditional
mud systems to low-solids, high-efficiency mud systems to improve penetration rates while drilling and
lower environmental footprints.

4. NEX 1502 perfectly falls within this shift by providing:
High yield with low dosage.
Excellence in rheological stability across a wide pH and temperature range.
Compatibility with non-dispersed and fresh water systems.
Future Scope
Hybrid Formulation Development: Mixing NEX 1502 with silicate or lignosulfonate polymers to
attain multi-functional performance.
High-Temperature Adaptation: Structural adaptation for deep-sea and geothermal drilling
applications where thermal stability is necessary.
Cross-Industry Applications: Application in foundry sands, civil engineering, and wastewater
treatment, where clay-based systems find utility in improved rheology and strength.
Digital Monitoring: Compatibility with real-time viscosity sensors and rheometers to maximize
dosage and minimize wastage.
Conclusion
Introduction of NEX 1502 represents a revolutionary step in drilling fluid technology. By combining the
science of modern polymer chemistry with the natural clay system, GCHEMICS PRIVATE LIMITED has
created an additive that:
Increases the swelling, viscosity, and yield of bentonite.
Strengthens the sustainable rheological and mechanical stability of low-solid drilling fluids.
Provides sustainability and cost-effectiveness in accordance with contemporary environmental
requirements.
This technology is a progressive methodology in bentonite optimization, assuring effective resource
utilization and predictable field performance. NEX 1502 is a standard in the next-generation bentonite
extenders for drilling, mining, and construction markets.
References
American Petroleum Institute (API) Specification 13A: Specification for Drilling Fluid Materials,
2021.
Oil Companies Materials Association (OCMA) DFCP No. 3, Testing Procedures for Drilling Fluids,
2018.
Luckham, P. F. & Rossi, S. (1999). The colloidal and rheological properties of bentonite
suspensions. Advances in Colloid and Interface Science, 82(1–3), 43–92.
Zhang, R. et al. (2018). Polymer–Clay Nanocomposites in Drilling Fluids: Rheological Behavior
and Thermal Stability. Journal of Petroleum Science and Engineering, 167, 462–471.

5. Saboori, R. & Sabbagh, F. (2020). Polymeric Additives for Drilling Fluids – A Review. Journal of
Applied Polymer Science, 137(9), 48411.
Thomas, J. E. (2004). Fundamentals of Drilling Engineering. Society of Petroleum Engineers.
Zhang, L. & Sun, H. (2022). Advances in Bentonite Modification for Environmental and
Industrial Applications. Applied Clay Science, 228, 106635