Industry guide
This is a practical guide to surface science for teams working in the Chemicals industry.
In this guide: the four measurements that matter, where they decide yield in Chemicals, and the standards, use cases and studies behind them.
How chemical R&D and QC teams use four measurements: surface and interfacial tension, contact angle, surface free energy and sliding angle. Each one is tied to a real formulation problem, a standard and a published client study.
Lower interfacial tension alone does not make an emulsion stable. A Harvard study that measured interfacial tension on the Dropometer found stability also needed an elastic film at the interface. Dynamic surface tension matters wherever interfaces form fast, such as foams, sprays and drying films.
Surface measurements catch drift in surfactants, resins and solvent blends before it reaches a customer. One portable kit covers all four measurements, so a single lab can screen and release formulations without booking a shared benchtop instrument.
EN ISO 19403-3 covers the surface tension of coating liquids by the pendant drop method. ASTM D1331 covers surface and interfacial tension of solutions by ring and plate methods. Other parts of ISO 19403 cover contact angle, dynamic contact angle and the tilting plate. Cite the edition your quality system uses.
Measure surface and interfacial tension while you formulate, and contact angle once the product meets a surface. Start with the measurement that matches your failure, then book a 15-minute consult about testing it on your own samples.
In chemical manufacturing, many quality problems start at an interface. A surfactant lot that lowers surface tension less than the last one gives poorer wetting downstream. An emulsion that separates in storage fails the customer, even when its composition passed release.
Self-Healing Elastomer Surface Characterization
Polymer chemists use water contact angle to track surface recovery beside tensile healing efficiency, and to compare how spacer chemistry changes the wettability of new elastomers.
PFAS-Free Reformulation & Repellency
Water and oil contact angles plus surface tension show whether a fluorine free replacement chemistry still repels liquids, before a reformulated product goes to customer trials.
Membrane Surface and Fouling Characterization
Water contact angle shows how hydrophobic a membrane surface is and how fouling or surface modification changes it, a quick check for membrane chemistry and separation teams.
CMC Assessment Techniques for Surfactant Concentration
Surface tension across a dilution series shows the critical micelle concentration, so surfactant producers can confirm lot performance and set how much surfactant a formulation really needs.
Oil and water interfacial tension screens emulsifiers before long storage trials, though a low value alone does not guarantee stability, as published client emulsion work shows.
Foam Control And Foam Quality Tuning
Surface tension of surfactant and antifoam solutions shows how they behave at a new air interface, which helps chemical teams tune foaming in processing and in the product.
Contact Angle and Surface Tension of Corrosive Liquids
Shows how chemical labs measure contact angle and surface tension of acids, electrolytes and ionic liquids, with plastic needles and PTFE slide mounts on the tilting stage.
Drilling and Fracturing Fluid Surfactant Screening
Surface tension and interfacial tension across surfactant dose and salinity help suppliers shortlist flowback aids and mud additives before core tests, within the pendant drop floor near 1 mN/m.
Drift Reduction Adjuvant Strategy for Pesticide Spray
Pendant drop surface tension checks adjuvant dose in each tank mix batch, used beside droplet sizing as a formulation screen rather than a drift test.
Electrolyte Wetting Optimization And Additive Selection
Electrolyte surface tension by pendant drop and contact angle on separators and electrodes help rank additives for faster, fuller wetting before cell formation.
The Dropometer drop shape analysis kit measures contact angle, surface and interfacial tension, surface free energy and sliding angle with one portable setup. Its method was validated against a KRUSS DSA100E in two peer reviewed papers. If you are new to the terms, start with wettability.
A dot means the measurement is the main check for that problem.
| Problem | Contact angle | Surface and interfacial tension | Surface energy | Sliding angle |
|---|---|---|---|---|
| Self-Healing Elastomer Surface Characterization | ||||
| PFAS-Free Reformulation & Repellency | ||||
| Membrane Surface and Fouling Characterization | ||||
| CMC Assessment Techniques for Surfactant Concentration | ||||
| Emulsion Stability Mechanism | ||||
| Foam Control And Foam Quality Tuning | ||||
| Contact Angle and Surface Tension of Corrosive Liquids | ||||
| Drilling and Fracturing Fluid Surfactant Screening | ||||
| Drift Reduction Adjuvant Strategy for Pesticide Spray | ||||
| Electrolyte Wetting Optimization And Additive Selection |
Not sure which test you need? Start with how to choose a wettability testing method.
The angle a liquid drop makes where it meets a solid, in degrees. A low angle means the liquid spreads; a high angle means it beads. Use static angles for quick checks, and advancing and receding angles on real, rough or patchy surfaces, where one static value can mislead.
The force at a liquid surface that pulls it to the smallest area, in mN/m. The Dropometer measures it from the shape of a hanging (pendant) drop, and interfacial tension from a drop of one liquid inside another. Use static values for batch checks and dynamic values when interfaces form fast.
The energy needed to create new solid surface, in mJ/m². It is worked out from contact angles of two or more probe liquids. Use it before bonding, printing or coating to check that a surface is clean and treated enough.
The tilt, in degrees, at which a drop starts to roll or slide off a surface. Use it for water and oil repellent surfaces, where a high contact angle alone does not show that drops will shed.
The droplet images above are taken from the same benchmark series as our open dataset. For each substrate and probe liquid we report:
● Advancing and receding contact angles (and hysteresis)
● Derived surface energy (SFE) values based on multi-liquid measurements
● Measurement conditions, uncertainties, and sample preparation details
Comparing your own droplet shapes and angles against these references is a fast way to spot contamination, treatment drift, or unexpected changes in wettability.
Chemicals teams using the Dropometer.
How a Fortune 500 adhesives R&D team went from a troubled first unit to a redesigned Dropometer
A large adhesives R&D group measures contact angle and surface energy on a redesigned Dropometer, a reference for chemical teams developing adhesives and the substrates they bond.
An emulsion lab measured oil and water interfacial tension by pendant drop, TPM oil at 3 mN/m and octane at about 10 mN/m, feeding its rheology and flow studies.
One shared Dropometer serves several labs, measuring interfacial tension of fluorinated oil emulsions and lipid solutions, and contact angle on silicone elastomers, films and hydrogels.
A plating chemistry company measures contact angle and surface tension in house, with PTFE slide mounts on the tilting stage, a model for labs testing reactive bath chemistry.
A rheology lab paired pendant drop surface tension with rheology of polymer and surfactant mixtures, recording 64.09 to 27.06 mN/m across one surfactant series, 12 readings each.
A small US base oil maker set up contact angle, surface tension, surface energy and sliding angle on one modular bench to study industrial fluids on metal substrates.
Published studies that measured with the Dropometer. Our analysis explains what was measured and how; the original paper is linked beside it.
Bio-based ski wax Prototype Development, Hydrophobicity, Hardness, Biodegradation And Glide Performance On Snow
Researchers measured static contact angle and roll off of fluorine free ski waxes at minus 5 °C with a rented Dropometer, a model for PFAS free wax and coating screening.
Design and implementation of environment chamber for interfacial phenomenon processes
A thesis built a temperature and humidity chamber and used Dropometer surface tension and contact angle of water to check it against known behaviour, for testing under process conditions.
Effect of Polymer Concentration on the Rheology and Surface Activity of Cationic Polymer and Anionic Surfactant Mixtures
Pendant drop surface tension of a cationic cellulose polymer with sodium lauryl sulfate fell from 64.09 to 27.058 mN/m at 250 ppm, showing the complexes were more surface active.
Flow and clogging of capillary droplets
Authors measured octane in water interfacial tension at about 10 mJ/m² on the Dropometer, which set the absolute scale for their models of droplets clogging narrow channels.
Fluorophilic boronic acid copolymer surfactant for stabilization of complex emulsion droplets with fluorinated oil
Interfacial tension of perfluorohexane and water fell from about 30 to about 17 to 20 mN/m with additives, yet only the combined system gave lasting emulsion stability.
Glassy and Jammed Systems: Structures and Dynamics
This thesis used Dropometer oil and water surface tension to normalise yield stress against volume fraction for silicone oil in water emulsions with different droplet sizes.
Influence of Added Surfactants on the Rheology and Surface Activity of Polymer Solutions
Surface tension of four polymers with four surfactant types showed which pairs were more surface active than surfactant alone, and gave a CMC of 350 ppm for one pair.
Influence of Cellulose Nanocrystals and Surfactants on Catastrophic Phase Inversion and Stability of Emulsions
Surface and interfacial tension showed SDS cut oil and water tension from 57.2 to 3.02 mN/m while nanocrystals barely lowered surface tension, helping explain emulsion phase inversion behaviour.
Influence of Surfactants on the Rheological Behavior of Nanocrystal Suspension
Surface tension of cellulose nanocrystal suspensions with HTAB showed a break near 300 ppm that matched rheology changes, tracking surfactant moving onto the particle surfaces.
La reología encuentra distintas transiciones de vidrio y atasco en las emulsiones
Authors measured TPM oil and water surface tension at 3 mN/m on the Dropometer and used it to scale yield stress and deformation energy in their emulsion rheology.
Steady Shear Rheology and Surface Activity of Polymer–Surfactant Mixtures
Surface tension of two polymers with five surfactants, 12 readings each, ranked surfactant effectiveness and estimated aggregation points, with Amphosol the strongest tension reducer.
UV Responsive, Bottlebrush Structured Silicone Elastomers: Synthesis, Healing, and Application
Water contact angle rose from 98.4° to 125° as fluorine spacer content increased, showing how graft chemistry tunes the wettability of new silicone elastomers.
Rheology of Cellulose Nanocrystal and Fumed Silica Suspensions: Influence of Ionic Surfactants
Surface tension located HTAB break points near 229 to 352 ppm in nanocrystal and fumed silica suspensions, helping explain how ionic surfactants change particle network rheology.
Zein Protein Nanoparticles: Fabrication and Rheology of Their Dispersions in Polysaccharides
Surface tension showed zein nanoparticles lower tension in carboxymethyl cellulose and xanthan solutions, levelling off beyond 3 wt%, useful for makers of particle stabilised dispersions.
Standards that describe these measurements for Chemicals. Our page explains how the Dropometer fits each one; the standard itself is sold by its publisher.
ASTM D1331
Covers surface and interfacial tension of paints, solvents and surfactant solutions by ring and plate; the Dropometer reaches both by pendant drop, using the optional cuvette for interfacial tension.
ASTM D1417
Latex makers use its surface tension test to track surfactant at the latex surface; pendant drop gives that value instead of ring or plate, not the other eleven tests.
ASTM D3825
Withdrawn in 2016 but still cited for fast forming interfaces in sprays and foams; pendant drop follows surface tension from about 0.1 s of surface age, not milliseconds.
ASTM D8597
Describes sessile drop contact angle on coatings, substrates and pigments with portable goniometers, so chemical suppliers can check how their products wet a surface outside the central lab.
EN 14210
Sets stirrup or ring measurement of tension between a surfactant solution and an immiscible liquid, 4 to 50 mN/m; the Dropometer uses pendant drop with the optional cuvette.
EN 14370
Describes static surface tension of surfactant solutions against air by plate, stirrup or ring; pendant drop gives the same quantity for producers checking how far each lot lowers tension.
EN ISO 19403-3
Describes surface tension of coating liquids by the pendant drop method, the drop shape analysis the Dropometer runs, so resin and additive makers can test liquids before application.
EN ISO 19403-6
Describes advancing and receding contact angles measured as a sessile drop grows and shrinks, showing how a coating or treated surface holds or sheds liquid.
ISO 1409
Sets ring or plate surface tension for polymer dispersions and rubber latices at 23 °C; pendant drop gives an alternative value for dispersion makers tracking surfactant level between batches.
ISO 19403-2: Paints and Varnishes
Describes working out surface free energy of paints and substrates from contact angles of several liquids; measure on the Dropometer, then run OWRK in the free surface energy calculator.
ISO 19403-7:2024
Describes the tilt angle at which a drop starts to move on a coated specimen, a direct number for repellent and easy clean finishes such as PFAS free replacements.
ISO 4311
Finds the critical micelle concentration from surface tension across a dilution series; a pendant drop series gives the CMC as an alternative to the plate, stirrup or ring it names.
ISO 6889
Measures tension between a surfactant solution and an immiscible liquid with a stirrup or ring; the Dropometer measures interfacial tension by pendant drop with the optional cuvette instead.
Start with the failure you are trying to prevent. Use surface tension for surfactants, inks and coating liquids, and interfacial tension for emulsions. Use contact angle and surface free energy when a coating or adhesive must wet a solid. Use sliding angle for repellent surfaces. Our surface tension y contact angle guides explain each method.
Static surface tension is the value once the interface has settled. Dynamic surface tension tracks how it changes in the first seconds after a new surface forms, while surfactant molecules move to it. Foams, sprays, printing and drying films all depend on the dynamic value. The pendant drop method measures both by imaging the same drop over time. See dynamic surface tension.
Yes. A drop of one liquid is formed inside the second liquid, and the drop shape gives the interfacial tension. You need the density of both liquids at the test temperature. A Harvard team used this pendant drop mode to measure a fluorinated oil and water interface in a published emulsion study.
Measure surface tension across a dilution series, from well below to well above the expected CMC. Plot surface tension against the log of concentration. The CMC is where the falling line meets the flat plateau. Our CMC use case and the ISO 4311 page cover the details.
EN ISO 19403-3 covers coating liquids by the pendant drop method, which is the method the Dropometer uses. ASTM D1331, ISO 1409 y ISO 6889 describe other methods, such as the ring and the plate. The Dropometer does not run those methods, so check which method your specification names before you compare results.
Yes, with care. Choose a needle and syringe that the liquid will not attack, and clean the stage after each test. Our page on contact angle and surface tension of corrosive liquids covers the setup. Tell us the liquid when you book a demo and we will suggest the right parts.
The drop shape method was validated against a KRUSS DSA100E in two peer reviewed papers, one in Review of Scientific Instruments and one in Colloids and Surfaces A. Published contact angle accuracy is 0.35 degrees. Automatic edge and baseline detection gives the same reading from the same image. See our validation papers.
Yes. Chemistry groups have used it for surfactant, polymer and emulsion research, including studies of polymer and surfactant mixtures y glass and jamming transitions in emulsions. Browse every study on our client citations page.
Book a 15 minute consult and we will show the Dropometer measuring the kind of surface or liquid your team works with.
Every page and paper referenced in this guide, grouped by type.
