A 2026 study of SBS pressure-sensitive adhesives shows why tackifier loading should be reviewed as a viscoelastic window, not as a single tack number. Buyers should compare the polymer, tackifier, test conditions and end-use evidence before approving a grade for labels, tapes or other adhesive systems.
Direct answer for SBS PSA buyers
Compare the whole viscoelastic window: polymer architecture, tackifier type and loading, test temperature, frequency or dwell time, and the resulting tack, peel, shear or SAFT data. The 2026 SBS study hosted by King Fahd University of Petroleum and Minerals found that phenolic resin can move an SBS PSA through anti-plasticized, balanced and plasticized regimes. A high tack result on its own does not show that the formulation will hold a load or survive the intended temperature.
What the 2026 SBS study adds
The peer-reviewed article, published in Polymer Testing in July 2026, examined phenolic resin as a concentration-dependent modifier in SBS pressure-sensitive adhesives. Its abstract describes three useful formulation regimes. At low resin loading, polymer-resin interactions restricted segmental relaxation and produced an anti-plasticized regime with higher cohesion, slower relaxation and improved thermal shear resistance. At intermediate loading, the study describes a balanced window with energy dissipation without substantial loss of network integrity, together with the most favorable adhesion-cohesion balance and maximum peel performance. At high loading, the system shifted toward plasticization, with lower viscosity, faster relaxation, greater viscous dominance and reduced SAFT.
The study does not provide a universal resin ratio for every SBS grade or end use in the accessible abstract. Treat it as a reason to request a formulation map and controlled comparison, not as a substitute for application testing.
Read rheology as a formulation window
Pressure-sensitive adhesives respond as both elastic and viscous materials during bonding and debonding. Storage modulus, written as G’, describes the elastic part of the response. Loss modulus, written as G”, describes the viscous part. Their ratio is expressed as tan delta. The open-access study in PMC used dynamic mechanical analysis and time-temperature superposition to connect these measurements with end-use tests in a UV-crosslinkable SBS model adhesive.
That study linked low-frequency G’ with slow deformation and shear performance, while high-frequency tan delta helped interpret tack during rapid contact and removal. It also found that UV crosslinking increased cohesion and heat resistance in the tested model, while tack and peel decreased. These are observations from the reported formulations and test conditions. They are useful for deciding what to ask for in a supplier report, but they are not a performance guarantee for a commercial grade.
| Evidence field | Why it matters to a buyer | Minimum question |
|---|---|---|
| Storage modulus G’ | Shows the elastic response used to discuss slow deformation and cohesion. | At what temperature and frequency was it measured? |
| Loss modulus G” and tan delta | Helps describe viscous dissipation and rapid wet-out or debonding behavior. | Does the curve cover the time scale of the process? |
| Tack and peel | Reflect fast contact and separation or a defined peel geometry. | What substrate, dwell time, coat weight and peel speed were used? |
| Shear or SAFT | Tests resistance to sustained load or temperature-driven failure. | What load, area, ramp and failure definition were used? |
SBS and SIS need separate grade discussions
The Kraton polymer adhesives brochure describes a supplier-specific split: SIS polymers are presented for PSA properties and high-speed extrusion coating, while SBS polymers are presented for high cohesive strength, lower cost and solvent coating. The same brochure lists compatibility, melt viscosity, temperature resistance and the balance of tack, peel and shear as formulation considerations.
That distinction is a starting point, not a universal ranking. Jusage SBS grades and SIS grades should be discussed against the actual coating route, substrate, end-use temperature, coat weight and required failure mode. A grade name or polymer family cannot replace a controlled trial with the intended tackifier package.
SBS PSA buyer checklist for a controlled comparison
Where SIS and SBS fit in Jusage applications
For labels and tapes, review the Labels and Tapes application page together with the polymer family and the intended liner or facestock. For packaging, the Packaging application page provides the end-use context. Jusage also provides a Download Center for technical files and a Customized Service page for application discussion.
Share the substrate, process, target temperature, coat weight and test plan through the contact page. Jusage can then discuss whether an SIS or SBS direction is appropriate and which sample or technical file should be reviewed first. The final grade decision remains dependent on the customer’s formulation and validation work.
Frequently asked questions
Does higher tackifier loading always improve an SBS PSA?
No. The 2026 SBS study describes a concentration-dependent shift from anti-plasticization to a balanced window and then plasticization. The direction of tack, cohesion and thermal shear behavior depends on the formulation and test conditions.
Which rheology result should a buyer request first?
Request the temperature and frequency sweep or master curve that covers the process and service time scale, then connect it with tack, peel and shear data measured on the intended substrate. A single room-temperature viscosity value is too narrow for this decision.
Should I choose SIS or SBS for every PSA tape?
No. Polymer family, coating route and required failure mode must be considered together. Supplier technical literature commonly positions SIS for PSA and high-speed extrusion uses and SBS for higher cohesion or solvent-coated systems, but the final choice still requires a grade-specific trial.
Approve the window, not one number
The practical lesson from the 2026 SBS research is simple: approve a grade against a defined formulation and time-temperature window. When a supplier can show the polymer basis, tackifier loading, rheology conditions and end-use tests together, purchasing and formulation teams can see where the material fits and where a new trial is needed.