Polymer-modified asphalt formulation is a balance among base-stock cost, polymer loading, high-temperature grade, low-temperature grade, elasticity, and production viscosity. SIP-1111™ PolyExtend gives terminals another control variable: reactive soybean-oil chemistry that can be introduced before or after polymer modification to shift the finished binder’s useful grade range.
In a 2025 laboratory program, a neat binder and three modified formulations were compared by continuous grade, MSCR, softening point, and elastic recovery. All three polymer-modified formulations achieved E-class MSCR performance at 64°C.
Addition sequence changed the grade outcome
The base binder graded 68.3/-24.0. Adding 5% polymer produced a continuous grade of 81.1/-27.7, corresponding to PG 76-22. Introducing 1.5% SIP-1111™ before the same polymer dosage moved the high-temperature grade to 82.2°C. Adding SIP-1111™ after polymer modification extended the low-temperature result to -28.2°C.
| Formulation | Continuous grade | PG grade | Formulation signal |
|---|---|---|---|
| Neat base binder | 68.3/-24.0 | PG 64-22 | Starting blend stock |
| 5% polymer | 81.1/-27.7 | PG 76-22 | Polymer-only reference |
| 1.5% SIP-1111™ then 5% polymer | 82.2/-25.9 | PG 82-22 | Higher high-temperature grade |
| 5% polymer then 1.5% SIP-1111™ | 80.3/-28.2 | PG 76-28 | Wider low-temperature range |
The sequence gives a terminal two practical formulation paths from the same base binder and polymer loading. SIP-first favored the high-temperature grade. Polymer-first preserved the PG 76 high-temperature grade while reaching a PG -28 low-temperature grade.
E-class MSCR performance across the modified binders
At 64°C, each modified formulation reported Jnr 3.2 below the 0.5 kPa-1 threshold associated with E-class traffic. Elastic recovery remained above 73% for all three modified binders.
| Formulation | Jnr 3.2 at 64°C | Elastic recovery |
|---|---|---|
| Neat base binder | 2.146 kPa-1 | 0.57% |
| 5% polymer | 0.138 kPa-1 | 76.35% |
| SIP-1111™ before polymer | 0.129 kPa-1 | 74.88% |
| SIP-1111™ after polymer | 0.172 kPa-1 | 73.28% |
Elastic response persisted through short-term aging
Softening-point and elastic-recovery testing provided a second view of the polymer network. Unaged elastic recovery ranged from 93.8% to 94.5% across the three modified binders. After RTFO aging, the reported range was 88.0% to 89.2%.
| Binder | Unaged softening point | Unaged elastic recovery | RTFO softening point | RTFO elastic recovery |
|---|---|---|---|---|
| 5% polymer | 76.7°C | 93.8% | 74.3°C | 88.0% |
| SIP-1111™ before polymer | 77.2°C | 94.3% | 71.5°C | 89.2% |
| SIP-1111™ after polymer | 74.9°C | 94.5% | 74.7°C | 88.3% |
What this means for a terminal
PolyExtend can help a formulator extract more useful grade range from a difficult or lower-cost base stock while retaining the elastic response expected from a polymer-modified binder. The measured work also gives a foundation for polymer-optimization trials: reduce polymer incrementally, rerun PG and MSCR testing, and select the lowest-cost formulation that meets the required grade and traffic level.
Base-stock chemistry, polymer type, shear history, digestion time, and addition sequence all affect the outcome. SoyLei works with terminal laboratories to establish the formulation window for the actual materials entering production.
Review SIP-1111™ PolyExtend documents · Plan a terminal formulation trial
Source Documents
- SESO Extends PMAC Grade Range – Betunel 2025, SoyLei Innovations, LLC, 2025-03-11 Linked from the PolyExtend article at the operator’s direction.
- SESO Modified Polymer Asphalt Betunel, SoyLei Innovations, LLC, 2025-03-11 Linked from the PolyExtend article at the operator’s direction.
- Betunel Binder Grading Summary, SoyLei Innovations, LLC, 2025-01-14 Linked from the PolyExtend article at the operator’s direction.
- Greca Binder Grading Summary, SoyLei Innovations, LLC, 2025-05-26 Linked from the PolyExtend article at the operator’s direction.
