Material Comparison
Compare verified engineering materials side by side with condition-specific mechanical properties.
| Parameter | Natural Rubber (NR) | Styrene-Butadiene Rubber (SBR) |
|---|---|---|
| Material Family | Rubber & Elastomers | Rubber & Elastomers |
| Subfamily | General-Purpose Diene Rubbers | General-Purpose Diene Rubbers |
| ASTM Designation | NR | SBR |
| ISO Designation | NR | SBR |
| ASTM-D2000 Designation | Type AA | Type AA / BA |
| Element | Natural Rubber (NR) | Styrene-Butadiene Rubber (SBR) |
|---|
| Mechanical Parameter | Natural Rubber (NR)Standard Formulated Vulcanizate (Carbon Black Reinforced) | Styrene-Butadiene Rubber (SBR)Standard Carbon Black Reinforced Vulcanizate (SBR 1500/1712 Series) |
|---|---|---|
| Compression Set (22h at 70°C) · Standard Formulated Vulcanizate (Carbon Black Reinforced) · RANGE · 70 °CUnit: % | 15–35 % | 20–40 % |
Machinability: Cryogenically machined with liquid nitrogen (-196°C) to freeze elastomer below glass transition temperature (Tg ≈ -70°C) for precision lathe turning, grinding, or CNC waterjet cutting with abrasive garnets.
Formability / Cold Working: Masticated on two-roll mills or internal mixers (Banbury) to reduce Mooney viscosity prior to compounding. Readily molded via compression, transfer, or injection molding, and shaped via calendar sheet rolling and multi-cavity extrusion.
Heat Treatment & Annealing: Vulcanized via accelerated sulfur cure systems (typically 140°C to 160°C for 5 to 30 minutes) or semi-EV/EV (efficient vulcanization) formulations to optimize reversion resistance and minimize compression set.
Machinability: Cryogenically frozen below -60°C for grinding, turning, and die cutting; readily trimmed using high-speed rotary steel knives and waterjet cutting.
Formability / Cold Working: Compounded in internal mixers with extensive carbon black or silica dispersion. Processable via multi-pass roll milling, calendar sheet extrusion, and transfer/injection molding.
Heat Treatment & Annealing: Vulcanized with sulfur-accelerator systems (sulfenamides, thiazoles, thiurams) at 150°C to 175°C. SBR crosslinks further during aging (oxidative hardening) rather than softening.