SES22251/CAT22251-25 and RTV-4125 are both Shore A25 mold-making silicones, but they support different production priorities. SES22251/CAT22251-25 combines a 90-minute working time with high published tensile strength and elongation, making it attractive when processing latitude and mold flexibility are important. RTV-4125 uses a simpler 1:1 mixing system, lower published component viscosity and a shorter cure cycle for more straightforward routine production.
Addition-Cure Silicone
Platinum-Cure Silicone
SES22251/CAT22251-25 and RTV-4125 are both Shore A25 mold-making silicones, but they are optimized for different production needs. SES22251/CAT22251-25 is better aligned with users who value a longer working window, higher published tensile strength and elongation, while RTV-4125 is better suited to users who prioritize simple 1:1 processing, higher published tear strength and faster mold turnaround.
| Technical Parameter | Shin-Etsu SES22251/CAT22251-25 | MinghuiLink RTV-4125 |
|---|---|---|
| Silicone Type | Addition-cure silicone | Platinum-cure silicone |
| Color | Translucent | Translucent |
| Specific Gravity | 1.06 g/cm³ | 1.06-1.08 g/cm³ |
| Mix Ratio | 100:10 by weight | 1A:1B by weight or volume |
| Shore Hardness | 25 Shore A | 25±1 Shore A |
| Viscosity | 50 Pa·s (~50,000 cP, Base) | 4,700±200 mPa·s* (Part A) |
| Working / Pot Life | 90 min | 35 min |
| Cure Time | 24 hours at 23°C | 5 hours at room temperature |
| Tensile Strength | 7.90 MPa | 4.0±0.5 MPa |
| Tear Strength | 19 N/mm | 26±0.5 N/mm |
| Elongation | 775% | 460±50% |
| Shrinkage | Not publicly listed (described as low shrinkage) | ≤0.1% |
| Temperature Resistance | −40 to +175°C | Up to 250°C / 482°F |
| Technical Data Sources | SES22251/CAT22251-25 | RTV-4125 |
| Technical Parameter | Shin-Etsu SES22251/CAT22251-25 | MinghuiLink RTV-4125 |
|---|---|---|
| Silicone Type | Addition-cure silicone | Platinum-cure silicone |
| Color | Translucent | Translucent |
| Specific Gravity | 1.06 g/cm³ | 1.03-1.05 g/cm³ |
| Mix Ratio | 100:10 by weight | 1A:1B by weight or volume |
| Shore Hardness | 25 Shore A | 25±1 Shore A |
| Viscosity | 50 Pa·s (~50,000 cP, Base) | 4,700±200 mPa·s* (Part A) |
| Working / Pot Life | 90 min | 35 min |
| Cure Time | 24 hours at 23°C | Approximately 5 hours |
| Tensile Strength | 7.90 MPa | 4.0±0.5 MPa |
| Tear Strength | 19 N/mm | 26±0.5 N/mm |
| Elongation | 775% | 460±50% |
| Shrinkage | Low shrinkage; numerical value not publicly listed | ≤0.1% |
| Temperature Resistance | −40 to +175°C | Up to 250°C / 482°F |
| Technical Data Sources | SES22251/CAT22251-25 | RTV-4125 |
| Key Factor | Shin-Etsu SES22251/CAT22251-25 | MinghuiLink RTV-4125 | What It Means |
|---|---|---|---|
| Working Window | 90 min | 35 min | SES22251 provides substantially more time for mixing, deaeration and controlled pouring, especially on larger or more complex molds. |
| Mixing System | 100:10 by weight | 1:1 by weight or volume | RTV-4125 is simpler to measure and batch, particularly for routine manual production. |
| Published Viscosity | 50 Pa·s base | 4,700±200 mPa·s Part A | SES22251 has the higher published viscosity on its stated measurement basis, but the measurement points differ and should not be treated as a strict like-for-like comparison. |
| Cure Cycle | 24 h at 23°C | Approximately 5 h | RTV-4125 is more suited to applications where shorter mold turnaround is important. |
| Tensile / Elongation | 7.90 MPa tensile; 775% elongation | 4.0±0.5 MPa tensile; 460±50% elongation | SES22251 publishes higher tensile strength and elongation, supporting a stronger and more stretchable mold profile. |
| Tear Strength | 19 N/mm | 26±0.5 N/mm | RTV-4125 reports the higher published tear-strength value, which may be relevant for repeated demolding or edge resistance. |
| Temperature Capability | −40 to +175°C | Up to 250°C | RTV-4125 has the higher published upper temperature limit; actual service temperature depends on the application and exposure conditions. |
| Process Positioning | Long-window, high-strength mold making | Simple and faster everyday mold production | The main trade-off is greater processing latitude and published tensile/elongation performance versus simpler mixing and faster turnaround. |
| Application | SES22251/CAT22251-25 | RTV-4125 | Key Consideration |
|---|---|---|---|
| Large Mold Making | Strong candidate | Suitable | The 90-minute working window gives SES22251 more time for extended mold preparation and controlled pouring. |
| Complex / Detailed Molds | Strong candidate | Suitable | Both can reproduce mold detail, while SES22251 offers more processing time for careful mixing, deaeration and placement. |
| Flexible Undercut Molds | Strong candidate | Strong candidate | Both are Shore A25 materials with substantial elongation and can support flexible demolding when mold geometry and release conditions are properly controlled. |
| Routine Mold Production | Suitable | Strong candidate | RTV-4125's 1:1 mixing system and shorter cure cycle make routine batching and production more straightforward. |
| Rapid Prototyping | Suitable | Strong candidate | The shorter published cure cycle of RTV-4125 supports faster mold iteration and prototype turnaround. |
| Resin Casting | Suitable | Suitable | Both can be evaluated for reusable resin molds; resin compatibility, mold durability, production volume and turnaround requirements should guide selection. |
| 3D-Printed Masters | Suitable with compatibility testing | Suitable with compatibility testing | UV-resin residues, coatings and other contaminants can inhibit addition-cure systems. A small compatibility test is recommended before production. |
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Competitor specifications are based on publicly available manufacturer documentation, with links to the original sources where available. Missing values are shown as “Not publicly listed” and are not estimated or inferred. Specifications may change, so always check the latest manufacturer documentation and conduct application-specific testing before production use. Product names and trademarks belong to their respective owners. This comparison is provided for technical and informational purposes only and is not endorsed by the brands mentioned.