1. Recommended Core Parameters (Quick Reference)

2. Logic and Impact of Amine Value Selection

1. Relationship Between Amine Value and Adhesion Enhancement
   • Amine value refers to the molar amount of amino groups per unit mass of amino silicone oil, which directly determines the bonding ability with polar sites on the plastic surface.
   • 0.3–0.6 mmol/g: Balances adhesion enhancement and crosslinking stability. The moderate amino group density not only forms effective hydrogen bonds but also does not excessively inhibit the platinum-catalyzed reaction.
   • >0.6 mmol/g: Improves adhesion potential, but excessive amino groups tend to cause delayed crosslinking, reduced hardness, and increased yellowing risk of silicone rubber.
   • <0.3 mmol/g: Weakens the adhesion effect on polar plastics, suitable for scenarios with strict requirements on anti-yellowing or low-polarity plastic bonding.
2. Amine Value Adaptation for Different Plastic Materials
   • High-polarity plastics (PA, PET, PBT, PC): Prioritize 0.5–0.6 mmol/g. Amino groups form strong hydrogen bonds with carbonyl/hydroxyl groups, significantly improving interfacial adhesion.
   • Medium-polarity plastics (ABS, PMMA, PS): Select 0.4–0.5 mmol/g to balance adhesion and crosslinking.
   • Low-polarity plastics (PE, PP): Select 0.3–0.4 mmol/g, combined with surface treatment (corona/plasma) to introduce polar sites, avoiding excessive amino groups affecting crosslinking.

3. Logic and Impact of Viscosity Selection

1. Correlation Between Viscosity and Performance
   • Viscosity is positively correlated with molecular weight, affecting dispersibility, interfacial film-forming properties, and migration in vinyl silicone oil.
   • 500–1500 mPa·s: Good fluidity and dispersibility, suitable for thin coating or rapid wetting scenarios, with minimal impact on the mechanical properties of silicone rubber.
   • 1500–3000 mPa·s: Excellent film-forming properties and stable adhesion effect, with strong universal applicability.
   • 3000–5000 mPa·s: Higher molecular weight ensures long-lasting interfacial adhesion, suitable for thick adhesive layers or high-demand bonding scenarios.
   • >5000 mPa·s: Increases dispersion difficulty and may cause uneven mixing, requiring extended stirring time or preheating treatment.
2. Synergistic Selection of Viscosity and Amine Value
   • High amine value (0.5–0.6) paired with lower viscosity (500–1500 mPa·s) reduces crosslinking inhibition and improves dispersibility.
   • Low amine value (0.3–0.4) paired with higher viscosity (2000–5000 mPa·s) compensates for insufficient amino group density through film-forming properties and enhances interfacial adhesion stability.

4. Key Usage Precautions

1. Addition Level Control
   • The recommended addition amount of amino silicone oil is 1–5% (based on the total mass of silicone rubber). Excessive addition will:
     • Slow down the crosslinking rate of addition-cure silicone rubber (due to coordination between amino groups and platinum catalyst).
     • Reduce the mechanical properties of silicone rubber (tensile strength, tear strength, hardness).
     • Increase migration risk and affect long-term adhesion stability.
2. Mixing Process Points
   • First pre-mix amino silicone oil with vinyl silicone oil (stir for 5–10 minutes at 300–500 rpm), then add the silicone rubber base material.
   • Control the mixing temperature at 25–40℃ to avoid amino group oxidation or abnormal viscosity changes of silicone oil caused by high temperature.
   • Ensure the system is clean, and avoid impurities such as water and alcohols affecting crosslinking and interfacial bonding.
3. Special Treatment for Low-polarity Plastics
   • For non-polar plastics such as PE and PP, it is recommended to first perform corona or plasma treatment to introduce polar groups (e.g., hydroxyl, carbonyl), then apply the mixture system. This can improve the adhesion effect by 30–50%.

5. Recommended Product References

• General-purpose type: Aminoethyl aminopropyl silicone oil with an amine value of 0.45 mmol/g and viscosity of 2000 mPa·s, suitable for most plastics such as ABS, PC, and PMMA.
• High-polarity special type: Aminoethyl aminopropyl silicone oil with an amine value of 0.55 mmol/g and viscosity of 1000 mPa·s, suitable for high-polarity plastics such as PA, PET, and PBT.
• Anti-yellowing type: Aminoethyl aminopropyl silicone oil with an amine value of 0.35 mmol/g and viscosity of 3000 mPa·s, suitable for white/light-colored products and scenarios sensitive to yellowing.

6. Summary and Next-Step Recommendations

Prioritize aminoethyl aminopropyl silicone oil with an amine value of 0.4–0.5 mmol/g and viscosity of 1000–3000 mPa·s, with the addition level controlled at 1–3%. This can significantly improve interfacial adhesion with most plastics while ensuring normal crosslinking of silicone rubber. If you can provide specific plastic materials, silicone rubber type (addition-cure/condensation-cure) and adhesion strength requirements, a more precise parameter and addition level plan can be proposed.