I. Theoretical Basis for Reaction Feasibility

1. Structural Characteristics of Amino Silicone Oil 2213
   Amino Silicone Oil 2213 is an amino-modified polydimethylsiloxane, whose molecular chain contains primary amine groups (e.g., aminoethylaminopropyl). The high nucleophilicity of primary amines enables them to attack the epoxy ring of epoxy groups, triggering a ring-opening reaction. For example, model QL-2213 from Qiangli Chemical is clearly labeled as "reactive aminoethylaminopropyl functional polydimethylsiloxane," and its primary amine groups exhibit reactivity with epoxy groups.
2. Reactivity of Epoxy Polyether
   The epoxy groups (-O-) in Epoxy Polyether (e.g., terminal epoxy polyether) are prone to ring opening under acidic or alkaline conditions. For instance, the epoxy groups in terminal epoxy polyether (e.g., GP-600) can undergo nucleophilic addition with amino groups to form a β-hydroxyamine structure.
3. Reaction Mechanism
   The primary amine (-NH₂) in amino silicone oil acts as a nucleophile to attack the epoxy ring of Epoxy Polyether, causing the ring to open and form a C-O-N bond. The reaction usually requires weakly acidic conditions (e.g., catalysis by glacial acetic acid) or high temperatures (85-95°C) to accelerate ring opening. For example, in Patent CN111763325A, amino silicone oil reacts with terminal epoxy polyether in a solvent of glacial acetic acid and isopropanol at 90°C for 3 hours, successfully synthesizing self-emulsifying polyether-modified amino silicone oil.

II. Verification from Experiments and Industrial Applications

1. Support from Academic Research
   Studies by Zhejiang Sci-Tech University show that when the molar ratio of amino groups in amino silicone oil to epoxy groups in Epoxy Polyether is 1:1, the emulsion of the resulting polyether-modified amino silicone oil exhibits optimal stability. Cotton fabrics finished with this emulsion maintain flexibility comparable to that of fabrics treated with original amino silicone oil, while their hydrophilicity is significantly improved (wetting time reduced from >300 seconds to approximately 20 seconds). This confirms the effectiveness of the reaction.
2. Practical Applications in Patent Technologies
   • Crosslinking Modification Process: Patent CN102675652A discloses a method in which amino silicone oil is first crosslinked with epoxy silicone oil, then etherified with monoepoxy polyether to prepare comb-shaped polyether amino silicone oil. This product imparts both flexibility and hydrophilicity to fabrics during textile finishing.
   • Block Polymerization Technology: Patent CN111763325A achieves block polymerization of amino silicone oil and terminal epoxy polyether to synthesize high-molecular-weight polyether-modified amino silicone oil. Its self-emulsifying property eliminates the need for additional emulsifiers in textile finishing.
3. Performance Optimization of Industrial Products
   For example, through the reaction between amino silicone oil and Epoxy Polyether, self-emulsifying silicone oil for textile finishing can be prepared. While retaining the flexibility of the siloxane chain, the introduction of polyether segments endows fabrics with moisture absorption and antistatic properties.

III. Key Control Factors for Reaction Conditions

1. Molar Ratio and Raw Material Selection
   • Molar ratio of amino groups to epoxy groups: The optimal ratio is usually 1:1. Excessive epoxy groups may lead to unreacted residues, affecting product stability; excessive amino groups, on the other hand, may increase the risk of yellowing.
   • Structure of Epoxy Polyether: Terminal epoxy polyether (e.g., GP-600) is more reactive than side-chain epoxy polyether and can form high-molecular-weight block structures to enhance product performance.
2. Reaction Temperature and Catalyst
   • Temperature: The reaction is typically carried out at 85-95°C. High temperatures can accelerate the reaction but require avoiding degradation of silicone oil.
   • Catalyst: Weakly acidic conditions (e.g., glacial acetic acid) can promote epoxy ring opening while inhibiting side reactions (e.g., siloxane hydrolysis).
3. Solvent and Process
   Polar solvents (e.g., isopropanol) can improve the compatibility of reactants, and technologies such as microwave irradiation can shorten the reaction time to less than 3 hours. For example, Patent CN111763325A uses isopropanol as a solvent, and the reaction is completed at 90°C for 3 hours to achieve high conversion.

IV. Product Performance and Application Scenarios

1. Performance Advantages
   • Balance between flexibility and hydrophilicity: The siloxane main chain provides a soft and smooth feel, while polyether segments introduce hydrophilicity, solving the problem of hydrophobicity in fabrics finished with traditional amino silicone oil.
   • Self-emulsifying property: The polyether-modified amino silicone oil produced by the reaction can be directly dispersed in water without additional emulsifiers, simplifying the application process.
2. Application Fields
   • Textile Finishing: Used for soft finishing of fabrics such as cotton and polyester to improve hand feel and impart antistatic properties.
   • Daily Chemical Products: Used as an ingredient in hair conditioners or fabric softeners to improve hair combability and luster.

V. Precautions and Potential Issues

1. Risk of Yellowing
   Residual amino groups in amino silicone oil may oxidize under high temperatures or light, causing fabric yellowing. This can be mitigated by controlling the molar ratio of amino groups to epoxy groups (e.g., 1:1) or adding antioxidants.
2. Control of Side Reactions
   Hydrolysis of the siloxane main chain under strongly acidic conditions should be avoided; therefore, the pH of the reaction system is usually controlled at 6-7.
3. Raw Material Compatibility
   The molecular weight and EO/PO ratio of Epoxy Polyether affect the hydrophilicity and hydrophobicity of the product. Appropriate models should be selected based on specific application requirements (e.g., high EO content enhances hydrophilicity).

Conclusion

（Note: EO = Ethylene Oxide; PO = Propylene Oxide; Patent numbers and product models are retained in their original form to ensure accuracy in technical references.）