Silane coupling agent KH-550

Product Introduction of Silane Coupling Agent KH-550
I. Chemical Properties and Physical Characteristics
Silane coupling agent KH-550, chemically named γ-aminopropyltriethoxysilane (3-Aminopropyltriethoxysilane), has the molecular formula C₉H₂₃NO₃Si and CAS number 919-30-21612. Its molecular structure contains both **amino (-NH₂) and ethoxy (-OCH₂CH₃)** active functional groups, exhibiting the following physical properties:

Appearance: Colorless to pale yellow transparent liquid with a characteristic ammonia odor.
Solubility: Soluble in alcohols, aliphatic hydrocarbons, aromatic hydrocarbons, and other organic solvents; hydrolyzes easily in water to form silanol.
Density and Boiling Point: Density approximately 0.942 g/cm³, boiling point 217°C.
Storage Conditions: Must be sealed and stored in a cool place; stable at room temperature (RT).
II. Core Functions and Mechanism of Action
1. Functional Overview
As a bifunctional coupling agent, KH-550 achieves efficient interfacial bonding between organic polymer materials and inorganic fillers/substrates through both chemical bonding and physical adsorption. Key functions include:

Enhancing mechanical properties of composites: such as flexural strength, compressive strength, and shear strength.
Improving water resistance and electrical performance: particularly significant in wet environments.
Enhancing filler dispersion: reducing agglomeration in polymer systems.
2. Mechanism of Action
Chemical Bonding Theory: The amino group reacts with organic materials (e.g., resins), while the ethoxy group hydrolyzes and forms Si-O-Si covalent bonds with inorganic surfaces (e.g., glass, metal oxides).
Surface Wetting Theory: Reduces interfacial tension, promoting the wetting of inorganic fillers by organic resins.
Dynamic Balance Effect: Forms a flexible interfacial layer during hydrolysis-condensation, alleviating stress concentration.
III. Main Application Areas
1. Composite Reinforcement
Glass fiber/mineral wool treatment: Added to phenolic resins to improve moisture resistance, compression resilience, and interlaminar shear strength.
Resin systems: Suitable for thermosetting/thermoplastic resins such as epoxy, polyester, and polyamide, enhancing the wettability of fillers (e.g., silica, talc).
2. Coatings and Adhesives
Adhesion promoter: Used in polyurethane, epoxy, and acrylic systems to enhance bonding to glass and metal substrates.
Pigment dispersant: Improves uniform distribution of pigments in coatings and reduces flocculation.
3. Casting and Grinding Wheel Manufacturing
Resin sand casting: Reduces the amount of phenolic resin used while improving sand strength and moisture resistance.
Grinding wheel binder: Enhances the water resistance and wear resistance of phenolic resins.
4. Rubber Industry
Filler modification: Treats fillers such as silica and carbon black to improve the physical properties of rubber (e.g., hardness, aging resistance).
IV. Usage Methods and Precautions
1. Recommended Dosage
Direct addition method: Add **1%-5%** by weight of the resin or filler.
Pretreatment method: Prepare a 0.5%-1% ethanol/water solution (pH=4-5) for surface treatment of inorganic fillers.
2. Precautions
Hydrolysis control: Avoid excessive moisture leading to premature condensation; it is recommended to use acetic acid to adjust pH.
Compatibility testing: Verify compatibility with specific resin systems to prevent gelation.
Safety precautions: Avoid direct skin contact; use protective equipment during operation.