Structure, Properties and Innovative Applications of N-Phenyl-3-Aminopropyltrimethoxysilane

Structure, Properties and Innovative Applications of N-Phenyl-3-Aminopropyltrimethoxysilane
The molecular structure of N-phenyl-3-aminopropyltrimethoxysilane has a phenyl ring connected to a secondary amino group, which is then connected to three hydrolyzable alkoxyl groups (in this case methoxy, -OCH3) through a propyl chain (a straight chain consisting of three carbon atoms). The phenyl group is hydrophobic, the amino group and the three methoxy groups are hydrophilic and reactive. This structural feature gives the organosilicon compound a variety of interesting properties and applications.

Reaction Principle:
Phenyl-3-aminopropyltrimethoxysilane is a monoamino silane coupling agent, which has a benzene ring, a secondary amino group and three hydrolyzable alkoxyl groups (methoxy groups) in its molecular structure. This dual reactivity allows them to improve the bonding, adhesion and compatibility between inorganic materials (glass, metals, fillers) and organic polymers (thermosetting resins, plastics, elastomers) through a bidirectional chemical reaction between the two. They can improve the mechanical properties of resin matrix composites or the adhesive strength and water resistance of resin coatings through bi-directional chemical reactions with inorganic materials (glass, metal, fillers) and organic polymers (thermosetting resins, plastics, elastomers).
In different applications, they can be used as coupling agents, adhesion promoters, curing agents, surface modifiers of pigments and fillers.
Due to the partially hydrolyzable nature of trimethoxysilane, phenyl-3-aminopropyltrimethoxysilane can react with water under certain conditions to form silanol groups, which in turn are involved in the synthesis and modification of various silicone-based materials. At the same time, the presence of the phenyl ring and amino group also provides the compound with the possibility of reacting with other organic molecules, such as amidation, sulfonation, nitration and so on.
Since this product is a trimethoxysilane, its hydrolysis is significantly faster than that of triethoxysilane, providing faster reaction and curing, but the by-reaction product of its hydrolysis reaction is methanol, which is slightly less environmentally friendly.
Soluble in alcohol, ether, benzene and other conventional aliphatic and aromatic solvents, with ketone, ester solvent worker carbon tetrachloride reaction; easily soluble in water, but at the same time, hydrolysis reaction will occur.

The hydrolysis reaction of N-phenyl-3-aminopropyltrimethoxysilane occurs automatically in the presence of water without the addition of acids as catalysts. The pH value of their hydrolysate solution is generally 10~11. In order to obtain more stable hydrolysis products, it is recommended to adjust the pH value of the hydrolysate to about 4.
N-phenyl-3-aminopropyltrimethoxysilane will react with ketone and ester solvents, so it is not recommended to use such solvents to dilute this product.
The silane itself or the silanized substrate can react with carbon dioxide in the air to form the corresponding carbonate or carbamate.

As a coupling agent, N-phenyl-3-aminopropyltrimethoxysilane can promote adhesion between inorganic materials and organic polymers and enhance the mechanical properties of composite materials.
As a modifier used in plastics, rubber and other polymer materials, it can improve the weather resistance, abrasion resistance and chemical resistance of the materials.
As cross-linking agent: in the cross-linking process of silicone rubber and other polymer materials, to enhance the physical and chemical properties of the materials.
As a coating additive: used in coatings and adhesives to improve the adhesion and durability of the coating to the substrate.
Suitable inorganic materials for this product include siliceous materials such as glass, glass fiber, glass wool, mineral wool, mica, quartz, etc. and metals and their oxides such as aluminum hydroxide, magnesium hydroxide, kaolin, talc, iron and steel, zinc, aluminum, etc. However, it is basically ineffective on fillers that do not contain hydroxyl groups on the surface, such as calcium carbonate, graphite, carbon black, barium sulphate and so on.