The following are several common coupling agent products currently on the market.
1. Silane coupling agent
2. Titanium ester coupling agent
3. Aluminum ester coupling agent
4. Zirconium ester coupling agent
5. Aluminum titanium composite series
6. Other series (boric acid type, aluminum zirconium composite type, etc.)
1、 Comparison between Silane Coupling Agent and Titanate Coupling Agent:
Silane coupling agents are only effective for fillers containing silicon elements, while titanium coupling agents are suitable for various fillers and have a wide range of applicable resins. Moreover, their function is not limited to improving the strength of composite materials, but also endowing them with a certain degree of flexibility. Please refer to Tables 1, 2, and 3 for details.
Table 1.1 Comparison of Titanate Coupling Agents and Silane Coupling Agents
Titanate silane
① Applicability of resin
② Applicability to inorganic fillers
③ The Importance of Performance
④ Other Thermosetting and thermoplastic resins
Wide applicability
No increase in intensity
Endow flexibility
Mainly plays a role in processing technology performance Only applicable to thermosetting resins
Limited scope of application
Increase intensity
Give rigidity
The advantages and disadvantages are very obvious
Table 1.2 Comparison of Chemical Structures of Titanates and Silanes
Symbol rules titanium酸酯
R1-O-Ti-(O-X1-R2-Y)n silane
(R1-O)2-Si-R2-Y
R-O alkoxy group 1 piece 3 of them
Alkyl chelating function have instable
Eliminate immediate alcohol byproducts as needed can I can't
Form a monolayer can I can't
Hydrolysis energy low Medium to high
Reaction with CaCO3 can I can't
Adverse effects of excess Often there are Occasionally, there are
-(Esterification Reaction - X-linked Polyester) can I can't
Realize X-bonding without relying on unsaturated structures can I can't
X1 Adjacent Group Function have nothing
Generate thermal stability when necessary can I can't
Sulfonyl thixotropy can I can't
Phosphate ester - flame retardancy can I can't
Phosphite ester - anti-aging effect can I can't
Length of R2 groups Long to short short
The effect of reducing viscosity obvious None to moderate
The role of improving the impact resistance of thermoplastic materials very good None to moderate
flash point High to Medium low
Y functional group 3 of them 1 piece
N trifunctionality have Monofunctionality
Hydrolytic stability Good~Excellent Good to poor
Table 1.3 Comparison of Coupling Agents Applied to Fillers
silane coupling agent Titanium ester coupling agent
Having excellent effects Silicon dioxide, glass Most inorganic fillers such as calcium carbonate, barium sulfate, aluminum hydroxide, titanium dioxide, etc
Having a certain effect Talc powder, iron powder, aluminum oxide, aluminum hydroxide Magnesium oxide, calcium oxide, mica, silicon dioxide, glass, etc
Less effective Asbestos, iron oxide, titanium dioxide, zinc oxide Talc powder, carbon black, wood powder
invalid Calcium carbonate, calcium sulfate, barium sulfate, graphite, boron graphite
2、 Comparison of Titanate Coupling Agents, Zirconium Coupling Agents, and Aluminate Coupling Agents
Aluminum has a higher reactivity than titanium and zirconium, and due to its strong reactivity, it generally undergoes reactions during storage, resulting in a shorter storage period.
The heat resistance of zirconium coupling agents is greater than that of titanium and aluminum coupling agents. See Table 1.4 for details
Table 1.4 Comparison of Titanate, Zirconium Ester, and Aluminate Coupling Agents
nature order
Reactive activity
Storage stability
Chemical resistance
Price
varieties (Large) Aluminum>titanium≥ Zirconium (small)
(Good) Titanium=Zirconium> Aluminum l (not good)
(Good) Titanium=Zirconium> Aluminum (not good)
(Low) Aluminum> Titanium> Zirconium (high)
(Multiple) Titanium>Aluminum> Zirconium (less)
Based on the above comparison and the fact that titanium based coupling agents are widely used in both domestic and foreign markets, they have a wide range of sales and high sales volume. Their main characteristics are as follows:
1. Wide range of applications (plastics, rubber, coatings, inks, magnetic materials, pigments, fillers);
2. There are many varieties (Kenrich Corporation in the United States has announced nearly 60 grades, and there are currently dozens of grades in China);
3. Stable storage (such as water-soluble varieties that can be stored for several years);
4. Moderate price (definitely lower than silicon series, slightly higher than aluminum series).
