Difference between ethylene glycol and pta

In the chemical industry, ethylene glycol (EG) and poly terephthalic acid (PTA) are two important raw materials, which are widely used in the manufacture of polymer materials, textiles, flame retardants and other fields. Because of their significant differences in molecular structure, performance characteristics and application areas, they are treated differently in industrial production. This article will analyze the difference between ethylene glycol and PTA in detail from multiple angles to help chemical workers better understand the characteristics of these two materials and their applications in industry.

1. ethylene glycol and PTA basic information comparison

1. Molecular structure and chemical properties

Ethylene glycol is a simple diol, molecular formula C2H6O2, simple structure, no aromatic odor, low boiling point (boiling point of about 100 ℃), soluble in water and organic solvents. It is a colorless transparent liquid with low density, commonly used in the manufacture of polyester, alcohol ether and other chemical products.

And PTA is a kind of poly terephthalic acid, molecular weight is larger, the molecular structure is complex, aromatic, with a strong aromatic odor. There are many double bonds in the molecule, which makes it have good thermal stability and chemical stability. The molecular structure of PTA makes it maintain its physical and chemical properties under high temperature conditions, which makes it an important raw material in chemical production.

2. Physical properties

The melting point of ethylene glycol is lower, usually around -40 ℃, while the melting point of PTA is higher, usually above 200 ℃. The density of ethylene glycol is small, while PT, the density is more moderate.

3. Breaking strength

The molecular structure of ethylene glycol is relatively simple, the fracture strength is low, and it is easily decomposed by chemical reagents. PTA has a complex molecular structure, strong chemical stability, and can withstand higher temperatures and chemical reactions.

2. ethylene glycol and PTA performance comparison

1. Thermal and chemical stability

Ethylene glycol has low thermal stability and is easy to decompose, especially under high temperature conditions, it is easy to decompose into carbon dioxide and water. This makes its application limited in high temperature industrial environments. PTA has good thermal stability and chemical stability, and can exist stably under high temperature and chemical reaction conditions, so it plays an important role in the manufacture of polymer materials.

2. Corrosion resistance

Ethylene glycol itself has certain anti-corrosion properties, but it is easy to rust in a humid environment. PTA has good corrosion resistance and can be used stably in harsh environments for a long time, so it is widely used in food packaging and pharmaceutical packaging.

3. Flame retardant performance

Ethylene glycol is used as a raw material in some flame retardants, but when it is used as a raw material, its flame retardant properties are limited. PTA is a high-performance flame retardant, which can effectively block the spread of fire, so it occupies an important position in building fireproof materials.

3. Application field comparison

1. Polymer material manufacturing

Ethylene glycol is a typical raw material of polyester materials, which is widely used in the manufacture of plastics, fibers and other materials. PTA is the raw material of polyamide materials, widely used in the manufacture of fiber, flame retardant materials.

2. Textile Materials Manufacturing

Ethylene glycol is an important raw material for the manufacture of polyester fibers, and its products have good flexibility and wear resistance. PTA, on the other hand, is used as a polyterephthalate, and the fibers made from it have better moisture absorption and flame retardant properties.

3. Anticorrosive material manufacturing

Ethylene glycol is used as a solvent for some anti-corrosion materials, but in practical applications, its anti-rust performance is limited. PTA is used as a high-performance anti-corrosion material, which can maintain long-term stability in humid environments.

4. Preparation process comparison

1. Ethylene glycol preparation process

Ethylene glycol is mainly produced by the hydration reaction of ethanol, which is simple in process and low in cost. The preparation process usually adopts catalytic hydration method, which converts ethanol into ethylene glycol under high temperature and high pressure conditions. Ethylene glycol can also be produced by an ethylene oxidation method or the like.

2. PTA preparation process

The preparation process of PTA is more complex, usually using isophthalic acid diester method or toluene dicarboxylic acid method. Both processes require a number of steps, including catalyst selection, control of reaction temperature and time, etc. The preparation of PTA also involves epoxidation and polymerization reactions, and the process requirements are higher.

5. Advantages and disadvantages comparison

1. Ethylene glycol advantages

• Low cost: Ethylene glycol preparation process is simple, low cost, so in industrial applications with high economy.
• Widely used: Ethylene glycol is used as a polyester material, widely used in plastics, fiber manufacturing and other fields.

2. Ethylene glycol shortcomings

• Thermal stability is poor: B two is not very good at high temperature conditions stable existence.
• Easy to decompose: Ethylene glycol is easy to decompose in wet or chemical reaction conditions.

3. PTA advantages

• Thermal stability: PTA can be in high temperature conditions, so in industrial applications with high reliability.
• Anti-corrosion performance is strong: PTA is used as a high-performance anti-corrosion material, which can be used in harsh environments for a long time.

4. PTA's Disadvantages

• Cost is higher: PTA preparation process is complex, so in industrial applications cost is higher.
• Application restrictions: PTA is mainly used to manufacture polyamide materials, and its application range is relatively limited.

6. Future development trend

With the improvement of environmental protection requirements and the increase of material performance requirements, the application prospect of PTA will be broader. In the future, with the progress of synthesis technology, the preparation process of PTA will be more simplified, and its application range will be more expanded. As a cheap chemical raw material, ethylene glycol has a good application prospect in the manufacture of polyester materials.

Conclusion

As two important chemical raw materials, ethylene glycol and PTA have their own unique characteristics in industrial production. Ethylene glycol is an important raw material in the manufacture of polyester materials due to its low production cost and wide application fields, but its poor thermal stability and easy decomposition make its application limited in high temperature industrial environment. PTA, with its good thermal stability and chemical stability, has become the raw material of high-performance materials, which is widely used in textiles, flame retardants and other fields. In the future, with the development of technology, the preparation process of PTA will be further optimized, and its application prospect will be broader. Chemical workers need to understand the differences and characteristics of ethylene glycol and PTA in order to make more scientific and reasonable decisions in industrial production.