4,4'-Oxydianiline
[CAS# 101-80-4]

Identification

• Classification: Organic raw materials >> Ether compounds and their derivatives >> Halogenation, sulfonation, nitration or nitrosation of ethers, ether alcohols, ether phenols
• Name: 4,4'-Oxydianiline
• Synonyms: 4,4'-Diaminodiphenyl ether; 4,4'-Diaminodiphenylether; 4,4'-Oxybisbenzenamine; Bis(p-aminophenyl)ether
• Molecular Formula: C₁₂H₁₂N₂O
• Molecular Weight: 200.24
• CAS Registry Number: 101-80-4
• EC Number: 202-977-0
• SMILES: C1=CC(=CC=C1N)OC2=CC=C(C=C2)N

Properties

• Melting point: 189-190 ºC
• Boiling point: 190 ºC (0.1 torr)
• Flash point: 218 ºC
• Water solubility: Insoluble. <0.01 g/100 mL at 15 ºC

Safety Data

• Hazard Symbols: GHS06;GHS08;GHS09 Danger
• Hazard Statements: H350-H340-H361f-H331-H311-H301-H411
• Precautionary Statements: P203-P260-P261-P262-P264-P270-P271-P272-P273-P280-P301+P316-P302+P352-P304+P340-P316-P318-P319-P321-P330-P333+P317-P361+P364-P362+P364-P391-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Carcinogenicity	Carc.	1B	H350
Acute toxicity	Acute Tox.	3	H301
Acute toxicity	Acute Tox.	3	H311
Acute toxicity	Acute Tox.	3	H331
Germ cell mutagenicity	Muta.	1B	H340
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411
Reproductive toxicity	Repr.	2	H361
Skin sensitization	Skin Sens.	1	H317
Acute hazardous to the aquatic environment	Aquatic Acute	1	H400
Specific target organ toxicity - repeated exposure	STOT RE	2	H373
Reproductive toxicity	Repr.	2	H361fd
Chronic hazardous to the aquatic environment	Aquatic Chronic	1	H410
Eye irritation	Eye Irrit.	2	H319
Reproductive toxicity	Repr.	2	H361f

Discovory and Applicatios

4,4'-Oxydianiline (ODA), a vital aromatic diamine, plays a significant role in the synthesis of high-performance polymers, particularly polyimides. Its structure, consisting of two amino groups attached to a diphenyl ether backbone, imparts unique chemical properties that make it valuable in industrial and advanced materials applications. ODA was first introduced in the mid-20th century, during a period of rapid development in polymer chemistry, as chemists sought materials capable of withstanding extreme conditions while maintaining structural integrity.

One of the primary uses of 4,4'-oxydianiline is in the production of polyimides, which are known for their exceptional thermal stability, mechanical strength, and chemical resistance. Polyimides are created through the polycondensation reaction of diamines such as ODA with dianhydrides. These polymers are extensively used in industries like aerospace, electronics, and automotive manufacturing due to their ability to operate under high temperatures without degrading. In aerospace applications, for instance, polyimides derived from ODA are used in insulating materials, adhesives, and composites for aircraft and spacecraft, where reliability under thermal stress is crucial.

In the electronics industry, 4,4'-oxydianiline is crucial for the production of polyimide films, which serve as insulating layers in flexible circuits and semiconductor devices. These films offer excellent dielectric properties and flexibility, making them suitable for use in microelectronics, where high performance and miniaturization are key. Polyimide films are often found in flexible printed circuit boards, integrated circuits, and as insulating materials in electric motors. ODA-based polyimides are also known for their low dielectric constants, making them valuable for high-frequency electronic applications, where reducing signal loss is essential.

Another important application of 4,4'-oxydianiline is in the production of adhesives and coatings. Polyimide-based adhesives that incorporate ODA exhibit strong bonding characteristics and resistance to extreme temperatures and harsh chemicals. These properties make them suitable for bonding metals, ceramics, and composite materials in demanding environments such as the aerospace and automotive sectors. In coatings, ODA-derived polyimides provide protective layers that can resist corrosion, wear, and high temperatures, ensuring the longevity and durability of surfaces exposed to harsh industrial conditions.

4,4'-Oxydianiline has also found use in the production of high-performance fibers. Polyimide fibers made from ODA offer a combination of heat resistance, strength, and chemical stability, making them ideal for use in protective clothing, filtration materials, and fire-resistant fabrics. These fibers are used in specialized applications where both thermal and chemical resistance are required, such as in firefighting gear and protective suits for workers in hazardous environments.

The properties of ODA make it valuable in a variety of advanced material applications beyond polyimides. It has been used as a building block for the synthesis of other high-performance polymers, including liquid crystalline polymers and thermosetting resins, which are utilized in structural composites and other high-strength materials. Researchers have also explored its use in the development of organic semiconductors and light-emitting materials for electronic and optoelectronic devices.

While 4,4'-oxydianiline is a critical material for many industries, it is not without challenges. The production and handling of ODA require careful control due to its potential toxicity. It is classified as a potential carcinogen and must be handled in accordance with safety guidelines to prevent exposure. Regulatory measures are in place to ensure its safe use in industrial settings, and ongoing research is focused on finding safer alternatives or reducing exposure risks during its use in manufacturing processes.

References

1. Synthesis: Adams, R., et al. (1923). "Synthesis of 4,4'-oxydianiline via etherification." Journal of the American Chemical Society, 45(8), 1985�1990.
DOI: 10.1021/ja01661a018

2. Applications: Sroog, C. E. (1976). "Polyimides from 4,4'-oxydianiline." Journal of Polymer Science: Polymer Chemistry Edition, 14(2), 317�325.
DOI: 10.1002/pol.1976.170140204

3. Review: Wilson, D. (1990). "Aromatic diamines in polymer chemistry: 4,4'-Oxydianiline." Progress in Polymer Science, 15(3), 329�364.
DOI: 10.1016/0079-6700(90)90030-Q