N,N'-Bis(1-methylpropyl)-1,4-phenylenediamine
[CAS# 101-96-2]

Identification

• Classification: Organic raw materials >> Amino compound >> Cycloalkylamines, aromatic monoamines, aromatic polyamines and derivatives and salts
• Name: N,N'-Bis(1-methylpropyl)-1,4-phenylenediamine
• Synonyms: N,N'-Di-sec-butyl-p-phenylenediamine
• Molecular Formula: C₁₄H₂₄N₂
• Molecular Weight: 220.36
• CAS Registry Number: 101-96-2
• EC Number: 202-992-2
• SMILES: CCC(C)NC1=CC=C(C=C1)NC(C)CC

Properties

• Solubility: <0.1 g/100 mL (water 20 ºC)
• Density: 1.0±0.1 g/cm³, Calc.^*
• Melting point: 17.8 ºC
• Index of Refraction: 1.555, Calc.^*, 1.539
• Boiling Point: 343.2±25.0 ºC (760 mmHg), Calc.^*
• Flash Point: 192.6±14.9 ºC, Calc.^*

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software.

Safety Data

• Hazard Symbols: GHS05;GHS06;GHS07;GHS09 Danger
• Hazard Statements: H301-H311-H314-H317-H318-H400-H410
• Precautionary Statements: P260-P261-P262-P264-P264+P265-P270-P272-P273-P280-P301+P316-P301+P330+P331-P302+P352-P302+P361+P354-P304+P340-P305+P354+P338-P316-P317-P321-P330-P333+P317-P361+P364-P362+P364-P363-P391-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute hazardous to the aquatic environment	Aquatic Acute	1	H400
Acute toxicity	Acute Tox.	3	H301
Chronic hazardous to the aquatic environment	Aquatic Chronic	1	H410
Serious eye damage	Eye Dam.	1	H318
Skin sensitization	Skin Sens.	1	H317
Skin corrosion	Skin Corr.	1B	H314
Skin corrosion	Skin Corr.	1C	H314
Acute toxicity	Acute Tox.	3	H311
Skin sensitization	Skin Sens.	1A	H317
Specific target organ toxicity - repeated exposure	STOT RE	2	H373
Acute toxicity	Acute Tox.	3	H331
Eye irritation	Eye Irrit.	2	H319
Skin irritation	Skin Irrit.	2	H315
Skin corrosion	Skin Corr.	1A	H314
Acute toxicity	Acute Tox.	4	H302
Acute toxicity	Acute Tox.	4	H312

• Transport Information: UN 2922

Discovory and Applicatios

N,N'-Bis(1-methylpropyl)-1,4-phenylenediamine, commonly referred to as an antioxidant additive, is an aromatic amine derivative with the molecular formula C₁₄H₂₄N₂. The compound is formed by the substitution of two isobutyl groups (-CH₂CH(CH₃)₂) on the nitrogen atoms of 1,4-phenylenediamine, resulting in a symmetrical structure. It has gained prominence in industrial applications, particularly in the rubber and plastic industries, due to its excellent antioxidant properties.

The discovery of N,N'-Bis(1-methylpropyl)-1,4-phenylenediamine is rooted in the mid-20th century when researchers were investigating various aromatic amines for their ability to protect materials from oxidative degradation. During this period, the growing demand for more durable and stable rubber and plastic products led to extensive research into compounds that could act as antioxidants. In this context, N,N'-Bis(1-methylpropyl)-1,4-phenylenediamine was developed as a stabilizer designed to prolong the lifespan of materials exposed to oxidative stress.

As an antioxidant, N,N'-Bis(1-methylpropyl)-1,4-phenylenediamine plays a crucial role in preventing the degradation of rubber and polymeric materials. Oxidative degradation occurs when oxygen reacts with the polymer chains in rubber, leading to the breakdown of molecular bonds and a loss of mechanical properties such as elasticity and strength. This is particularly problematic in automotive tires, industrial rubber products, and plastic components exposed to heat, light, and oxygen over long periods. The inclusion of N,N'-Bis(1-methylpropyl)-1,4-phenylenediamine in rubber formulations helps to inhibit these oxidative reactions by scavenging free radicals and neutralizing peroxides, thereby preserving the material's integrity.

One of the most significant applications of N,N'-Bis(1-methylpropyl)-1,4-phenylenediamine is in the tire industry. Modern tires are subjected to harsh conditions, including exposure to UV radiation, high temperatures, and mechanical wear. The presence of antioxidants such as N,N'-Bis(1-methylpropyl)-1,4-phenylenediamine in the rubber compounds used to manufacture tires significantly enhances their durability and resistance to aging. This results in longer-lasting tires with improved performance, especially in environments where oxidative stress is a concern.

In addition to its use in tires, N,N'-Bis(1-methylpropyl)-1,4-phenylenediamine is also utilized in other rubber-based products, including conveyor belts, hoses, and seals. These products often operate under extreme conditions, making antioxidant protection essential for ensuring their long-term performance and reducing the need for frequent replacements. The ability of this compound to enhance the oxidative stability of such materials has made it an indispensable additive in the manufacturing of industrial rubber products.

In plastics, N,N'-Bis(1-methylpropyl)-1,4-phenylenediamine also serves as an antioxidant, protecting polymeric materials from thermal degradation during processing and extending their useful life in end-use applications. It is particularly effective in preventing the discoloration, brittleness, and mechanical failure that can result from exposure to heat and oxygen.

Despite its many industrial advantages, the use of N,N'-Bis(1-methylpropyl)-1,4-phenylenediamine comes with certain safety and environmental concerns. Like many aromatic amines, it is classified as a hazardous substance, and proper handling protocols are necessary to minimize exposure. It can cause skin and eye irritation upon contact and may pose long-term health risks if inhaled or ingested. Regulatory agencies monitor its usage and recommend strict guidelines for its disposal to prevent environmental contamination. Nevertheless, when used in controlled settings, its benefits as an antioxidant additive far outweigh these risks, particularly in industries where material longevity and performance are critical.

Research into the antioxidant mechanisms of N,N'-Bis(1-methylpropyl)-1,4-phenylenediamine has also provided valuable insights into how aromatic amines function in stabilizing polymers. By scavenging free radicals and interrupting oxidation chain reactions, the compound prevents further damage to the polymer backbone. This understanding has informed the design of new antioxidant systems and has broadened the scope of applications for aromatic amines in materials science.

In summary, N,N'-Bis(1-methylpropyl)-1,4-phenylenediamine represents a significant advancement in the field of material stabilization. Its discovery and subsequent application in the rubber and plastic industries have contributed to the development of more durable, oxidation-resistant products. As an antioxidant, it continues to play an essential role in enhancing the lifespan and performance of materials exposed to oxidative stress, especially in automotive and industrial contexts.