Complex antioxidants: Ideal for a variety of complex formulations, helping to achieve diverse product designs

1. Definition and background of composite antioxidants

In the modern industrial field, the aging problem of materials has always been one of the key factors that restrict product life and performance. Whether it is plastic products, rubber products or polymer materials, they will be affected by various external factors such as oxygen, ultraviolet rays, thermal energy during use, resulting in performance degradation or even failure. This phenomenon is called “oxidative aging”. To solve this problem, scientists have developed a variety of antioxidants and combined different types of antioxidants through compounding technology to form an efficient and versatile solution – composite antioxidants.

1.1 Basic concepts of composite antioxidants

Composite antioxidant is a mixture of two or more antioxidant components designed to enhance antioxidant effects through synergistic effects. It can not only delay the aging process of the material, but also improve the processing performance, mechanical properties and weather resistance of the material. Compared with single antioxidants, composite antioxidants have a wider range of applications and higher cost performance, making them ideal for many complex formulations.

From a chemical point of view, composite antioxidants usually contain the following main ingredients:

Free radical capture agents: such as phenolic compounds (BHT, ascorbic acid, etc.), are used to capture free radicals generated in the material and prevent the occurrence of chain reactions.
Peroxide decomposition agent: For example, thiodipropionate substances can decompose peroxides in the material to prevent them from further induced oxidation reactions.
Metal ion passivator: Such as chelating agents (EDTA, citric acid, etc.), by binding to metal ions, inhibit the oxidation reaction caused by metal catalysis.
Auxiliary antioxidants: Such as phosphites, they can enhance the effect of the main antioxidant while reducing volatility and toxicity.

These components cooperate with each other to jointly build a multi-level protection system, allowing composite antioxidants to show excellent performance in various complex environments.

1.2 Development history and market demand

The history of research and development of composite antioxidants can be traced back to the mid-20th century. With the widespread application of polymer materials, people’s requirements for material stability are also increasing. The initial antioxidants are mostly single components, such as phenol compounds, but due to their single function and limitations, it is difficult to meet diverse needs. In order to break through this bottleneck, researchers have begun to try to combine different types of antioxidants in order to obtain better comprehensive performance.

After entering the 21st century, with the increase in global environmental awareness and the increase in demand for high-performance materials, composite antioxidants ushered in a golden period of rapid development.Especially in the fields of automobile manufacturing, electronic appliances, construction and building materials, the demand for composite antioxidants has shown explosive growth. According to statistics, in 2022 alone, the global compound antioxidant market size has exceeded US$3 billion, and it is expected to maintain an average annual growth rate of 5%-7% in the next few years.

1.3 Application scenarios and importance

The application scenarios of composite antioxidants are extremely wide, covering multiple industries such as plastics, rubbers, coatings, and lubricants. For example, in the manufacturing of automotive parts, composite antioxidants can effectively extend the service life of tires, bumpers and other components; in the field of food packaging, it can ensure that packaging materials will not affect food safety due to oxidation during long-term storage; while in the medical device industry, composite antioxidants help maintain product biocompatibility and stability.

In addition, with the promotion of green chemical concepts, low-toxic, harmless, and environmentally friendly composite antioxidants have gradually become the mainstream of the market. This not only reflects the progress of technology, but also reflects the society’s high attention to sustainable development. It can be said that composite antioxidants have become an indispensable part of modern industry, providing strong support for achieving diversified product design.

2. Mechanism and classification of compound antioxidants

To gain a deeper understanding of the magic of compound antioxidants, we need to start with their mechanism of action. Simply put, composite antioxidants prevent or slow down the oxidation process of the material through a series of complex chemical reactions, thus protecting the material from damage. Next, we will discuss its specific mechanism of action in detail and classify it scientifically according to its function.

2.1 Mechanism of action of composite antioxidants

The oxidation process of a material is usually a chain reaction, including three stages: chain initiation, chain propagation and chain termination. Complex antioxidants exert their protective role by intervening in key steps in these phases.

chain initiation stage: At this stage, some active molecules (such as hydroperoxides) in the material will decompose under the action of external factors (such as light, heat, and oxygen) to form free radicals. The free radical trapping agents in the composite antioxidants quickly bind to these free radicals, converting them into stable compounds, thereby blocking the starting point of the chain reaction.
Channel propagation stage: If the chain initiation cannot be stopped in time, the free radicals will continue to react with other molecules, producing more free radicals, resulting in the chain reaction to continue to spread. At this time, peroxide decomposition agents are on the scene, and they can decompose peroxides into inactive products, thereby interrupting the process of chain propagation.
Channel Termination Phase: Even if the first two stages are controlled, there may still be a small amount of uneliminated free radicals. At this time, the auxiliary antioxidant will be sent.In use, they can completely eliminate residual free radicals by synergistically with other antioxidants, ensuring that the entire oxidation process is completely stopped.

It is worth mentioning that the effect of composite antioxidants is not limited to the antioxidant itself, it can also improve its processing performance and the appearance quality of the final product by adjusting the microstructure of the material. For example, some composite antioxidants can reduce the viscosity of the material at high temperatures and make it easier to form; others can reduce defects on the surface of the material and give the product a smoother touch.

2.2 Classification of composite antioxidants

Depending on the function and mode of action, compound antioxidants can be divided into the following categories:

Category	Typical Ingredients	Main functions
Free Radical Capture	Phenol compounds (BHT, ascorbic acid, etc.)	Catch free radicals and prevent the propagation of chain reactions
Peroxide decomposition agent	Thiodipropionate	Decompose peroxides to prevent them from further induced oxidation reactions
Metal ion passivator	Chalking agents (EDTA, citric acid, etc.)	Binding metal ions, inhibiting oxidation reaction caused by metal catalysis
Auxiliary Antioxidants	Phosophites	Enhance the effect of the main antioxidant while reducing volatile and toxicity

In addition, there are some special functions of composite antioxidants, such as light stabilizers for UV protection and high temperature resistant antioxidants for extreme environments. These products often require a combination of technologies and processes to achieve good performance.

2.3 Current status of domestic and foreign research

Scholars at home and abroad have achieved remarkable results in the study of composite antioxidants. For example, the Irganox series of composite antioxidants developed by DuPont in the United States are well-known for their excellent stability and environmentally friendly properties; Mitsubishi Chemical in Japan has launched green antioxidants based on natural plant extracts, which are widely favored by consumers. In China, the Institute of Chemistry, Chinese Academy of Sciences has also made a series of breakthroughs in the field of composite antioxidants in recent years, especially in the international leading position in the research and development of nano-scale composite antioxidants.

However, despite significant technological advances,Antioxidants still face challenges such as how to further improve their efficiency, reduce costs and develop more new products that meet green environmental requirements. These issues will be the focus of future research.

3. Advantages and application examples of composite antioxidants

If composite antioxidants are a key, then their advantage is to open the secret weapon to the door to high-quality product design. Compared with traditional single antioxidants, composite antioxidants have many unparalleled advantages. Let’s analyze them one by one.

3.1 Core advantages of composite antioxidants

Veriodic: Compound antioxidants can solve various problems at the same time, such as both oxidation and UV protection, which not only improves heat resistance and improves processing performance. This “one-stop” solution greatly simplifies formula design and reduces production costs.
Synergy Effect: The mutual cooperation between different components will produce obvious synergies, making the overall performance far exceed the sum of each part. For example, the combination of free radical capture agent and peroxide decomposition agent can significantly improve the antioxidant efficiency and achieve twice the result with half the effort.
Strong adaptability: Due to the use of multiple ingredients, composite antioxidants can adapt to various complex usage environments and harsh conditions. Whether it is engine parts that work under high temperature and high pressure, or refrigerator seals used in low temperature environments, it can work with ease.
Environmental Friendly: With the increasing strictness of environmental regulations, more and more composite antioxidants are made of renewable raw materials or biodegradable materials, greatly reducing the negative impact on the environment.

3.2 Typical application case analysis

In order to better understand the practical application value of composite antioxidants, we selected several typical industry cases for in-depth analysis.

Case 1: Automobile tire manufacturing

In the production of automobile tires, rubber materials are prone to oxidation and aging due to long-term exposure to air, resulting in problems such as decreasing strength and deteriorating wear resistance. By adding composite antioxidants, not only can this process be effectively delayed, but the flexibility and elasticity of the rubber can also be improved. A well-known tire manufacturer introduced a new composite antioxidant into its high-end product line, and the results showed that the product’s service life was extended by nearly 30%, and customer satisfaction was greatly improved.

Case 2: Food packaging materials

For the food packaging industry, safety is always the primary consideration. Traditional antioxidantAgents may migrate to food, posing potential health risks. Compound antioxidants successfully solved this problem by optimizing the formula and selecting low mobility ingredients. For example, a European company developed a composite antioxidant specifically used in polyethylene films. It has been tested and proved that its migration volume is less than one thousandth of the EU standard limit, winning wide recognition from the market.

Case 3: Medical device coating

In the field of medical devices, compound antioxidants also play an important role. For example, coating a polymer film containing composite antioxidants on the surface of an artificial joint can significantly improve its biocompatibility and corrosion resistance. An American medical device company used this technology to extend the service life of artificial hips from the original 10 years to more than 20 years, bringing good news to patients.

IV. Technical parameters and selection guide for composite antioxidants

For engineers and technicians, it is crucial to understand the specific technical parameters of composite antioxidants. Only by mastering this data can you make an optimal choice in practical applications. The following are several key indicators and their reference values:

Parameter name	Unit	Typical Range	Remarks
Antioxidation efficiency	%	85%-99%	Indicates the ability to capture free radicals
Thermal Stability	°C	200°C-350°C	The ability to maintain activity at high temperatures
Processing Flowability	Pa·s	0.1-1.0	Influences the fluidity and uniformity of materials during processing
Volatility	mg/m³	<10	The lower the better, avoid affecting product quality
Biotoxicity	LD50 (mg/kg)	>5000	Complied with international safety standards

Of course, the specific selection needs to be combined with actual application scenariosConduct a comprehensive assessment. For example, if the goal is for food contact materials, low mobility and high purity composite antioxidants should be given priority; if it is used in high temperature environments, its thermal stability and durability should be focused on.

5. Future development and prospects of composite antioxidants

With the advancement of technology and changes in social needs, compound antioxidants are developing towards more intelligent, personalized and environmentally friendly. The future composite antioxidants will no longer be limited to simple chemical compounding, but will incorporate more cutting-edge technologies, such as nanotechnology, biotechnology, etc., to achieve higher performance and lower costs.

In addition, artificial intelligence and big data analysis will also provide strong support for the research and development of composite antioxidants. By simulating the performance of different formulas under various conditions, researchers can quickly screen out the best solutions and significantly shorten the development cycle.

In short, as an important part of modern industry, composite antioxidants have unlimited development prospects. Let us wait and see and look forward to more exciting innovations in this field!