Are Nitrile Butadiene Rubber Rollers Toxic?

In modern industrial applications, the choice of rubber roller material is extremely critical, especially in industries such as food processing, packaging, printing, and medical, where the safety of rubber materials becomes a primary consideration.

Many people, when encountering or using nitrile butadiene rubber rollers (NBR rollers), ask a very common and important question:

"Are nitrile butadiene rubber rollers toxic?"

The definitive answer is: Nitrile butadiene rubber is non-toxic, and NBR rubber rollers are also non-toxic products.

Nitrile butadiene rubber (NBR) is an industrial synthetic rubber material copolymerized from acrylonitrile and butadiene, possessing excellent oil resistance, abrasion resistance, and mechanical stability. It is a chemically stable polymer and does not release toxic substances harmful to humans. Therefore, it is widely used in many industries.

This article will help you understand why NBR rubber rollers are a safe and reliable choice for industrial rubber rollers.

What exactly is NBR rubber roller made of? Does its structure produce toxicity?

To determine whether a material is toxic, it is first necessary to understand its origin and chemical structure.

What is Nitrile Butadiene Rubber (NBR) composed of?

Ntrile butadiene rubber is copolymerized from the following two monomers:

• Acrylonitrile (ACN)

• Butadiene (BD)

When these two molecules combine through a polymerization reaction, they form a stable rubber polymer, namely NBR (Nitrile Butadiene Rubber).

Its characteristics include:

• Stable molecular chains

• Resistant to decomposition

• No volatile harmful gases

• Free of heavy metals and harmful additives (from legitimate production)

The polymerized NBR molecular structure is non-toxic, which is a key reason why it can be used in many industries with high safety standards.

Is NBR in its polymer state toxic?

No.

Although some monomer components (such as butadiene) are somewhat toxic in their free state, the polymerized NBR is a stable solid material and does not release harmful substances.

This is similar to how chlorine and sodium are individually irritating, but when combined, they become table salt.

Similarly, NBR is a stable polymer and does not possess the toxicity of its monomeric components.

Therefore, NBR rubber rollers, as solid products, are non-toxic.

Why can we definitively say that "nitrile rubber rollers are non-toxic"? What is the scientific basis?

The non-toxicity can be determined from the following points:

1. NBR does not release harmful gases

Nitrile rubber generally remains stable in the range of room temperature to medium-high temperatures, without decomposition or releasing volatile substances containing toxicity.

Unlike rubbers containing high levels of chlorine or sulfur, it does not release chemical gases at high temperatures.

2. NBR does not contain inherently toxic structural groups

The toxicity of many toxic materials stems from:

• Chlorine-containing structures

• Phenolic structures

• Polycyclic aromatic hydrocarbon structures

• Heavy metal additives

The basic structure of NBR is composed of carbon, hydrogen, and nitrogen, and it does not contain the aforementioned risky groups, making it chemically stable.

3. No Toxic Additives Required During Processing

Regularly manufactured NBR rubber rollers do not use the following in their formulation:

• Toxic plasticizers

• Accelerators harmful to humans

• Heavy metal additives

• Highly volatile chemical solvents

Therefore, the finished material maintains a high level of safety.

4. Multi-Industry Certifications Recognize Nitrile Rubber as a Safe Material

Many international standards list nitrile rubber as permissible for use in:

• Food machinery parts

• Beverage equipment seals

• Medical device accessories

• Pharmaceutical industry conveyor rollers

This further proves the non-toxicity of NBR.

Will NBR rubber rollers release harmful substances during use?

Many users worry that rubber rollers may release toxicity during use due to friction, heating, or aging. This will be addressed below.

Will there be toxic dust during friction?

NBR rubber rollers do not produce toxic dust during normal operation.

Unlike some resins or chlorine-containing materials, it does not produce hazardous particles after friction.

All rubber powder produced during wear is inert and poses no direct toxicity to humans.

Will NBR release toxic gases when heated?

Within the normal operating temperature range (approximately 120°C), NBR rubber rollers do not produce harmful gases.

Only under extremely abnormal conditions, such as overheating to the decomposition temperature (far above normal operating values), will any polymer material decompose. Therefore, this is not due to the product's inherent toxicity, but rather to misuse.

Will toxic substances be released during aging?

The main changes that occur during the aging of nitrile rubber are:

• Molecular chain breakage

• Hardening

• Decreased elasticity

These changes are not accompanied by the release of harmful substances. Aged NBR remains a safe and inert material.

Can NBR rubber rollers be used in equipment that comes into contact with food? Is it safe?

NBR is permitted in many countries to be manufactured into food-grade rubber parts, and can be used for:

• Food conveyor rollers

• Beverage bottling equipment components

• Food packaging rollers

• Food contact seals

This indicates that nitrile rubber itself has sufficient safety to meet high-standard industry requirements.

Do NBR rubber rollers contain carcinogens or harmful chemical additives?

Many customers are concerned about whether rubber is carcinogenic and contains harmful components such as PAHs (polycyclic aromatic hydrocarbons).

Nitrile rubber itself does not contain carcinogens.

The molecular structure of NBR does not contain structures with carcinogenic risks, such as:

• Benzene ring polymerization systems

• Chlorinated groups

• Heavy metal elements

Therefore, it is not structurally carcinogenic.

Additives in the formulation can be completely non-toxic.

Reputable NBR rubber roller manufacturers will:

• Use environmentally friendly vulcanization systems

• Avoid using aromatic oils

• Avoid process materials containing PAHs

• Use non-toxic stabilizers

Therefore, non-toxicity is ensured from structure to formulation.

Are nitrile rubber rollers still considered safe in industrial environments?

Industrial environments may include factors such as oils, chemical reagents, and heat, so the impact of the environment on the material needs to be assessed.

Will contact with oils release toxicity?

No.

NBR has extremely high oil resistance; oil will not damage its structure or trigger toxic reactions.

Will contact with chemicals produce harmful substances?

Contact with most common neutral or weakly polar chemicals will not produce harmful side effects.

However, contact with strong solvents (such as ketones, ethers, and strong aromatics) may cause swelling, but this swelling is a physical change and does not produce toxic substances.

Will high-speed operation produce an irritating odor?

NBR rubber rollers do not release irritating chemical gases. Odors are usually caused by external substances such as equipment lubricants and plasticizers, rather than the release of toxicity from the rubber itself.

What are the key advantages of nitrile rubber rollers being considered non-toxic?

To more systematically understand the safety of NBR rubber rollers, it can be summarized from the following perspectives:

1. Safe molecular structure

NBR is a stable polymer with a high decomposition temperature, is not easily volatile, and does not contain toxic structures.

2. Insoluble in water and does not leach hazardous substances

NBR is insoluble in water and does not leach migratable toxic substances, therefore it is safe for users.

3. Safe Processing, Free of Harmful Additives

Modern NBR formulations utilize environmentally friendly systems, avoiding the risky additives that may have been present in earlier rubbers.

4. Long Service Life, Fewer Material Degradation Byproducts

NBR's oil and abrasion resistance reduces aging, and its aging products are inert dust and non-toxic.

5. Suitable for Demanding Industries

Approvals from industries such as food, medical, and water treatment demonstrate its reliable safety.

How to Determine if an NBR Rubber Roller is Truly Non-Toxic?

While the material itself is non-toxic, the non-toxicity of the finished product depends on the manufacturer's process.

When choosing NBR rubber rollers, consider the following:

1. Does it use an environmentally friendly vulcanization system?

Formulations containing nitramine accelerators are safer.

2. Has it passed relevant testing?

For example:

• RoHS

• REACH

• Food-grade testing (if required)

• PAHs restriction testing

3. Do you avoid using aromatic plasticizers?

Environmentally friendly rubber rollers generally use non-aromatic oils.

4. Do you provide Material Safety Data Sheets (MSDS)?

Reputable companies provide complete information, ensuring greater control over safety.

Do you provide dynamic balancing for rollers?

Yes. Dynamic balancing is a crucial part of our process as a precision roller manufacturer. Our balancing equipment ensures each roller operates smoothly at high rotational speeds, preventing vibration, uneven tension, and wear on connected machinery. This service is particularly important for printing, film casting, and high-speed coating applications where stability and accuracy are essential.