Tackifiers, also known as adhesive agents, tackifiers, or **adhesive agent for lubricants**, are additives that provide two types of properties to the lubricants or greases to which they are added. Due to the chemical bonds between atoms, they can provide **adhesion** to the surface where they are applied or **cohesion**, i.e., forces that exist between the molecules of greases, lubricants, or certain particular fluids.
In the lubricant industry, they are also known as Polymer Adhesive Tackifiers, especially when referring to polymeric additives designed to improve the adhesiveness, stringiness, and permanence of the lubricant on metal surfaces.
What are these agents?
These additives are polymers that impart adhesiveness or consistency to the base fluid. Adhesiveness is considered a composite property, determined by cohesive and adhesive forces, viscosity, and other factors such as molecular weight and the concentration of polymeric additives used in the formulation of said additives. Cohesive forces allow the lubricant to remain united as a single mass, while adhesive forces make it remain on the surfaces to be lubricated.
In other words: a good adhesive agent helps prevent the lubricant from being lost through dripping, splashing, or centrifugation, and keeps it longer at the point where it needs to act. This is especially important in open or exposed applications, such as chains, guides, cables, open gears, chainsaws, textile machinery, or systems where reducing oil mist is desired.
The viscoelastic properties of polymer solutions depend on the polymer concentration and various molecular parameters determined by their chemical structure. The most important parameters are the molecular weight of the polymer and, to a certain extent, the molecular weight distribution, as well as the structure of the polymer chains. Another important parameter is the viscosity of the base.
The most used polymers as tackifiers are high molecular weight polyisobutylene (PIB) and olefin copolymer (OCP). OCPs provide lower stringiness lengths than PIB. However, the shear stability (SS) of OCPs is much higher.
Types of tackifiers for lubricants
Not all tackifiers work the same. To correctly select an **adhesive agent for lubricants**, it is useful to differentiate between their base chemistry and the type of application for which they were designed. From a chemical point of view, the most commonly used tackifiers in industrial lubricants are high molecular weight polymers, capable of providing adhesiveness, cohesion, and stringiness to the formulated oil or grease.
Main chemistries used as tackifiers
- PIB-based tackifiers
Polyisobutylene (PIB)-based tackifiers are among the most common chemistries in industrial lubrication when high stringiness and good adhesion are sought. PIB helps generate that characteristic “string” effect of many adhesive lubricants. That is why it is frequently used in oils for chains, guides, cables, chainsaws, open gears, and other applications where the lubricant must remain on the surface and resist dripping or splashing.Its main advantage is the high adhesiveness it can provide even at low concentrations. However, its behavior under shear and temperature must be carefully evaluated, especially in demanding applications.
- OCP-based tackifiers
Olefin copolymer (OCP)-based tackifiers offer an interesting alternative when seeking a better balance between adhesiveness and mechanical stability. In general, OCPs generate less stringiness than PIBs, but they usually offer better shear stability. This can be important in formulations subjected to continuous mechanical stress, where the lubricant needs to maintain its properties for longer.OCPs can be suitable in industrial oils, lubricating greases, and formulations where additive durability is as important as initial stringiness.
- Other polymeric tackifiers
In addition to PIB and OCP, there are other Polymer Adhesive Tackifiers developed with specific polymeric structures to adjust particular properties, such as compatibility with synthetic oils, thermal resistance, cold behavior, mist reduction, or ease of incorporation during manufacturing.In these cases, the selection should not be based only on the ability to generate stringiness, but also on compatibility with the base oil, system stability, and expected performance in the final application.
Tackifiers by application or formulation requirement
Once the chemistry has been defined, it is also important to consider the type of application. Some tackifiers are designed to meet specific formulation requirements.
- High-temperature tackifiers
These are used in lubricants and greases operating under demanding thermal conditions. They must provide tackiness without compromising the thermal and oxidative stability of the finished product. They are particularly relevant in formulations based on PAOs, Group III oils, or other synthetic base stocks where enhanced resistance to degradation is required.
- Bio-based tackifiers or tackifiers for more sustainable formulations
These are used in lubricants intended for environmentally sensitive applications, such as chain oils, guide lubricants, forestry and agricultural applications, or areas where reducing the environmental impact of the formulation is a priority. In such cases, the tackifier should be evaluated as part of the overall formulation, especially when the objective is to comply with criteria such as the Ecolabel or to align with the LuSC list.
- Tackifiers for water-based systems
There are tackifying agents specifically designed for water-based fluids or emulsions. Their function is to provide viscosity, tackiness, and system stability without compromising ease of application or compatibility with the aqueous medium. They can be of interest in certain industrial formulations where a combination of lubricity, adhesion, and stable performance in water is required.
- Food-grade tackifiers
In applications where incidental food contact may occur, it is necessary to select tackifiers that comply with the relevant regulatory requirements. These products can be used in food-grade lubricants, provided that the complete formulation meets all applicable standards and specifications.
How to approach selection
Chemistry defines the basic behavior of the tackifier: stringiness, adhesiveness, shear stability, and compatibility. The application defines the practical requirements: temperature, pumpability, water resistance, regulation, biodegradability, mist reduction, or surface permanence.
Therefore, the best selection is not always the tackifier that generates the most “stringiness”. The goal is to find the right balance between adhesiveness, stability, compatibility, and in-service performance.
What are the benefits?
Tackifiers provide adhesion in lubricants and consistency in greases, to prevent lubricant dripping, inhibit dispersed mist in lubricants, and increase lubrication time in machinery. Among their most relevant benefits are:
- Better adhesion of the lubricant to metal surfaces.
- Reduced dripping.
- Less loss due to splashing or centrifugation.
- Greater permanence of the lubricant film.
- Mist reduction in certain applications.
- Improved consistency in greases.
- Greater cleanliness in the work environment.
- Optimized lubricant consumption.
- Greater protection in open, exposed, or vibration-prone applications.
- In short, an adhesive agent not only modifies the appearance of the lubricant. Well selected, it can improve its in-service behavior and help the lubricant film stay where it is really needed.
What are its applications?
Some typical applications where tackifiers are added include:
- Chain and wire rope oils: the lubricant must withstand continuous movement, centrifugal forces and, in some cases, elevated temperatures. A tackifier helps reduce dripping and improves oil retention on the chain.
- Slideway and guide oils: tackifiers help improve the adhesion of the lubricant on the metal surface, reducing losses and promoting a more stable lubricating film.
- Corrosion preventives.
- Textile machinery oils.
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- Open gear oils: the lubricant is exposed to load, dust, vibration and harsh environmental conditions. The use of a tackifier helps keep the lubricant in the contact zone and reduce losses due to fling-off.
- Lubricating greases: tackifiers can improve cohesion, stringiness and the ability of the product to remain at the lubrication point. This is particularly useful when the grease must withstand vibration, moisture or repetitive movements.
- Anti-mist lubricants and metalworking fluids: in certain applications, tackifiers help reduce oil mist formation. This contributes to improving workplace cleanliness, reducing lubricant losses and limiting the dispersion of the product into the environment.
- Lubricants for agricultural, forestry and exposed industrial applications.
- Pneumatic tools: the lubricant must circulate properly but also adhere to internal surfaces to protect components. An appropriate tackifier can help improve this retention without compromising system performance.
Compatibility of tackifiers with base oils and other additives
Compatibility is one of the most important factors when selecting a tackifier or Polymer Adhesive Tackifier. A tackifying agent must properly dissolve in the base oil and remain stable both during storage and use.
If good compatibility is not achieved, problems such as turbidity, phase separation, loss of efficiency, viscosity changes or instability in the final formulation may occur.
During formulation, it is advisable to evaluate:
- Compatibility with mineral oils, PAO, esters, white oils, vegetable oils or biodegradable base stocks, as well as with other formulation additives.
- Shear stability.
- Low- and high-temperature behavior.
In industrial lubricants, the tackifier does not work alone. It coexists with EP/AW additives, antioxidants, corrosion inhibitors, friction modifiers, antifoam agents and other components. Therefore, selection should be made considering the complete formulation, not only the tackiness property.
What should be kept in mind?
Like other polymers, tackifiers can lose their properties if the polarity of the diluent is changed. Generally, this problem arises when a polymer is mixed with another more polar additive, such as a motor oil package or a sulfonate-based surfactant. Incompatibility can be avoided by considering the mixing sequence: when mixing a polymeric additive and a polar additive, always fully dissolve one additive in the lubricant base before starting to add the other.
More viscous additives can be difficult to mix with low viscosity diluents. Poor mixing can lead to incompatibility when other additives are added. If agitation is insufficient for good mixing, the easiest solution is to heat the adhesive before mixing.
Thermal decomposition: polyisobutylene tackifiers begin to decompose above 100 °C.
How to choose the right tackifier
The selection of a tackifier depends on the application and the type of formulation. Before selecting an adhesive agent for lubricants, it is advisable to analyze:
- Type of base oil used.
- Desired final viscosity.
- Operating temperature.
- Required level of tackiness.
- Shear stability.
- Need to reduce dripping, fling-off or mist formation.
- Compatibility with other additives.
- Regulatory or food-grade requirements.
- Ease of handling during manufacturing.
A tackifier that generates the highest level of stringiness is not always the most suitable choice. In some applications, excessive stringiness can hinder pumpability, affect lubricant behavior or create issues in automatic systems. Therefore, the goal is not to add more tackiness, but to find the right balance between adhesion, stability, viscosity, compatibility and performance. It is a bit like adjusting salt in a recipe: too little goes unnoticed, too much ruins the dish.
Tackifiers in high-performance formulations
Lubricant formulators are increasingly seeking solutions that improve efficiency, reduce consumption, and extend relubrication intervals. In this context, tackifiers play a very relevant role. Their use can be especially interesting in formulations for high-load industrial lubricants, chain oils, guide oils, industrial greases, open gears, anti-mist lubricants, and applications in mining, steel, paper, cement, or heavy industry.
The challenge is to select the right adhesive agent for each system. A tackifier must provide adhesiveness without compromising the stability, pumpability, or compatibility of the final product.
Contact our specialists to learn about our catalog of tackifiers.
At Lumar Química, we work with solutions designed to help lubricant formulators and manufacturers improve the adhesion, stability, and performance of their products, adapting the selection of the tackifier to each industrial application.
