Oxidised wax is a functional wax whose chemistry has been modified to introduce polar groups. That additional polarity can improve emulsifiability, compatibility, lubrication, release and surface-protection behaviour in selected industrial systems.
The term covers a broad family rather than one fixed specification. Oxidised polyethylene, Fischer-Tropsch and other hydrocarbon waxes can differ in molecular weight, acid value, viscosity, hardness and melting range. These differences influence how a grade processes and what it contributes to the final product.
This guide explains why oxidation changes wax performance, where oxidised wax is used and what information helps identify an appropriate grade.
In this oxidised wax guide
- Why added polarity changes performance
- Six industrial formulation benefits
- The acid value, thermal and viscosity variables to compare
- A representative application-trial plan
- Answers to common grade-selection questions
What is oxidised wax?
Oxidation introduces oxygen-containing functional groups into a hydrocarbon wax. The process changes the wax from a largely non-polar material into one with a controlled degree of polarity.
Acid value is commonly used as one indicator of this modification. It should not be treated as the only selection criterion, but it helps technical teams compare the functional character of related grades.
The selected raw material and processing conditions also matter. Molecular weight, oxidation level and solidification route affect viscosity, melting behaviour, hardness and the physical form in which the product can be supplied.
Clariant’s technical information for oxidised polyethylene waxes shows how grades can combine high melting behaviour with emulsifiability, lubrication, anti-sticking or surface-protection functions. These examples also demonstrate why application trials remain essential.
Why does polarity matter?
Non-polar waxes have limited interaction with water and many polar ingredients. Introducing polar groups can make the wax easier to emulsify or more compatible with resins, pigments, fillers and other formulation components.
The optimum polarity depends on the application. Too little may not deliver the required compatibility. Too much may change water sensitivity, viscosity or surface behaviour. A grade must therefore be assessed within the full formulation and process.
| Selection variable | What it helps describe | Why it matters |
|---|---|---|
| Acid value | Degree of functional oxidation | Emulsifiability, compatibility and interaction with polar ingredients |
| Viscosity or molecular weight | Melt-flow and wax-body characteristics | Processing, lubrication, dispersion and film contribution |
| Drop or congealing point | Thermal incorporation and service range | Mixing window, storage stability and end-use performance |
| Physical form | Powder, pastille, slab or drum supply | Dosing, melting time, handling and warehouse efficiency |
6 industrial benefits of oxidised wax
1. Easier emulsification
Oxidised wax can be converted into stable water-based emulsions or dispersions more readily than many non-polar hydrocarbon waxes. This opens the door to water-based coatings, polishes, release products and other systems that need wax functionality without a predominantly solvent-based carrier.
Surfactant selection, pH, shear and cooling conditions still control emulsion quality. Emulsifiability does not remove the need for a disciplined production process.
2. Lubrication in plastics processing
Selected oxidised waxes can act as internal or external lubricants in PVC and other polymer systems. They may improve flow, reduce sticking or influence fusion and release behaviour.
The balance is application-specific. Excess external lubrication can delay fusion, while the wrong internal lubrication can affect melt strength or finished properties. Processing trials should monitor torque, pressure, fusion time, surface finish and output rate.
3. Improved pigment and filler dispersion
Polarity can help certain oxidised waxes wet pigments or fillers and support more even distribution in masterbatch, coatings or polymer compounds. Better dispersion can contribute to colour consistency, process stability and surface quality.
Results depend on the pigment surface, carrier resin and processing temperature. Compare the wax against the complete pigment package rather than in isolation.
4. Release and anti-sticking performance
Oxidised waxes may function as release agents in thermosets, engineering resins, rubber and other processes. They can also provide anti-sticking behaviour during extrusion or moulding.
The additive must release effectively without causing plate-out, poor printability, weak adhesion or an unacceptable surface film.
5. Surface protection and hydrophobic effects
In polishes, paper treatments, textiles, leather and protective coatings, oxidised wax can support gloss, slip, water repellency or pore sealing. Harder grades may provide a durable protective effect, while more flexible grades may suit substrates that bend or move.
Test water resistance, gloss, coefficient of friction and appearance after realistic ageing and handling.
6. Functional coatings and corrosion-support systems
Oxidised waxes can be used in coatings where controlled film structure, water resistance, slip or compatibility contributes to protection. Cerax includes anti-corrosion applications among the uses considered for its Ceranox range.
Wax should be treated as one part of the protection system. Substrate preparation, binder choice, pigment package, film thickness and curing conditions remain critical.
Important oxidised wax selection factors
Acid value
Acid value helps describe the level of functionalisation and can affect emulsification and compatibility. Compare values using consistent test methods and relate them to application results.
Viscosity and molecular weight
These properties influence melt processing, dispersion, lubrication and the strength of the wax contribution. Higher viscosity is not automatically better. The grade must fit the available equipment and target behaviour.
Drop point or congealing point
Thermal properties determine how the wax is incorporated and how it behaves in storage and service. Confirm that the processing temperature provides adequate mixing without damaging other ingredients.
Hardness and flexibility
Hard waxes may support scratch resistance and anti-blocking. More flexible grades may suit polishes, leather, paper or formulations that must tolerate movement.
Physical delivery form
Powder, pastilles, slabs and drum stock affect handling, dosing, melting time and warehouse efficiency. Cerax can align solidification form with customer processing and supply requirements for suitable Ceranox products.
Regulatory and safety requirements
Request the technical data sheet and safety data sheet for the exact grade. Food-contact, personal-care and other regulated applications require separate confirmation based on the product, use level and applicable market.
How to plan an application trial
Define the current material, dosage, processing conditions and failure you want to solve. Compare a control with several candidate grades or addition levels. Measure both the primary target and possible side effects.
For polymer processing, track fusion, torque, release and surface quality. For coatings and polishes, evaluate stability, application, drying, gloss, slip, water resistance and abrasion. For emulsions, include particle size, viscosity and accelerated storage.
What to send Cerax with an enquiry
Provide the application, current wax, processing temperature, binder or polymer, target acid value if known, performance requirements and preferred physical form. Include sample quantities, annual demand and relevant compliance needs where possible.
The Ceranox range reflects Cerax’s experience in developing and producing oxidised waxes for emulsions, PVC lubrication, coatings, polishes and other industrial uses. Explore the Cerax oxidised wax range or discuss custom blends when the requirement falls between standard grades.
Frequently asked questions about oxidised wax
Open a question to see the practical answer.
Why is wax oxidised?
Controlled oxidation introduces polar functional groups. This can improve emulsifiability, compatibility, pigment or filler interaction, lubrication, release and surface behaviour.
How is oxidised wax different from non-oxidised wax?
Oxidised wax has greater polarity and is commonly described using acid value as well as viscosity and thermal properties. That can change how it interacts with water and polar formulation ingredients.
What does acid value tell me?
Acid value indicates the level of acidic functional groups and helps compare related grades. It is useful for shortlisting, but it does not predict finished performance on its own.
What is oxidised wax used for?
Applications include wax emulsions, PVC and polymer lubrication, pigment or filler dispersion, release systems, polishes, protective treatments and functional coatings.
How should I select an oxidised wax grade?
Start with the required function and process, then compare chemistry, acid value, viscosity, thermal range, hardness, delivery form and regulatory documentation before application trials.
Discuss an oxidised wax application
Send Cerax the application, current wax, binder or polymer, processing temperature, target function and preferred delivery form to speed up technical selection.
Function first, specification second
Oxidised wax can add valuable polarity and surface performance, but the best specification is the one proven in the customer’s process. Acid value, viscosity and melting behaviour provide a useful shortlist. Application trials determine whether the grade actually delivers.
Start with a clear function, share the real processing constraints and evaluate the full formulation. This creates a faster route from technical discussion to a repeatable production result.