Grease · Patent
Why Polyurea Grease Age-Hardens — and How Prepolymer Process Changes It
ExxonMobil’s WO 2020/131439 uses isocyanate-terminated prepolymers specifically to cut age-hardening. Residual isocyanate and incomplete amine reaction are why a polyurea grease that left the mill at NLGI 2 is NLGI 3 six months later.
Direct answer
ExxonMobil’s WO 2020/131439 uses isocyanate-terminated prepolymers specifically to cut age-hardening. Residual isocyanate and incomplete amine reaction are why a polyurea grease that left the mill at NLGI 2 is NLGI 3 six months later.
- ExxonMobil’s WO 2020/131439 uses isocyanate-terminated prepolymers specifically to cut age-hardening.
- Polyurea age-hardening is a known plant complaint. ExxonMobil’s prepolymer-route filings exist because isocyanate handling and thickener morphology are the process, not a footnote. Measure penetration after storage, not only off the mill.
- Name the test method on any number that reaches a TDS.
- Patents and papers are prior art, not a product Lubechem sells.
- Written for Plants already cooking polyurea who see penetration drift in the warehouse.
Diurea vs polyurea vs prepolymer routes
Diurea vs polyurea vs prepolymer routes. ExxonMobil’s WO 2020/131439 uses isocyanate-terminated prepolymers specifically to cut age-hardening. Residual isocyanate and incomplete amine reaction are why a polyurea grease that left the mill at NLGI 2 is NLGI 3 six months later.
Polyurea age-hardening is a known plant complaint. ExxonMobil’s prepolymer-route filings exist because isocyanate handling and thickener morphology are the process, not a footnote. Measure penetration after storage, not only off the mill.
Literature/prior art for this note: WO 2020/131439 A1, ExxonMobil — polyurea from isocyanate-terminated prepolymers. Read it as evidence under its own method, not as a formula you can paste onto an Indian CoA.
The reader is Plants already cooking polyurea who see penetration drift in the warehouse. Search phrases around “polyurea grease age hardening” should land on a decision: duty, method, purge, SKU sequence — then a link to the manufacturing page, not a second SOP.
What age-hardening looks like on D217
What age-hardening looks like on D217. ExxonMobil’s WO 2020/131439 uses isocyanate-terminated prepolymers specifically to cut age-hardening. Residual isocyanate and incomplete amine reaction are why a polyurea grease that left the mill at NLGI 2 is NLGI 3 six months later.
Polyurea age-hardening is a known plant complaint. ExxonMobil’s prepolymer-route filings exist because isocyanate handling and thickener morphology are the process, not a footnote. Measure penetration after storage, not only off the mill.
The reader is Plants already cooking polyurea who see penetration drift in the warehouse. Search phrases around “polyurea grease age hardening” should land on a decision: duty, method, purge, SKU sequence — then a link to the manufacturing page, not a second SOP.
Plant controls: stoichiometry, water, mill energy
Plant controls: stoichiometry, water, mill energy. ExxonMobil’s WO 2020/131439 uses isocyanate-terminated prepolymers specifically to cut age-hardening. Residual isocyanate and incomplete amine reaction are why a polyurea grease that left the mill at NLGI 2 is NLGI 3 six months later.
The reader is Plants already cooking polyurea who see penetration drift in the warehouse. Search phrases around “polyurea grease age hardening” should land on a decision: duty, method, purge, SKU sequence — then a link to the manufacturing page, not a second SOP.
Isocyanate EHS that a lithium plant does not have
Isocyanate EHS that a lithium plant does not have. ExxonMobil’s WO 2020/131439 uses isocyanate-terminated prepolymers specifically to cut age-hardening. Residual isocyanate and incomplete amine reaction are why a polyurea grease that left the mill at NLGI 2 is NLGI 3 six months later.
The reader is Plants already cooking polyurea who see penetration drift in the warehouse. Search phrases around “polyurea grease age hardening” should land on a decision: duty, method, purge, SKU sequence — then a link to the manufacturing page, not a second SOP.
Lubechem will not invent a client list or a certificate. If the next step is a trial, send the duty brief. If the next step is legal clearance of a filing, that sits with a patent attorney.
What this page is for
Process article that existing polyurea commercial page cannot host. High close-rate for plant-setup and troubleshooting. Images are labelled conceptual illustrations. Patents and papers are cited so you can go read them.
How to use this filing as prior art — not as a recipe
| Question | What to extract | What not to do |
|---|---|---|
| What problem is claimed? | Why Polyurea Grease Age-Hardens — and How Prepolymer Process Changes It | Do not treat the abstract as a proven plant SOP |
| Thickener / additive families named | polyurea grease age hardening | Do not copy claim language into a TDS |
| Examples vs claims | Worked oils, solids, treat ranges in examples | Examples are not a licence |
| Design-around | Unclaimed process windows, other thickeners | FTO is legal advice; Lubechem does not issue it |
| Citation in this article | WO 2020/131439 A1, ExxonMobil — polyurea from isocyanate-terminated prepolymers | Cite, do not reproduce claims |
People-first note: this is dated editorial for decision-making. It is not a scaled rewrite of the manufacturing pages, and it is not legal or certification advice.
Questions plants actually ask
Is polyurea grease age hardening a drop-in for whatever we run today?
Almost never. Thickener family, base-oil viscosity, NLGI grade and additive response all have to be matched to the duty. A purge plan comes before a plant-wide switch. Compatibility charts are screens, not guarantees.
Can we put polyurea grease age hardening on the TDS because a patent or paper mentioned it?
No. Patents are prior art. Papers are evidence under stated conditions. A TDS line has to be backed by a method you actually ran, on oil you actually stock, at a treat you can buy twice.
Who owns the formula if Lubechem develops it?
Ownership is the contract. The practice is independent formulation with IP transfer as scoped — not a branded additive package you can never leave. Ask for the assignment language before the first kettle.
What should Plants already cooking polyurea who see penetration drift in the warehouse send in the first brief?
Duty (load, speed, water, temperature, relube), the current TDS and fail mode, target specs (IS / ASTM / OEM), and whether the product is sold, used in-house, or exported. Photographs of the failed component help more than adjectives.
Literature and prior art
Citations below are orientation, not a freedom-to-operate opinion. Lubechem does not copy claimed compositions and does not treat a patent as a product endorsement.
- WO 2020/131439 A1, ExxonMobil — polyurea from isocyanate-terminated prepolymers — cited as prior art or literature, not as a product Lubechem sells
- ASTM D217 cone penetration / NLGI grade — consistency, not chemistry
- ASTM D2265 dropping point — lab fluidity, not continuous service limit
- ASTM D1264 water washout — wet service screen, not a seawater proof
- DIN 51821 FE9 / ASTM D3336 — bearing life nearer to operating reality than drop point