# PolyurethaneRaw

> PolyurethaneRaw (https://polyurethaneraw.com) is a technical reference on polyurethane raw materials: polyols, isocyanates (MDI, TDI), prepolymers and additives, how they react, how to check them on delivery and how to source them.

Typical values (NCO content, OH number, viscosity, dosage) are general industry ranges, not product specifications; always use the supplier's technical data sheet for a specific grade.

## Guides
- [Polyurethane raw materials](https://polyurethaneraw.com/): Polyurethane raw materials explained: polyols, MDI and TDI, prepolymers and additives, with typical specs, a full material list and sourcing advice.
- [Polyols for polyurethane](https://polyurethaneraw.com/polyols/): Polyols for polyurethane explained: polyether, polyester, polymer and bio-based grades, OH value, functionality and how to choose one per application.
- [Isocyanates for polyurethane: MDI, TDI and prepolymers](https://polyurethaneraw.com/isocyanates-mdi-tdi/): Isocyanates for polyurethane: MDI, polymeric MDI, TDI, aliphatics and prepolymers, NCO content, isocyanate index, safe storage and EU training rules.
- [Polyurethane additives](https://polyurethaneraw.com/polyurethane-additives/): Polyurethane additives explained: catalysts, silicone surfactants, blowing agents, flame retardants and chain extenders, with typical dosages and fixes.
- [Polyurethane raw materials by application](https://polyurethaneraw.com/applications/): Which polyols, isocyanates and additives each application uses: rigid and flexible foam, footwear, coatings, adhesives and binders, in one clear table.

## Articles
- [How to choose a polyurethane raw material supplier: a 2026 checklist](https://polyurethaneraw.com/blog/how-to-choose-a-polyurethane-raw-material-supplier/): A 2026 buyer's checklist for choosing a polyurethane raw material supplier: documents, batch checks, technical support, logistics and red flags to avoid.
- [MDI vs TDI: choosing the right isocyanate](https://polyurethaneraw.com/blog/mdi-vs-tdi/): MDI vs TDI compared: structure, NCO content, volatility, handling, grades and typical applications, with a checklist for choosing the right isocyanate.
- [PIR vs PUR: which insulation foam fits your product?](https://polyurethaneraw.com/blog/pir-vs-pur-insulation-foam/): PIR vs PUR insulation foam compared: chemistry, isocyanate index, fire behaviour, lambda, friability and processing, plus a checklist for choosing.
- [Polyether vs polyester polyol: which one for your application?](https://polyurethaneraw.com/blog/polyether-vs-polyester-polyols/): Polyether vs polyester polyol compared on hydrolysis, strength, oil resistance, cold flexibility and cost, with a quick decision list for each application.
- [Polyurea vs polyurethane coatings: how to choose](https://polyurethaneraw.com/blog/polyurea-vs-polyurethane-coatings/): Polyurea vs polyurethane coatings compared: chemistry, cure speed, moisture tolerance, UV stability, equipment and cost, with a checklist for choosing.
- [Polyurethane mix ratio: how to calculate it, step by step](https://polyurethaneraw.com/blog/polyurethane-mix-ratio-calculation/): How to calculate a polyurethane mix ratio from OH value, NCO content and index, convert it to a volume ratio and estimate kilograms and drums for a job.
- [Polyurethane shoe sole raw materials: what goes into a PU sole](https://polyurethaneraw.com/blog/polyurethane-shoe-sole-raw-materials/): Polyurethane shoe sole raw materials explained: polyol blend and MDI prepolymer, polyester vs polyether soles, typical densities, processing and defects.
- [The true cost of cheap polyurethane raw materials](https://polyurethaneraw.com/blog/true-cost-of-cheap-polyurethane-raw-materials/): Why price per kg misleads: a total-cost model for polyurethane raw materials with a worked example, the hidden cost drivers and what to measure in a trial.

## Site
- [About and editorial policy](https://polyurethaneraw.com/about/)

## Optional
- [Full text of all pages](https://polyurethaneraw.com/llms-full.txt)