Prepolymer
Prepolymer , sometimes also written prepolymer , is usually a collective term for reactive oligomers that are used to produce polymers ( macromolecules ). They are preliminary products that, in contrast to the end product, can still be soluble or meltable. Prepolymers allow the production of block copolymers or shaping processing before crosslinking leads to a thermoset state as the polymerization proceeds. Often, two prepolymers that are to form a polymer in the future are designed in such a way that one prepolymer carries at least two identical reactive functionalities ( e.g. a diisocyanate ) of one type, the other prepolymer two functionalities of a suitable reaction partner (e.g. a diol ) and only after Mixing the prepolymers leads to the end product (here a polyurethane ).
Individual evidence
- ↑ Entry on prepolymers. In: Römpp Online . Georg Thieme Verlag, accessed on November 13, 2014.
- ↑ Entry on pre-polymer molecule . In: IUPAC Compendium of Chemical Terminology (the “Gold Book”) . doi : 10.1351 / goldbook.P04818 Version: 2.3.3.