PZ-28 is a propylene imine tri-functional polyaziridine with a functionality of 2.8. PZ-28 is used as a cross-linker for both aqueous and non-aqueous coatings, inks, and adhesives to promote both physical and chemical properties. The methyl group attached to the aziridine ring provides a degree of steric hinderance, which allows a pot life of 12-24 hours in a formulation with a pH of 9-9.5. Therefore, PZ-28 is ideal for general purpose factory applied applications.
PZ-33 is an ethylene imine based tri-functional polyaziridine that is also used as a cross-linker for both aqueous and non-aqueous field and factory applied coatings and inks to promote both physical and chemical properties. With the highest level of functionality at 3.3, it yields the highest level of cross-link density of polyfunctional aziridines. However, due to the unsubstituted aziridine rings, the typical pot life of the PZ-33 is 4-8 hours in a formulation with a pH of 9-9.5. This grade is ideal for field or factory applied coatings where a faster dry time and greater cross-link density is desired. Also, the added hydroxyl group on this molecule allows PZ-33 to be easily dispersed into an aqueous coating, adhesive, or ink.
Typical Properties of Polyfunctional Aziridines
| Typical Properties | PZ-28 | PZ-33 |
|---|---|---|
| CAS Number | 64265-57-2 | 57116-45-7 |
| EC Number | 264-763-3 | 260-568-2 |
| Appearance | Slight amber clear liquid | Slight amber clear liquid |
| Aziridine Content, meq/g | 5.4-6.6 | 6.4-7.3 |
| Aziridine Functionality | 2.8 | 3.3 |
| Density @ 25° C g/ml | 1.05-1.09 | 1.15-1.20 |
| Viscosity, cp @ 25° | 100-300 | <4,000 |