Fabricating APP-containing polyurethane
To simultaneously improve the compatibility, flame retardancy and mechanical properties of ammonium polyphosphate (APP) based polyurethane, an efficient and facile strategy was developed, in which hydroxyl-functionalized APP (HAPP) was synthesised through ion-exchange reaction between APP and 3-aminopropanol, and then utilised as a multiple-function excipient for solvent-free two-component polyurethane (2K-PU) by chemical cross-linking.
Significantly reducing heat and smoke
The curing behavior, mechanical and flame-retardant performances of HAPP cured 2K-PU, designating as 2K-PU/HAPP, were elaborately evaluated. Cone calorimeter results indicated that the conjugation of 15 wt% HAPP into 2K-PU significantly reduced the peak heat release rate (PHRR), total heat release (THR) and total smoke production (TSP) by 68.7%, 42.8% and 9.3%, respectively.
Potential for industrial application
Intriguingly, mechanical tests illustrated that the chemical incorporation of HAPP definitely improved the tensile strength of 2K-PU/HAPP while well-maintained the elongation at break, highlighting its attractive potential for industrial application. In addition, a flame-retardant mechanism for 2K-PU/HAPP was proposed. All aforementioned results distinctly demonstrate a feasible yet promising paradigm for fabricating APP-containing polyurethane.
The study is published in: Progress in Organic Coatings Volume 120, July 2018, Pages 88-99.
If you want to learn more about Polyurethanes and get a comprehensive overview on the technology you should visit the European Coatings Seminar Polyurethane Coatings. It will take place in September in Amsterdam, Netherlands and cover all important aspects like binders, 1k and 2k technology, hardeners and more.
Also, you may want to check out the European Coatings Seminar on Flame Retardant Coatings that will take place the next day, September 12, also in Amsterdam. This course will teach you what kind of flame retardant are available, how they work and many more important insights.