Smoke suppression performance of polyurethane composites containing microencapsulated melamine polyphosphate
A novel microencapsulated flame retardant containing melamine polyphosphate (MPP) and 4,4′-oxydianiline-formaldehyde (OF) resin as a core-shell material was synthesized using in situ polymerization. The flame retardant was added to polyurethane (PU) to improve the fire suppression performance of resulting materials. Polyurethane was modified by silane, which was called as Si-PU and MPP was microencapsulated by OF resin, which was OFMPP. The results indicated that the smoke obscuration index (SOI) values of Si-PU, Si-PU/MPP 30% and Si-PU/OFMPP 30% were 6.59, 3.04 and 1.16, respectively, which indicated that the addition of flame retardants causes a significant downward trend in SOI values. The SOI value of Si-PU/OFMPP 30% was lower than that of Si-PU/MPP 30%, indicating that the microencapsulated OFMPP achieved smoke suppression.