To improve the thermal stability of polyurethane foam, the pre-trimerized polyurethane-polyisocyanurate foam (PT-PUIRF) was prepared using pre-trimerized isocyanurate prepolymer (PT). Herein, PT was synthesized by “pre-trimerization” using polymeric methylene diphenyl diisocyanate (PMDI) and trimerization catalyst. Thermal stabilities and mechanical properties of PT-PUIRF and polyurethane-polyisocyanurate foam (PUIRF) were evaluated via TGA and UTM. Also, the flame retardancy of these foams was investigated by limiting oxygen index (LOI) and vertical burning test (UL94 V). FTIR results showed that PT-PUIRF contained more isocyanurate than PUIRF, indicating that PT-PUIRF had higher heat resistance and flame retardancy than PUIRF

본 연구는 폴리우레탄 폼(polyurethane foam)의 열 안정성을 향상시키기 위해 polymeric methylene diphenyl diisocyanate(PMDI)를 pre-trimerization 시켜 pre-trimerized isocyanurate prepolymer(PT, PMDI trimer)를 합성한 후 이를 이용하여 pre-trimerized polyurethane polyisocyanurate foam(PT-PUIRF)을 합성하였다. TGA와 LOI, UL94 V 및 만능시험기를 사용하여 합성된 PT-PUIRF와 polyurethane-polyisocyanurate foam(PUIRF)의 열 안정성과 기계적 물성을 비교하였다. FTIR을 통해 PT-PUIRF에 포함되어 있는 이소시아누레이트의 함량이 PUIRF보다 높은 것으로 밝혀졌으며, 이로 인해 PT-PUIRF가 PUIRF보다 높은 내열성과 난연성을 나타냄을 알 수 있었다

Keywords: polyurethane polyisocyanurate foam, pre-trimerization, polymeric methylene diphenyl diisocyanate trimer, isocyanurate prepolymer, thermal stability