SCI和EI收录∣中国化工学会会刊

Chinese Journal of Chemical Engineering ›› 2019, Vol. 27 ›› Issue (7): 1735-1743.DOI: 10.1016/j.cjche.2019.04.023

• Materials and Product Engineering • Previous Articles    

Microencapsulated ammonium polyphosphate by polyurethane with segment of dipentaerythritol and its application in flame retardant polypropylene

Shouwu Yu1,2, Shujuan Xiao2, Zewen Zhao2, Xiaowen Huo2, Junfu Wei1   

  1. 1 School of Material Science and Engineering, Tianjin Polytechnic University, Tianjin 300387, China;
    2 College of Materials Science and Engineering, North China University of Science and Technology, Tangshan 063009, China
  • Received:2019-02-14 Online:2019-10-14 Published:2019-07-28
  • Contact: Junfu Wei

Microencapsulated ammonium polyphosphate by polyurethane with segment of dipentaerythritol and its application in flame retardant polypropylene

Shouwu Yu1,2, Shujuan Xiao2, Zewen Zhao2, Xiaowen Huo2, Junfu Wei1   

  1. 1 School of Material Science and Engineering, Tianjin Polytechnic University, Tianjin 300387, China;
    2 College of Materials Science and Engineering, North China University of Science and Technology, Tangshan 063009, China
  • 通讯作者: Junfu Wei

Abstract: Dipentaerythritol (DPER), 4, 40-diphenylmethanediisocyanate (MDI) and melamine (MEL) are used as raw materials to microencapsulate ammonium polyphosphate (MAPP) in situ polymerization. The MAPP is characterized by Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and thermal gravimetric analysis (TGA). The results show that the coating operation can effectively improve water resistance of ammonium polyphosphate (APP), and MAPP has higher residual rate than that of APP after combustion. The flame retardant action of MAPP and APP in polypropylene (PP) is investigated by the limited oxygen index (LOI), vertical burning test (UL-94), TGA, SEM, and cone calorimeter test (CCT). The LOI value of the PP/MAPP composite at the same loading is higher than that of PP/APP composite. UL 94 ratings of PP/MAPP composites are raised to V-0 at 20 wt% loading. The results of CCT also show that MAPP is more efficient than APP. The morphological structures observed by digital photos and SEM demonstrated that MAPP could be promoted to form the continuous and compact intumescent char layer. The flame retardant mechanism of PP/MAPP is also discussed.

Key words: Microencapsulation, Solubility, Ammonium polyphosphate, Pyrolysis, Flame retardant, Stability

摘要: Dipentaerythritol (DPER), 4, 40-diphenylmethanediisocyanate (MDI) and melamine (MEL) are used as raw materials to microencapsulate ammonium polyphosphate (MAPP) in situ polymerization. The MAPP is characterized by Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and thermal gravimetric analysis (TGA). The results show that the coating operation can effectively improve water resistance of ammonium polyphosphate (APP), and MAPP has higher residual rate than that of APP after combustion. The flame retardant action of MAPP and APP in polypropylene (PP) is investigated by the limited oxygen index (LOI), vertical burning test (UL-94), TGA, SEM, and cone calorimeter test (CCT). The LOI value of the PP/MAPP composite at the same loading is higher than that of PP/APP composite. UL 94 ratings of PP/MAPP composites are raised to V-0 at 20 wt% loading. The results of CCT also show that MAPP is more efficient than APP. The morphological structures observed by digital photos and SEM demonstrated that MAPP could be promoted to form the continuous and compact intumescent char layer. The flame retardant mechanism of PP/MAPP is also discussed.

关键词: Microencapsulation, Solubility, Ammonium polyphosphate, Pyrolysis, Flame retardant, Stability