阻燃剂能够增强聚丙烯（PP）的阻燃性能,但也会降低其力学性能,因此对阻燃剂进行改性以改善聚丙烯的力学性能显得至关重要。以传统的膨胀型阻燃剂（IFR）[由聚磷酸铵（APP）、季戊四醇（PER）、三聚氰胺（MA）组成]为PP阻燃。在合成APP过程中引入有机蒙脱土（OMt）。APP围绕OMt形成,剥离OMt使其能够较好地分散在阻燃剂中。为使OMt更好地分散在阻燃剂中,在磷酸氢二铵（DAP）、尿素（UREA）溶液中加入OMt,之后对溶液进行超声处理,蒸干后形成DAP-UREA-OMt与五氧化二磷反应生成APP。在PP中添加改性阻燃剂,有助于PP材料阻燃性能的提升与减缓力学性能的下降。当阻燃剂添加量为30%（阻燃剂添加量占总质量的质量分数）时,PP/IFR_APP/OMt复合材料的氧指数达到29.8%,通过V-0测试,拉伸强度为22.0 MPa,高出传统方法0.7 MPa。

Flame retardants could enhance the flame retardancy of polypropylene（PP）,but also reduce its mechanical prop-erties,so it is important to modify the flame retardants in order to improve the mechanical properties of PP.PP flame retardants are mainly the traditional intumescent flame retardants（IFR） including ammonium polyphosphate（APP）,pentaerythritol （PER） and melamine（MA）.Organic montmorillonite（OMt） was introduced in the synthesis of APP.APP formed around OMt,and OMt was stripped to make it dispersed smoothly in flame retardants.Ultrasonic was introduced in the solution of diammonium hydrogen phosphate（DAP）,urea and OMt for better dispersion.Then the compounds（DAP-UREA-OMt） which dried from the solution reacted with P₂O₅ and APP was obtained.Adding modified flame retardants to PP could improve the flame retardancy of PP and slow down the decline of mechanical properties.When 30%（the mass fraction of flame retardant in total mass） flame retardant was added,the oxygen index（LOI） reached 29.8%,and the tensile strength of 22.0 MPa was higherthan that of 0.7 MPa by the traditional method by V-0 test.