不同配比的水-乙醇中密胺树脂包覆聚磷酸铵及其阻燃性能

采用原位聚合法制备密胺树脂包覆聚磷酸铵（MFAPP），研究了不同体积比的水-乙醇混合溶剂对包覆效果的影响，并考察不同包覆产物对聚丙烯（PP）阻燃性能的影响。采用溶解度实验、红外光谱（FT-IR）、热重分析（TG）、扫描电镜（SEM）分别考察聚磷酸铵（APP）包覆前后溶解度、官能团、热稳定性以及表面形态的变化；通过氧指数、耐水性实验考察了APP包覆前后对PP阻燃性能的影响。实验结果表明：与APP相比，以水-乙醇为混合溶剂制备的MFAPP，其耐水性得到明显改善，在水中的溶解度明显下降；红外结果显示MFAPP中产生了三聚氰胺新的官能团。随着溶剂中水的比例增加，MFAPP中壳材密胺树脂含量增加，水和乙醇体积比约为1：1时，APP包覆效果最好，耐水性提高最大。PP中MFAPP的w=30%时，复合材料阻燃性能最佳，氧指数达到29.5%。

Microencapsulation of Ammonium Polyphosphate in Different Volume Ratios of Water and Alcohol and Its Flame Retardance in Polypropylene

Melamine-formaldehyde resin microencapsulated with ammonium polyphosphate (MFAPP) was prepared by in situ polymerization.The influence of volume ratios of water and alcohol on the encapsulation of APP and the effect of MFAPP on the flame retardance in PP were investigated.The MFAPP was characterized by solubility measurement,FT-IR,TG,SEM.The effect of microencapsulation on the flame retardance in PP was studied by measuring the limiting oxygen index and water resistance.Compared with APP,the solubility of MFAPP prepared in water-alcohol mixed solvent decreased sharply,and the appearance of melamine function group was observed through FT-IR analysis.With the increase of the ratio of water and ethanol,the content of melamine-formaldehyde resin in MFAPP increased.When the volume ratio of water and alcohol is about 1:1,the microencapsulation and water resistance of MFAPP were the best.With w=30% MFAPP in PP,the LOI value of PP/MFAPP was as high as 29.5%.