有机硅改性环糊精在膨胀阻燃聚丙烯中协同作用的研究

Synergistic Effect of Organic Silicon Modified β-cyclodextrin in Intumescent Flame Retarded Polypropylene

以1,1,3,3-四甲基二硅氧烷、烯丙基缩水甘油醚、β-环糊精(β-CD)为原料合成了一种新型有机硅改性环糊精(CDS)。红外光谱测试表明,β-CD接枝到硅氢加成反应制得的聚合物链端。利用热重分析、氧指数测试、垂直燃烧、扫描电镜分析等手段对比探讨聚丙烯(PP)/膨胀阻燃剂(IFR)/β-CD和PP/IFR/CDS复合材料热失重行为、阻燃性能、微观结构及力学性能。结果表明,IFR/CDS具有良好的协同阻燃作用,同时提高了材料的力学性能。当CDS含量为1.5%(质量分数,下同)时,PP/IFR/CDS复合材料的极限氧指数为35.0%,垂直燃烧通过UL94V-0测试,拉伸强度、弯曲强度和冲击强度分别比PP/IFR/β-CD复合材料提高了8.6%、16.8%和70.7%。

A polysiloxane modified β-cyclodextrin （CDS） was synthesized from tetramethyl dihydro disiloxane, allyl glycidyl ether, and β-cyclodextrin （β-CD）. FTIR showed that β-CD was grafted to the chain ends of polysiloxane. The prepared CDS was employed in a flame retarding polypropylene system containing also an intumescent flame retardant （IFR）, and compared with unmodified β-CD in the thermal and mechanical properties using thermogravimetric analysis （TGA）, limiting oxygen index （LOI）, scanning electron microscopy （SEM）, etc. It showed that CDS had a synergistic effect with IFR, which promoted the formation of stable, continuous and compact char structure at high temperature. When the content of CDS was 1.5 wt%, the LOI of the system was 35.0 %, and it passed the UL94 V-0 test. The tensile, flexural, and impact strength were 8.6 % ,16.8 % and 70.7 % higher, respectively, than those based on β-CD.