氢氧化镁的表面改性及其复合阻燃尼龙6分析分析.docx

硕士论文 氢氧化镁的表面改性及其复合阻燃尼龙6研究
摘要 l掣Ull2ll 15II 2I 111II 1IIl3I哕
本文制备了分散性高的改性氢氧化镁(MH)阻燃剂,并将其与三聚氰胺氰尿酸盐(MCA)共混入尼龙6材料中,研究复合材料的阻燃、力学、耐热性能及阻燃机理。
首先,以硫酸镁、氨水为原料,硬脂酸/硬脂酸钙(SA/CaSt)为改性剂,合成SA/CaSt 改性MH。通过比较不同配比改性MH的润湿程度以及沉降速度确定改性剂的最优配比为l:2。通过FTIR、XRD、SEM等手段对最优配比改性MH进行表征,结果表明:SA/CaSt
的复配能阻止长链的缠结,促使MH表面有机包覆完全,极性减小,结晶也更加规则。其次,选取SA/CaSt改性MH与MCA作为复配阻燃剂,通过挤出、注塑制备复合
阻燃尼龙6。通过对不同配比复合阻燃尼龙6的阻燃、耐热、机械性能进行对比发现: 当两阻燃剂质量比为1:1时,力学性能达到最优,同时阻燃剂发生协同作用,促使尼龙 6的燃烧机理由解聚分解转化为直接炭化分解,有效抑制滴落,综合阻燃性能大大提高。
最后,以Zr801为改性剂进一步对MH进行表面改性,合成改性花球状MH阻燃剂, 通过活化指数、润湿程度、FTIR、XRD、SEM、TG等手段进行表征,结果表明:ZrS01 的改性促使MH片层发生重组,结晶更加有序,同时呈现超高的分散性。再将锆改性花球状MH与MCA复配共混入尼龙6材料中,测试复合材料的阻燃、耐热、机械性能, 结果表明:锆改性MH与MCA发挥协同作用,有效控制熔滴,增强复合材料的阻燃、力学以及耐热性能。通过对燃烧产物的进一步研究发现其协同阻燃机理为锆原子外n=4 电子层可以吸收外界电子,促进碳正离子的形成。
关键词:SA/CaSt改性MH,MCA,锆改性花球状MH,复合阻燃,阻燃机理
Abstract
A novel modified magnesium hydroxide(MH)flame retardants were essfullv prepared In this and melamine cyanurate(MCA)were mixed with polyamide 6, alld the fire—retardant properties,mechanical properties,heat performance and the flarne retardant mechanism were studied.
Firstly,SA/CaSt。modified MH particles were synthesized by surface modification with SA/CaSt plex surface optimum ratio of SA/CaSt was 1:2,which lrmed by water contact angle and sedimentation volume modification results were evaluated by FTIR,XRD and SEM,then SA/ MH/PA6 was also results indicated that plex modified samples exhibited
good dispersion and crystal lattice.
Secondly,the flame。retarded PA6 was prepared by extruder and injection molding machine using SA/CaSt。modified MH and MCA as flame e虢ct of the mixture
on physical property,heat。resistant quality,flame retardance Was experimentally
investigated.
The results showed that the obtained physical property was the best when the ratio of SA/CaSt‘modified MI-UMCA was I:1,while the synergetic effect of flame retardants could decrease the buming posites,and the drippings in flames.
Thirdly,the f