期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
三氟甲烷磺酸稀土盐对聚丙烯热稳定性的影响及机理
1
作者 冉诗雅 沈海峰 +3 位作者 李晓楠 王子路 郭正虹 方征平 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2019年第6期1333-1340,共8页
通过熔融共混将三氟甲烷磺酸镱[Yb(OTf) 3]和三氟甲烷磺酸镧[La(OTf)3]添加至聚丙烯(PP)中,制得PP/Yb和PP/La材料,并对其热稳定性进行表征.热失重分析(TGA)和差示扫描量热分析(DSC)结果显示, Yb(OTf) 3和La(OTf) 3均可以显著提高聚丙烯... 通过熔融共混将三氟甲烷磺酸镱[Yb(OTf) 3]和三氟甲烷磺酸镧[La(OTf)3]添加至聚丙烯(PP)中,制得PP/Yb和PP/La材料,并对其热稳定性进行表征.热失重分析(TGA)和差示扫描量热分析(DSC)结果显示, Yb(OTf) 3和La(OTf) 3均可以显著提高聚丙烯的热稳定性.当Yb(OTf) 3添加量仅为1%(质量分数)时, PP的起始分解温度从275 ℃提高至305 ℃,最大分解温度从384 ℃提高至405 ℃, 160 ℃下的氧化诱导时间从12.1 min延长至43.0 min,热焓从1907 J/g降低至483 J/g;而PP/La1的起始分解温度、最大分解温度、 160 ℃下的氧化诱导时间和热焓分别为300 ℃, 409 ℃, 18.6 min和633 J/g.结果表明, La(OTf) 3对聚丙烯热稳定性的改善作用弱于Yb(OTf) 3,对2种稀土盐产生不同实验结果的原因进行分析并提出机制.由于阴离子和阳离子的共同作用, Yb(OTf) 3和La(OTf) 3均可提高PP的热氧稳定性. La(OTf) 3中三氟甲烷磺酸根的自由基捕捉能力和稀土离子的配位能力发挥主要作用,而Yb(OTf) 3中的稀土离子的高反应活性也起到关键作用. 展开更多
关键词 三氟甲烷磺酸稀土盐 自由基捕获 聚丙烯热稳定性
下载PDF
One-step synthesis of hydrophobic magnesium hydroxide nanoparticles and their application in flame-retardant polypropylene composites 被引量:10
2
作者 Hongyan Shen Youzhi Liu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第10期2199-2205,共7页
Hydrophobic magnesium hydroxide(MH) nanoparticles were prepared by a one-step synthesis method in a high-gravity environment generated by a novel impinging stream–rotating packed bed(IS-RPB) reactor. The reactant sol... Hydrophobic magnesium hydroxide(MH) nanoparticles were prepared by a one-step synthesis method in a high-gravity environment generated by a novel impinging stream–rotating packed bed(IS-RPB) reactor. The reactant solutions were simultaneously and continuously pumped into the IS-RPB reactor, and then Tween80 was added as a surface modifier. The morphology, structure, and properties of blank and hydrophobic MH were characterized. The effects of MH nanoparticles on the flame retardancy, thermal stability, and mechanical properties of PP/MH composites were also studied. We found that the obtained MH nanoparticles exhibited hexagonal lamella with a mean size of 30 nm, excellent hydrophobic properties(e.g., high water contact angle of 112°), and improved thermal stability of MH. The limiting oxygen index(LOI) further showed that increased MH loading can significantly improve flame-retardant performance, which reached 29.3% for PP/MH composites with 30 wt% hydrophobic samples. The thermal stability and mechanical properties of the PP/MH composites with hydrophobic samples were also much higher than those of PP/MH composites with blank MH. Results showed that the one-step synthesis had high potential application in the large-scale production of hydrophobic MH nanoparticles. 展开更多
关键词 Magnesium hydroxide SYNTHESIS POLYPROPYLENE Hydrophobic property Rotating packed bed
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部