使用高温尺寸排除色谱与三重检测精确估计聚烯混合物的摩尔质量:深入了解聚烯的分子水平混合与聚乙烯的各种应用等级
Yogesha Subbaiah1, Ahmad Salem AlAhmadi1, Mark Debasagoiti1
1R & D Laboratory, TASNEE Technology and Innovation Centre, Al-Jubail Industrial City, Saudi Arabia.
Journal of separation science
|January 14, 2025
概括
这项研究优化了使用先进探测器的尺寸排除色谱 (SEC) 进行聚合物混合分析. 先进的SEC方法在分子层面上准确地确定聚烯/聚乙烯混合物组成.
科学领域:
- 聚合物科学与工程 聚合物科学与工程
- 材料的特性 材料的特性
- 类风病学 类风病学 类风病学
背景情况:
- 对聚合物混合物的准确表征对于预测和控制材料特性至关重要.
- 分析聚烯 (PP) 和聚乙烯 (PE) 混合物的传统方法的精度可能受到限制.
- 了解分子级混合是优化混合性能的关键.
研究的目的:
- 评估高级尺寸排除色谱 (SEC) 检测模式的有效性,用于分析PP/PE混合物.
- 评估聚烯同聚合物 (H-PP) 和吹塑聚乙烯 (PE) 混合物的分子水平混合.
- 为了比较粘度计 (VISCO) 和多角度激光光散射 (MALS) 探测器的精度,与SEC中常规的红外-5 (IR-5) 检测相比.
主要方法:
- 化混合H-PP与PE以制造聚合物混合物.
- 使用IR-5,VISCO和MALS探测器进行高温尺寸排除色谱 (SEC) 分析.
- 通过SEC.确定分子量 (MW) 和MW分布.
- 使用13C核磁共振进行混合成分分析.
- 通过比较理论和测量的重量平均MW (Mw) 来评估分子水平的混合.
主要成果:
- 与IR-5检测相比,VISCO和MALS探测器与预测的混合比率更接近.
- 对VISCO和MALS的百分比误差分别在4.53~5.99和1.57~7.65之间.
- 观察到融化流速 (MFR) 和Mw之间的线性关系,表明有效的分子水平混合.
结论:
- 先进的SEC检测模式 (VISCO,MALS) 可以更准确地量化PP/PE混合物成分.
- 该方法证实了准备好的H-PP/PE混合物中有效的分子水平混合.
- 在分析与H-PP混合的各种PE等级时,SEC方法得到了验证.
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