Taguchi Yoshihiko, Ishida Yasuyuki, Ohtani Hajime, Bekku Hiroyuki, Sera Masaya
Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.
Anal Sci. 2004 Mar;20(3):495-9. doi: 10.2116/analsci.20.495.
A polymeric hindered amine light stabilizer (HALS), Tinuvin 622 (MW [symbol: see text] 4000), in PP materials formulated with a magnesium hydroxide flame retardant was determined by reactive thermal desorption (RTD) gas chromatography (GC). Two kinds of the HALS components that were formed through the RTD in the presence of tetramethylammonium hydroxide [(CH3)4NOH, TMAH] were clearly observed in the chromatograms of the PP samples, with negligible interference from the other additives and the PP substrate. Here, the coexisting flame retardant was proved to affect significantly the RTD process of the occluded HALS. As a result, the recovery of the HALS components in the RTD-GC chromatograms of the PP samples increased with increase in the content of the flame retardant. This enhancement of the HALS recovery is attributed mainly to the preferential exposure of the HALS on the surface of the ground PP sample through the interaction between the polymeric HALS and the flame retardant in the molten PP during kneading. In spite of such a considerable action of the flame retardant, the observed intensities of the characteristic peaks of HALS by RTD-GC showed a good linear relationship with the HALS content in the PP samples with constant content of the flame retardant (50 phr); this relationship could be used as the calibration line for the determination of the polymeric HALS in the PP materials containing the flame retardant.
采用反应热脱附（RTD）气相色谱法（GC）测定了在含有氢氧化镁阻燃剂的聚丙烯（PP）材料中的一种聚合型受阻胺光稳定剂（HALS）——Tinuvin 622（分子量约4000）。在PP样品的色谱图中清晰观察到了两种在氢氧化四甲铵[（CH3）4NOH，TMAH]存在下通过RTD形成的HALS组分，其他添加剂和PP基体的干扰可忽略不计。在此，证明共存的阻燃剂对被包裹的HALS的RTD过程有显著影响。结果，PP样品的RTD-GC色谱图中HALS组分的回收率随阻燃剂含量的增加而提高。HALS回收率的这种提高主要归因于在捏合过程中，聚合型HALS与熔融PP中的阻燃剂之间的相互作用，使得HALS优先暴露在研磨后的PP样品表面。尽管阻燃剂有如此显著的作用，但在阻燃剂含量恒定（50 phr）的PP样品中，通过RTD-GC观察到的HALS特征峰强度与HALS含量呈现良好的线性关系；这种关系可作为测定含阻燃剂PP材料中聚合型HALS的校准曲线。
