在各种聚合物的降解过程中,布米特里类型紫外线光吸收器的残留行为上的差异
Hisayuki Nakatani1,2, Taishi Uchiyama1, Suguru Motokucho1,2
1Polymeri Materials Laboratory, Chemistry and Materials Engineering Program, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan.
Polymers
|January 26, 2024
概括
这项研究研究了各种聚合物在增强降解过程中的紫外线吸收器 (UVA) 损失. 从聚合物基质的漏,而不是化学变化,被确定为UVA损失的主要原因.
科学领域:
- 聚合物科学 聚合物科学
- 环境化学环境化学
- 材料降解 材料降解
背景情况:
- 聚合物被广泛使用,但容易降解.
- 紫外线吸光剂 (UVAs) 添加到聚合物中,以防止光降解.
- 了解紫外线损失机制对于预测聚合物寿命至关重要.
研究的目的:
- 使用增强降解方法 (EDM) 研究紫外线吸光器 (UV-326) 在各种聚合物 (PP,HDPE,LDPE,PLA,PS) 中的降解.
- 确定聚合物降解过程中UVA损失的主要机制.
主要方法:
- 使用海水中的硫酸盐离子激素的增强降解方法 (EDM) 进行均的聚合物降解.
- 在含有UV-326.6的不同聚合物矩阵 (PP,HDPE,LDPE,PLA,PS) 中分析的UVA损失率.
- 在降解过程中表征聚合物表面变化和UVA化学结构.
主要成果:
- 像PP和PS这样的聚合物在UVA存在时显示出快速变白和物理降解.
- 由于其更高的玻璃过渡温度 (Tg),PS中的UVA损失率较慢.
- 在大多数聚合物中,微塑性显著增加了最初的UVA损失率,但液是主要的损失机制,而不是UVA的化学变化.
结论:
- 在增强降解过程中,聚合物中紫外线吸收器 (UVA) 损失的主要机制是漏.
- 聚合物的特性,如玻璃过渡温度,会影响UVA损失的速度.
- 在整个降解过程中,UVA (UV-326) 的化学结构保持稳定.
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