A series of model linear copolymers of 2-hydroxyethyl methacrylate (HEMA) and a sterically hindered amine derivative [N-(2,2,6,6-tetramethyl-piperidin-4-yl)methacrylamide (HAS)] were synthesized and characterized. Scavenging activities of the copolymers against reactive oxygen species (peroxyl and hydroxyl radicals) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals were determined. It was found that copolymers with medium HAS content (3.5–4.0 mol %) were better scavengers than copolymers with lower and higher HAS content and also than polyHEMA and polyHAS homopolymers and the HAS monomer. Importantly, these copolymers compared favorably even to established low-molecular weight antioxidant standards (BHA and dexpanthenol). Monomer reactivity ratios were determined, and the microstructure of the copolymers was assessed. Subsequently, cross-linked copolymers in the powder and film forms with optimal HAS content were synthesized. Their scavenging activities against the three types of radicals were determined, revealing that these hydrogels are potent scavengers of reactive oxygen species.
                                    合成并表征了一系列 2-羟乙基
甲基丙烯酸酯(
HEMA)和立体受阻胺衍
生物[N-(2,2,6,6-四甲基-4-
哌啶基)甲基
丙烯酰胺(HAS)]的线性共聚物模型。测定了共聚物对活性氧(过氧自由基和羟基自由基)和 2,2
-二苯基-1-苦基
肼(
DPPH)自由基的清除活性。结果发现,中等 HAS 含量(3.5-4.0 摩尔 %)的共聚物比 HAS 含量较低和较高的共聚物,以及聚 
HEMA 和聚 HAS 均聚物和 HAS 单体具有更好的清除效果。重要的是,这些共聚物甚至可与既定的低分子量
抗氧化剂标准(
BHA 和去
泛醇)进行比较。测定了单体反应比,并评估了共聚物的微观结构。随后,合成了具有最佳 HAS 含量的粉末和薄膜形式的交联共聚物。测定了它们对三种自由基的清除活性,结果表明这些
水凝胶是有效的活性氧清除剂。