聚合物用抗氧剂研究进展

介绍了目前研究最多的4类聚合物用抗氧剂（负载型抗氧剂、高分子量抗氧剂、生物抗氧剂及多功能抗氧剂），详细阐述了4类抗氧剂的结构、合成工艺、抗氧化性能及应用效果，并对聚合物用抗氧剂的未来的发展前景进行了展望。     

抗氧剂

抗氧剂组成物,二氯化磷抗氧剂及聚烯烃树脂组成物,含磷抗氧剂及聚烯烃树脂组成物,芳基亚磷酸酯抗氧剂的制备方法,[编者按]     

我国酚类抗氧剂的现状

至1999年,中国抗氧剂生产企业有30多家,总生产能力17000t,1998年产量约13057.6t,生产的主要产品有酚类、亚磷酸酯类和含硫酯类。本文着重阐述了酚类抗氧剂内容,并对抗氧剂1010、抗氧剂168、抗氧剂1076、抗氧剂259、抗氧剂300、抗氧剂CA及抗氧剂2246的生产企业、生产能力和近两年的生产产量做了详细的介绍。     

受阻酚抗氧剂对挠性覆铜板用胶粘剂老化性能的影响

以双酚A环氧树脂、聚酰胺、双氰胺、阻燃剂为主要原材料,制备了一种改性环氧胶粘剂,并用于制备挠性覆铜板。研究了抗氧剂1010、抗氧剂1098及抗氧剂1010与抗氧剂1098混合物对改性环氧胶粘剂耐热老化、湿热老化性能的影响,并用TG分析了添加不同抗氧剂的改性环氧胶粘剂的耐热稳定性。结果表明,添加抗氧剂1010、抗氧剂1098及抗氧剂1010与抗氧剂1098混合物都可提高胶粘剂体系的热老化、湿热老化后的剥离强度保持率;可提高胶粘剂体系的热分解温度、改善胶粘剂的耐热稳定性,其中抗氧剂1098的效果优于抗氧剂1010,抗氧剂1010与抗氧剂1098混合物的效果优于任何一种单一抗氧剂。在此胶粘剂体系中,抗氧剂1010与抗氧剂1098具有一定的协同抗氧化作用。     

抗氧剂736的制备及其在聚丙烯树脂中的应用

叙述了新型硫代酚类抗氧剂736的制备方法,合成的抗氧剂736收率达到82%以上,产物结构经红外光谱和元素分析确证.采用DSC法测定抗氧剂736及抗氧剂1010在聚丙烯中的抗热氧性能,以氧化诱导期(OIT)为指标评价抗氧剂功效.试验表明:抗氧剂736优于抗氧剂1010.     

抗氧剂YHK-1在ABS树脂中的性能评价

抗氧剂YHK-1由酚类抗氧剂、亚磷酸酯类抗氧剂及特殊添加剂组成。将自制抗氧剂YHK-1与进口同类产品进行比较,发现YHK-1抗氧剂能够更有效地抑制聚合物氧化,完全可替代进口产品而应用于ABS树脂中。     

受阻酚类抗氧剂在高分子领域的研究进展

综述了受阻酚类抗氧剂的种类及其抗氧化作用机理、抗氧化效率的影响因素,并展望了受阻酚类抗氧剂的发展趋势。目前,受阻酚类抗氧剂主要向高稳定性、高抗氧化效率及环境友好的目标发展。提高硫代受阻酚类抗氧剂的相对分子质量及合成反应型硫代受阻酚类抗氧剂将成为研究重点。单酚类抗氧剂与超细粉体接枝将成为重点研究方向。改变抗氧剂骨架结构,简化合成工艺,降低成本,提高与基体的相容性及抗氧化效率将成为多酚类抗氧剂的研究重点。     

抗氧剂LD对NR胶料热氧老化防护的研究

对比研究了抗氧剂LD与抗氧剂264,抗氧剂2246对NR胶料的硫化特性、自由状态下的热氧老化防护性能及耐水抽出性的影响.结果表明,抗氧剂LD对NR胶料硫化特性的影响与抗氧剂2246相近;对NR胶料的热氧老化防护和耐水抽出性接近于抗氧剂2246,而好于抗氧剂264.从性能价格比来说,抗氧剂LD具有很好的应用价值.在NR胶料中抗氧剂LD用量以1～2份为宜.     

抗氧剂对PMMA树脂的热稳定作用

采用连续本体法合成了纯聚甲基丙烯酸甲酯（PMMA）树脂,将不同种类的抗氧剂与PMMA树脂进行熔融共混,在空气气氛中采用热失重法测试了PMMA树脂的热稳定性。考察了抗氧剂种类、用量及复配比例等因素对PMMA树脂热稳定性的影响。实验结果表明,分别加入抗氧剂1076、抗氧剂2246、抗氧剂245和抗氧剂1010等主抗氧剂可以显著提高PMMA树脂的热稳定性,辅助抗氧剂（抗氧剂168）可以提高PMMA树脂的起始热分解温度,改变抗氧剂1010与抗氧剂168的复配比例时,抗氧剂1010用量越多,PMMA树脂的热稳定性越好。抗氧剂总量为2.5 ‰（质量分数,下同）,抗氧剂1010与抗氧剂168的比例为3：1时,PMMA树脂的热稳定性显著提高。     

不同复配抗氧剂体系对聚碳酸酯性能的影响

利用热失重分析、差式扫描量热仪分析等手段研究了三种不同分子结构亚磷酸酯类抗氧剂对聚碳酸酯(PC)加工稳定性的影响,并研究了抗氧剂添加量对PC力学性能、热稳定性、熔体质量流动速率的影响。测试结果表明,添加抗氧剂能够提高PC的初始热分解温度及玻璃化转变温度;三种抗氧剂效果的排序为抗氧剂B抗氧剂A抗氧剂168,在潮湿环境下,抗氧剂效果排序为抗氧剂168抗氧剂B抗氧剂A。     

聚合物抗氧剂结构与抗氧性能关系

介绍了胺类、酚类、亚磷酸酯类、硫类及天然抗氧剂的结构与抗氧性能的关系,及各个官能团在抗氧剂中的作用,并展望了国内外抗氧剂的发展。     

抗氧剂在塑料中的应用

以实例说明了天然抗氧剂、反应型抗氧剂、非酚类抗氧剂等几种抗氧剂在塑料中的应用,并提出应注重抗氧剂的应用研究.     

Are natural antioxidants better – and safer – than synthetic antioxidants?

Antioxidants are necessary in the Western diet as it is rich in polyenoic fatty acids, which are easily oxidized with formation of free radicals that are harmful if present in higher amounts. Consumers prefer natural antioxidants to synthetic antioxidants, mainly for emotional reasons. The common Western daily diet contains about 1 g natural antioxidants even if no natural antioxidants have been added for lipid stabilization. Their main sources are cereals, fruits, vegetables, and beverages. Only a part of the natural antioxidants is absorbed and used as free‐radical scavengers in vivo. Natural antioxidants should be added to food in larger amounts than synthetic antioxidants as they are less active, but the actual activity depends very much on particular conditions and food composition. Nevertheless, the addition of additional antioxidants is still negligible in comparison with the dietary supply of native antioxidants. The safety limits of natural antioxidants are mostly not known, but they are hardly safer than synthetic antioxidants. The best protection would be to replace high‐polyenoic oils in the diet with high‐oleic oils, and to use alternative methods of food protection against autoxidation.     

耐热抗氧化尼龙6切片的制备与性能研究

通过聚合前添加抗氧化剂制备了耐热抗氧化尼龙6切片,研究不同配方抗氧剂对抗氧化性能的影响,其中酚类抗氧剂会在萃取过程中变色,在耐萃取变色方面非对称结构的酚类抗氧剂要好于对称结构的酚类抗氧剂,而通过与抗水解性好的亚磷酸酯抗氧剂复配可得到正常颜色的尼龙6切片,能有效防止高温黄变及力学性能下降,并在后加工时黏度稳定。     

受阻胺类橡胶防老剂研究进展及发展趋势

从橡胶的老化机理出发介绍受阻胺类橡胶防老剂的防老化作用机理,以合成受阻胺类橡胶防老剂基础原料(萘胺和萘酚、苯胺、对取代基苯胺、二苯胺、对苯二胺、对氨基二苯胺)的不同把防老剂分为六类,详细介绍了一些代表性防老剂,并在此基础上总结出以各原料为基础合成防老剂的常用路线。最后指出受阻胺类橡胶防老剂的发展趋势。     

橡胶防老剂合成技术进展

我国是全球橡胶防老剂主要生产国和消费国，但是落后的工艺技术和日趋严格的环境保护法出台给我国橡胶防老剂业发展带来较大压力，开发新型工艺及清洁工艺成为我国橡胶防老剂未来发展重点。本文介绍了国内主要的橡胶防老剂如防老剂4020、40201NA、RD、3100、MMB、FAO-7和烃化聚酚等合成技术进展。     

不同防老剂并用种类对EPDM共混胶耐老化性能的影响

研究了不同防老剂并用种类对EPDM共混胶耐老化性能的影响,研究表明,防老剂并用种类对共混胶的硫化程度有一定的影响,对焦烧时间、工艺正硫化时间影响不大;老化后,拉伸强度变化率较好的是防老剂445/NBC和防老剂2246/445,扯断伸长率较高的是防老剂445/DDA和防老剂2246/MB,综合性能来看,防老剂2246/MB和防老剂445/DDA两者并用效果较好。     

A review on losses and transformation mechanisms of common antioxidants

Antioxidants are considered to be one of the most effective ways to prevent and delay the rancidity of oils and fats, thus play an important role in the processing, packaging, and storage of oils, fats, and oleaginous foods. However, the losses of antioxidants inevitably occur while preventing the rancidity of oils and fats. In this work, the loss pathways and mechanisms of synthetic and natural antioxidants commonly used in oils, fats, and oleaginous foods systems during storage, use, and detection are critically reviewed. The discussion regarding the transformation of antioxidants or antioxidant models in various organic solvent systems is also covered as well as the fate, toxicities, and antioxidative activities of transformation products of antioxidants. At room temperature, antioxidants in oils and fats are mainly lost due to antioxidation with transformation products accumulated. Under thermal (heating and frying) condition, synthetic antioxidants are mainly lost due to volatilization, while natural antioxidants are mainly lost due to transformation. Under frying condition, adsorption also contributes to the losses of antioxidants. This review discusses some possible research directions regarding antioxidants applied in oils, fats and oleaginous foods, which is expected to benefit the use of antioxidants in food industry.     

Synthesis and antioxidant activities in polyolefin of dendritic antioxidants with hindered phenolic groups and tertiary amine

Two novel primary antioxidants with dendritic structure and hindered phenolic groups were synthesized using 3‐(3,5‐diter‐butyl‐4‐hydroxyphenyl) propionic acid as raw material and dendritic poly(amidoamine) (PAMAM) as linker in chloroform. The antioxidant activities of the dendritic antioxidants were evaluated in polyolefin by melt flow index (MFI), yellowness index (Y.I.), and oxidation induction time (OIT). The dendritic antioxidants had excellent processing property and oxidation resistance behavior in polyolefin. At the same weighed amount of antioxidant, the MFI and Y.I. values of mulitiple‐extruded polyethylene (PE) stabilized with the dendritic antioxidants were smaller than those of the commercial antioxidants, as well as the OIT values of polyethylene (PE) stabilized with the dendritic antioxidants were larger. Applying to polypropylene, the antioxidant ability of the second‐generation dendritic antioxidant (G2.0 dendritic antioxidant) with larger molecular weight was superior to the commercial antioxidants and that of the first‐generation dendritic antioxidant (G1.0 dendritic antioxidant) was equal to the commercial antioxidants. The dendritic antioxidants can prevent polyolefin from breaking of macromolecular chain in processing and had stabilizing effect in polyolefin in service life by donating H‐atoms and electron to free radicals. The dendritic antioxidants combined with Irgafos 168 had improvement of antioxidant activities of the dendritic antioxidants in polyolefin. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012