含硫烷基酚类精细化学品的合成方法及应用

介绍了含硫烷基酚类精细化学品的合成方法和应用,包括由烷基酚与一氯化硫、二氯化硫反应形成的硫代酚类产品(如抗氧剂300、硫化剂Vultac2等)。还介绍了由烷基酚与甲醛、硫醇缩合反应形成产品(如抗氧剂1520、甲叉-4426-S等)的合成方法和应用情况。     

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.     

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。     

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。     

硫酯类抗氧剂的合成与应用

介绍了国内外硫酯类抗氧剂各种生产工艺路线及应用技术，阐述了国内外抗氧荆产品结构的差异，提出了我国硫代酯类抗氧剂的发展建议。     

高分子量酚类抗氧剂

本文综述了抗氧剂的一般情况和制备高分子量酚类抗氧剂的基本原理,介绍了作者研制的聚合型高分子量抗氧剂,这些抗氧剂用于高密度聚乙烯树脂,其抗热氧性能大大优于国内现有的抗氧剂品种。     

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。     

受阻酚类抗氧剂的研究进展

综述了受阻酚类抗氧剂的研究概况、分类、作用机理、抗氧剂效率的影响因素和着色机理,介绍了几种受阻酚类抗氧剂的典型产品,并预测了受阻酚类抗氧剂的发展趋势。     

非对称受阻酚类抗氧剂及其应用

非对称受阻酚类抗氧剂是当今世界聚合物抗氧剂研究领域的一大趋势,介绍了非对称受阻酚类抗氧剂的结构、性能及其代表性品种,同时指出了该类抗氧剂的应用前景,对生产加工有一定的参考价值。     

受阻酚类抗氧剂的研究现状及发展趋势

介绍了受阻酚类抗氧剂的结构特点、抗氧化机理以及几种典型产品,并提出了受阻酚类抗氧剂的发展趋势.     

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。     

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。     

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.     

聚合物抗氧剂技术进展

抗氧剂是重要的聚合物稳定化助剂，文章全面而系统地综述了聚合物抗氧剂工业的理论研究进展和技术开发趋势，进而归纳了近十年来国内外抗氧剂品种的主要结构和应用特征，旨在推动国内抗氧剂工业的技术进步。     

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。     

品红甲亚胺染料影像光稳定性的研究——抗氧化剂和单重态氧的反应能力及其对染料影像光褪色的影响

本文研究了苯酚类(A),双酚类(B),对苯二酚类(C),色满类(D)和双螺色满类(E)抗氧化剂的性能。通过循环伏安法测定了它们的氧化电位;用类似Stern-Volmer关系图求得各抗氧化剂和单重态氧的反应速率常数。抗氧化剂的氧化电位越小,和单重态氧的反应速率常数越大,对品红甲亚胺染料影像的防褪色效果越好,进一步证实了染料褪色的光氧化反应机理。在这些抗氧化剂中,它们的防褪色效果依次为D>E>C>B>A。     

New oligomer‐bound antioxidants in natural rubber/polybutadiene rubber and natural rubber/styrene–butadiene rubber blends

New paraphenylene diamine antioxidants were prepared. The efficiency and permanence of these oligomer‐bound paraphenylene diamines were compared with those of conventional amine‐type antioxidants in elastomer blends such as natural rubber/styrene–butadiene rubber and natural rubber/polybutadiene rubber. These oligomer‐bound antioxidants showed improved aging resistance and ozone resistance in comparison with the blends containing conventional antioxidants. The liquid oligomer‐bound paraphenylene diamine could replace the plasticizer required for compounding. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 437–443, 2004     

Stabilisation of edible oils with natural antioxidants

Natural antioxidants have recently gained increased interest because of the belief that natural food ingredients are better and safer than synthetic ones. The review presents the results on stabilisation of the main edible oils with different types of natural antioxidants. Sources of natural antioxidants are spices, herbs, teas, oils, seeds, cereals, cocoa shell, grains, fruits, vegetables, enzymes, proteins. Researchers concentrate on ascorbic acid, tocopherols and carotenoids as well as on plant extracts containing various individual antioxidants such as flavonoids (quercetin, kaemferol, myricetin), catechins or phenols (carnosol, rosmanol, rosamaridiphenol) and phenolic acids (carnosic acid, rosmarinic acid). Ascorbyl palmitate is regarded as a 'natural' antioxidant because it is hydrolysed in the body to ascorbic and palmitic acids. Among the herbs of the Lamiaceae family, rosemary has been more extensively studied and its extracts are the first marketed natural antioxidants. Oregano, which belongs to the same family, has gained the interest of many research groups as a potent antioxidant in lipid systems. The review concerns the following main topics: stabilisation of oil with individual natural antioxidants, interaction of antioxidants with synergists, stabilisation of oil with extracts or dry materials from different plant sources (e.g. herbs and spices), stabilisation at frying temperatures and in emulsions.