新型防老剂2246通过技术鉴定

上海向阳化工厂研制成功的新型防老剂2246最近由上海化学原料工业公司主持通过技术鉴定。防老剂2246[2,2′-亚甲基-双(4-甲基-6-特丁基苯酚)]是烷基多酚类防老剂,属于通用型强力酚类非污染性防老剂。它对合成橡胶,天然橡胶均有较佳的抗龟裂能力和抗老化作用,在水中分散性能好,不污染,不变     

新型防老剂2246通过技术鉴定

上海向阳化工厂研制成功的新型防老剂2246最近由上海化学原料工业公司主持通过技术鉴定。防老剂 2246[2,2′-亚甲基-双(4-甲基-6-特丁基苯酚)]是烷基多酚类防老剂,属于通用型强力酚类非污染性防老剂。它对合成橡胶、天然橡胶均有较佳的抗龟裂能力和抗老化作用,在水中分散性能好,不污染,不变色,其分散体是优良的胶乳防老剂。在白色及艳色橡胶制品中应用,可达到不变色、不污染的效果。     

合成橡胶防老剂的新进展

防老剂是合成橡胶在合成与加工中用量最多的助剂之一。近年来,为了使防老剂具有高效、持效、不污染和低毒性等特点,橡胶助剂行业很注意新型抗臭氧剂及酚类、反应型防老剂的开发研究。     

专利介绍

<正>纳米氧化锌改性氯丁橡胶喷涂型胶粘剂由TA-85氯丁橡胶、纳米氧化锌、氧化镁、氧化镁CN101260281(2008-09-10)。该胶粘剂配方150#、防老剂BHT、硅酸钙、液态树脂、FRJ-551烷基     

液体复合防老剂XD-1680在顺丁橡胶中的应用

将以硫酚化合物与酚类抗氧剂及碳离子基捕获剂配合制成的复合液体防老剂XD-1680用于镍系顺丁橡胶中,以提高产品的防老化性能。对制备的分别添加有防老剂XD-1680、防老剂BHT、复合防老剂XD-1580和2088-1076的顺丁橡胶试样进行了热氧老化试验,测试了它们外观颜色和门尼黏度的变化、氧化诱导期和氧化诱导温度、高温剪切性能以及硫化特性,分析了各防老剂的热稳定性能。结果表明,采用防老剂XD-1680时顺丁橡胶产品表现出良好的门尼黏度稳定性和抗黄变性能,其综合防老化性能优于目前工业化生产装置上所使用的其他几种对比防老剂。     

硫酚防老剂产物的制备方法及在合成橡胶中应用

<正>本发明硫酚防老剂产物的制备方法及在合成橡胶中应用,属于化工产品生产及高分子材料应用技术领域。硫酚防老剂产物为含有2,4-二(甲撑-S-乙酸异辛酯)-6-甲基苯酚和2-(甲撑-S-乙酸异辛酯)-6-甲基苯和4-(甲撑-S-乙酸异辛酯)-6-甲基苯酚,与终止剂、与液体酚类抗氧剂配合,制成一种常温下处于液体形态的复合防老剂;采用水乳液生产工艺,将复合防老剂与非离子表面活性剂、与分散剂强力剪切混合,制成复合防老剂乳液产品。用于乳液     

橡胶防老剂2-巯基甲基苯并咪唑的合成

以甲基邻苯二胺、二硫化碳为原料合成橡胶防老剂2-巯基甲基苯并咪唑。     

锦江油化厂增建500t/a“BHT”生产线

由于国内防老剂 BHT(2,6-二叔丁基对甲酚,国内商品名称为防老剂264,石油添加剂 T-501)市场供不应求,锦江油化厂根据本厂的原料(自产异丁烯)优势决定在正建设的叔丁基苯酚装置内,增建一条500t/a 防老剂 BHT 生产线。现在正和叔丁基苯酚装置同步建设,计划在今年第四季度同时建成投产。     

毛细管法测定防老剂D与BHT的熔点

为了准确测定防老剂D与BHT的熔点,用两端开口毛细管法、一端开口毛细管法和数字熔点仪测定了两种防老剂的熔点。结果表明,两端开口毛细管法测得的数据精密度较高,而且此法方便、经济。总结了两端开口毛细管法测定防老剂D与BHT的影响因素及注意事项。     

丁腈橡胶热氧老化与防护的研究进展及反应机理探讨

综述了国内外丁腈橡胶(NBR)热氧老化及防护的研究进展,探讨了NBR热氧老化及2种防护类型的化学反应机理。NBR生胶热氧老化后使得分子链断裂生成带有醛、酮等基团的聚合物,并产生HCN、NH_3等小分子化合物。胺类是抗热氧老化最佳的链终止型防老剂,酚类、烷基苯基亚磷酸酯类和硫酯类化合物的单一组分或复合体系是破坏氢化过氧化物型防老剂,硫酯类防老剂具有高效的抗热氧老化效果。     

Relationship between bridged groups and antioxidant activity for aliphatic diamine bridged hindered phenol in polyolefins

Four aliphatic diamine bridged hindered phenols were successfully synthesized with aliphatic diamine as the bridged group and 3‐(3,5‐di‐tert‐butyl‐4‐hydroxy‐phenyl)‐propionyl chloride as the material, and their structures were clarified by NMR, Fourier transform infrared spectroscopy, and mass spectrometry. Their performance as antioxidant for polypropylene (PP) and linear low‐density polyethylene (LLDPE) were investigated through the melt flow rate and the oxidation induction time. The thermooxidative stabilities of PP and LLDPE with different aliphatic diamine bridged hindered phenols were assessed by the measurement of the oxidation induction temperature and with long‐term aging testing. The results showed that aliphatic diamine bridged hindered phenols could protect two kinds of polyolefins from thermal oxidative degradation, and the mechanical properties and antioxidant activities of polyolefins stabilized with aliphatic diamine bridged hindered phenols were increased with increasing length of the bridged group for aliphatic diamine bridged hindered phenols at the same concentration of phenolic hydroxyl group. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45095.     

A New Antioxidant Active Film Based on HDPE and Peppermint Essential Oil for Packaging Soybean Oil

In this research, the effect of antioxidant active package was studied on oxidative stability of soybean oil at 40 °C during 2‐month storage. A synthetic antioxidant [Butylatedhydroxytoluene (BHT), 200 ppm] and peppermint essential oil (200 and 400 ppm) were added to antioxidant free soybean oil. To prepare active packages, the oil was filled in antioxidant active high‐density polyethylene (HDPE) bottles containing synthetic antioxidant (3700 ppm) and the essential oil (3700 and 8400 ppm). Regarding peroxide and thiobarbituric acid values, the essential oil added to the oil delayed the oil oxidation more than BHT. In active packages, the synthetic and natural antioxidants migrated from the package to the oil (with 68 and 100 % migration rate, respectively) and retarded its oxidation over the storage time. However, no significant difference was observed between essential oil and BHT in antioxidant capacity for active packages. This study demonstrated that active packages containing antioxidants could be introduced as a good replacement for direct addition of synthetic antioxidants to the oil.     

合成橡胶常压氢化及产物性能

简介了合成橡胶的３种常压氢化方法：（１）用水溶性Ｗｉｌｋｉｎｓｏｎ催化剂在常压氢下使合成胶所合成胸乳在常压与氢化。指出第３种方法最有发展前景,用此方法除了可制备氢化度高的丁腈胶乳外,不可制备具有热塑性弹性体性质的氢化丁苯胶乳及氢化聚丁二烯胶乳;最后二者不经硫化即可用于制备老化的浸渍制品、涂料、粘接剂、复合垫片等。     

抗氧剂GS在稀土顺丁橡胶(NdBR)中的应用

以2-[1-(2-羟基-3,5-二特戊基苯基)-乙基]-4,6-二特戊基苯基丙烯酸酯(简称GS)作为稀土顺丁橡胶NdBR的防老剂,添加量为生胶质量的0.25%,制成实验胶样。100℃进行了热氧老化实验,老化时间84 h,测试其在热氧老化过程中门尼黏度和凝胶质量分数的变化。用差式扫描量热法(DSC)评价胶样在140℃加速氧化中的抗老化性能。与添加抗氧剂2,6-二叔丁基对甲酚(BHT)0.65%(质量分数)的胶样相比,GS作为抗氧剂的胶样,凝胶质量分数为11.9%、门尼黏度ML(1+4)100℃为51.8、氧化诱导期为110.9 min,而BHT的凝胶质量分数为59.7%、门尼黏度ML(1+4)100℃为75.2、氧化诱导期为68.5 min。热重法分析了抗氧剂GS、BHT的热稳定性,其热失重温度分别为230、100℃。     

Effectiveness of antioxidants on lipid oxidation and lipid hydrolysis of cod liver oil

The capacity of the natural antioxidant from barley husks to retard oxidation of PUFA in cod liver oil (Gadus morhua) was investigated and compared to synthetic antioxidants. The results confirm the efficacy of a natural antioxidant derived from barley husks to slow down the progress of lipid hydrolysis and increase oxidative stability in cod liver oil. The rates of lipid hydrolysis and lipid oxidation were slowed down with increasing concentration of natural antioxidant used. Using 100 mg of the natural antioxidant was more effective than some synthetic antioxidants (BHA 200 mg and BHT 200 mg) against primary and secondary oxidation. The use of propyl gallate (PG) as an antioxidant (200 mg/kg in cod liver oil) was the most effective antioxidant employed in reducing the production of primary and delaying secondary oxidation products. The formation of free fatty acids (FFA) was significantly lower in samples with natural antioxidant (BE200 and BE100) than in the control samples. BHA and BHT were the most effective antioxidants employed to delay the lipid hydrolysis. Practical applications: The use of barley husks, which are residues of the brewing process, was optimized to obtain a crude antioxidant extract. Natural extracts of phenolic compounds with high antioxidant activity were obtained after prehydrolysis and delignification of barley husks. The raw extracts show more than two‐fold antioxidant capacity compared to BHT in terms of EC50. The results demonstrate the efficacy of a natural antioxidant derived from barley husks. The extract could be used in fatty foods (such as butter, oil, etc.) to prevent rancidity.     

Antioxidant Activity of Oat Malt Extracts in Accelerated Corn Oil Oxidation

Oat cultivar AC Vermont was malted to concentrate antioxidants, milled to fractionate only the endosperm portion and extracted with methanol to isolate the crude antioxidants. The oat malt antioxidant fraction was assessed as a natural antioxidant based upon enhancing the stability of corn oil against oxidation and compared to the synthetic antioxidant butylated hydroxytoluene (BHT). The induction time (time required for the formation of 10 meq hydroperoxide per kilogram corn oil thermally oxidized) was used to measure antioxidant activity of oat antioxidant or BHT. The protection factor achieved by crude oat malt antioxidant extract concentrate at 0.26% (2,600 μg/g) was comparable to BHT (75 μg/g). The antioxidant activity of the oat and barley malt extract concentrates was not significantly different. However, the extract concentrate of oat malt had 44% less color compared to that of barley malt at equal concentrations showing its potential as a natural food antioxidant.     

Theoretical and Kinetic Tools for Selecting Effective Antioxidants: Application to the Protection of Omega-3 Oils with Natural and Synthetic Phenols

Radical-scavenging antioxidants play crucial roles in the protection of unsaturated oils against autoxidation and, especially, edible oils rich in omega-3 because of their high sensitivity to oxygen. Two complementary tools are employed to select, among a large set of natural and synthetic phenols, the most promising antioxidants. On the one hand, density functional theory (DFT) calculations provide bond dissociation enthalpies (BDEs) of 70 natural (i.e., tocopherols, hydroxybenzoic and cinnamic acids, flavonoids, stilbenes, lignans, and coumarins) and synthetic (i.e., 2,6-di-tert-butyl-4-methylphenol (BHT), 3-tert-butyl-4-hydroxyanisol (BHA), and tert-butylhydroquinone (TBHQ)) phenols. These BDEs are discussed on the basis of structure–activity relationships with regard to their potential antioxidant activities. On the other hand, the kinetic rate constants and number of hydrogen atoms released per phenol molecule are measured by monitoring the reaction of phenols with 2,2-diphenyl-1-picrylhydrazyl (DPPH^•) radical. The comparison of the results obtained with these two complementary methods allows highlighting the most promising antioxidants. Finally, the antioxidant effectiveness of the best candidates is assessed by following the absorption of oxygen by methyl esters of linseed oil containing 0.5 mmol L⁻¹ of antioxidant and warmed at 90 °C under oxygen atmosphere. Under these conditions, some natural phenols namely epigallocatechin gallate, myricetin, rosmarinic and carnosic acids were found to be more effective antioxidants than α-tocopherol.     

Antioxidant effect of natural phenols on olive oil

The total polar fraction and individual phenols present in virgin olive oil were tested for their antioxidant effect in refined olive oil. Hydroxytyrosol and caffeic acid showed protection factors greater than BHT. Protocatechuic and syringic acid were also found to have antioxidant activity. Tyrosol, p-hydroxyphenylacetic acid, o-coumaric acid, p-coumaric acid, p-hydroxybenzoic acid and vanillic acid had very little or no effect, and their contribution to the stability of the oil is negligible.     

Antioxidant Activity of Osage Orange Extract in Soybean Oil and Fish Oil during Storage

The food industry is seeking natural antioxidants for edible oils that have comparable activity to synthetic counterparts. In this study, Osage orange extract (OOE) rich in osajin (42.9%) and pomiferin (30.0%) was obtained after hexane extraction of the fruit, and its antioxidant activity was examined in stripped soybean oil (SBO) and fish oil (FO), in which antioxidants and polar compounds were removed. The antioxidant activity of OOE was compared with commercial natural antioxidants (i.e., rosemary extract and mixed tocopherols) and a synthetic antioxidant, butylated hydroxytoluene (BHT), during storage at 25 and 40 °C. The 0.1% OOE had stronger antioxidant activity than 0.1% rosemary extract and 0.1% mixed tocopherols in both oils at 25 and 40 °C. Its activity was similar to 0.02% BHT in SBO and was similar or slightly stronger than 0.02% BHT in FO. When OOE was studied at 0.05, 0.1, and 0.2%, there was a weak dose–response in SBO but a stronger dose–response in FO. Headspace volatile analysis using solid phase micro-extraction (SPME) combined with GC–MS indicated that 0.1% OOE was very effective in preventing the formation of volatile oxidation products in both oils. Although it should be further tested for safety before the actual use, this study shows that OOE can be developed as an antioxidant for edible oils.     

复合型受阻酚抗氧剂的制备及清除DPPH·活性研究

以二苯基氯化磷和2,2′亚甲基双(4甲基6叔丁基苯酚)为原料,合成具有亚磷酸酯及受阻酚结构的复合型抗氧剂2(2羟基3叔丁基5甲基苄基)4甲基6叔丁基苯基二苯基亚磷酸酯,产率为65.12 %,产物经FT-IR表征,符合理论设计构型。将产物与商用抗氧剂2,6二叔丁基4甲基苯酚(BHT)进行热稳定性及DPPH自由基清除能力的对比测试,结果表明,产物较抗氧剂BHT分子量更高,热稳定性更好;同时其对DPPH自由基具有良好的清除效果,其抗氧化能力强于抗氧剂BHT。