抗氧剂F对聚甲醛热稳定作用的研究

采用220℃等温热失重率、222℃等温热失重速率、平衡扭矩、多次加工及长期热稳定性等分析方法研究对比了高相对分子质量受阻酚类抗氧剂F与Irganox245对聚甲醛(PCIM)的热稳定作用。结果表明:抗氧剂F可有效改善POM的热氧稳定性能。经五次挤出加工,试样的熔体流动速率(MFR)及黄色指数(YI)均较Irganox245低, MFR上升程度显著低于Irganox245,断裂伸长率及冲击韧性均较Irganox245高;经140℃长期热氧老化,试样的 MFR、YI及力学性能均与使用Irganox245相当,表明抗氧剂F能有效延长POM制品的热、氧寿命,其热稳定效能达到 Irganox245的水平,且用量较少,可将其推广应用于POM的生产中,进一步提高POM的热稳定性,降低生产成本。     

助剂对聚甲醛常温颜色稳定性的影响研究

在聚甲醛中添加不同助剂体系,通过室温放置20 d和140 ℃烘箱加速老化7 d处理后,测定物料的黄色指数、熔体质量流动速率、拉伸强度、冲击强度变化,对助剂体系在聚甲醛中的应用进行了评价.结果表明,抗氧剂Irganox1010对聚甲醛的颜色变化有很大影响,引入金属减活化剂后,提高了聚甲醛在常温环境中的颜色稳定性,同时也较好地保持了聚甲醛的各项性能.     

复合型抗氧剂在ABS接枝共聚物中的稳定作用

采用乳液聚合方法制备丙烯腈-丁二烯-苯乙烯(ABS)接枝共聚物,将受阻酚类抗氧剂三甘醇双-3-(3-叔丁基叫-经基-5-甲基苯基)丙酸酯(Irganox245)和β-(4-羟基-3,5-二叔丁基苯基)丙酸正十八碳醇酯(Irganox1076)与硫醋类抗氧剂硫代二丙酸二月桂酯(DLTP)及其复配后的抗氧剂以乳液的形式加到ABS胶乳中。通过测定粉料的老化变黄时间、热失重率、老化后的ABS树脂的黄色指数的变化等方法对单组分抗氧剂和复配抗氧剂在ABS中的稳定作用进行了研究。结果表明:Irganox245和DLTP复配后产生强协同效应,而工rganox1076和DLTP复配后的抗氧化效果和工rganox1076单独使用时的效果相当,只产生比较弱的协同作用。同时也证实了ABS的降解始于双键的断裂,然后与氧结合生成烷氧基化合物、过氧化物和碳基化合物.     

抗氧剂Irganox1010对聚氨酯弹性体老化性能的影响

通过傅里叶红外变换光谱、热分析与力学性能测试,研究了抗氧剂四(3,5-二叔丁基-4-羟基苯丙酸)季戊四醇酯(Irganox1010)对聚氨酯弹性体老化性能的影响。力学测试结果表明,150℃下老化48h后,未加抗氧剂的聚氨酯弹性体的拉伸强度与老化前相比较下降11.6%,而添加抗氧剂的聚氨酯弹性体的拉伸强度与老化前相比较没有下降。热重分析、差示扫描量热分析和红外光谱分析结果表明,抗氧剂Irganox1010能阻碍聚氨酯分子链的断裂,减缓材料的老化,因此能促进聚氨酯弹性体的抗老化性能。     

苯并呋喃酮类复合抗氧剂在聚丙烯中的应用研究

采用多次挤出的熔体流动速率和氧化诱导期(OIT)方法研究了4种不同结构苯并呋喃酮与抗氧剂1010及168的三元复合抗氧体系对聚丙烯(PP)加工稳定性和热氧稳定性的影响。结果表明:在挤出温度为250℃,添加浓度均为1 g/kgPP 的情况下,含5-叔丁基-7-甲基3(4-甲氧基苯基)-3-氢-苯并呋喃2-酮(ANBF2)的三元复合抗氧剂所稳定 PP 在5次挤出之后的熔体流动速率最小,具有最优的加工稳定性;同时 OIT 值最大,体现出在含氧条件下最好的热稳定性。在保持 ANBF2/1010/168三元复合抗氧体系中1010和168的添加量不变情况下,降低了 ANBF2的含量与工业化产品 Irganox HP-2225比较,当 ANBF2添加量仅为 Irganox HP-136添加量的1/3时,ANBF2/1010/168三元复合抗氧剂仍具有比 Irganox HP-2225更优的加工稳定性和热氧稳定性。     

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。     

三种组成不同多支链酚类抗氧剂的合成和评价

合成了抗氧剂改性第二代、第三代和第四代Boltron。3-（3，5-二叔丁基-4-羟基苯基）丙酸是连接到三种不同多支链聚酯的活性基团。合成成功地实现了高度取代。抗氧剂使用示差扫描量热法（DSC）测定在角鲨烷中和在聚丙烯（PP）软片中的氧化诱导时间（OIT）来评价。它们和按0．1％（重量）加入的工业用抗氧剂Irganox 1010相比较，所有合成的抗氧剂在角鲨烷中均比Irganox 1010好，不过对PP稳定性所起的作用则不太大。由于低流动性和低溶解性所导致的多支链抗氧剂在PP中的低抗氧性能可以得出上述结论。     

新型三元复配抗氧体系的设计及其在煤基均聚PP中的应用

设计了一系列由主抗氧剂、辅助抗氧剂、碳自由基捕捉剂组成的不同种类、不同配比抗氧剂体系,并将其用于煤基均聚聚丙烯（PP）的抗热氧老化性能改性中。其中以巴斯夫抗氧剂 Irganox®1010、Irgafos®168主辅抗氧剂质量比1∶1为对比基准,通过测试并对比添加新型三元复配抗氧体系改性 PP的氧化诱导时间（OIT）、黄色指数、熔体流动速率、力学性能等性能指标,从而开发煤基均聚PP的最佳耐热氧老化助剂配方。结果表明,当主抗氧剂为Irganox®1010、辅抗氧剂为 Irgafos®168质量比为 1∶1并与羟胺类抗氧剂 Revonox®420复合使用时,改性 PP的 OIT最长为 9. 8 min,黄色指数为 1. 3,熔体流动速率为 10. 7 g/10 min,综合性能最佳;当主抗氧剂为 Irganox®1010、辅抗氧剂为 Irgafos®168质量比为1∶2时,改性PP的抗黄变效果最好,由此设计并优化的抗氧剂体系及其配比对煤基均聚PP的耐长期热氧老化 改性配方设计具有重要的启示。     

抗氧剂3114抗氧化老化性能研究

研究了抗氧剂3114在PP树脂中的抗氧化老化性能，并与抗氧剂1010进行了对比。研究结果表明：添加抗氧剂3114的PP树脂具有良好的加工稳定性能和长期热氧稳定性能，并可改善PP树脂机械力学性能。而且其热稳定性能接近于抗氧剂1010，耐侯性能则明显优于抗氧剂1010。     

抗氧剂对聚苯乙烯树脂加工稳定性的影响

通过测定聚苯乙烯(PS)树脂的氧化诱导时间、黄色指数及多次挤出前后的熔体流动速率(MFR)、热空气老化前后的力学性能,研究了抗氧剂1010及其与抗氧剂168复配对PS树脂加工稳定性的影响。结果表明:受阻酚类抗氧剂1010和亚磷酸酯类抗氧剂168能够产生很好的协同作用,在多项指标上要远优于只添加抗氧剂1010的体系;在抗氧剂1010/168复配体系中,抗氧剂168用量2倍于抗氧剂1010时,PS的综合性能较佳;当抗氧剂总用量超过1%时,反而会使PS树脂的加工稳定性和力学性能有所下降。     

Study on the High Efficiency Antioxidant of Polyoxymethylene

This article reports on the properties and uses of antioxidant F/B, a type of high efficiency antioxidant for polyoxymethylene (POM), consisting of the hindered phenolic main antioxidant, the secondary thermostabilizer phosphite ester, and lactone compound. Our experimental studies focused on the thermostabilization effect of antioxidant F/B on POM, which was measured by isothermal weight loss analysis at 220°C, isothermal weight loss rate analysis at 222°C, balance torque analysis, nonisothermal gravity analysis (TGA), oxidation induction time (OIT) analysis, and multiple processing and long-term aging analysis as compared to the commonly used antioxidant Irganox245 of POM. The results showed that the thermal stability of POM can be improved remarkably by using antioxidant F/B. The aging mechanism of POM under heat and oxygen was studied by the measurements of polarized light microscopy (PLM), differential scanning calorimetry (DSC), and X-ray photoelectron energy spectrum (XPS), which showed very slight changes of spherulites dimension, crystallinity, and the surface atom concentration after 15 days of aging at 140°C. Furthermore, the small amount of degradation of POM only occurred in the amorphous region of POM. These experiments demonstrated that lower amounts of antioxidant F/B can reach the same level of thermal stabilization of POM as is achieved with higher amounts of Irganox245, and can replace Irganox245 for use in the production of POM, which can further improve the thermal stabilization and reduce the production cost of POM.     

Thermo-Oxidation of Polyethylene Stabilized with Irganox 1010 and Tinuvin 622

Abstract

Thermal oxidation of polyethylene stabilized with the mixture of Irganox 1010 and sterically hindered amine Tinuvin 622 confirmed that the occurrence of synergism or antagonism in the effect of sterically hindered amines towards antioxidants is concentration dependent. Provided that the concentration of phenolic antioxidant Irganox 1010 in polytheylene exceeds that of Tinuvin 622, synergism is observed at 185 and 190°C. Chemiluminescence, oxygen absorption method, nonisothermal differential scanning calorimetry (DSC) and differential thermal analysis (DTA) were used for testing of stabilizing efficiency of mixtures of stabilizers and the mutual correspondence of the results have been pointed out.     

聚酰胺和双氰胺稳定聚甲醛的研究

研究了在主抗氧剂Ｉｒｇａｎｏｘ２４５存在下,聚酰胺（ＰＡＴ）和双氰胺（ＣＧ）稳定共聚甲醛（ＰＯＭ）的效果。研究表明ＰＡＴ与ＣＧ并用有较好的协同作用,当Ｉｒｇａｎｏｘ２４５用量为０５％、ＣＧ０３％、ＰＡＴ０１％时可达到最佳的稳定化结果,在２２０℃下加热１ｈ共聚甲醛的热失重率仅为０３６５％     

Performance and synergistic effect of phenolic and thio antioxidants in ABS graft copolymers

The synergistic effect of phenolic and thio antioxidants on the stabilization of acrylonitrile-butadiene-styrene (ABS) graft copolymers has been studied. Three commercial antioxidants Irganox245, Irganox1076 and dilauryl thiodipropionate (DLTP) were selected. Formulations based on hindered phenols and secondary antioxidant DLTP were prepared. Stabilization was monitored in terms of changes in the functional groups (oxidation products), tensile properties and yellowness index. Differential scanning calorimetry (DSC) and thermogravimetry (TG) were also used to assess the stability. The results indicated that the combination of Irganox245 and DLTP showed much better stabilization effect than the individual components due to the strong synergistic effect. Only weak synergism could be observed in the formulation that contained Irganox1076 and DLTP. Irganox1076 and Irgnox1076/DLTP exhibited similar behaviors between antioxidants with the highest and lowest efficiencies.     

Investigating effect of ferric stearate on stabilization efficiency of a phenolic antioxidant during thermal oxidation of polyethylene

This study aimed to achieve a formulation for an additive to produce oxo-biodegradable films that accelerates oxidative degradation of the films after preservation of properties over a span of desired service life. Thermal oxidation behavior of high-density polyethylene (HDPE) films (approximately 250 μm thick) containing various weight ratios of a commercially used phenolic antioxidant (Irganox 1010) to ferric stearate as pro-oxidant has been studied in both melt and solid states. Thermo-oxidative stability in melt state was studied using differential scanning calorimetry. The rate of thermal oxidation in solid state was investigated via oven aging experiments at 90 °C followed by measuring changes in tensile properties, gel content, carbonyl index and density. Comparing thermo-oxidative stability of the HDPE samples containing a combination of Irganox 1010 and ferric stearate with the samples containing Irganox 1010 alone confirmed that ferric stearate reduces the stabilization efficiency of the phenolic antioxidant in the polymer either in melt or in solid state. It was also shown that the efficiency of the phenolic antioxidant in thermo-oxidative stabilization of the polymer in both melt and solid states could be changed by altering weight ratio of Irganox 1010/ferric stearate. On the basis of the obtained results, it was concluded that weight ratio of 0.1/0.1 wt% of the antioxidant to the pro-oxidant is suitable for attaining desired stability during melt processing as well as retaining properties during a reasonable service life when is used as a film and a favorable rate of thermal oxidation after the service life.     

Water extraction and degradation of a sterically hindered phenolic antioxidant in polypropylene films

Water extraction of the sterically hindered phenolic antioxidant Irganox 1010 from three polypropylene based polymeric films has been studied in isothermal conditions at 40, 50 and 70 °C. The films made of isotactic polypropylene and two different heterophasic polypropylene/ethylene–propylene monomers copolymers (PP/EPM copolymers) were immersed in closed water baths under nitrogen atmosphere in order to minimise the oxidative process. The amounts of antioxidant that have left the films and are dissolved in the water bath have been monitored over time by HPLC analysis and faster extraction kinetics were observed from the polymers than from the homopolymer. No appreciable amounts of Irganox 1010 were found in the extraction water at any time, whereas its degradation by-products were found by LC/MS analysis in the extraction water.

The experimental extraction kinetics from the three polymers were compared with the theoretical curves based on the Fick's diffusion equations solved both for a semi-infinite (degradation reaction faster than extraction) and a finite system (no degradation reaction) and Irganox 1010 was demonstrated to be extracted by water from polypropylene based material faster than predictable only on the basis of the values of its coefficient of diffusion in the polymers and of partition between water and polymer.     

Electron‐beam irradiation of low‐density polyethylene in the presence of phenolic stabilizer,carboxylic acid stabilizer,or both

The effects of Irganox 1010 and citric acid as antioxidants and modifiers of the network structure and mechanical and thermal properties of low‐density polyethylene (LDPE) during electron‐beam crosslinking with different irradiation doses (up to 120 kGy) were investigated. The results showed that the addition of these stabilizers had a retarding effect on the gel fraction of LDPE within the investigated range of electron‐beam‐irradiation doses. However, a noticeable effect on the gel fraction was found for the LDPE formulations compounded with citric acid alone or with its mixture with Irganox 1010 (in an equal ratio), as illustrated by a study of the gel‐fraction/dose relationships. Tensile testing measurements showed that the addition of both stabilizers caused a slight reduction in the stress at break and an increase in the strain at break. On the other hand, the thermal properties of the LDPE batches crosslinked with electron‐beam irradiation were greatly improved as a result of the compounding with these stabilizers, as shown by thermogravimetric analysis studies. In this respect, the temperatures at different weight losses, the temperatures of the maximum rate of thermal decomposition, and the activation energies indicated that compounding with citric acid was more effective for stabilization against thermal decomposition than compounding with Irganox alone or a mixture. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1275–1286, 2005     

耐候性聚氨酯用稳定剂

介绍了聚氨酯的稳定化机理,综述了用于聚氨酯的紫外线吸收剂、抗氧剂、光稳定剂的一些品种。讨论了紫外线吸收剂(UV-571、UV-328)、抗氧剂(Irganox 1010、Irganox 1135、Irganox3125),受阻胺(HALS)(UV-770、UV-765)等稳定剂对聚氨酯光氧老化的影响,结果表明,同时使用上述3类稳定剂可得到较好的效果。     

Effects of chemical structure of phenolic antioxidants on Ziegler–Natta catalyst performance during propylene polymerization

Present work studied the synthesis of in-reactor stabilization of polypropylene via introducing antioxidant into polymerization media. Special attention was dedicated to assess the efficiency of antioxidant in catalyst deactivation. Three different types of antioxidants (Irganox 1076, Irganox 1010 and Irganox 1330) which contain ester and/or phenolic OH functional groups were chosen to investigate their impact on Ziegler–Natta catalyst performance during slurry propylene polymerization. Our Results indicated that not only phenolic OH groups but also esteric bond of antioxidants are capable of interacting with active center of catalyst and consequently decreasing the catalyst activity. Our propylene polymerization results showed that determining factors such as antioxidant chemical structures and its steric hindrance effect and the number of functional groups (phenolic and esteric groups) affected on the Ziegler–Natta catalyst performance. Therefore, effects of these three types of antioxidants on polymer characteristics such as particle size distribution, morphology, T _m , T _c , X _c , and isotacticity were evaluated. Morphological analysis using scanning electron microscopy (SEM) showed that introducing antioxidant during propylene polymerization did not destroy the spherical morphology of the polypropylene particles. Conclusively, due to the negative effect of esteric bond of antioxidant on Ziegler–Natta catalyst performance, the use of antioxidant without ester groups (Irganox 1330) is more recommended during propylene polymerization.