新型抗氧剂HD在热塑性弹性体SBS加工中的应用*

采用吸氧量法和热烘箱老化法对新型抗氧剂ＨＤ在热塑性弹性体ＳＢＳ加工中的应用进行了研究。试验结果表明,在１００份ＳＢＳ中加入０８份抗氧剂ＨＤ６的抗氧化效果最好;抗氧剂ＨＤ３和ＨＤ４的抗氧化效果优于抗氧剂１０１０;抗氧剂ＨＤ／１０１０的并用效果优于辅助抗氧剂ＤＬＴＰ／抗氧剂１０１０的并用,抗氧剂ＨＤ３、ＨＤ４和辅助抗氧剂ＤＬＴＰ均与抗氧剂１０７６具有协同效应,抗氧剂ＨＤ３与辅助抗氧剂ＤＬＴＰ的抗氧化效果相近,而抗氧剂ＨＤ５则稍差     

ABS的老化及其防老化

讨论了ＡＢＳ老化及其防老化机理，研究了抗氧剂和紫外线吸收剂对ＡＢＳ耐老化性能影响。结果表明，抗氧剂１０７６和紫外线吸收剂ＵＶ－３２７能有交改善ＡＢＳ的耐老化性能。     

含抗氧剂聚碳酸酯的制备及降解性能研究

通过在聚碳酸酯(PC)中加入不同抗氧剂以提高其热稳定性,研究了抗氧剂的种类、用量、环境条件对PC热稳定件能和降解动力学的影响.结果发现,加入复配抗氧剂能显著提高PC的热稳定性能.在有氧气情况下,抗氧剂的质昔分数增至0.6%时,起始降解温度(以降解率达到5%时的温度计)从原来的472.1℃增加至500.4℃,而最大降解温度(降解速率最大温度)也从原来的530.3℃增加至546.4℃,并应用改良Coats-Redfem法对PC降解动力学做了分析.     

中国塑料抗氧剂生产现状与发展趋势

抗氧剂是聚合物稳定助剂的重要类别，其应用几乎涉及所有的聚合物制品。塑料用抗氧剂通常包括酚类抗氧剂、磷类和硫类辅助抗氧剂以及金属离子钝化剂等，以防止树脂在加工和应用过程中发生氧化降解。     

环氧树脂降解与稳定化研究进展

介绍了环氧树脂的降解机理,综述了国内外近来对环氧树脂光氧化、热降解的研究进展以及通过在环氧树脂中添加光稳定剂和抗氧剂等提高环氧树脂耐候性的技术进展,并介绍了几种新型光稳定剂在环氧涂料和灌封料中的应用。     

不饱和聚酯树脂的降解与稳定化研究进展

综述了不饱和聚酯树脂（UP）的降解机理，UP光稳定性较差，限制了其应用范围，添加适宜的稳定剂可明显改进其光稳定性，从而可用于户外。本文介绍了一些抗氧剂、紫外线吸收剂、受阻胺光稳定剂（HALS）。试验表明，只使用单一的稳定剂效果不佳，必须将主抗氧剂，辅抗氧剂和其他添加剂（例如：某些环氧化合物）并用，才能取得较好的稳定效果。     

受阻酚抗氧剂Ky—586的合成及应用

介绍了受阻酚类抗氧剂Ｋｙ－５８６的合成路线及性能特点，了Ｋｙ－５８６、Ｉｒｇａｎｏｘ１０７６、Ｉｒｇａｎｏｘ２４５在通用聚苯乙烯、高冲聚苯乙烯和聚甲醛中的应用。     

橡胶抗氧剂近况与展望

橡胶抗氧剂主要分为两种：一种为主抗氧剂，又称链终止型抗氧剂（chainbreakingantioxidant），能通过提供氢原子消除过氧自由基ROO，中断自动氧化的链增长以阻止降解；一种为辅助抗氧剂，又称预防型抗氧剂（Preventiveantloxidant），它能借助除去自由基来源，抑制或延缓引发反应中自由基的生成。此种抗氧剂中用量最大、最有发展前途的为烷基、芳香基对苯二胺；其次为酚类、亚磷酸、硫酯等。还有一种复合抗氧剂，是利用主、辅助抗氧剂的协同效应而显示出较大的优越性能，抗氧化活性高、挥发性低，特别适用于橡胶高温加工，且用量少，代表…     

抗氧剂对PMMA树脂热氧化稳定性的影响及动力学分析

采用热重分析,研究了抗氧剂种类及用量对聚甲基丙烯酸甲酯(PMMA)热氧化稳定性的影响,并采用Kis-singer、Flynn-Wall-Ozawa和Flynn法对其热氧化降解行为进行了动力学分析。结果表明,抗氧剂1010、1076、702和BHT的用量为0.5‰时就能够显著提高PMMA热氧化稳定性,使其起始热分解温度提高70℃左右,而抗氧剂用量进一步提高对改善PMMA的热稳定性意义不大;动力学分析表明,抗氧剂的加入能够提高PMMA质量损失率小于30%时的热降解活化能,而热分解后期由于降解温度高于抗氧剂熔点,抗氧剂气化逸出,抗氧剂不能有效提高PMMA后期热降解活化能,未能达到提高PMMA整体热稳定性的目的。     

聚烯烃的热降解机理及热稳定性能研究

采用热失重法分析了超高相对分子质量聚乙烯(UHMWPE)与高黏度聚丙烯(PP)在氧气和空气中的热失重特点,并对加入抗氧剂的UHMWPE在空气中的热稳定性能进行了研究。结果表明:在氮气中,UHMWPE和高黏度PP的热降解属于一级降解反应;空气的存在降低了UHMWPE与高黏度PP的热稳定性,促进了二者的热分解,且UHMWPE出现了氧化增重现象,其热稳定性较高黏度PP差;抗氧剂的存在抑制了氧气的作用,提高了UHMWPE的热稳定性,其中抗氧剂1098(N)的抗氧活性较好。     

Effects of phenolic antioxidants on ultrahigh molecular weight polyethylene/decalin solution

The degradation of ultrahigh molecular weight polyethylene (UHMW‐PE) during its dissolution into decalin is discussed. The stabilization of the solution by three phenolic antioxidants, octadecyl β‐(3,5‐di‐tert‐butyl‐4‐hydroxyphenyl)propionate (1076), tetrakis[methylene‐β‐(3,5‐di‐tert‐butyl‐4‐hydroxyphenyl)propionate]methane (1010), and 1,1,3‐tris(2‐methyl‐4‐hydroxy‐5‐tert‐butylphenyl)butane (CA), and an auxiliary antioxidant, dilaurylthiodipropionate (DLTP) is also discussed. Among the three phenolic antioxidants, 1076 had the greatest effect. The auxiliary antioxidant was effective in stabilizing the solution when combined with one of the three phenolic antioxidants. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 2877–2881, 2000     

抗氧剂增效剂SBDT在聚丙烯中的应用

用环氧大豆油和十二硫醇合成出抗氧剂增效剂SBDT，该增效剂耐挥发、耐抽提。考察了SBDT与酚类抗氧剂1010、1076复配对PP的加工稳定性及长期热氧稳定性的影响，并与DLTP、DSTP和168等辅助抗氧剂的性能进行了对比。实验结果表明：与酚类主抗氧剂复配并用，该增效剂SBDT抗热氧效能比DLTP、168好，有的配方的效能已接近DSTP。     

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.     

Effect of titanium compounds on thermooxidative properties of stabilized polypropylene

The effect of titanium compounds on thermooxidation stability of stabilized polypropylene was studied. It was found that the presence of titanium compounds shortens the induction period of PP oxidation. This phenomenon is brought about by the thermal reactions of titanium compounds with antioxidants which take place during polymer processing. The first step is the reaction of Ti? Cl with OH groups of phenolic antioxidant, which gives rise to a colored titanate and HCl. Hydrogen chloride functions as a Friedel-Crafts catalyst for degradation and dealkylation of phenolic antioxidants. The products of degradation have a very low stabilization efficiency. Hydrogen chloride acceptors suppress antioxidant degradation and increase the polymer stability even in the presence of small amounts of titanium compounds.     

助剂对透明聚氨酯弹性体耐黄变性能的影响

通过正交试验考察了在不同环境下不同的抗氧剂、紫外线吸收剂、助抗氧剂以及光稳定剂对透明聚氨酯弹性体耐黄变性能影响,优化了不同环境下的最佳助剂组成.结果表明:在室内避光条件下影响材料耐黄变性能的助剂主次顺序为助抗氧剂＞紫外线吸收剂＞光稳定剂＞抗氧剂;在室内日光灯照射条件下影响材料耐黄变性能的助剂主次顺序为紫外线吸收剂＞助抗...     

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.     

多乙烯多胺桥联受阻酚类抗氧剂的合成及其清除DPPH·性能

以二乙烯三胺和三乙烯四胺为桥联基,β-(3,5-二叔丁基-4-羟基苯基)丙酰氯为抗氧化功能基团,通过酰胺化缩合反应合成了两类具有不同对位桥联基团的受阻酚类抗氧剂。采用傅里叶红外光谱和核磁共振氢谱证实了合成的多乙烯多胺桥联受阻酚类抗氧剂的化学结构。DPPH法研究了多乙烯多胺桥联受阻酚类抗氧剂清除自由基的性能,并探索了酚羟基个数和对位桥联基结构对受阻酚类抗氧剂清除自由基性能的影响。结果表明,多乙烯多胺桥联受阻酚类抗氧剂具有良好的清除DPPH·能力,且随着抗氧剂分子中酚羟基个数的增加,清除DPPH·的活性增加,分子中含有4个酚羟基的三乙烯四胺受阻酚类抗氧剂的抗氧化效率（AE）达到2.65×10^-2 L/(mol·s)。对位桥联基结构对受阻酚类抗氧剂清除DPPH·能力有较大影响,季戊四醇为桥联基的受阻酚类抗氧剂1010清除DPPH·能力最强,其抗氧化效率（AE）为3.08×10^-2L/(mol·s);乙二胺为核的1.0代树枝状受阻酚类抗氧剂清除DPPH·能力最弱,其抗氧化效率（AE）为2.60×10^-2 L/(mol·s)。     

Process efficiency and long‐term performance of α‐tocopherol in film‐blown linear low‐density polyethylene

α‐Tocopherol was compared with a commercial phenolic antioxidant (Irganox 1076) as a long‐term and process antioxidant in film‐blown and compression‐molded linear low‐density polyethylene. The antioxidant function of α‐tocopherol was high in the film‐blown material, especially in the processing, according to oxygen induction time measurements with differential scanning calorimetry. The residual content of α‐tocopherol after processing, determined with chromatographic techniques, was less than that of the commercial phenolic antioxidant in both the film‐blown and compression‐molded materials. The process stabilizing efficiency was nevertheless higher for the material containing α‐tocopherol. During the long‐term stabilization, the efficiency of α‐tocopherol was less than that of the commercial phenolic stabilizer Irganox 1076 in the thin films, according to chemiluminescence and infrared measurements. The long‐term efficiency in the compression‐molded samples stabilized with α‐tocopherol or Irganox 1076 was equally good because of the low loss of both α‐tocopherol and Irganox 1076 from the thicker films. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2427–2439, 2005     

非对称型受阻酚类抗氧剂的研究新进展

非对称型受阻酚类抗氧剂以其特殊的结构显著提高了聚合物的抗氧化效率,新型非对称型受阻酚的探索与开发代表了当今世界聚合物抗氧化领域的一大发展趋势。简述了非对称型受阻酚类抗氧剂的结构特性及抗氧化机理,重点介绍了几种典型的半受阻酚类抗氧剂的合成及应用,指出了非对称型受阻酚类抗氧剂的研究方向。     

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。