聚丙烯耐老化改性研究

分别采用抗氧剂(1010或1076)及光稳定剂(UV-531或UV-770)作为抗老化助剂对聚丙烯(PP)进行了改性,考察了两类抗老化助剂对PP耐老化性能的影响。结果表明:两类抗老化助剂的添加分别改善了PP的耐热氧老化性能和耐紫外光老化性能。其中,抗氧剂1010对PP耐热氧老化性能的改善效果优于1076,二者的适宜添加量均为0.2%左右;光稳定剂UV-531对PP耐紫外光老化性能的改善效果优于UV-770,二者的最佳用量约为0.3%左右。     

LDPE耐候棚膜专用料2F0.4B的研制与开发

通过光稳定剂的选择及浓度的确定。复配抗氧剂体系的研究。开发生产了低密度聚乙烯耐候棚膜专用料2F0.4B,并对产品进行了性能考核，棚膜大田应用试验。结果表明：2F0.4A-1的力学性能，耐老化性能最佳。适宜作为该专用料的基础树脂；聚合型受阻胺光稳定剂B的光稳定效果最好；膜厚0.10mm时，光稳定剂B的最小加入量0.20%；膜厚0.08mm时，光稳定剂B的最小加入量0.22%；选择合理的复合抗氧剂体系可以获得良好的抗热氧老化以及抗背板效应；含相同助剂，厚度不同（0.06,0.08,0.11mm)的棚膜老化前期差异不明显。老化后期较薄的膜力学性能衰减迅速。     

LDPE耐候棚膜专用料2F0.4B的研制与开发

通过光稳定剂的选择及浓度的确定、复配抗氧剂体系的研究，开发生产了低密度聚乙烯耐候棚膜专用料2F0．4B，并对产品进行了性能考核、棚膜大田应用试验，结果表明：2F0．4A－1的力学性能，耐老化性能最佳。适宜作为该专用料的基础树脂； 聚合物受阻胺光稳定剂B的光稳定效果最好；膜厚0．10mm时，光稳定剂B的最小加入量0．20％，膜厚0．08mm时，光稳定剂B的最小加入量0．22％，选择合适的复合抗氧剂体系可以获得良好的抗热氧老化以及抗背板效应；含相同助剂，厚度不同（0．06，0．08，0．11mm)的棚膜老化前期差异不明显，老化后期较薄的膜力学性能衰竭迅速。     

受阻胺光稳定剂对PP织物抗热老化性能的影响

研究受阻胺光稳定剂对聚丙烯(PP)织物抗热老化性能的影响。受阻胺光稳定剂不仅具有优异的光稳定作用,还具有良好的热稳定作用,对PP织物的长期抗热老化作用显著;当酚类抗氧剂与受阻胺光稳定剂以1∶3的比例组合使用时,达到最佳的配合效果。     

聚乙烯材料耐候性能研究进展

综述了聚乙烯材料耐候性能的影响因素,包括自身结构因素及外部环境因素;系统分析了聚乙烯的老化机理,主要有热氧老化、光氧老化和环境应力开裂,其中前两者都与自由基链式反应有关;最后概括了改善聚乙烯材料耐候性能的方法,主要为添加抗氧剂、光稳定剂和控制加工工艺。     

抗氧剂和光稳定剂对线形低密度聚乙烯氙灯老化的稳定作用

采用氙灯老化的方法研究了抗氧剂1010,168与光稳定剂622对线形低密度聚乙烯(PE-LLD)的影响，并通过拉伸性能测试和凝胶渗透色谱分析对老化前后PE-LLD的性能和结构进行了研究。结果表明，未添加抗氧剂、光稳定剂的PE-LLD经氙灯老化3d后断裂伸长保留率小于50%，单独添加0. 15份抗氧剂1010,168或光稳定剂622 , PE-LLD断裂伸长保留率小于50%时，需氙灯老化的天数分别为7,6和15 d。抗氧剂1010,168与光稳定剂622复配使用时，对PE-LLD的杭老化性有明显的协同效应。     

抗氧剂、光稳定剂的基本功能、评价方法及选用原则

论述了塑料抗氧剂、光稳定剂的防老化基本功能及评价方法，特别介绍了受阻胺类光稳定剂的抗热氧老化功能，提出了设计配方时选用抗氧剂、光稳定剂的参考原则。     

农用棚膜耐老化体系开发应用进展

综述了农用棚膜耐老化体系发展概况 ,重点阐述了高分子量聚合型受阻胺光稳定剂与复合型抗氧剂、复合聚合型受阻胺光稳定剂与复合抗氧剂组成的聚烯烃棚膜耐老化体系及其应用效果 ,简要介绍了抗农药型受阻胺光稳定剂开发应用情况 ,并对光学性能稳定化的研究提出了看法。     

功能性聚乙烯棚模的耐老化性能

在LDPE，LLDPE树脂中添加适量受阻按类高效光稳定剂能胆显的提高聚乙烯棚膜耐老化性能，厚度0.08-0.12mm的耐老化功能性聚乙烯彬膜用于覆盖蔬菜大棚，在东北地区能使用二年，社会经济效益可观，文中简述了聚乙烯棚膜耐老化性能评价方法和耐老化聚乙烯棚膜生产技术要点。     

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。     

ABS的耐候老化研究

主要对丙烯腈–丁二烯–苯乙烯塑料(ABS)的不同耐候性能进行了研究,通过人工加速老化试验,对比老化前后色差变化,考察光稳定剂对ABS耐候性能的影响。结果表明,添加光稳定剂能够有效地改性ABS耐候性能;受阻胺光稳定剂与紫外线吸收剂复配使用对ABS有很好的耐候效果;适当地提高受阻胺光稳定剂含量有利于提高ABS的耐候性能。     

Wirksamkeit sterisch gehinderter amine bei anspruchsvollen applikationen von polypropylen

The influence of some types of antioxidants on the efficiency of low molecular hindered amine light stabilizers (HALS) has been investigated in a comparison with the behaving of high molecular HALS. Most of the antioxidants used exhibit favourable influence. Convenience of both low and high molecular HALS in compounds depends on the character of the stabilised product and the technological conditions for its production.     

耐药型受阻胺光稳定剂的发展

介绍了耐药型受阻胺光稳定剂（HALS）的发展。针对低pKa值HALS,含缚酸剂的HALS,以及N-烷基化和N-烷氧基化HALS,详细叙述了典型品种的性能特点,并报道了耐药型受阻胺光稳定剂的最新研究成果。     

Synergistic effect of hindered amine light stabilizers/ultraviolet absorbers on the plasticized PVC during photo-irradiation

Two kinds of piperidine derivatives including a low-molecular weight (Wt. 481, T770) and a high-molecular weight (Wt. 2000–3100, C944) hindered amine light stabilizers (HALS) are added singly or with ultraviolet absorbers (UVA) in combination to plasticized poly(vinyl chloride) (PVC) samples. Digital photos, color changes, attenuated total refection-Fourier transform infrared spectra (ATR-FTIR), and mechanical properties are obtained to investigate the photostable effect of the light stabilizers on the plasticized PVC after artificial aging. PVC samples with HALS perform well at the first 400 h of irradiation in color change, FTIR, and mechanical properties, but at the last 400 h the photostability decreases. Besides, C944 performs better than T770, because C944 is a high-molecular weight UV stabilizer and has good extraction resistance. Plasticized PVC samples with UVA resist discoloring and photooxidation from the photo-irradiation. Excellent synergism is observed between the combination of HALS and UVA. PVC with HALS/UVA performs better than PVC with HALS and PVC with UVA in color differences, FTIR, and mechanical properties. The synergism is due to the different stages of functions between HALS and UVA. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

新型光稳定剂产品应用于水性醇酸涂料的研究

醇酸树脂普遍应用于工业涂料,其暴露在自然太阳光时,容易造成外观上颜色的变化和涂层劣化与粉化,目前这层保护主要是添加紫外线吸收剂(UVA)和酸性系统使用受阻胺光稳定剂(N-OR HALS)来达成。由于环保趋势,水性醇酸涂料已发展成为解决有关一般常用传统高VOC溶剂型涂料,它能够有效减少或不使用溶剂的优点,而环保型涂料所遭遇的挑战之一,是需要光安定剂来保护涂料预防光劣化产生。先针对2种不同类型水性受阻胺光稳定剂N-R HALS(高碱性)和N-OR HALS(弱碱性)混合水性醇酸涂料测试,试验结果显示:N-OR HALS适用于水性醇酸涂料系统。本文主要是有关于应用试验设计(DOE)试验手法,根据实验室人工加速老化试验结果显示,增加水性紫外线吸收剂Eversorb AQ6和水性受阻胺光稳定剂(NOR-HALS)Eversorb AQ5在水性涂料中的有效浓度,可以增强相对的保护效果,试验数据显示膜厚对减缓黄变影响而言也是显著因子,但效果不如添加水性光稳定剂产品有效。     

Theoretical and experimental assessment of UV resistance of high-density polyethylene: Screening and optimization of hindered amine light stabilizers

Hindered amine light stabilizers (HALS) are widely used chemical stabilizers for preventing polymer degradation. In this study, the effects of type of HALS and its content in high-density polyethylene (HDPE) over the stabilization process are investigated employing density functional theory (DFT) and experimental approach. The electrophilicity index of four types of commercial HALS are compared by DFT to select the most effective one. Besides, the HDPE sample containing a phenolic antioxidant and different contents of the selected HALS are experimentally exposed to UV irradiation. The effect of HALS content on the changes in chain microstructure and molecular weight of HDPE are evaluated using gel permeation chromatography and frequency sweep rheometry. In the absence of HALS, HDPE suffers degradation and the phenolic antioxidant causes chain scission. However, by adding HALS, the chain branching and crosslinking mechanisms are predominant. The results of FTIR, DSC, and tensile analyses follow similar trends, revealing that the best stabilization performance corresponds to adding 600 ppm HALS to HDPE.     

Oxygen uptake methods as a tool to determine the mechanism of action of hindered amine light stabilizers1

The UV-degradation of an unstabilized and two HALS stabilized polyethylene (PE) films is described. The degradations are characterized by measuring the oxygen uptake, the formation of CO and CO₂, the FT-IR spectra, the mechanical properties, the stabilizer concentration and the oxygen content of the film. The oxygen uptake of the unstabilized PE film led to the expected changes in the IR spectra and embrittlement of the film, while the oxygen uptake by the HALS stabilized films caused only minor changes. The differences between the results for the unstabilized and the HALS stabilized polymers are explained assuming that the initiation of the photodegradation of PE is due to charge transfer complexes.     

Improved Ultraviolet (UV) Radiation Stability of the Polypropylene (PP) Films of Woven Jumbo Bags for Outdoor Applications

Several formulations were developed with polypropylene (PP) in combination with antioxidants, calcium stearate, hindered amine light stabilizers (HALS) and ultraviolet light absorber (UVA) for making woven jumbo bags, which will be capable of carrying a load of two tons of materials in outdoor conditions. Thin films of these formulations were extruded followed by stretching to improve mechanical properties. Both stretched and un-stretched PP films were subjected to severe accelerated weathering by ultraviolet (UV) radiation for various periods and it was observed that un-stretched films reached 50% retention of tensile strength (TS) within 500 hours of exposure, while stretched films (tapes) did not reach 50% TS retention even after 10,500 hours of the exposure indicating an improved UV stability of the stretched films of PP.