反应型紫外线吸收剂的研究进展

反应型紫外线吸收剂可有效地改善聚合物材料的抗紫外线能力。针对现有反应性紫外线吸收剂的国内外的发展现状和趋势，详细介绍了苯并三唑、二苯酮和受阻胺（HALS）等反应性紫外线吸收剂的制备和应用情况，并展望了其应用前景。     

苯并三唑类紫外线吸收剂的研究进展

介绍苯并三唑类紫外线吸收剂当前发展概况及其改性品种,指出该领域正向着高分子质量、多功能化和反应性化方面发展,其中一些品种已工业化并且用于塑料工业.同时,还详细介绍了苯并三唑类紫外线吸收剂的合成方法.     

防晒剂的发展综述

综述了目前几类应用较多的防晒剂：二苯甲酮、二苯甲酰甲烷、苯并三唑、肉桂酸酯类紫外线吸收剂和二氧化钛、氧化锌类紫外线屏蔽剂以及天然紫外线吸收剂的近几年研究现状;概括了防晒剂的防晒机理;介绍了紫外线吸收剂的高分子化方法,紫外线吸收剂在织物处理洗涤剂中的应用以及日本最近研制出的新产品,并对防晒剂的发展趋势作了分析。     

新型紫外线吸收剂三嗪的合成

三聚氯氰与间二甲苯于50℃反应36 h,再与间苯二酚于110℃反应4 h,合成三嗪类紫外线吸收剂。讨论了反应温度、时间及反应物配比对反应的影响。与苯并三唑类紫外线吸收剂TINU-VIN 326的应用比较发现,三嗪类紫外线吸收剂具有优良的紫外线吸收性,且具有良好的热稳定性和加工稳定性能。     

化妆品防晒剂的研究进展及其安全性问题(待续)

从分子结构特点、光稳定性、应用性能以及安全性等方面综述了已被欧盟化妆品及非食品科学委员会、美国食品及药品管理局、日本厚生省以及中国卫生部批淮使用的化妆品用紫外线吸收剂。对全球近期在该领域的主要研究开发方向进行了综述和分析。三嗪类及苯三唑类衍生物因其优越的光稳定性和安全性仍然是两类研究活跃的化妆品用紫外线吸收剂。尽管高分子类紫外线吸收剂无疑是将来的主力，但要通过美国食品及药品管理局的批淮仍需时日。     

紫外线吸收剂UV—531生产工艺改进试验

本文介绍了二苯甲酮类紫外线吸收剂的性能及应用,说明UV-531的性能优于二苯甲酮类其它产品;并对其生产工艺进行了改进,讨论了存在的问题。1概述紫外线吸收剂UV一石31,化学名称为2一经基一4一正辛氧基二苯甲酮     

邻羟基苯并三唑类紫外线吸收剂的结构与作用特点及发展趋势

邻羟基苯并三唑类紫外线吸收剂,也称羟基苯并三唑类紫外线吸收剂,简称苯并三唑类紫外线吸收剂,是国际、国内消费量最大的一类紫外线吸收型光稳定剂。     

苯并三唑类紫外线吸收剂的现状及发展趋势

综述了不同种类的紫外线吸收剂,着重介绍了苯并三唑类紫外线吸收剂。苯并三唑类紫外线吸收剂由于性能优异而广泛应用于各种高分子合成材料和制品中。但由于其相对分子质量较小,在高分子材料加工过程中,容易通过向表面迁移、表面挥发而引起损失,所以其耐光性比较差。在苯并三唑类紫外线吸收剂分子中引入可聚合的基团使它可以和不同的单体聚合成高分子化合物。从共价键到聚合物链的转变使其在介质中更稳定,更不易迁移和挥发。含有可聚合基团的紫外线吸收剂相比普通的紫外线吸收剂显示出了相当优良的耐光稳定性。     

超高效液相色谱法同时测定电子电气塑料部件中6种苯并三唑类紫外线吸收剂

建立了电子电气塑料部件中6种苯并三唑类紫外线吸收剂的超高效液相色谱分析方法。采用该方法对市售电子电气塑料部件进行了检测,结果表明:6种苯并三唑类紫外线吸收剂的检出限均为0.2 mg/kg,在3个不同加标水平下,方法的平均加标回收率为81.63%~93.64%,相对标准偏差为0.75%~3.98%,并在部分样品中检出了不同含量的苯并三唑类紫外线吸收剂。该方法操作简便、重复性好、灵敏度高,适用于电子电气塑料部件中6种苯并三唑类紫外线吸收剂的同时测定。     

二苯甲酮类紫外线吸收剂发展趋势

本文介绍了二苯甲酮类紫外线吸收剂国内外发展及其光稳定化机理,着重介绍了紫外线吸收剂 UV—B 的合成工艺及其性能,证明该品种是一种工艺简单,成本低廉,性能优良的新型紫外线吸收剂,同时也指出了二苯甲酮类紫外线吸收剂应向多功能及反应型方向发展。     

Photoprotection of Wood Using Polyester-Type UV-Absorbers Derived from the Reaction of 2-hydroxy-4(2,3-epoxypropoxy)-benzophenone with Dicarboxylic Acid Anhydrides

Abstract

Polyester-type UV absorbers were created by reacting the epoxy-functionalized UV absorber 2-hydroxy-4(2,3-epoxypropoxy)-benzophenone (HEPBP) with maleic, phthalic, or succinic anhydride. The ability of the UV absorbers to photostabilize wood was then examined. Fourier transform infra-red (FTIR) spectroscopy confirmed that HEPBP reacted with phthalic anhydride to create a polyester that preserved the UV-absorbing benzophenone group. There was less evidence that the polyester was formed when HEPBP was reacted with maleic or succinic anhydride. HEPBP-phthalic anhydride was the most effective UV absorber at photostabilising wood. This UV absorber showed increased UV absorption around 270 nm, formed a leach-resistant film at wood surfaces and was able to restrict both weight and tensile strength losses of thin wood veneers during accelerated weathering, unlike chromium trioxide and a UV absorber-hindered amine light stabilizer. We conclude that polymeric polyester-type UV absorbers show promise as a way of photostabilizing wood and briefly discuss how more effective systems could be developed in future.     

Graft-copolymerization of PVC with polymerizable UV absorbers

Summary Polyvlnyl chloride has been grafted with two different monofunctional polymerizable ultraviolet (UV) absorbers, 4-methacryloyloxy-2-hydroxybenzophenone and 2(2-hydroxy-4-methacryloyloxyphenyl) 2H-5-methoxy-benzotriazole. PVC was activated by dehydrochlorinating it in pyridine and subsequently grafted with the monomeric UV absorbers in tetrahydrofuran by free radical polymerization. The molar masses of the resulting grafted polymers and the distribution of the UV absorber moleties along different molar mass fractions were determined by GPC. It was shown that in addition to the grafting reaction, recombination of the DHPVC and homopolymerization of the UV absorber molecules take place.     

天来施M的双重物理防晒作用机理及其安全性的探讨

论述了高效光稳定的UVA紫外线吸收剂天来施M的双重物理防晒机理 ,并对其在实际应用中的安全性进行了研究探讨。同时将天来施M与其它UVA防晒剂的作用机理及应用安全性进行了比较。     

UV吸收前体在热敏相纸中的应用研究

UV吸收前体(UVP)是应用于热敏相纸中的一类特殊的紫外吸收剂,它本身不能吸收紫外光,在一定条件下(紫外光和氢质子提供剂)可生成有效的紫外吸收剂,本文就其形成机理进行了简述,同时研究了3种UV吸收前体在热敏相纸中的应用情况。     

Photoprotective agents for wool. Synergism between UV absorbers and antioxidants

Several antioxidants alone, and in combination with sulfonated UV absorbers, have been evaluated as photoprotective agents for wool. Mixtures of phenolic antioxidants and sulfonated UV absorbers of the 2-hydroxyphenylbenzotriazole class were found to exhibit synergistic behavior; the most effective UV absorber also gave the strongest synergistic effect with the antioxidants. Of the systems studied, the hindered phenol, calcium bis ((ethyl-(3,5-di-t-butyl-4-hydroxybenzyl)-phosphonate)) (Irganox 1425), when used in conjunction with a sterically hindered benzotriazolesulphonate, afforded wool the best protection against photoyellowing and phototendering in sunlight, behind window glass. Sulfonated derivatives of hindered phenols acted synergistically with UV absorbers when treated fabrics were exposed to an artificial light source, but not when fabrics were exposed to sunlight through glass.     

UV absorber aftertreatment to improve lightfastness of natural dyes on protein fibres

The effect of a UV absorber on the lightfastness of natural dyes has been investigated. Wool and silk fabrics, dyed with natural dyes with or without mordants, were aftertreated with two UV absorbers. This treatment improved the lightfastness of the mordant-dyed fabric without affecting its colour or shade. The extent of photofading was evaluated by measuring the colour difference, Δ E , of the dyed sample before and after a 20 h period of irradiation under a xenon arc lamp. The uptake of the UV absorber on wool was much higher than that on silk.     

Photodegradation of UV absorbers: Kinetics and structural effects

When poly(methyl methacrylate) films containing UV absorbers are exposed to UV light, the absorbers undergo photodegradation resulting in loss of absorbance. If the data extend for less than one half-life, both zero and first order kinetic treatment give fairly linear fits, but the rate constants so derived are dependent on the initial absorbance of the films. When the zero order rate constants are corrected to account for the higher rate of degradation near the surface compared with the bulk that occurs in highly absorbing films, consistent “infinite absorption” zero order rate constants are derived. The inhomogeneous degradation is due to only the highly absorbed, higher energy light contributing significantly to the degradation. For the benzophenone and benzotriazole classes of absorber, at least 65% of the degradation is due to light with wavelengths < 350 nm. Structural variations generally caused only small differences in the rates of degradation of these classes of absorbers unless the substitutions disrupted the intramolecular hydrogen bonds that are critical for stability. If the hydrogen bond is weakened, the absorber is less stable.     

Preparation and characterization of polymers with pending UV-absorber groups. I. Polymers based on polydimethylsiloxane

The hydrosilylation reaction using dichloro(dicyclopentadiene) platinium (II) as catalyst is carried out to synthesize polymeric UV absorbers with polysiloxane backbone. An almost quantitative addition of vinyl groups of the UV absorber (benzophenone) to silane groups is observed. The IR spectra indicate the qualitative results of the reaction, whereas the ¹H-NMR spectra allow the following of the reaction quantitatively. Low glass transition temperatures are observed by DSC. UV spectroscopy shows that the extinction coefficient and spectra of the UV absorbers are hardly affected by the polymer analogous reaction. © 1994 John Wiley & Sons, Inc.     

Synthesis,characterization, and performance evaluation of novel stabilized TDI‐based polyurethane coatings under accelerated weathering

Some toluene diisocyanate (TDI)‐based polyurethane resins (PURs) for coating applications were synthesized with castor oil and their performance was estimated under accelerated UV weathering with and without a novel UV absorber. Changes in physical properties, chemical structure, and color of the samples were monitored by mechanical property testing, FTIR spectroscopy, and colorimetry, respectively. A stable polyurethane coating was achieved at 0.5% concentration of additive in the host matrix. Mechanical properties were also retained as in the pristine PUR after mixing. Commercial Tinuvin P and benzotriazole‐based novel UV absorbers were found to improve the photoresistance of the PUR coating, and the highest efficiency of the novel UV absorber against weathering was estimated at 0.5 wt% concentration. J. VINYL. ADDIT. TECHNOL. 11:13–20, 2005. © 2005 Society of Plastics Engineers.