Functional polymers. LIV. Photochemical behavior of 2(2-hydroxyphenyl)2H-benzotriazole derivatives

Summary The absorption spectra of 2(2-hydroxyphenyl)2H-benzotriazoles derivatives substituted with electron-donating and withdrawing groups in various positions on the phenyl ring allowed to estimate the relative stability of the hydrogen-bonded structures as evidenced by the 340 nm/300 nm ratio.Photodegradation studies of poly-cis-1,4-butadiene-1,3 with and without 2(2-hydroxyphenyl) benzotriazole absorbers with various substituents show that compounds with R=H are better photostabilizers than those with RH.Functional Polymers LIII., R.X. Liu, S.K. Wu, S.J. Li, F. Xi, O. Vogl; Polymer Bulletin 20, 59 (1988)     

Functional polymers. LV. Photochemical behavior of 2(2-hydroxyphenyl)2H-benzotriazole derivatives

Summary Polymerizable 2(2-hydroxyphenyl)2H-benzotriazole ultraviolet absorbers have the normal hydrogen bonded maximum at 340 nm. When more than one ortho-hydroxy group capable of hygen bonding is present in the molecule the extinction coefficient increases dramatically; the fluorescence spectra are also affected. It is expected that these compounds are very effective ultraviolet stabilizers.Functional Polymers. LIV., G.S. Dai, S.K. Wu, A. Sustic, F. Xi, and O. Vogl, Polymer Bulletin 20, 67 (1988)     

Functional polymers. LIII. Photochemical behavior of 2(2-hydroxyphenyl)2H-benzotriazole derivatives

Summary The absorption spectra of 2 [2-hydroxy-5-(meth) acryloxyphenyl] 2H-benzotriazoles, their homoand copolymers were studied. The immediate environment (next monomer units in copolymers) determine the details of the spectral characteristics. Copolymers are more efficient in photostabilizing poly-cis-1, 4-butadiene-1, 3 in solution than the monomer or the homopolymer.Functional Polymers LII., S.J. Li, S.K. Fu, O. Vogl; Monatshefte für Chemie, in press     

2-(2′-乙酰氧基-5′-溴甲基苯基)-2H-苯并三唑的合成

2-(2′-羟基-5′-甲基苯基)-2H-苯并三唑(UV-P)经过羟基乙酰化、N-溴代丁二酰亚胺(NBS)溴代,合成了具有高反应活性的2-(2′-乙酰氧基-5′-溴甲基苯基)-2H-苯并三唑。为提高目标产物产率和反应效率,分别对溶剂、引发剂、反应温度、反应时间、反应物投料比和反应底物浓度进行了研究。得出较优合成条件为:氮气保护下,四氯化碳为溶剂,偶氮二异丁腈(AIBN)引发,NBS与2-(2′-乙酰氧基-5′-甲基苯基)-2H-苯并三唑摩尔比1∶1,回流反应1h。在上述条件下,2-(2′-乙酰氧基-5′-溴甲基苯基)-2H-苯并三唑产率为60%。产物经过IR、1HNMR、MS分析证明结构正确。     

2-(2'-羟基-5'-异丙烯酸乙酯基苯基)-2H-苯并三唑的合成

以邻硝基苯胺和对羟基苯乙醇为原料,经过重氮化、偶合、还原和酯化合成了适合于工业化生产的2-(2′-羟基-5′-异丙烯酸乙酯基苯基)-2H-苯并三唑,其结构经核磁共振确证。     

Functional derivatives of (bi)phenyl-substituted carbazoles as building blocks for electro-active polymers

(Bi)phenyl-substituted carbazoles containing reactive functional groups were synthesized by the multi-step synthetic rout. The monomers were examined by various techniques including thermogravimetry, differential scanning calorimetry, UV and fluorescence spectrometry as well as electron photoemission technique. These derivatives were also tested as hole transporting materials in bilayer OLEDs with Alq₃ as the emitter. The devices exhibited promising overall performance with a turn-on voltage of ～3 V, a maximal photometric efficiency of 5.1 cd/A and maximum brightness of 12,200–15,600 cd/m².     

Synthesis and characterization of polymers containing naphthyl-2H-benzotriazoles, 3. Hydrogen bonding in monomers and polymers containing naphthyl-2H-benzotriazole

The UV absorption characteristics of a number of dihydroxynaphthyl-2H-benzotriazoles, their (meth)acryloyloxy derivatives and the corresponding polymers have been studied in a range of solvents of different polarity. It was shown that the formation of hydrogen bonds in these compounds strongly depends on the polarity of the solvent and an equilibrium exists between intramolecular and intermolecular hydrogenbonded states. The stability of the intramolecular hydrogen bond was determined quantitatively. The equilibrium between the intramolecular and the intermolecular hydrogen-bonded state of the molecule was strongly affected by the chemical structure of the naphthyl-2H-benzotriazole. The stability of the intramolecular hydrogen bond increased when electron-donating substituents were introduced into the benzotriazole or when the naphthyl-2-benzotriazole was fixed to a polymer backbone.     

邻氯乙酰氨基酚合成工艺的研究与表征

以氯乙酰氯为酰化剂,与邻氨基酚在溶剂—氯乙烷中合成了邻氯乙酰氨基酚,产率最高可达90%。分析了反应条件的改变对产物产率的影响。通过正交实验和规律性实验确定了最佳合成工艺:邻氨基酚、氯乙酰氯与溶剂的摩尔比为1∶2∶10,反应温度82°C,反应时间3 h。同时还对所合成的产物进行元素分析、质谱分析、红外光谱分析以及核磁共振氢谱分析,确定所合成的产物即是目的产物。     

2-(2-羟苯基)苯并咪唑的新颖合成和晶体结构

基于2-(2-1羟苯基)苯并咪唑(HPBI)在生物学、药理学及光电材料等方面的性质和应用意义,查阅大量文献,报道了配体HPBI新颖的合成方法,采用单晶衍射进行表征,并进行了该配体的晶体结构测定.结果表明,晶体属于单斜晶系,空间群P2(1),晶胞参数:α=3.8541(10)A°,b=2.2170(6)A°,c=5.86...     

苯并三氮唑乙酸乙酯的合成、热稳定性及几何空间结构优化研究

以苯并三氮唑为起始原料,经与氯乙酸反应制备得到苯并三氮唑乙酸,再与乙醇进行酯化反应合成得到苯并三氮唑乙酸乙酯。对产物苯并三氮唑乙酸乙酯的热稳定性研究显示苯并三氮唑乙酸乙酯在230℃后开始分解,具有良好的热稳定性;而升温速率对苯并三氮唑乙酸乙酯的起始分解温度会产生较大的影响。同时借助密度泛函对产物进行了结构优化。结果表明,苯并三氮唑乙酸乙酯分子电子密度分布较为均匀,优化后苯并三氮唑乙酸乙酯的HOMO和LUMO值分别为-0.213 528 e V和-0.072 481 e V。     

Gas-filled polymers. III. Mechanical behavior of polycarbonate and poly(vinyl chloride)

Gasification behavior and its effects on mechanical properties were determined for amorphous polycarbonate (PC) and poly(vinyl chloride) (PVC). Nitrogen-gasified PC and PVC exhibit interior regions containing gas bubbles surrounded by surface layers of void-free polymer, while in the helium-gasified polymers no gas bubbles could be observed. Scanning electron microscope (SEM) observations of the bubbles in nitrogengasified PC indicate that the bubble walls are smooth and featureless (in contrast to the diffuse walls with fibrils of polymer extending into the bubbles observed previously in gasified polyethylene). For both PC and PVC, neither the yield stress nor the elongation to fracture showed any appreciable variation between gasified and ungasified material. The lack of a significant effect of gas bubbles on the drawing behavior in these glassy polymers stands in contrast with the pronounced effect noted with semicrystalline polyethylene. The origin of this difference in behavior and its relation to the crystallization process in polyethylene are discussed.     

1-甲基-2-(2-羟基苯基)苯并咪唑新的合成法

采用Ｎ 甲基邻苯二胺与水杨酰氯以质量比为１∶１．６４在吡啶溶剂中回流,得到中间体及关环产物,分离出的中间体再以吡啶作溶剂,吡啶盐酸盐作催化剂回流关环。两步粗品合并经酒精纯化,得到精品１ 甲基 ２ （２ 羟苯基）苯并咪唑,总收率为５４％,比文献法提高４０％左右。结构经１ＨＮＭＲ、ＭＳ及元素分析验证,同时阐述了可能的催化机理。     

2-甲氧羰基-3-(4-羟苯基)丙酸甲酯的合成

4-苄氧基苯甲醛(Ⅱ)与丙二酸二甲酯脱水缩合,产生2-甲氧羰基-3-(4-羟苯基)丙烯酸甲酯(Ⅲ),收率为88%,化合物(Ⅲ)经过催化氢化,以95%的收率得到中间体2-甲氧羰基-3-(4-羟苯基)丙酸甲酯(Ⅰ),(Ⅰ)的合成总收率达到73.6%。产品的结构经过IR、ESI-MS1、H NMR确证。     

Photochemical reactions of polymers bearing chalcone residues

Photosensitive polymers based on pendent chalcone moieties were prepared directly by radical polymerization of vinyl-chalcone monomers. The monomers were synthesized by the esterification reactions of the hydroxyl groups of 4- and 4′-hydroxychalcones with methacryloyl chloride. The monomers (4- and 4′-(methacryloyloxy)chalcones) were polymerized to give the corresponding homo-and co-polymers containing different ratios of p-nitrophenyl methacrylate as photosensitizer group. Investigation of the photosensitivities of the chalcone polymers was carried out through study of the photochemical reactions on exposure to UV light and measuring the changes in UV spectra before and after irradiation. The results obtained from the disappearance rates of the C=C bonds indicate that the photoreactivities of the polymers are largely affected by the position of the attachment of the chalcone to the polymer backbone and by the concentration of the photosensitizer group.     

Synthesis and characterization of a fluorinated phthalazinone monomer 4-(2-fluoro-4-hydroxyphenyl)-phthalazin-1(2H)-one and its polymers from polycondensation reactions

As a category of high performance polymers having good solubility and distinguished thermal properties, poly(phthalazinone ether)s received much attention for their applications in engineering plastics and membrane materials. 2-(2-Fluoro-4-hydroxybenzoyl)-benzoic acid (FHBBA) synthesized from 3-fluorophenol and phthalic anhydride reacted with hydrazine hydrate to form 4-(2-fluoro-4-hydroxyphenyl)-phthlazin-1(2H)-one (FDHPZ). Four polymers were prepared from polycondensation reactions of FDHPZ with 4,4′-difluorobenzophenone, bis(4-chlorophenyl) sulfone, 1,4-bis(4-fluorobenzoyl)-benzene and perfluorobiphenyl, respectively. All polymers show good solubility in common aprotic solvents and have excellent thermal properties investigated by DSC and TGA. FTIR and NMR spectra of FDHPZ, FHBBA, and polymers from FDHPZ were studied. Refractive indices (n_TE) of films on silicon substrates were measured with a Prism Coupler. These polymers have potentials as materials for optical waveguides.     

普仑司特中间体2-乙酰胺基-6-乙酮基苯酚的合成

普伦司特是用于治疗哮喘病的白三烯受体拮抗剂类药物。文章研究其原始中间体2-乙酰胺基-6-乙酮基苯酚的合成,以2-氨基-4-氯苯酚为起始原料,通过酰化反应、重排反应、加氢反应制备2-乙酰胺基-6-乙酮基苯酚。最终产物经H1-NMR确定,HPLC含量99.3%。该工艺路线具有反应清洁、成本低廉、操作简单和易于工业化等优点。     

Photochemical reactions of high polymers. XIII. Photografting of methyl methacrylate onto the polymers bearing thiosulfate groups

Polymers bearing pendent thiosulfate groups, that is, sodium poly(vinyl benzyl thiosulfate) (PVBB) and the sodium salt of poly(vinyl hydrothiosulfatoacetate)(PV AcB), were prepared. The photograft polymerization of methyl methacrylate onto these polymers was carried out. The relationships between irradiation time and conversion, degree of grafting, and grafting efficiency were investigated in the photograft polymerization. It was ascertained that the pendent thiosulfate groups acted as effective initiators for the graft polymerization. From the number of endgroups in the homopolymer formed along with the graft polymer, the mechanism of the graft polymerization was discussed and it was verified that the graft polymerization was initiated by the thiyl radical formed by scission of the sulfur–sulfur bond of the pendent thiosulfate group. An unusually high degree of grafting and extremely rapid polymerization rate observed in the graft polymerization suggested the dual functions of thiosulfate-bearing polymer as initiator and emulsifier. It was found that addition of FeCl₂ to this polymerization system increased the rate of polymerization and the degree of grafting but decreased the grafting efficiency. The effect of FeCl₂ was interpreted by assumption of a photo-redox reaction between thiosulfate group and Fe²⁺.     

Functional water-insoluble polymers with ability to remove arsenic(V)

Three resins were synthesized through radical polymerization: poly[(ar-vinylbenzyl)trimethylammonium chloride] P(VBTA), poly[(ar-vinylbenzyl)trimethylammonium chloride-co-acryloylmorpholine] P(VBTA-co-AM), and poly[(2-acryloyloxy) ethyltrimethylammonium chloride-co-acryloylmorpholine]. The removal capacity for arsenic under different conditions was studied and compared with a commercial resin Amberlite IRA 400-Cl. The arsenic sorption capacity of the resins at the optimum pH showed the following order: Amberlite 95.5% (27.1 mg/g, 0.36 mmol/g), P(VBTA) 92.6% (16.3 mg/g, 0.22 mol/g), P(VBT-co-AM) 90.4% (21.5 mg/g, 0.29 mmol/g), and P(AETA-co-AM) 87.3% (21.7 mmg/g, 0.29 mmol/g).     

5-(2-羟基苯基)-10,15,20-三苯基卟啉及其衍生物的新法合成

在二甲苯溶液中,以氯乙酸作催化剂,在132℃及常压下合成了5－（2－羟基苯基）－10,15,20－三苯基卟啉等3种不对称卟啉。产物经红外光谱、紫外可见光谱等进行了表征。研究了反应时间、反应物比例、温度、浓度等对收率的影响,在优选的反应条件下,产物收率可达6．3％。     

Photochemical behavior of poly(organophosphazenes). XI. Photochemistry of poly[bis(4-benzylphenoxy) phosphazene]

In this paper we present results on the photolysis of poly[bis(4-benzylphenoxy)-phosphazene] in solution and in film, both in the presence and in the absence of molecular oxygen. Light irradiation of the polymer in oxygen-saturated CH₂Cl₂ solutions results in a remarkable degradation of the polyphosphazene, while in argon-purged solutions no appreciable variations of the polymer structure could be detected. The photolysis of poly[bis(4-benzylphenoxy)phosphazene] in films induces the cross-linking of the polymer regardless of the presence or the absence of molecular oxygen. The main process observed during the photochemistry both in solution and in the solid state of the polymer is the oxidation of the 4-benzylphenoxy group on the polyphosphazene, without involvement of the inorganic -P=N- backbone. The effect of temperature on the photolysis of the polyphosphazene substrate in film is also reported.