Polymer Photochemistry最新文献_第8页

Chemical effects of UV radiation on aqueous solutions of heparin-Ca salt 紫外线辐射对肝素-钙盐水溶液的化学影响

Polymer Photochemistry Pub Date : 1985-01-01 DOI: 10.1016/0144-2880(85)90044-2

Khurshid A. Khan, Riaz Farooq, Mohammad N. Iqbal

引用次数: 1

Photolysis of the azide group of linear polyester containing 3-azido-o-phthalic groups 含3-叠氮邻苯二甲酸基团的线性聚酯叠氮基团的光解

Polymer Photochemistry Pub Date : 1985-01-01 DOI: 10.1016/0144-2880(85)90017-X

Michalina Sierocka, Jerzy Paczkowski, Maria Toczek

{"title":"Photolysis of the azide group of linear polyester containing 3-azido-o-phthalic groups","authors":"Michalina Sierocka, Jerzy Paczkowski, Maria Toczek","doi":"10.1016/0144-2880(85)90017-X","DOIUrl":"10.1016/0144-2880(85)90017-X","url":null,"abstract":"<div>This paper presents the results of a study on the photolysis of the azide group in polyesters of 3-azido-ortho-phthalic acid and linear diols. It was stated that the apparent quantum yield of the azide group photolysis depends on the number of carbons separating the azide group and on the diol type, being different for diols with even and odd numbers of carbons. The formulated kinetic equation takes into account the effect of the initial concentration of the azide group on the rate of photolysis. Investigation of all the polyesters with a constant initial concentration of azide groups showed that the number of carbons in a diol does not affect the real quantum yield. However, it is affected by whether that number is odd or even. A value for the activation energy of photolysis was also determined. It amounts to Ea = 1·6 kcal mol−1 for polyesters with an odd number of carbons in the diol, and Ea = 0·34 kcal mol−1 for polyesters with an even number of carbons in the diol. It can be concluded from the research that the way of introducing the light-sensitive group into the polymer chain is decisive for the primary processes in the polymer under irradiation. The real quantum yield for the light-sensitive group attached to the main chain amounts to φ = 0·61. For the light-sensitive group introduced into the polymer chain this value is smaller; for polymers with an even number of carbons in the diol φ = 0·42−0·47 and for polymers with an odd number of carbons in the diol φ = 0·51−0·54.</div>","PeriodicalId":101036,"journal":{"name":"Polymer Photochemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0144-2880(85)90017-X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80460129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Radical reactivity of 2,2,6,6,-tetramethylpiperidine derivatives: A kinetic ESR study 2,2,6,6，-四甲基哌啶衍生物的自由基反应性:动力学ESR研究

Polymer Photochemistry Pub Date : 1985-01-01 DOI: 10.1016/0144-2880(85)90010-7

A. Faucitano, A. Buttafava, F. Martinotti, F. Gratani , P. Bortolus

引用次数: 1

Fading characteristics of some monoazo dyes on cellulose diacetate and polyamide films: Part I 一些单偶氮染料在双醋酸纤维素和聚酰胺薄膜上的褪色特性:第一部分

Polymer Photochemistry Pub Date : 1985-01-01 DOI: 10.1016/0144-2880(85)90033-8

F.M. Tera , L.A. Abdou , M.N. Michael , A. Hebeish

{"title":"Fading characteristics of some monoazo dyes on cellulose diacetate and polyamide films: Part I","authors":"F.M. Tera , L.A. Abdou , M.N. Michael , A. Hebeish","doi":"10.1016/0144-2880(85)90033-8","DOIUrl":"https://doi.org/10.1016/0144-2880(85)90033-8","url":null,"abstract":"<div>The absorption spectra of seven different monoazo dyes at different concentrations in water and in methanol as well as their absorption on cellulose diacetate (CDA) and polyamide (PA) films were examined. It was found that the extent of dye aggregation in methanol is greater than in water despite the higher dielectric constant of the latter, reflecting the anomalous behaviour of water. However, structural characteristics and concentration of the dye determine the state of dye molecules in water and methanol. Some of the dyes examined had greater tendency to aggregate while the others were probably present in monodispersed form. On the contrary, all the dyes used seem to have a strong tendency to aggregate on the CDA and PA films, indicating that involvement of the dye in an interaction with the substrate alters the structural characteristics of the dye and, therefore, its ability to aggregate. In accordance with this were the results of studies dealing with evaluation of the lightfastness of the same dyes on both films using daylight as well as a lightfastness tester for different exposure periods.</div>","PeriodicalId":101036,"journal":{"name":"Polymer Photochemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0144-2880(85)90033-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"137344096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Materials for microlithography: Radiation sensitive polymers 微光刻用材料:辐射敏感聚合物

Polymer Photochemistry Pub Date : 1985-01-01 DOI: 10.1016/0144-2880(85)90015-6

Norman S. Allen

引用次数: 0

Structure of crystalline polymers 结晶聚合物的结构

Polymer Photochemistry Pub Date : 1985-01-01 DOI: 10.1016/0144-2880(85)90021-1

A. Keller

引用次数: 0

Photochemical behaviour of thio-organotin stabilizers in polystyrene films 硫代有机锡稳定剂在聚苯乙烯薄膜中的光化学行为

Polymer Photochemistry Pub Date : 1985-01-01 DOI: 10.1016/0144-2880(85)90043-0

L. Jiráčková-Audouin, V. Bellenger, J. Verdu, D. Ranceze

引用次数: 2

Photo-induced polymerization of diethylene glycol diacrylate in the presence of poly(methyl methacrylate): 1—Polymerization without any photoinitiator 聚甲基丙烯酸甲酯存在下二丙烯酸二乙二醇的光诱导聚合:无光引发剂的1 -聚合

Polymer Photochemistry Pub Date : 1985-01-01 DOI: 10.1016/0144-2880(85)90039-9

D. Braun, R. Gehrisch

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引用次数: 3

The interaction of UV-absorbers with hindered piperidines in photostabilization of cis-1,4-polybutadiene 紫外光吸收剂与受阻哌替啶在顺式1,4-聚丁二烯光稳定中的相互作用

Polymer Photochemistry Pub Date : 1985-01-01 DOI: 10.1016/0144-2880(85)90011-9

Julia Lucki

引用次数: 4

Polymer photophysics and photochemistry 高分子光物理和光化学

Polymer Photochemistry Pub Date : 1985-01-01 DOI: 10.1016/0144-2880(85)90037-5

Norman S. Allen

引用次数: 0