Studies of the effects of molecular weight on the gamma irradiation degradation of poly [Methylmetacrylate] doped with p-N, N-dioxaloylaminobenze -N',N'-dioxaloylsulphonyloxamide and its cobalt [II] complex

Protection of some poly [methylmethacrylate] samples against gamma rays had been investigated in the absence and presence of p N,N-dioxaloylamjnobenzene-N', N' dioxaloylbenzenesul-phony-loxamide and its cobalt [II] complex. The pure PMMA [without additives], PMMA-ligand and PMMA-cobalt [II] complex composite samples were irradiated with gamma rays for different exposure doses [5, 15, 25, 35, 50, 75 and 100 kGy]. Viscosity average molecular weight [Mv-values] and thin layer chromatographic measurements were carded out after each irradiation dose. The maximum protection against gamma ray was found when 1% of the organic ligand or its cobalt [II] complex is used in the polymer matrix

Preparation and characterization of some phenol-Egyptian cotton fire wood resins

Optimum conditions have been determined for the synthesis of linear, soluble and easily mouldable condensation products from Egyptian cotton-fire wood [ECFW] using phenol as the condensation agent. Thin layer chromatographic techniques was used for characterizing the products during the kinetic studies. The data obtained on TLC [Rf- values] confirm the results of viscosity and drop-falling temperature measurements. Infrared spectroscopic studies on the phenolic resins prepared by condensation of phenol with furfural, xylose, glucose, holocellulose, resistant cellulose, pure soda lignin and [ECFW] powder were carried out. The IR spectrum of soda lignin phenol resin proves the presence of aliphatic methyl, methylene, methine and strong bonded OH groups. Drastic changes in band position and intensity are observed in the IR spectra of pure soda lignin and the respective phenolic resins, indicating the degradation processes could take place during the condensation reactions

Tetraoxalyl derivatives of some diamines suggested as secondary standards in permanganometric titrations

The reaction between urea, thiourea and p-phenylene diamine with aliphatic diprotic acids depends upon the molar ratio of the reactants and the experimental conditions employed. At a 1: 4 molar ratio [diamine: oxalic acid] under reflux condition, the tetrafunctional compounds are obtained. IR, UV and 1HNMR-spectroscopic studies were carried out for structure elucidation and characterization. Thermogravimetric analysis of the investigated compounds showed that 4 molecules of water of crystallization per each molecule of ligand were present. These ligands fulfill the requirements of ideal secondary standards for potassium permanganate. Alternatively, standardized potassium permanganate solutions are used for the volumetric microdetermination of as low as 0.1 mg of each of these ligands

Synthesis and characterization of iron complexes of tetraoxalyl para-phenylene diamine

A large number of inorganic compounds are known to contain metal ions of the same element in two different formal oxidation states, but few organometallic compounds of this type have been reported. Cowan et al. reported biferrocene Fe [II] Fe [III] picrate and Vertes and Suba examined the mixed iron states in formamide. The reaction between para phenylene diamine and aliphatic dibasic acids depends upon the molar ratio of the reactants and the experimental conditions employed. At a 1 : 4 molar ratio [para phenylene diamine: oxalic acid] under reflux condition, the tetrafunctional compounds is obtained. More recently tetrabasic [tetrasuccinyl urea] and tetraoxalyl urea were prepared]. The present work is mainly concerned with the reaction of para phenylene diamine with oxalic acid. The aim is to produce tetrafunctional product [tetraoxalyl para phenylene diamine][To p-phD] and to investigate the formation of Iron [II] and [III] complexes by Mossbauer and Infra-red spectroscopy