Chlorine natural

Fig. 6. Transmission IR spectra of chlorinated natural rubber, solvent cast from xylene, (a) Before heating, and (b) after heating at 170°C for 30 min [62].

Bromine and iodine are both prepared by oxidation of the corresponding halide ion with chlorine. Naturally occurring aqueous solutions of bromide ion with concentrations of up to 5000 ppm are found in Arkansas and in the Dead Sea in Israel. Iodide ion solutions of up to 100 ppm concentration are found in Oklahoma and Michigan. 

TG-FTIR Vulcanisation [32], ageing characterisation [39, 48], sulphur components in rubber [31], polyurethanes [37], polymer degradation mechanisms [30, 40, 41], identification of base polymers [36, 43, 44], thermal stability [46], grafted flame retardants [47], differentiation of EVA rubbers [45] and AN-NBR rubbers [36, 44], degradation of chlorinated natural rubber [42],... 

Tan, Y.Z., Liao, Z.J., Qian, Z.Z. etal. (2008) Two Ih-symmetry-breaking Ceo isomers stabilized by chlorination. Nature Materials, 7, 790-794. 

Palmer T. Y. (1976) Combustion sources of atmospheric chlorine. Nature 263, 44-46. 

Why chlorins Nature has broken the double bonds of ring IV, and, in bacteria, perhaps ring II. Is this significant ... 

Becher G., Carlberg G.E., Gjessing E.T., Hongslo J.K., Monarca S. (1985), High-performance size exclusion chromatography of chlorinated natural humic water and mutagenicity studies using the microscale fluctuation assay. Environ. Sci. Technol, 19, 422-426. 

As natural rubber is a product of nature, its properties are determined by the biochemical pathway by which the polymer is synthesized in the plant. In the case of natural rubber the polymerization process cannot be tailored like that of synthetic rubbers. The only option to modify natural rubber is after it has been harvested from the tree. The important modified forms of natural rubber include hydrogenated natural rubber, chlorinated natural rubber, hydro-halogenated natural rubber, cyclized natural rubber, depolymerised liquid natural rubber, resin modified natural rubber, poly(methyl methacrylate) grafted natural rubber, poly(styrene) grafted natural rubber, and epoxidized natural rubber [33,34]. Thermoplastic natural rubber prepared by blending natural rubber and PP is considered as a physically modified form of natural rubber. 

The main use of chlorinated natural rubber is for chemical and heat-resistant paints and coatings. It is also used in adhesive formulations, printing inks, paper coatings, and textile finishes. 

To avoid interferences, some modihcations in the extraction procedure have been proposed. The residue from the acetone extract can be dissolved with water and extracted with diethyl ether. Then the watery layer is discarded and the ether solution is collected. The solvent is removed and the residue suspended in 1% Tween 60 and injected i.p. into mice [55]. This modihcation eliminated interferences due to polar molecules, such as PSP toxins. Amnestic shellhsh poisoning (ASP) toxins, or salts, which are dissolved in the water. However, it can produce false negatives owing to the low solubility of YTX in diethyl ether [56,57], so the substitution of this solvent with ethyl acetate or dichloromethane has been proposed. Since the hrst one can generate emulsions when it is partitioned with water, dichloromethane was selected, although its high toxicity and chlorinated nature can likely be a problem for the safety of laboratories with many samples to analyze. 

Trehy, M. L. and T. I. Bieber. 1981. Detection, identification, and quantitative analysis of dihaloacetonitriles in chlorinated natural waters. In L. H. Keith, Ed. Advances in the Identification and Analysis of Organic Pollutants in Water. Vol. 

Toluene/boiling methanol Chlorinated natural rubber... 

Journal of Materials Science Letters 16, No.6, 15th March 1997, p.445-7 INFRARED SPECTROSCOPIC STUDIES OF THE INTERACTION BETWEEN NATURAL RUBBER AND CHLORINATED NATURAL RUBBER... 

Yang and co-workers [9,10] used high resolution Py-GC-MS and Fourier transform infrared spectrometry to study the structures of the chlorinated natural rubbers (CNR) prepared by two different processes. The results indicate that the fine structures of CNR prepared from latex and solution processes are different, whereas their basic structures are similar. The molecule of CNR from the latex process contains a few carboxyl and carbonyl groups. The rings on CNR molecular chains should be hexatomic rings. The optimum pyrolytic temperature for CNR is 445 °C, with an available range from 386-590 C. The characteristic pyrolytic products are cyclohexane homologues. 

Semi-synthetic polymers Chemically modifled natural polymers are classifled as semi-synthetic polymers. Some examples are epoxidised natural rubber (ENR), chlorinated natural rubber (Chlororub), nitrocellulose, carboxy methyl cellulose (CMC) and cellulose acetate. 

Ethylene, chlorinated Natural rubber, epoxidized Vinyl chloride Single Tg II was 50 mol% epoxidized Kaklas et al. (1991)... 

Chlorkautschuk Chlorinated natural rubber Bayer AG/Miles... 

Chlorinated polyethylene (CPE) n. Any polyethylene modified by simple chemical substitution of chlorine on the hnear backbone chain, CPEs range from rubbery amorphous elastomers at 35-40% Cl to hard, semicrystalline materials at 68-75% Cl. They are sometimes included with chlorinated natural and butyl rubbers under the term chlorinated rubbers. Certain CPEs are used as modifiers in PVC compounds to obtain better flexibihty and toughness, particularly low-temperature toughness, greater latitude in compounding, and ease of processing. 

Natural rubber in which about two-thirds of the hydrogen atoms have been replaced by chlorine atoms. The resin is formed by the reaction of rubber with chlorine at about 100° C in an inert solvent or as a latex. Unlike rubber, the resulting product is readily soluble and yields solutions of low viscosity. It is sold as white powder, fibers, or as blocks. Commercial products generally contain about 65% chlorine. It has good chemical resistance properties, however, it tends to cobweb when sprayed. Now mostly chlorinated polymers are used, as 1-butene, polyethylene, etc. It has adhesive properties and, because of its good fire resistance, is used in paints. (2) Chlorinated natural rubber. Manufactured by Bayer, Germany. 

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