Polymers Arsenic Containing

Organometallic polymers - The chains of these polymers contain both carbon and metallic elements. They are also known as metal-containing polymers. Examples are antimony-containing polymers, arsenic-containing polymers, and so on. ... 

Although certain arsenic-containing polymers were obtainable by Method D, 1 (see Table IX-4), others were not. Polymers derived from dimethylarsinic acid had to be prepared by addition of the sodium salt of the acid to chromic nitrate in ethanol [Eq. (lX-42)] II) followed by reaction with sodium acetylacetonate. 

The synthesis and biological evaluation of arsenic-containing polymers is not new. Wang and Sheetz reported on the synthesis of 10-(alkenyloxy)phenoxarsine based monomers and polymers. The polymers and monomers were both active against a variety of fungal and bacterial agents (12). 

Pure o gen. Ethane, arsenic, black mass containing polymer of methylarsine. 

The technology of plasma formation of metal-containing polymers in the form of thin films dates from 1963, when Bradley and Hammes(15) prepared specimens from some forty different materials, and studied their electrical conductivities. Included in the study were organic compounds of iron, tin, titanium, mercury, selenium, and arsenic. The presence of a metal or transition element in the polymer did not lead to special electrical properties compared to the purely organic polymers studied. 

A connectivity of 1 is given for side chain metal-containing polymers as 1 in which the metal complex is connected via one bond to the main chain [11]. Additional examples for other connectivities are (Fig. 1-8) connectivity 2 in metal(yne)s 2 [12] connectivity 3 in arsenic(III) sulfide 3 connectivity 4 in a polymeric methyl rhenium oxide of the formula Ho.5[(CH3)o.92Re03] co 4 [13] or polymeric phthalocyanines 5 [14] connectivity 8 in lanthanide complexes of bis(tetradendate) Schiff base bridging ligands 6 [15]. 

Most of these polymers also have hydrophilic and hydrolysable ester and amide groups. Some organometallic polymers containing tin, antimony, Cu and arsenic, and polymer nanocomposites with metals like silver and copper also exhibit antimicrobial properties. 

Fishermen periodically recover chemical weapons and are burned through accidental exposure to sulphur mustard. This is because when sulphur mustard comes in contact with cold water a tarry substance forms around the exterior while the interior remains viscous over a period of many decades. The exterior consists mainly of precipitates derived from thickening agents (Fishermen then break open the crusty exteriors as they haul their catches into their boats and may then become exposed or contaminate their vessels as a result). The chemical composition of the tarry exterior is not well understood partly because it varies from case to case. Various polymer materials, such as alloprene and poly [methyl methacrylate] (PMMA), for example, were sometimes combined with sulphur mustard to lower its freezing temperature. Solvents such as chlorobenzene, have also been combined with sulphur mustard. Finally, sulphur mustard was often mixed with arsenic-containing agents, such as lewisite and diphenychloroarsine. 

Arsenic-containing antibacterial polymers have been prepared by the reaction of triphenylarsenic dichloride with 2,4-diamino-6-mercaptopyrimidine. 

In the arsenal of spectroscopic techniques, fluorescence measurements offer particular advantages, since they are sensitive and can be employed at relatively low concentrations of the luminescent species(4). Thus, we have initiated a study of the structures of ion-containing polymers using trivalent lanthanide ions as fluorescent probes. 

When sulphur is melted viscosity changes occur as the temperature is raised. These changes are due to the formation of long-chain polymers (in very pure sulphur, chains containing about 100 (X)0 atoms may be formed). The polymeric nature of molten sulphur can be recognised if molten sulphur is poured in a thin stream into cold water, when a plastic rubbery mass known as plastic sulphur is obtained. This is only slightly soluble in carbon disulphide, but on standing it loses its plasticity and reverts to the soluble rhombic form. If certain substances, for example iodine or oxides of arsenic, are incorporated into the plastic sulphur, the rubbery character can be preserved. 

Some of the polymers containing phosphorous, arsenic, selenium and tellurium are shown below ... 

In 1982, Soga et al. 256> showed that exposure of acetylene to AsFs at low temperatures leads to rapid polymerization (in our experience this reaction can be explosively violent). The product is a solid polymer which is heavily arsenic-doped and has a conductivity several orders of magnitude lower than a conventional sample of polyacetylene saturation-doped from the gas phase. Aldissi and Liepins 2S7) have adapted this reaction to the preparation of soluble polyacetylene by adopting AsF3 as the reaction solvent. They claim that polymerization of acetylene with AsF5 is very rapid, giving a polymer which is soluble in common solvents. However, elemental analysis shows that the polyacetylene formed contains about one As atom per 10 CH units and this is not removed on repeated reprecipitations. It seems likely that the As atoms form part of the chain backbone, conferring sufficient flexibility to allow dissolution. It is claimed that films of soluble polyacetylene can be doped but very little information has been published. 

Column studies with the nanoparticle base polymer used solutions containing either lOOpg L 1 of As(III) or As(V) (Cumbal and Sengupta, 2005). Even after more than 10000 bed volumes of water had passed through the system, arsenic concentrations in the treated water still remained below 10 pg L 1. The nanoparticle system releases less than 5 pgL-1 of iron into treated water and can be regenerated with an aqueous mixture of 2 % NaOH and 3 % NaCl (Cumbal and Sengupta, 2005). 

Silicon (Si) Silicon is a lustrous silvery gray material. Because silicon conducts electricity, but not as well as a metal, silicon is classified as a semimetal. Crystals of pure silicon that have been doped with arsenic or gallium are known as semiconductors and are used to fabricate computer chips. Silicone rubbers are polymers containing silicon, oxygen, and various hydrocarbon groups, and are used in applications ranging from sealants to breast implants. 

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