Search results for "Butyl rubber"
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The influence of preservation method and time on theδ13C value of dissolved inorganic carbon in water samples
2009
The precise delta(13)C value of dissolved inorganic carbon (DIC) is important for various types of ecological studies. Without a preservation agent, microbial degradation of organic compounds continues in water samples and the delta(13)C value of DIC will become more depleted with time. HgCl(2) or acidification is often used to prevent microbial activity in water samples collected for carbon isotope ratio analyses of DIC. Mercury compounds are toxic and result in waste disposal problems. Other inhibiting agents or preservation methods are therefore needed. Two possible solutions are to use copper sulphate (CuSO(4)) as a preservative agent or to acidify water samples with phosphoric acid (H(…
Einfluss des polymerrückgrats auf eigenschaften von thermoplastischen elastomeren
1992
4-Urazoyl benzoic acid groups were statistically attached to various hydrocarbon elastomers, polar elastomers and partially crystalline polymers via a polymer-analogous reaction. DSC, FTIR, stress-strain experiments and dynamic-mechanical analysis were used to analyse whether these systems, analogous to functionalized polybutadienes, would form ordered supra-molecular structures of the polar side-groups that would lead to a thermoreversible crosslinking. While the structure formation is suppressed for elastomers with a large cross-sectional area of the chain (e.g. butyl rubber) or polar side-groups, (e.g. polychloroprene), the mechanical propertie can be controlled by balancing supermolecul…