Sorbents, synthetic polymer

SEC columns have become much more efficient since they were introduced in the late 1950s. The major factor for this has been the ability of synthetic polymer chemists to produce smaller particle sizes of column packing materials. The first sorbents were several 100 /mm wide in diameter (20), whereas modem columns are filled with particles in the range between 3 and 20 /mm, which caused an immense improvement in separation power. The major drawback... 

Because of the wide diversity in PUF manufacturing processes and likely contaminant chemistry, users are cautioned that sorbent quality control is more critical than with other synthetic polymers such as the Amberlite XAD series. Every effort should be made to procure PUF products consistently from the same manufacturer, preferably in each instance from the same production lot. Moreover, because of inconsistencies in manufacturing practices, first-time foam users should solicit the advice of other satisfied and experienced users in the selection of a sorbent supplier. 

Calcium oxide can absorb CO2 from pre-combustion systems. Natural sources of CaO, such as limestone, CaCOg, produce sorbents that lose reactivity relatively fast. Good CO2 sorbents were prepared with CaO precursors templated on three natural polysaccharides chitosan, agar and carrageenan, or three synthetic polymers poly(acrylic acid), poly(ethylene glycol) and poly(ethylene oxide-b-propylene oxide-b-ethylene oxide), respectively. Calcium oxide confined onto S5mthetic polymers exhibited better CO2 uptake activity and stability than CaO derived from commercial... 

Table I shows some of the characteristics of the commonly used sorbents. The charcoals are by far the most frequently used solid sorbent for organic vapors. Over 130 methods have been validated in our five-year study using coconut, petroleum, and synthetic charcoal. The other sorbents include silica gel, used primarily for amines, and porous polymers, used for substances not amenable to collection on charcoal or silica gel. Other researchers have used other sorbents, including Florisil, alumina, and molecular sieves.

Molecularly imprinted polymers have come to be recognised as antibody mimics since Mosbach and co-workers demonstrated the use of imprinted polymers for the sorbent assay of drugs [1], Not only in applications, but also in preparation principle, imprinted polymers can be regarded as antibody mimics the synthesis proceeds in a tailor-made fashion and the resultant polymers show specific binding for a given guest molecule. Also, imprinted polymers have many characteristic features as synthetic antibody mimics that contrast with natural antibodies. 

Polyethylene — A polymer (substance composed of very large molecules that are multiples of simpler chemical units) of the alkene, ethylene. Polyethylene is highly resistant to chemicals, and has low water absorption and good insulating properties and can be manufactured in a number of forms. Polyethylene also has high oleophilic properties and has been used successfully as a sorbent for cleaning up oil spills. (See also Alkenes, Oleophilic surface skimmers, Synthetic organic sorbents.)... 

Molecularly imprinted polymer (MIP) was synthetized using the herbicide 2,4,5-trichlorophenoxyacetic acid as a template, 4-vinylpyridine as an interacting monomer, ethylendimethacrylate as a cross-linker and a methanol-water mixture as a porogen Sorbents EnviCrom-P, Porapak, Oasis HLB, 30 mg. Oasis HLB, 60 mg. Oasis HLB, 200 mg... 

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