Ethylene dimethacrylate -base polymers

Reactive (unsaturated) epoxy resins (qv) are reaction products of multiple glycidyl ethers of phenoHc base polymer substrates with methacrylic, acryhc, or fumaric acids. Reactive (unsaturated) polyester resins are reaction products of glycols and diacids (aromatic, aUphatic, unsaturated) esterified with acryhc or methacrylic acids (see POLYESTERS,unsaturated). Reactive polyether resins are typically poly(ethylene glycol (600) dimethacrylate) or poly(ethylene glycol (400) diacrylate) (see PoLYETPiERs). 

It is of much interest to compare polymer monoliths with monolithic silica columns for practical purposes of column selection. Methacrylate-based polymer monoliths have been evaluated extensively in comparison with silica monoliths (Moravcova et al., 2004). The methacrylate-based capillary columns were prepared from butyl methacrylate, ethylene dimethacrylate, in a porogenic mixture of water, 1-propanol, and 1,4-butanediol, and compared with commercial silica particulate and monolithic columns (Chromolith Performance). 

In addition, the GMA/EDMA copolymer proved to serve as a basic unit for the fabrication of highly permeable bioreactors in capillary format. Trypsin immobilization after epoxide ring opening with diethylamine and attachment of glutaraldehyde is mentioned as the probably most prominent example [64], The immobilization of trypsin was also carried out using another class of reactive monolithic methacrylate polymer, which is based on 2-vinyl-4,4-dimethylazlactone, acrylamide, and ethylene dimethacrylate [65]. In contrast to GMA/EDMA, trypsin can directly be immobilized onto this kind of monolith, as the 2-vinyl-4,4-dimethylazlactone moieties smoothly react with weak nucleophils even at room temperature. 

A higher content of divinyl monomer directly translates into more cross-linked polymers in the early stages of the polymerization process and, therefore, lead to an earlier phase separation. This approach is predominandy used for the preparation of monoliths with very large surface areas [54]. Typical cross-linking monomers used today are ethylene dimethacrylate for methacrylate-based monoliths and divinylbenzene with styrenic monomers. 

The most widely used polymer monoliths are poly(styrene-co-divinylben-zene)-based monoliths and moderately polar monoliths based on methacrylic acid esters. While the first ones are strongly hydrophobic materials prepared by polymerization of styrene and its derivatives with divinylbenzene as the cross-linking agent [323,324], methacrylate-based monoliths are synthesized by polymerization of butyl methacrylate or other methacrylic acid esters with ethylene dimethacrylate as the cross-linking agent [325,326]. These types of monolithic media in capillary format are the main focus of a very detailed review by Urban and Jandera [327]. 

Frechet and coworkers explored the synthesis of polyester dendrons on solid support. These dendrons, based on 2,2-bis(hydroxymethyl)propanoic acid monomers, were assembled up to the fourth generation on poly(2-hydroxyethyl methacrylate-co-ethylene dimethacrylate) resin and decorated with chiral proline derivatives (Scheme 15.15). T vo methods for preparation of these materials were reported. The solid-phase divergent approach yielded polymer with higher loading but a less precise architecture than the second approach. The second approach, the divergent synthesis of the dendrons in solution, followed by the focal point deprotection and then attachment to the solid support, led to well-defined structures on the polymer, but relatively low loading. 

Ethylene glycol dimethacrylate (EDMA)-methacrylic acid (MAA) copolymer-based imprinted polymer particles were mixed with poly(vinyl chloride) in THF, and the solution was then spread on the electrode of the QCM by spin coating. After evaporation of the THF, the polymer particles were immobilized on the surface. A phenobarbital-imprinted QCM sensor prepared in this way worked in ethanol [1], while epinephrine- and caffeine-imprinted QCMs worked in buffer solutions (pH 6.0 and pH 8.0, respectively) [2, 3],... 

A nucleotide base-imprinted polymer membrane has been reported in which methacrylic acid was used as a functional monomer for the imprinting of an adenine derivative, 9-ethyladenine [41], A free-standing film was prepared by polymerizing a DMF solution containing methacrylic acid and ethylene glycol dimethacrylate on a silanized glass slide at 65-70 °C under nitrogen atmosphere. 

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