Polystyrene networks synthesis

The fact that macroporous, highly cross-linked polystyrene does not swell makes this support particularly interesting for continuous-flow synthesis in columns. This support has also been successfully used as an alternative to CPG for the solid-phase synthesis of oligonucleotides [90,91]. Furthermore, because reagents do not need to penetrate into the polystyrene network, enzyme-mediated reactions should also proceed smoothly on macroporous polystyrene [85]. 

SYNTHESIS OF MACRONET ISOPOROUS AND HYPERCROSSLINKED POLYSTYRENE NETWORKS... 

Synthesis conditions of macronet isoporous and hypercrosslinked polystyrene networks... 

Finally, it could be mentioned here that the basic idea of hypercrosslinked network synthesis was also appfied to the preparation of porous fibrous sorbents. Liu et al. [278] have suggested grafting of styrene— DVB copolymer to the surface of polypropylene fibers, followed by the post-crosslinking of the grafted copolymer with 4,4 -bis-(chloromethyl)-diphenyl to 100% degree of crosshnking in a mixture of ethylene dichloride, nitrobenzene, and cyclohexane. After being coated with several successive layers of such hypercrosslinked polystyrene, the final fiber material... 

Chapters 7-9 form the second part and describe the hypercrosshnked polystyrene networks. These chapters cover in detail the basic principles of the formation of hypercrosshnked polymers, the synthesis of hypercrosshnked networks and also the properties and morphology of the polystyrene networks. Characterization techniques such as electron microscopy and X ray scattering are also covered. Hypercrosshnked polymers like polysuhbne, polyarylates or polyanilines among others are also reported on as a novel class of polymeric materials. 

Site Isolation Organic Synthesis in Polystyrene Networks... 

N. Devia-Manjarres, G. Yenwo, J. Pulido, J. A. Manson, A. Conde, and L. H. Sperling, Castor Oil Based Interpenetrating Polymer Networks Synthesis and Properties of Emulsion-Polymerized Products, AIChE Symp. Ser. 73(170), 133 (1977). Sulfur-vul-canized/polystyrene IPN. Impact resistance. Sodium ricinoleate as emulsifying agent for polymerization of polystyrene. 

N. Devia, J. A. Manson, L. H. Sperling, and A. Conde, Simultaneous Interpenetrating Networks Based on Castor Oil Elastomers and Polystyrene. 2. Synthesis and Systems Characteristics, Macromolecules 12(3), 360 (1979). Synthesis and Processing of castor oil-polyester/PS SINs. Rubber-toughened plastics and reinforced elastomers. 

By a method similar to isoporous polystyrene synthesis, poly(4-vinylpyridine) has been cross-linked with dibromoalkanes to give insoluble networks containing pyri-dinium ions (26)113). 

The synthesis and characterization of these ABA block copolymers of styrene and dienes have been described elsewhere (JO, 11). Since the polystyrene end blocks aggregate into glassy domains which act as network junctions, the elastic center blocks must virtually represent the network chains/ The polystyrene domains should also act as a finely divided filler. Hence it might be expected that the mechanical properties of these materials could depend on the two basic parameters polystyrene content and length of center block ( molecular weight between crosslinks ). 

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