Polystyrene chains, grafted, divinylbenzene

The new branched polystyrene chain may eventually terminate, cross-linked by reacting with another polystyrene chain or an immobilised divinylbenzene radical. Grafting is thus enhanced mainly through branching of the grafted polystyrene chain. This... 

At present, two major families of supports are used for SPPS. Polystyrene, lightly cross-linked (e.g., 1%) with divinylbenzene, was used in most of Merrifield s seminal work and is still very popular for SPPS and solid-phase organic synthesis [1,22]. Polyethylene glycol (PEG) grafted onto polystyrene has found widespread application. The PEG chain can either be covalently attached to the polystyrene support (PEG-PS) [23-25] or ethylene oxide polymerized onto the polystyrene (Tentagel and ArgoGel) [26,27]. 

Since the invention of SPPS, divinylbenzene-cross-linked polystyrene has been the predominant solid support used. There have been several alternatives developed along the way, with the most important advancement being the introduction of PEG, including PEG-grafted polystyrene resin [39, 40] and all-PEG-based resin (ChemMatrix) [41, 42]. PEG-based resins can produce crude products with better quality than the polystyrene resins, particularly in the case of difficult sequences [43]. This superiority is explained by the H-bond acceptor function of PEG which interrupts peptide inter-chain H-lxMiding, effectively inhibiting peptide chain aggregation [44],... 

This paper reports what we believe to be the first true IPN, i.e., no grafting between polymers and a single phase morphology (i.e., complete chain entanglement). In order to achieve this, pol3nners of known compatibility were used. Thus, IPN s, pseudo-IPN s (PDIPN s - only one polymer crosslinked), and linear blends of polystyrene (PS), and poly(2,6-dimethyl-l,4-phenylene oxide) (PPO) (whose compatibility has been reviewed elsewhere (14)) were prepared by the simultaneous interpenetrating network (SIN) technique. The polystyrene was crosslinked by incorporating divinylbenzene. Several methods have been reported to synthesize... 

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