Oligomeric polystyrene-poly

Additional examples of the application of the Flory EOS to polymer blends include polystyrene/poly(vinyl methyl ether) [15,20,21], oligomeric polystyrene/polybutadiene [22], ethylene-vinyl acetate/chlorinated polyethylene [23], poly(e-caprolactone)/PVC [24], poly-(ether sulfone)/poly(ethylene oxide) [25]. 

Off-line coupling of HPLC with FD-MS has been used by several authors [118-121] for the determination of oligomers, oligomeric antioxidants (such as poly-TMDQ), ozonation and vulcanisation products. Pausch [122] reported on rubbers, cyclic polyurethane oligomers, as well as on the determination of the molecular weight distribution (up to 5300 Da) and oligomer analysis of polystyrene. Also the components of an aniline-acetone resin were deduced from FD-MS molecular weights [122]. 

The majority of extreme data were received from the universities. It was evident that the switch-on, inject, switch-off approach was applied (likely by the students) without critical evaluation of data produced by the computers software. The least scattered M values were obtained in the industrial laboratories, in which evidently the skilled operators performed the measurements. Better data accuracy was obtained for polyamides [154] and for oligomeric polyepoxides [155] than for the unproblematic poly(dimethyl siloxane)s and even for the most simple polymer, polystyrene likely because only experts measured the latter difficult samples. 

The synthesis of poly(St-h-IB-h-St) triblock copolymer has been accomplished by many research groups [195-201]. The synthesis invariably involved sequential monomer addition using a difunctional initiator in conjunction with TiCU in a moderately polar solvent mixture at low (—70 to —90°C) temperatures. As already mentioned at the synthesis of poly(IB-f)-St) it is important to add St at 100% IB conversion. The selection of the solvent is also critical, coupled product that forms in intermolecular alkylation during St polymerization cannot be avoided when the solvent is a poor solvent (e.g., hexanes/MeCl 60/40 (v/v)) for polystyrene [202]. The formation of coupled product is slower in wBuCl or in MeChx/MeCl 60/40 (v/v) solvent mixture however, to obtain block copolymers essentially free of coupled product it is necessary to stop the polymerization of St before completion. Detailed morphological and physical properties of poly(St-h-IB-h-St) triblock copolymer have been reported [199, 203-206]. The two step sequential monomer addition method has also been employed to obtain poly(p-chlorostyrene-f)-IB- )-p-chlorostyrene) [68, 207], poly(indene-f)-IB- )-indene) [208], poly(p-tert-butylstyrene-f)-IB-h-p-tert-butylstyrene) [209], poly((indene-co-p-methylstyrene)-h-IB-f)-(indene-co-p-methylstyrene)) [210], poly(p-MeSt-f)-IB- )-p-MeSt) [202], and poly(styryl-POSS-i -IB-h-styryl-POSS) (POSS=polyhedral oligomeric silsequioxane) [211] copolymers. 

The acid-base Nafion composite membranes include blends of Nafion with polypyrrole (PPy) [98-104], polybenzimidazole (PBI) [105-107], poly (propyleneoxide) (PPO) [108, 109], polyfurfuryl alcohol (PFA) [110], poly(vinyl alcohol) (PVA) [111-115], sulfonated phenol-formaldehyde (sPF) [116], polyvinylidene fluoride (PVdF) [117-122], poly(p-phenylene vinylene) (PPV) [123], poly(vinyl pyrrolidone) (PVP) [124] polyanifine (PANI) [125-128], polyethylene (PE) [129], poly(ethylene-terephtalate) [130], sulfated p-cyclodextrin (sCD) [131], sulfonated poly(ether ether ketone) (sPEEK) [132-135], sulfonated poly(aryl ether ketone) (sPAEK) [136], poly(arylene ether sulfone) (PAES) [137], poly(vinylimidazole) (PVl) [138], poly(vinyl pyridine) (PVPy) [139], poly (tetrafluoroethylene) (PTFE) [140-142], poly(fluorinated ethylene-propylene) [143], sulfonated polyhedral oligomeric silsesquioxane (sPOSS) [144], poly (3,4-ethylenedioxythiophene) (PEDT) [145, 146], polyrotaxanes (PR) [147], purple membrane [148], sulfonated polystyrene (PSSA) [149, 150], polystyrene-b-poly(ethylene-ran-butylene)-bpolystyrene (SEES) [151], poly(2-acrylamido-2-methyl-l-propanesulphonic acid-co-l,6-hexanediol propoxylate diacrylate-co-ethyl methacrylate) (AMPS) [152], and chitosan [31]. A binary PVA/chitosan [153] and a ternary Nafion composite with PVA, polyimide (PI) and 8-trimethoxy silylpropyl glycerin ether-1,3,6-pyrenetrisulfonic acid (TSPS) has also been reported [154]. 

The experimental dependencies of 2p on the polymerization degree n have been obtained for a few oligomeric series. As found, the values increased with chain lengthening only up to a definite limit (a critical size close to Kuhn segment length), and then remained invariable [86, 88, 103]. Figure 19 shows such a plot for polystyrene (PS) and poly(a-methylstyrene) (PMS) a critieal size was about ten monomer units whereas Ak = 8 for these polymers. Moreover, the DMA(cj) experiments showed that the values of activation volume Vp practically coincided with the volumes of Kuhn segment Vk in several polymers (Table 1). 

Oligomerization on solid phase via the Sonogashira reaction has also been carried out by Hwang and Tour in the preparation of 24 tetrameric oligo(phenylene ethynylene)s [104], as well as by Diederich and coworkers [105,106], who prepared poly(triacetylene)-derived oligomers displaying high fluorescence intensities. Triazene linkers, to attach the scaffold to a polystyrene resin, were also employed in these two cases. On-bead homo-... 

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