Polystyrene-poly , single

Figure 9.17 Plot of log [i ]M versus retention volume for various polymers, showing how different systems are represented by a single calibration curve when data are represented in this manner. The polymers used include linear and branched polystyrene, poly(methyl methacrylate), poly(vinyl chloride), poly(phenyl siloxane), polybutadiene, and branched, block, and graft copolymers of styrene and methyl methacrylate. [From Z. Grubisec, P. Rempp, and H. Benoit, Polym. Lett. 5 753 (1967), used with permission of Wiley.]...

Few examples of the homogeneous diblock-incompatible homo-polymer behavior have been reported. One that has received considerable attention is the system polystyrene-poly-a-methylstyrene (2). Block copolymers of styrene and a-methylstyrene exhibit a single loss peak in dynamic experiments (2,3) and have been shown to be thermorheologi-cally simple (4) hence they are considered to be homogeneous. Mechanical properties data on these copolymers also has been used to validate interesting extensions of the molecular theories of polymer viscoelasticity (2,3,4). 

Fig. 6.1.4. Room temperature NMR of H in (top) poly(methyl phenyl siloxane), (middle), a polystyrene, poly(methyl phenyl siloxane) (PS-b-PMPS) block copolymer, and (bottom) polystyrene, under single-pulse excitation and magic-angle spinning (MAS). The PMPS is sufficiently mobile that in the pure polymer, and in some samples of the block copolymer, anisotropic molecular motion, when combined with MAS at 4 kHz severely attenuates both dipolar broadening and shielding anisotropy [31].

HAC Hachisuka, H., Sato, T., Tsujita, Y., Takizawa, A., and Kinoshita, T., CO2 gas sorption properties in single-phase and phase-separated polystyrene/poly(virtyl methyl ether) blends, Polym. J.,2, All, 1989. 

SMI Copolymer from styrene and maleimide SMM Styrene-methylmethacrylate copolymer SMMA Styrene methylmethacrylate sPhPS Syndiotactic poly(p-phenyl styrene) sPP Syndiotactic polypropylene sPS Syndiotactic polystyrene SSE Single-screw extruder TM Thio-rubber... 

Mokdad, A. Dubault, A. Monnerie, L. (1996) Sorption and Diffusion of Carbon Dioxide in Single-Phase Polystyrene/Poly(vinylmethylether) Blends, J. Polym. Sci. Polym. Phys., 34,2723-2730. 

Theta solvents have been established for poly(A -vinylcarbazole) in single solvents and for polystyrene in single and binary mixtures of 1-chlorodecane-3-methyl cyclohexanol. This has allowed Bazuaye and Huglin to determine the unperturbed dimensions as a function of solvent and temperature for polystyrene, from which it was observed that these were always higher in mixed solvent systems compared with the single theta solvent, and that preferential adsorption was not responsible. Friedrich and Prochazka carried this one step further and examined polystyrene in toluene-MEK—2-methylpropan-l-ol mixtures, i.e., two solvents and one precipitant. They showed that the composition at which the second virial coefficient was zero and at which [ /] attained the values comparable to a theta solvent, were not identical, but in this case preferential adsorption was used as an explanation. 

If the viscosity is not corrected for the concentration dependence of fb or Ug as in equations 29 and 30, it is found empirically that tjo can be represented as a single function of cM"/ over wide ranges of c and M. The exponent y is 0.68 for polyisobutylene in several different solvents and cellulose tributyrate in 1,2,3-trichloropropane for various solutions of polystyrene, poly(vinyl acetate), polyisobutylene, and other polymers it was found to range from 0.50 to 0.74. - When t]Q is proportional to M -, as frequently observed at sufficiently high values of M and c, and y = 0.68, tjq is then proportional to c . Fifth-power dependence on c has been observed over limited concentration ranges, but must be considered as an empirical approximation because it includes a concentration dependence of or Og which should preferably be described by a relation of the form of equation 12. 

Hermant MC, Klumperman B, Kyrylyuk AV, van der Schoot P, Koning CE (2009) Lowering the percolation threshold of single-walled carbon nanotubes using polystyrene/poly(3,4-ethylenedioxythiophene) poly(styrene sulfonate) blends. Soft Matter... 

Hermant M-C, van der Schoot P, Klumperman B, Koning CE (2010) Probing the cooperative nature of the conductive components in polystyrene/poly (3, 4-ethylenedioxythiophene) poly (styrene sulfonate) single-walled caibon nanotube composites. ACS Nano 4 2242... 

Several studies have concerned the microstnicture of lamellae in materials such as the block copolymers polystyrene-h/oc/r-poly-l-vinylpyridine [139] and polystyrene-h/oc/r-polybutadiene [140], as well as single crystals of poly-para-xylylene [139], and reveal features (such as intersecting lamellae (figure Bl.19.29)) that had not been previously observed. 

In 1954 the surface fluorination of polyethylene sheets by using a soHd CO2 cooled heat sink was patented (44). Later patents covered the fluorination of PVC (45) and polyethylene bottles (46). Studies of surface fluorination of polymer films have been reported (47). The fluorination of polyethylene powder was described (48) as a fiery intense reaction, which was finally controlled by dilution with an inert gas at reduced pressures. Direct fluorination of polymers was achieved in 1970 (8,49). More recently, surface fluorinations of poly(vinyl fluoride), polycarbonates, polystyrene, and poly(methyl methacrylate), and the surface fluorination of containers have been described (50,51). Partially fluorinated poly(ethylene terephthalate) and polyamides such as nylon have excellent soil release properties as well as high wettabiUty (52,53). The most advanced direct fluorination technology in the area of single-compound synthesis and synthesis of high performance fluids is currently practiced by 3M Co. of St. Paul, Minnesota, and by Exfluor Research Corp. of Austin, Texas. 

For some polymers, like polystyrene or poly(methyl methacrylate), narrow standards of known molar mass and small polydispersity are commercially available, which can be used for calibration. Unfortunately, such standards are not available for all polymers and then the obtained true molar masses of a specific polymer might differ by a factor of two from the value obtained by calibration with, e.g., polystyrene [30] (see Section 9.1). This problem can be resolved by the so-called universal calibration, which is based on the finding that the retention volume of a polymer is a single-valued function of the hydrodynamic volume of the polymer, irrespective of its chemical nature and... 

Most of the polymers are better known by their trivial names or trade names. Polymers prepared from single polymers are denoted by prefixing poly- to the name of the monomer, e.g., polyethylene, polypropylene, Polyacrylonitrile, polystyrene, etc. If the monomer has substituents or has a multi-worded name, the name of the monomer is enclosed in parenthesis after the prefix poly-, e.g., poly (methyl methacrylate), poly (vinyl alcohol), etc. Condensation polymers like that derived from ethylene glycol and terephthalic acid are named as poly (ethylene terephthalate). 

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