Deuterated poly styrene

Figure 4-20. Mass average of the radius of gyration, Rg) w, of poly(styrene) as a function of the mass average molar mass m)w in carbon disulfide (O) cyclohexane ((P) and for deuterated poly(styrene) in the solid state ( ). Measurements at 35.4° C (after H. Benoit, D. Decker, and J. S. Higgins, C. Picot, J. P. Cotton, B. Farnoux, and G. Jannink).

Bruder and Brenn (1992) studied the spinodal decomposition in thin films of a blend of deuterated polystyrene (dPS) and poly(styrene-co-4-bromostyrene) (PBrxS) by TOF-ERDA. They examined the effect of different substrates on the decomposition process. In one series of experiments, a solution of the polymers in toluene was spread on a silicon wafer to form a film of thickness 550 nm which was then heated in vacuum at 180°C for various times. 

Constant-time imaging of H in solids has been applied in combination with MAS for line narrowing [Cor3, Cor4]. The images were recorded for a dynamically stressed poly(isoprene) phantom and of poly(butadiene) in two poly(butadiene)/poly(styrene) blends. Spectroscopic MAS imaging has also been tested on deuterated polymers to probe differences in molecular moblity from the lineshape of the rotary-echo envelope... 

Polymer (B) poly(styrene-6-butadiene) (completely deuterated) 2009WI2... 

The sodium salt of poly(styrene sulfonate) with a narrow molecular weight distribution (PSS77, GPC standard grade, Mw 77 kg/mol) has been obtained from Fluka. The powder was evacuated to remove any residual water content. The lithium salt of poly(styrene sulfonate) (30% wt in H2O, M , 75 kg/mol) and poly(styrene sulfonic acid) (18% wt in H2O, Mw 75 kg/mol) have been purchased from Aldrich. Both samples have been concentrated in a rotary evaporator and subsequently dried under vacuum. For all experiments a concentration of 5 mmol/1 (monomer) in deuterated solvents (D2O, CD3OD and their mixtures) has been used. 

Coupled HPLC-NMR measurements performed at slow flow rates in fully deuterated solvents and at room temperature have been made in several studies to determine polymer MWD, to analyze the end-groups and the copolymer chemical composition distribution, and to assess the chemical structure and the degree of polymerization of all oligomer species [176-178]. Gradient HPLC-NMR was used in the analysis of the chemical composition distribution of random poly (styrene-co-ethyl acrylate) copolymers [179]. A major drawback in most of these studies is that the measurements could only be conducted at ambient or slightly elevated temperatures, which limits the method applicability, since many polymers, such as polyethylene, polypropylene, and polyolefin copolymers are soluble at high temperatures. 

Using FRES and others techniques, Wang and Composto investigated wetting and phase separation in polymer blend films composed of deuterated poly(methyl methacrylate) (d-PMMA) and poly(styrene-raw-acrylonitrile) (h-SAN) at the critical concentration [176-180]. This blend is characterized by a lower critical solution temperature (LCST) behavior with Tlcst 160 °C and 0d-PMMA 0.5 [180]. In this... 

So far, the tacticity effect on polymer mixtures has been investigated mainly for the special systems where hydrogen bonding interaction is dominant, such as poly (vinyl chloride)/poly(methyl metacrylate) (PVC/PMMA) [1] or poly-styrene/poly(vinyl methyl ether) (PS/PVME) [2] mixtures. However, recently, there has been an interest in the effect of tacticity on polymer mixtures without specific interaction such as polyolefin/polyolefin [3] or polystyrene/ deuterated polystyrene mixtures [4,5]. 

Such hydrophilic macromonomers (DPn=7-9) were radically homopolymer-ized and copolymerized with styrene [78] using AIBN as an initiator at 60 °C in deuterated DMSO in order to follow the kinetics directly by NMR analysis. The macromonomer was found to be less reactive than styrene (rM=0.9 for the macromonomer and rs=1.3 for styrene). Polymerization led to amphiphilic graft copolymers with a polystyrene backbone and poly(vinyl alcohol) branches. The hydrophilic macromonomer was also used in emulsion polymerization and copolymerized onto seed polystyrene particles in order to incorporate it at the interface. 

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