Polystyrene blends with poly

In another example, the cyclometalated iridium complex [Ir(ppy)2(4-vinylpyridine)Cl] has been attached via hydrosilation see Hydrosilation) to hydride-terminated poly(dimethylsiloxane) to produce a luminescent material. Evaluation of this material as a luminescent oxygen sensor revealed significantly improved sensitivity over dispersions of the original vinyl pyridine complex in poly(dimethylsiloxane). The luminescent material was blended with polystyrene to give a new sensor that exhibited increased sensitivity and maintained short response times to rapid changes in air pressure. 

Halogenated styrenes can form a number of copolymers, some used in blends with polystyrenes or other polymers. Examples of such copolymers are poly(o-chloro-styrene-co-p-chlorostyrene), polystyrene-co-poly(2-chlorostyrene) [14], poly(methyl acrylate-co-4-chlorostyrene), etc. A few studies on thermal behavior of these polymers are available [15, 16]. 

Oxidative coupling of phenols was first reported by Hay and coworkers in 1959" and has since been developed to produce commercially useful polymers. In these reactions the parent compound, phenol, has a potential functionality of four, that is the two ortho and the one para position of the aromatic ring and the phenolic group. Not surprisingly, the commercially useful polymers are made from substituted phenols in which the potential functionality is reduced to two. Of these phenols 2,6-dimethylphenol or orf/zo-xylenol has been developed to a commercial polymer, poly(2,6-dimethyl-1,4-phenylene oxide) (54). The General Electric Company sells this as a blend with polystyrene under the trade name Noryl. 

Wang H. L., Toppare L., and Fernandez J. E., Conducting polymer blends polythiophene and polypyrrole blends with polystyrene and poly (bisphenol A carbonate). 

Examples of such compatibilized systems that have been studied include EPDM/PMMA blends compatibilized with EPDM- -MMA, polypropylene/polyethylene blends with EPM or EPDM, polystyrene/nylon-6 blends with polystyrene/nylon-6 block copolymer, and poly(styrene-co-acrylonitrile)/poly(styrene-co-butadiene) blends with butadiene rubber/PMMA block copolymer. 

In order to meet increasing performance demands for electret applications, polymer electret blends are being explored. Lovera et al. have recently reported on tailored polymer electrets based on poly(2,6-dimethyl-l,4-phenylene ether) (PPE) and its blends with polystyrene (PS) [98]. They obtained good electret performance with neat PPE and showed that it could be improved by blending with PS. 

Lovera D, Ruckdaschel H, Goldel A, Behrendt N, Frese T, Sandler JKW, Altstadt B, Giesa R, Schmidt HW (2007) Tailored polymer electrets based on poly(2,6-dimethy 1-1,4-phenylene ether) and its blends with polystyrene. Eur Polym J 43 1195... 

Poly(2,6-dimethylphenylene ether) is amorphous and has a glass transition temperature of about 170°C. It is soluble in chlorinated hydrocarbons such as chloroform, carbon tetrachloride, as well as tetrachloroethane, and also in nitrobenzene and toluene. It is mainly used as a homogeneous blend with polystyrene (see Sect. 5.5). 

The photodegradation of poly(2,6-dimethyl-l,4-phenylene oxide) blends with polystyrene have also been reported [1722, 2129, 2130]. 

Figure 26.13 Surface segregation of cyclic poly(oxyethylene) (1.5kg/mol) from its blend with polystyrene by annealing in a high-humidity environment. Images of water drops are shown with then-contact angles above the as-spun-cast film (left) and after annealing (right).

The subject of IR and Raman-spectroscopic imaging has been covered comprehensively in a recent book [86]. In contrast to mapping, modern imaging techniques are based on the use of focal plane array detectors which allow the rapid characterization of multicomponent polymer samples such as blends of PMMA or poly(ethylacrylate) with polystyrene, or of poly(3-hydroxybutyrate) with poly(lactic acid). 

Omura, M., Tsukegi, T, Shirai, Y., and Nishida, H. (2007]. Selective depolymerization of poly-L-lactic acid into L,L-lactide from blends with polystyrene, Kobunshi Ronbunshu, 64,745-750 (in Japanese]. 

Examples of photothermoplasts include polyacrylates, polyacrylamides, polystyrenes, polycarbonates, and their copolymers (169). An especially well-re searched photothermoplast is poly(methyl methacrylate) (PMMA), which is blended with methyl methacrylate (MMA) or styrene as a monomer, and titanium-bis(cyclopentadienyl) as a photoinitiator (170). 

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