Poly 2,6-diphenyl-1,4-phenylene

The intramolecular flexibilities of poly(1,4-phenylene oxide), polyi2,6-dimethyl-1,4-phenylene oxide), poly(2-methyl-6-phenyl-1,4-phenylene oxide), and poly 2,6-diphenyl-1,4-phenylene oxide) are evaluated through estimation of the resistance to rotation about the Cj 4—0 bonds in their backbones. A 6-12 potential is used to account for the van der Waals interactions between nonbonded atoms and groups encountered during the backbone rotations, while the twofold intrinsic potential to rotation about the C14—0 bonds resulting from the -electron delocalization is also included. 

Sulfonation has been used to change some characteristics of blends. Poly(2,6-diphenyl-1,4-phenylene oxide) and polystyrene are immiscible. However, when the polymers were functionalized by sulfonation, even though they remained immiscible when blended, the functionalization increased interfacial interactions and resulted in improved properties (65). In the case of DMPPO and poly(ethyl acrylate) the originally immiscible blends showed increased miscibility with sulfonation (66). 

Chalk and co-workers (99, 100), using the same complex, reported the lithiation of poly(2,6-dimethyl-1,4-phenylene) ether and poly(2,6-diphenyl-1,4-phenylene) ether under various metalation conditions. They achieved a catalyst efficiency of only 17%, as determined by the lithium content in the polymers. 

Poly (2,6-diphenyl-1, 4-phenylene oxide) Poly(ethylene terephthalate)... 

Separation properties of poly-2,6-dimethyl-1,4-phenylene oxide (p-DMePO) and poly-2,6-diphenyl-1,4-phenylene oxide (p-DPhPO), as well as chemically modified p-DMePO have been studied by a number of researchers for the purpose of using these polymers in gas separation and pervaporation processes [18,68,71]. p-DMePO/p-DPhPO copolymers offer a number of advantages compared to homopolymers better mechanical properties, higher resistance to oxidants and radiation, which is why these copolymers have also been studied rather closely [18,71]. Investigation of p-DMePO and p-DPhPO homopolymers has... 

Ballard Advanced Materials (BAM) ionomers are sulfonated copolymers of trifluorostyrene and substimted trifluorostyrene monomers. BAM, a subsidiary of Ballard Power Systems, investigated the conducting polymers based on polyphenylquinoxaline (PPQ). These can be sulfonated in a wide range and were referred to as BAMIG (Ballard first generation) membranes, but these membranes were found to have short durability. To overcome this problem, BAM developed a second generation of advanced membranes based on two distinct material types. The first material type consisted of a series of sulfonated poly(2,6-diphenyl 1,4-phenylene oxide). The second material type consisted of a series of sulfonated poly(arylether sulfone). But the durability of these membranes was also insufficient. Since the durability of previous membranes was limited, Ballard produced a novel family of sulfonated membranes based on a,p,p-ttifluorostyrene monomers and a series of substituted ttifluoro-comonomers... 

Poly(2,6-diphenyl-1,4-phenylene oxide) (P30) is obtained from the polymerization of 2,6-dimethylphenol. In comparison to 2,6-dimethylphenol, the oxidation potential of 2,6-diphenylphenol is higher. Higher temperatures of polymerization are necessary. ... 

Polymers cannot be purified by recrystallization, since many polymers do not crystallize, and, in the case of those that do, impurities may be included during crystallization. For example, centimeter-long crystals that still contain 30% solvent are obtained by evaporation of dilute solutions of poly(2,6-diphenyl-1,4-phenylene ether). Even the protein single crystals contain large amounts of water. 

Poly(2,6-diphenyl- 1,4-phenylene oxide)" [24938-68-9] CgHs CgHs 230 (12)... 

The oxidative polymerization reaction was found to be a general reaction and linear high molecular weight polymers and diphenoquinones were prepared from other 2,6-dialkylphenols. If the substituents are bulky, e.g. a t-butyl group, only the diphenoquinone is formed. We were also able to synthesize high molecular weight poly (2,6-diphenyl-1,4-phenylene oxide) (P3O, 5) from 2,6-diphenylphenol 4. (Scheme 2)... 

Wrasidlo, W., Transitions and Relaxations in Poly(2,6-diphenyl 1,4-phenylene ether). Macromolecules, 1971. 4 p. 642-8. 

A relatively new representative of the polyphenylene ethers is poly-2, 6-diphenyl-1, 4-phenylene oxide, a homologue of poly-2,6-dimethyl-l,4-phenylene oxide with the methyl groups in the positions 2 and 6 of the backbone phenylene ring replaced by phenyls. This material, hereafter... 

Table 2. Permeability coefficients of poly-2,6-diphenyl-1,4-phenylene oxide films...

The homopolymers - poly-2, 6-dimethyl-1, 4-phenylene oxide and and poly-2, 6-diphenyl-1, 4-phenylene oxide - exist in the semicrystalline form, while the copolymers are completely amorphous. Both crystalline and... 

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