Poly-2,6-dimethylphenylene oxide

Membranes and Osmosis. Membranes based on PEI can be used for the dehydration of organic solvents such as 2-propanol, methyl ethyl ketone, and toluene (451), and for concentrating seawater (452—454). On exposure to ultrasound waves, aqueous PEI salt solutions and brominated poly(2,6-dimethylphenylene oxide) form stable emulsions from which it is possible to cast membranes in which submicrometer capsules of the salt solution ate embedded (455). The rate of release of the salt solution can be altered by surface—active substances. In membranes, PEI can act as a proton source in the generation of a photocurrent (456). The formation of a PEI coating on ion-exchange membranes modifies the transport properties and results in permanent selectivity of the membrane (457). The electrochemical testing of salts (458) is another possible appHcation of PEI. 

We have recently demonstrated the synthesis of poly(2,6-dimethylphenylene oxide) (PPO) via oxidative coupling in a C02 continuous phase (see Scheme 7) [76]. These reactions proceeded at 345 bar and either room temperature or... 

Of the diluents known to affect the dynamic relaxation behavior of polymers in the glassy state, water has so far received the greatest attention. Many polymers, which in the dry state are lacking any secondary relaxation process at temperatures from 77 to 273 K, e.g. poly(methyl methacrylate)135, polymethacrylamide136, cellulose and its derivatives137, collagen138, polysulfones139, poly(2,6-dimethylphenylene oxide)139, and others,... 

Kressler J, Kammer HW (1987) Miscibility behavior of poly(2,6-dimethylphenylene oxide) and poly(styrene-co-acrylonitrile). Acta Polym 38 600-602... 

A series of Japanese patent applications concerns addition of BPA/DC to poly(2,6-dimethylphenylene oxide) (PPO). Electroinsulating coatings with elevated heat resistance were obtained from PPO and BPA/DC [43]. As a rule, maleimide monomers are used together with BPA/DC. According to [44], the following reaction (Scheme 10) between BPA/DC and maleimide takes place ... 

Touring the last decade, catalyzed oxidative coupling has gained wide-spread interest as a novel and general polymerization method. Various polymer systems of scientific and commercial interest have been prepared by this novel technique. Such polymer systems include polyphenylene oxides) (9, 13, 25), of which poly(2,6-dimethylphenylene oxide) (PPO) is produced commercially polyphenylenes (21) poly-... 

FIGURE 10-65 The approximate glass transition temperatures of polyethylene, polydimethylsiloxane and poly(2.6-dimethylphenylene oxide). 

First experiments which focused on the variation of the conformational properties have been performed by Brown et al. [240], who studied the role of the interactions between matrix and brush polymers (enthalpy driven brush swelling, see Eq. 59). They used a series of polystyrene (PS)-poly(methyl methacrylate) (PMMA) symmetric diblock copolymers with different blocks labeled by deuterium, placed at the interface between PMMA and poly(2,6-dimethylphenylene oxide) (PPO) homopolymers. A double brush layer was created with PMMA blocks dangling into (neutral) PMMA homopolymer and PS blocks immersed in favorably interacting PPO melt (x=Xps/ppo<0)- The SIMS profiles obtained showed that the PS side of the block copolymer is stretched by at least a factor of 2 with respect to the PMMA side. 

Scalco, Huseby, and Blyler (8), Zosel (9), and Bergen and Morris (10). Prest and Porter (23) applied the same principle to homopolymer blends [poly (2,6-dimethylphenylene oxide)-polystyrene]. Recently some papers were published on triblock copolymers of styrene-butadiene-styrene and on their blends with polybutadiene (24, 25). Triblock copolymers can be considered heterophase material as the different constituent blocks are thermodynamically incompatible with each other, and, consequently, polystyrene domains are enclosed in polybutadiene (continuous matrix). The findings indicate that these systems are in general thermorheologically complex, so that the shift factor ar depends not only on temperature but also on time. These conclusions have been extrapolated to other two-phase systems. 

Polyacrylonitrile Poly(oxyethylene) Poly(2,6"dimethylphenylene oxide) Poly(ethylene terephthalate)... 

Oxidative coupling polymerization in SCCO2 has been demonstrated for the synthesis of poly(2,6-dimethylphenylene oxide) 27. The polymerization of 2,6-dimethylphenol in the presence of oxygen is conducted using CuBr as the catalyst, pyridine and a block copolymer of styrene and 1,1-dihydroperfluorooctyl acrylate (PS- -PFOA) as a stabilizer in SCCO2 (350 bar) at 40 C. The polymerization occurred via a dispersion process and produced the polymer in a 74% yield with high molecular weight (17 000) (Scheme 46). 

Poly(2,6-dimethylphenylene oxide) m 1.06 Hot water fittings, Sterilizable, medical, and surgical equipment... 

Air enriched with 40 % oxygen is necessary for medical treatment of asthma. For this kind of therapy, poly(4-methylpentene-l) and poly(2,6-dimethylphenylene oxide) are applied, for which the FO2 and o values are, 3.23xl0-9cm3(STP) cm/cm2-sec.cmHg, 4.1 1.58xl0-9cm3 (STP)-cm/cm2-sec-cmHg, 4.2, respectively. 

In another grafting to procedure, four polymers [PVDF, polysulfone (PSF), poly(2,6-dimethylphenylene oxide) and poly(phthalazinone ether ketone)] were chemically bonded to MWNTs using ozone-mediated process. Compared with pristine MWCNTs and PSF-modified MWCNTs, PVDF-modified MWCNTs were more efficient as additives that enhance the mechanical strength and electrical conductivity of PVDF. ... 

Poly(2,6-dimethylphenylene oxide), 3 Poly(2,6-dimethylphenylene oxide-m-styrene) 288-289... 

A perfectly mixed gas permeation module is separating carbon dioxide from nitrogen using a poly (2,6 - dimethylphenylene oxide) membrane. The feed is 20.0 mol% carbon dioxide and is at 25 °C. The module has 50.0 m of membrane. The module is operated with a retentate pressure of 5.5 atm and a permeate pressure of 1.01 atm. We desire a permeate that is 40.0 mol% carbon dioxide. The... 

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