Poly dimethyl ether

Alkylated phenol derivatives are used as raw materials for the production of resins, novolaks (alcohol-soluble resins of the phenol—formaldehyde type), herbicides, insecticides, antioxidants, and other chemicals. The synthesis of 2,6-xylenol [576-26-1] h.a.s become commercially important since PPO resin, poly(2,6-dimethyl phenylene oxide), an engineering thermoplastic, was developed (114,115). The demand for (9-cresol and 2,6-xylenol (2,6-dimethylphenol) increased further in the 1980s along with the growing use of epoxy cresol novolak (ECN) in the electronics industries and poly(phenylene ether) resin in the automobile industries. The ECN is derived from o-cresol, and poly(phenylene ether) resin is derived from 2,6-xylenol. 

Correct IUPAC nomenclature poly(oxy-2,6-dimethyl-l,4-pheylene), PPO, poly(oxy-l,4-phenylenesulfonyl-l, 4 -phenyleneoxy-l",4 phenylene (1 -methylethylidene)-l , 4" -phenylene), poly(arylene ether sulfone), and poly(oxy-(2-hydroxytrimethylene) oxy-l,4-phenylene(l -methylethylidene)-l, 4 -phenylene), phenoxy resin. 

These materials are segmented copolyether esters formed by the melt transesterification of dimethyl terephthalate, poly(tetramethylene ether) glycol and 1,4-butane diol. As with the thermoplastic polyurethanes, one can describe a hard segment and a soft segment, the hard segments forming crystalline areas which act as pseudocrosslinks . 

Figure 5. UV spectra for (a) 4,4 -diazidodiphenyl methane in a diethylene glycol dimethyl ether (7.2xl0 5 mole/1) and (b) poly(styrene-co-maleic acid half ester) (1.0 micron film thickness).

The electrolysis apparatus for the polymerization is illustrated in Figure 2, which is characterized by a single cell without a partition membrane between the electrodes. In poor solvents of poly(phenyleneoxide) s such as methanol and acetonitrile, the polymer was deposited on the electrode, i.e. passivation of the electrode occured. Dichlo-romethane, nitrobenzene, and hydroquinone dimethyl ether were selected as the solvents because both the polymer and a supporting electrolyte dissolved in them and they were relatively stable under electrolysis conditions. 

Poly(aryl ether sulfone) Dimethyl sulfoxide, DMF Alcohol, ether... 

Sinclair-Koppers Co. Lexan 125 bisphenol A polycarbonate from General Electric Co. Polysulfone aromatic poly(sulfone-ether) from Union Carbide Corp. and PPO poly(2,6-dimethyl-p-phenylene oxide) from General Electric Co. 

Stable dialkyl ether poly(hydrogen fluoride) complexes (R20-[HF]n, R = Me, Et, n-Pr) have recently been developed by Prakash, Olah, and colleagues.33 DFT calculations suggest a cyclic poly(hydrogen fluoride) bridged structure. Dimethyl ether-5 HF (DMEPHF) was shown to be a convenient and effective fluorinating agent (see Section 5.10.1). 

Stable dialkyl ether poly(hydrogen fluoride) complexes have been shown to be convenient and effective fluorinating agents.553 Various open-chain and cyclic alkenes undergo hydrofluorination with dimethyl ether-5 HF (DMEPHF) atroom temperature to furnish the corresponding fluoro derivatives in high yields (73-94%) with excellent selectivities. The fluorination of secondary and tertiary alcohols exhibit similar features. Bromofluorination of alkenes can also carried out with DMEPHF in combination with /V-bromosuccinimide. The homologous diethyl ether and dipropyl ether complexes are also suitable for fluorinations. 

INCLUSION OF POLY (ETHYLENE GLYCOLjS AND THEIR DIMETHYL ETHERS... 

Table 3 Inclusion of poly(ethylene glycol) dimethyl ethers by the dipeptide (2).

The selectivity of the Complex Formation is a very interesting subject, y - Cyclodextrin, (y - CD) has been found to form inclusion complexes with poly (methyl vinyl ether) (PMVE), poly(ethyl vinyl ether) (PEVE), and poly(n- propyl vinyl ether) (PnPVE) of various molecular weights to give stoichiometric compounds in crystalline states. However, a- cyclodextrin (a - CD) and (3 - Cyclodextrin ((3- CD) did not form complexes with poly (alkyl vinyl ether)s of any molecular weight, y -CD did not form complexes with the low molecular weight analogs, such as diethyl ether and trimethylene glycol dimethyl ether. 

CO2-PEG system is also effective for the scandium-catalyzed aldol reactions, and poly(ethylene glycol) dimethyl ether (PEG(OMe)2, MW = 500) is more effective than PEG (Scheme 3.12) [57]. Emulsions in C02-PEG(0Me)2 medium are observed when the concentration of the additive is 1 g/L. Not only benzal-dehyde but also substituted aromatics, aliphatic, and a, /]-unsaturated aldehydes react smoothly, and various silicon enolates derived from a ketones, esters, and thioesters also react well to afford the corresponding aldol adducts in high yields. 

Synthesis of the 2G-based copolymer can be somewhat more difficult than synthesis of the analogous 4G-based copolymer. If the ethylene glycol and dimethyl terephthalate monomers are prereacted to form bis (2-hydroxy ethyl) terephthalate, and this product is then copolymerized with poly(tetramethylene ether) glycol to form the block copolymer using tetrabutyl titanate as the transesterification catalyst, the reaction proceeds readily and copolymer of high inherent viscosity is easily obtained. If the ethylene glycol monomer is not prereacted and tetrabutyl titanate is again used as the transesterification catalyst, the copolymerization proceeds more slowly and a block copolymer of lower inherent viscosity is usually obtained. 

PC = polycarbonate PET = polyethylene terephthalate) PEEK = poly (aryl-ether-ether-ketone) PO = poly(oxy-1,4-pheny lene) PPS = poly (thio-l,4-phenylene) PPO = poly(oxy-2,6-dimethyl-l,4-phenylene) PEN = poly(ethylene-2,6-naphthalenedicarboxylate) PBT = poly... 

PB PBI PBMA PBO PBT(H) PBTP PC PCHMA PCTFE PDAP PDMS PE PEHD PELD PEMD PEC PEEK PEG PEI PEK PEN PEO PES PET PF PI PIB PMA PMMA PMI PMP POB POM PP PPE PPP PPPE PPQ PPS PPSU PS PSU PTFE PTMT PU PUR Poly(n.butylene) Poly(benzimidazole) Poly(n.butyl methacrylate) Poly(benzoxazole) Poly(benzthiazole) Poly(butylene glycol terephthalate) Polycarbonate Poly(cyclohexyl methacrylate) Poly(chloro-trifluoro ethylene) Poly(diallyl phthalate) Poly(dimethyl siloxane) Polyethylene High density polyethylene Low density polyethylene Medium density polyethylene Chlorinated polyethylene Poly-ether-ether ketone poly(ethylene glycol) Poly-ether-imide Poly-ether ketone Poly(ethylene-2,6-naphthalene dicarboxylate) Poly(ethylene oxide) Poly-ether sulfone Poly(ethylene terephthalate) Phenol formaldehyde resin Polyimide Polyisobutylene Poly(methyl acrylate) Poly(methyl methacrylate) Poly(methacryl imide) Poly(methylpentene) Poly(hydroxy-benzoate) Polyoxymethylene = polyacetal = polyformaldehyde Polypropylene Poly (2,6-dimethyl-l,4-phenylene ether) = Poly(phenylene oxide) Polyp araphenylene Poly(2,6-diphenyl-l,4-phenylene ether) Poly(phenyl quinoxaline) Polyphenylene sulfide, polysulfide Polyphenylene sulfone Polystyrene Polysulfone Poly(tetrafluoroethylene) Poly(tetramethylene terephthalate) Polyurethane Polyurethane rubber... 

Phase behavior studies with poly(ethylene-co-methyl acrylate), poly (ethylene-co-butyl acrylate), poly(ethylene-co-acrylic add), and poly(ethylene-co-methacrylic acid) were performed in the normal alkanes, their olefinic analogs, dimethyl ether, chlorodifluoromethane, and carbon dioxide up to 250 °C and 2,700 bar. The backbone architecture of the copolymers as well as the solvent quality greatly influences the solution behavior in supercritical fluids. The effect of cosolvent was also studied using dimethyl ether and ethanol as cosolvent in butane at varying concentrations of cosolvent, exhibiting that the cosolvent effect diminishes with increasing cosolvent concentrations. 

PPG PPGDE PPMA PpMOS PpMS polylpropylene glycol) polylpropylene glycol dimethyl ether) polyin-propyl methacrylate) poly(p-methoxystyrene) poly(p-methylstyrene)... 

POLY(OXY-l, 2-ETHANEDIYL), a-METHYL-CO-METHOXY-(9CI) see DOMIOO POLYOXYETHYLENE (75) see PJT750 POLYOXYETHYLENE 1500 see PJT500 POLYOXYETHYLENE DIMETHYL ETHER see DOMIOO... 

---