Polyether glycol

To produce a spandex fiber by reaction spinning, a 1000—3500 molecular weight polyester or polyether glycol reacts with a diisocyanate at a molar ratio of about 1 2. The viscosity of this isocyanate-terrninated prepolymer may be adjusted by adding small amounts of an inert solvent, and then extmded into a coagulating bath that contains a diamine so that filament and polymer formation occur simultaneously. Reactions are completed as the filaments are cured and solvent evaporated on a belt dryer. After appHcation of a finish, the fibers are wound on tubes or bobbins and rewound if necessary to reduce interfiber cohesion. 

Long-chain aUphatic acids such as adipic acid (qv) [124-04-9] are generally used to improve flexibiUty and enhance impact properties, demonstrating subtle improvements over resins modified with the ether glycols (diethylene glycol) and polyether glycols (polypropylene glycol) (see PoLYETHERs). 

THE can be polymerized by many strongly acidic catalysts, but not all of them produce the requked bitimctional polyether glycol with a minimum of by-products. Several large-scale commercial polymerization processes are based on fluorosulfonic acid, HESO, catalysis, which meets all these requkements. The catalyst is added to THE at low temperatures and an exothermic polymerization occurs readily. The polymerization products are poly(tetramethylene ether) chains with sulfate ester groups (8). 

Terathane Polyether Glycols, Material Safety and Data Sheet, E. I. du Pont de Nemours Co., Inc., Wilmington, Del., 1991. 

G. E. Manser, "Nitrate Ester Polyether Glycol Prepolymer," JANNAF Propulsion Committee Meeting, New Orleans, La., Chemical Information Agency, John Hopkins University, Baltimore, Md., 1984. 

Commercial thermoplastic polyesters are synthesized in a similar way by the reaction of a relatively high molecular-weight polyether glycol with butanediol and dimethyl terephthalate (14,15). The polyether chain becomes the soft segment in the final product, whereas the terephthaUc acid—butanediol copolymer forms the hard crystalline domains. 

Coupling reactions of diisocyanates with polyether glycols or polyesters lead to prepare macrobisperoxides [11,12] ... 

The various POPs and POEs are all PAGs, and various derivatives are available. They are also called polyoxyalkylenes poly glycols or polyether glycols. 

Polydiallyl-dimethylammonium chloride polymers Polyelectrolytes Polyether glycols Polyethersulfone RO membranes Polyethoxylates, as adjuncts Polyethylene glycol... 

The same dibutyltin compounds are used in the industrial manufacture of poly(urethane) foams, the first step in which involves the addition of a polyether glycol to 2,4-diisocyanotoluene, to produce the urethane prepolymer having isocyanate end-groups. 

Hazards Associated with Organic Chemical Manufacturing Polymerization Processes for Polyvinyl Chloride and Polyether Glycols, Mitre Corp., McLean, VA, Report No. MTR-79W00364-04, May 1979. 

D. L (1981) A new polymerization technique for preparing low molecular weight polyether glycols. JANNAF Propulsion Meeting, New Orleans, Louisiana, USA, May 26-28,1981, pp. 29-38. 

Other important tests are for acid and alkalinity number and for water content (266), because water content and alkalinity of the polyether glycol can influence the reaction with isocyanates. The standard ASTM test for acid and alkalinity number, ASTM D4662 (267), is not sensitive enough for the low acidity and alkalinity numbers of PTMEG, and special methods have been developed. A useful alkalinity number (AN) has been defined as milliequivalents KOH per 30 kg of PTMEG, as titrated in methanol solution with 0.005 N HC1 (268). Other useful nonstandard tests are for heavy metals, sulfated ash, and peroxide. The peroxides formed initially in oxidations are quickly transformed into carbonyl groups, which are detectable by infrared spectroscopy. On oxidation, a small C—O peak develops at 1726 cm-1 and can be detected in thick (0.5-mm) films. A relative ratio of this peak against an internal standard peak at 2075 C—O is sometimes defined as the carbonyl ratio. 

Furukawa et al. 67) have synthesised block copolymers with polystyrene and polyether segments from azo group-containing prepolymers, which were prepared by reaction of a low-molar-mass azobis-alcohol with polyether glycols containing isocyanate endgroups ... 

Amorphous Polyether Glycols Based on bis-Substituted Oxetane and Tetrahydrofuran Monomers... 

Random Urea-Urethane Copolymer of Polyether Glycol,... 

Nylon block copolymers were previously synthesized from the anionic polymerization of caprolactam in the presence of polyurethane prepolymers. (11) The prepolymers, prepared from the reaction of diisocyanates with polyether glycols, contained Isocyanate end groups which initiated caprolactam polymerization. Sodium caprolactam was used to catalyze the reaction. This copolymer system is the basis for some current areas of nylon 6 RIM research. (12) NYRIM nylon block copolymers are formed from stoichiometric mixtures of polymeric polyols and caprolactam using poly acyllactam initiation which was described previously. The reactions are as follows ... 

Figure 1. Melting point (x-ray) of segmented polyesters having a 4000 Mn polyether glycol soft segment and a polyethylene tere-phthalate hard segment (5)...

---