Polytetramethylene ether

Uses. Furfural is primarily a chemical feedstock for a number of monomeric compounds and resins. One route produces furan by decarbonylation. Tetrahydrofuran is derived from furan by hydrogenation. Polytetramethylene ether glycol [25190-06-1] is manufactured from tetrahydrofuran by a ring opening polymeri2ation reaction. Another route (hydrogenation) produces furfuryl alcohol, tetrahydrofurfuryl alcohol, 2-methylfuran, and 2-methyltetrahydrofuran. A variety of proprietary synthetic resins are manufactured from furfural and/or furfuryl alcohol. Other... 

As can be seen, most of the furfural produced in this country is consumed as an intermediate for other chemicals. Hydrogenation to furfuryl alcohol is the largest use. Some of the furfuryl alcohol is further hydrogenated to produce tetrahydrofurfuryl alcohol. The next major product is furan, produced by decarbonylation. Furan is a chemical intermediate, most of it is hydrogenated to tetrahydrofuran, which in turn is polymerized to produce polytetramethylene ether glycol (PTMEG). 

Butanediol [110-63-4] (BDO) goes primarily into tetrahydrofuran [109-99-9] (THE) for production of polytetramethylene ether glycol (PTMEG), used ia the manufacture of polyurethane fibers, eg, Du Font s Spandex. THE is also used as a solvent for PVC and ia the production of pharmaceuticals (qv). Lesser amounts of BDO are employed ia the production of polybutylene terephthalate resias and y-butyrolactone. 

Thermoplastic copolyester elastomers are generally block copolymers produced from short-chain aUphatic diols, aromatic diacids, and polyalkjlene ether-diols. They are often called polyesterether or polyester elastomers. The most significant commercial product is the copolymer from butane-l,4-diol, dimethyl terephthalate, and polytetramethylene ether glycol [25190-06-1J, which produces a segmented block copolyesterether with the following stmcture. 

Polybutester (10) is a polyether—ester produced by the condensation polymerization of dimethyl terephthalate, polytetramethylene ether glycol [25190-06-17, and 1,4-butanediol [110-63-4]. Polybutester sutures are available in clear, ie, undyed, or blue, ie, melt-pigmented with (phthalocyaninato(2-)) copper. Monofilament polybutester is sold under the trade name Novafil. 

Most of the commercial polymers consist of polyether blocks separated by polyamide blocks. The polyether blocks may be based on polyethylene glycol, polypropylene glycol or, more commonly, polytetramethylene ether glycol. The polyamides are usually based on nylon 11 but may be based on nylons 6 or 66 even a copolymer, e.g. 6/11. 

In 1978 Hiils (Mumcu et al ) described the properties of a block copolymer prepared by condensation of polytetramethylene ether glycol with laurin lactam and decane-1,10-dicarboxylic acid. The materials were introduced as XR3808 and X4006. The polyamide XR3808 is reported to have a specific gravity of 1.02, a yield stress of 24 MPa, a modulus of elasticity of 300 MPa and an elongation of break of 360%. The Swiss company Emser Werke also introduced similar... 

A calibration curve was obtained from C-NMR spectra of a series of polytetramethylene ether (PTME)-THF/CH3N02 solutions at... 

Figure 1 shows the proton noise-decoupled C-NMR spectrum of a polytetrahydrofurein (polytetramethylene ether glycol, PTMEG) dissolved in THF. In this spectrum the carbons numbered 1, 2 and 3 which cure a to the oxygen appear at lower field them the 6-carbons labeled as 4, 5 and 6. The carbon atoms in the polymer are clearly resolved from the corresponding carbons of the THF monomer. The fact that carbons 3 and 4 near the hydroxyl end-groups can be easily identified shows the excellent resolution of this technique. 

Butanediol (BDO) goes primarily into tetrahydrofuran (THF) for production of polytetramethylene ether glycol (PTMEG), used in the manufacture of polyurethane fibers. 

Pellethane 2103-80A (Upjohn) poly(co-polytetramethylene ether glycol-diphenylmethane diisocyanate). Polyurethane 2000E poly(co-propyleneglycol-4,4 -diphenylmethanediisocyanate-ethylenediamine). 

Polyether polyols are usually produced by the polymerisation of ethylene or propylene oxide in the presence of a polyfunctional alcohol or amine as an initiator. Copolymers are also produced from mixtures of ethylene oxide and propylene oxide with di and tri -OH functionality. Polytetramethylene ether glycols (PTMEG) from tetrahydrofurans are also found. 

In general, the PTHF is needed in the diol form (with OH end groups). This form is called PTMEG which stands for polytetramethylene ether glycol. It is also known as POLYMEG (a trade name of QUAKER OATS). Conversion of the diacetate form to the diol form can be carried out as follows ... 

Another method of producing polyether polyols is the ring-opening polymerization of cyclic ethers, such as tetrahydrofuran, to produce polytetramethylene ether glycols or poly(oxytetramethylene) glycols, (PTMEG), as shown below. 

AR = the aromatic moiety of the dicarboxylate D = the alkylene portion of a short-chain diol x = the number of tetramethylene ether units in the polytetramethylene ether glycol... 

Although this paper is concerned primarily with polytetramethylene ether glycol as the polymeric component of the copolyester elastomer, other polyglycols can be used for example, polyethylene ether glycol and poly-1,2-propylene ether glycol. Various combinations of short-chain diols and dicarboxylates may be used also, as mentioned (4). 

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