2- Vinyl-1,4-butanediols

Because of its relatively high, price, there have been continuing efforts to replace acetylene in its major appHcations with cheaper raw materials. Such efforts have been successful, particularly in the United States, where ethylene has displaced acetylene as raw material for acetaldehyde, acetic acid, vinyl acetate, and chlorinated solvents. Only a few percent of U.S. vinyl chloride production is still based on acetylene. Propjiene has replaced acetylene as feed for acrylates and acrylonitrile. Even some recent production of traditional Reppe acetylene chemicals, such as butanediol and butyrolactone, is based on new raw materials. 

Vinyl Ethers. The principal commercial vinyl ethers are methyl vinyl ether (methoxyethene, C H O) [107-25-5], ethyl vinyl ether (ethoxyethene, C HgO) [104-92-2], and butyl vinyl ether (1-ethenyloxybutane, C H 20) [111-34-2]. (See Table 8 for physical properties.) Others such as the isopropyl, isobutyl, hydroxybutyl, decyl, hexadecyl, and octadecyl ethers, as well as the divinyl ethers of butanediol and of triethylene glycol, have been offered as development chemicals (see Ethers). 

The principal chemical markets for acetylene at present are its uses in the preparation of vinyl chloride, vinyl acetate, and 1,4-butanediol. Polymers from these monomers reach the consumer in the form of surface coatings (paints, films, sheets, or textiles), containers, pipe, electrical wire insulation, adhesives, and many other products which total biUions of kg. The acetylene routes to these monomers were once dominant but have been largely displaced by newer processes based on olefinic starting materials. 

As Figure 14 also shows, the only acetylene derivatives to sustain growth during this period were the so-called acetylenic chemicals. These include 1,4-butanediol, vinyl ethers, A/-vinyl-2-pyrroHdinone, and butanediol. Of these, 1,4-butanediol, a principal feed for tetrahydrofuran, accounts for over 90% of the acetylenic chemicals demand (38). 

The U.S. Department of Commerce estimates total production of about 163,000 t in 1990. Other estimates based on demand data indicate that it was as high as 175,000 t. With demand and supply in balance, it is estimated that in 1997 the demand will be 185,000 t. The distribution in product demand is projected to be the following 1,4-butanediol and other acetylenic chemicals (45%), vinyl chloride monomer (45%), acetylene black (5%), and industrial use (5%). 

Of the estimated 710,000 t consumed in 1990, 25% was used to produce vinyl chloride [75-01-4] monomer (VCM), 14% for vinyl acetate [108-05-4] monomer (VAM), 23% for butanediol, 14% for industrial use, and the balance to produce other products such as acryUc acid, synthetic mbber, chlorinated solvents, and acetylene black. The demand for PVC is expected to decrease as legislation limiting its use in packaging is pending. Consequentiy, VCM consumption will also suffer. 

Detailed studies on the lipase-catalyzed polymerization of divinyl adipate and 1,4-butanediol were performed [41-44]. Bulk polymerization increased the reaction rate and molecular weight of the polymer however, the hydrolysis of the terminal vinyl ester significantly limited the formation of the polyester with high molecular weight. A mathematical model describing the kinetics of this polymerization was proposed, which effectively predicts the composition (terminal structure) of the polyester. 

Tang B, Liaoa X et al (2010) Enhanced production of poly(vinyl alcohol)-degrading enzymes by mixed microbial culture using 1,4-butanediol and designed fermentation strategies. Polym Degrad Stab 95 557-563... 

Acetylene and formaldehyde are reacted in the presence of a highly active catalyst to form butynediol, which is hydrogenated to butanediol and then cyclodehydrogenated to form butyrolactone. Pyrrolidone is produced by reacting butyrolac-tone with ammonia. This is followed by a vinylation reaction in which pyrrolidone and acetylene are reacted under pressure. The monomer vinylpyrrolidone is then polymerized in solution, using a catalyst. Crospovidone is prepared by a popcorn polymerization process. 

CO. CO , butadiene, tetrahydrofuran. toluene, benzene. 1.5-hexadiene. dihydrofuran. 4-vinyl cyclohexene. 1,4-butanediol. benzaldehyde. benzoic aad. terephihaldehydic acid, terephlhahc acid, mono-3-butenyl terephthaiate, cyclic dimer, short chain fragments... 

Use Manufacture of vinyl chloride vinylidene chloride vinyl acetate acrylates acrylonitrile acetaldehyde per- and trichloroethylene cyclooctatetraene 1,4-butanediol carbon black and welding and cutting metals. 

Acetylen Acetylene EINECS 200-816-9 Ethine Ethyne HSDB 166 Narcylen UN1001, An asphyxiant gas intermediate for manufacture of vinyl chloride, vinylidene chloride, vinyl acetate, acrylates, acrylonitrile, acetaldehyde, perchloroethylene trichloroethylene, 1,4-butanediol, carbon black, welding and cutting metals. Colorless gas mp = -81° d = 1,166 g/l (0°, 760 mm), d of gas = 0.90 (air = 1) soluble in H2O (1 1 v/v), soluble in AcOH, EtOH, Et20, CeHe, MezCO LC (rat inh) = 9000 ppm. Air Products Chemicals Inc. BASF Corp. BOC Gases Union Carbide Corp. 

PVC with poly(butanediol-terephthalate-adipate) and 30 wt% GF Vinylchloride polymerized in the presence of PI, blended with PVC and MBA PVC with poly(methylmethacrylate-co-maleimide-co-vinyl cyanide) and styrene-cyclohexyl-maleimide-grafted butadiene PVC with imidated poly methacrylate (polyglutarimide, PGI)... 

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