Preparation of Cyclohexene-Sulfur Dioxide Copolymer

To a pressure vessel are added 200 ml (2.0 mole) of cyclohexene, 50 ml of 95% ethanol, and 0.30 ml of 2% aqueous hydrogen peroxide. Then 200 ml (4.6 mole) of liquid sulfur dioxide is added the vessel is sealed and kept at 25°-30°C for 24 hr. The container is cooled to — 20°C, vented, and opened. The polymer is a viscous mass which is then dissolved in 500 ml chloroform and precipitated by adding 3 liters diethyl ether. The filtered polymer is a solid and is obtained in 270-290 gm (91-98%) and contains 21.5% sulfur. 

To a cooled, glass-lined autoclave are charged 46.7 gm (0.83 mole) 1-butene, 88.3 gm (1.38 mole) sulfur dioxide, 1.0 gm Maprofix MM (60% solid sodium lauryl sulfate emulsifier supplied by Onyx Oil and Chemical Co.), 0.5 gm ammonium nitrate and 180 gm water. The autoclave is stirred at 100°F for 4 to 6 hr. After a short induction period the reaction proceeds with a considerable 

Run 2-Butene (mmoles) dioxide (mmoles) Other reactants Initiation Time (hr) temp (°C) Wt (gm) Conversion (%) 

Earlier references to these terpolymers (SOa/olefin/caibon monoxide) are known. For example, U.S. Patent 2,634,254 discloses the terpolymer prepared by polymerization in the presence of a free radical catalyst such as an azo compound. Also, U.S. Patent 4,251,340 discloses similar terpolymers prepared using irradiation as the initiator. These terpolymers are generally high melting (m.p. about 280°C) and show good structural durability for high temperature applications. 

The Drent catalyst [18d] can also be used to prepare alternating terpolymers of sulfur dioxide/ethylene/propylene that have melting points above 300 C. NMR ( C) has been run to confirm the structure, 

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