High pressure polymerisation of unsatd. cpds. - using initiator cpds. of different activity in piston compressor cylinder to save energy

摘要

In the polymerisation of unsatd. cpds. under high pressure and elevated temp., one or more initiators of different activity are used in the polymerisation reaction taking place in the cylinder of a piston compressor. It is pref. to add inhibitor of the decompsn. reaction to the reaction mixt. All or much of the energy used for recompressing the unchanged charge when compression, polymerisation and expansion are carried out in separate pieces of appts. is saved by using a single piece of appts., which resembles a 2-stroke diesel engine. Processes of this type are useful in the gas phase polymerisation of ethylene, propylene, vinyl chloride etc., using O2, peroxide, azo cpds. etc. as initiators.