STUDY OF CYANO-DERIVATIVES OF PROPENE AS TRANSFER AGENTS IN RADICAL POLYMERIZATIONS

A new procedure for determining transfer constants, depending on knowl edge of the numbers of initiator fragments in the average molecules of appropriate polymers, has been applied to crotono-nitrile (1-cyano-1- propene) and allyl cyanide (3-cyano-1-propene) with methyl methacrylat e and styrene at 60 degrees C. Allyl cyanide is the more reactive of t he two additives, but is less effective than allylbenzene (3-phenyl-1- propene); neither of the cyano-derivatives causes appreciable retardat ion.