Allyl peroxide chain transfer agents

Peroxides useful as chain transfer agents in radical (co)polymerization of monomers wherein said organic peroxides are represented by the following formula:

• ##STR18## wherein n is an integer from 2-4,
• R.sub.1 and R.sub.2 may be the same or different and are selected from the group consisting of hydrogen and lower alkyl or R.sub.1 and R.sub.2 may combine to form a C.sub.5 -C.sub.7 aliphatic ring, R.sub.3 has a valency of n and
• when n=2, R.sub.3 is an alkylene group having 8-12 carbon atoms, an alkynylene group having 8-12 carbon atoms or a group of the general formula:
• ##STR19## wherein q=0 or 1, and
• R.sub.7 is an isopropenyl group, a 2-hydroxyisopropyl group, and an isopropyl group:
• ##STR20## wherein R.sub.8, R.sub.9 and R.sub.10 are independently selected from the group consisting of alkyl, alkenyl and aryl groups all of which may be optionally substituted with one or more of hydroxyl, amino, epoxy and carboxy groups, hydrogen, or two of R.sub.8, R.sub.9 and R.sub.10 may combine to form a ring;
• or the group --COOR.sup.6 where R.sup.6 is hydrogen or an optionally substituted alkyl, alkenyl or aryl group;
• and
• when n=3, R.sub.3 =1,2,4-triisopropylbenzene-.alpha.,.alpha.',.alpha.'-triyl;
• and
• for n =2-4,
• R.sub.3 can be a silicon-containing group and
• X is an electron withdrawing group and together with R.sub.1, may combine to form a C.sub.5 -C.sub.7 aliphatic ring,
• m is 0 or 1 and
• Z is selected from the group consisting of ##STR21##