PVC, K = 70,67, and 61, was polymerized in a 10-L autoclave at 53, 57, and 62degreesC, resp., with aqueous 40% 1,1,3,3-tetramethylbutyl peroxy-neodecanoate (I), 50% tert-butyl peroxy-neodecanoate (II), 40% tert-butyl peroxy-neoheptanoate (III), 40% diethylhexyl peroxydicarbonate (IV), or 40% III + 40% IV emulsion. Then PVC K = 70 was polymerized in a 135-m(3) autoclave at 53degreesC with aq. 50% II, or I + IV or I + II, or IV emulsions. The PVC K = 67 and K = 70 were polymerized in a 6-day industrial-plant operation with mixed initiator emulsions, I + II and I + IV. The VC conversions compared well with those achieved with conventional initiators. All the standardized properties of the resulting PVC powder met the requirements. The powder was pure and whiter and polymerization times shorter by a few percent.