1432 FRANK H. DICKEY, FREDERICK F. RUST AND WILLIAM M. VAUGHAN Vol. 71 mers were made with 0.7% sulfur. The mercaptan-modified polymers were prepared in the same way, substituting 0.30-1.070 of dodecyl mercaptan for the sulfur. Likewise, for the unmodified polymer no change in the system was made except omission of the modifier. Samples of the latex were removed, treated with 2.5% of tetraethyl thiuram disulfide in emulsion or with ...