Controlled-Release Pesticides : 3. Herbicidal Synthetic Polymer

Copoly(S-vinylisothiourea-vinylene-vinyl thiocyanate) was prepared from poly(viny1 chloride) with thiourea as an attempt to develop controlled-release herbicides. The copolymer was decomposed in an aqueous alkaline solution to give thiocyanate and other compounds. The copolymer was also decomposed by acid releasing low molecular compounds. The copolymer was not effective for germination but inhibited the growth of seedlings of barnyard grass on the treated soil for 28 days. The copolymer treated with acid or base was more effective on the germination and the growth of the plant