Liquid polysulfide oligomers have been prepared in bulk as well as under the conditions of known methods. Styrene, methacrylic acid and sulfur were used as starting materials. The composition of the oligomer products was determined by using IR spectroscopy as the principal method. The absorption bands at 1600 and 700 cm−1for styrene and 1697 cm−1for methacrylic acid were employed as an analytical tool. Both the kind of chemical bonds between the monomer fragments and length of polysulfide bonds were studied by the combined application of IR and1H NMR spectroscopy. Methacrylic acid was found to be bound chemically to the sulfur atomsviaits vinylidene group and the class of polysulfidity decreased from 2.8 to 2.5.