The effects of curing conditions on physical properties of syndiotactic 1, 2-polybutadiene (1, 2-PB) vulcanized with sulfur chloride (S₂Cl₂) were studied in the range of 1 to 10wt% in S₂Cl₂ concentration in solvents such as n-hexane, cyclohexane, benzene, carbon tetrachloride, liquid paraffin, etc., and in the range of 0.2 to 1.0mm in thickness of its 1, 2-PB samples. Tensile properties of the vulcanizates obtained by immersing of 1, 2-PB in S₂Cl₂ solution (sheet curing method) were found to depend largely on the heterogeneity of the distribution of crosslinks in the sample. The best physical properties of the vulcanizates were obtained by curing under conditions such as 5wt% of S₂Cl₂ in n-hexane solution, 0.4mm in the sample thickness. Excellently homogeneous distribution of combined sulfur in the vulcanizates and good physical properties were obtained by pre-immerseing and swelling the sample sheets in pure solvent, followed by curing with S₂Cl₂ solution (swollen sheet-curing method).

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