In one embodiment, this invention relates to a solventless liquid isoprene compound. The compound includes a liquid isoprene rubber. The compound also includes a curing agent selected from sulfur and/or sulfur donors. The curing agent is present in an amount of at least about 3% by weight of the compound. The compound contains substantially no solvent. In another embodiment, this invention relates to a solventless liquid isoprene compound. The compound includes a liquid isoprene rubber. The compound also includes a nonsulfur curing agent. The curing agent is present in an amount of at least about 5% by weight of the compound. The compound contains substantially no solvent.