OLIGOMERS [uh-lig-uh-mer]
What it is: Part of the acrylic family, an oligomer sits between a liquid and a solid (a semi-solid), sometimes referred to as a pre-polymer. Oligomers are short chains of acrylate monomers that are partially polymerized and usually very thick and stringy, often having a gel-like or resin appearance.
How it is used: UV/LED hard gels are oligomers that require curing under a lamp.