Abstract: Processes of synthesizing long-chain branched polymers. The processes include contacting together one or more C2-C14 alkene monomers, at least one diene, optionally a solvent, and a multi-chain catalyst optionally in the presence of hydrogen, wherein the multi-chain catalyst comprises a plurality of polymerization sites; producing at least two polymer chains of the C2-C14 alkene monomers, each polymer chain polymerizing at one of the polymerization sites; synthesizing the long-chain branched polymers by connecting the two polymer chains with the diene, the joining of the two polymer chains being performed in a concerted manner during the polymerization; and producing tri-functional long chain branches from the diene, wherein the tri-functional long chain branches occur at a frequency of at least 0.03 per 1000 carbon atoms.