Sulfur vulcanization sulfur is not miscible in the polymer prior to vulcanization and attention is paid to prevent sulfur bloom, where it migrates to the surface of the article. Accelerators act much like catalysts allowing vulcanisation to be performed cooler yet faster and with a more efficient use of sulfur. They achieve this by reacting with and breaking the sulfur ring to form a reactive intermediate, referred to as a sulfurating agent. This in turn reacts with cure sites in the rubber to bring about vulcanization. There are two major classes of vulcanization accelerators: primary accelerators and secondary accelerators (also known as
Polymer architecture crosslinked to allow flaking of the rubber and prevent damage to the paper. Polymerization of pure sulfur at higher temperatures also explains why sulfur becomes more viscous with elevated temperatures in its molten state. A polymer molecule with a high degree of crosslinking is referred to as a polymer network. A sufficiently high crosslink to chain ratio may lead to the formation of a so-called infinite network or gel, in which each chain is connected to at least one other. With the continual development of Living polymerization, the synthesis of polymers with specific architectures becomes more and more facile. Architectures