What is the difference between urethane, rubber and plastic?
Differences between polyurethane, rubber and plastic are in the manufacturing methods, properties and resulting applications. Synthetic rubbers and plastics are generally manufactured by a polymerization process, either addition polymerization or condensation polymerization. In addition polymerization an unsaturated monomer polymerises by a chain reaction via a free radical or ionic mechanism and the reaction can be controlled only within certain limits. Condensation polymerization or step polymerization involves the reaction by the use of heat and/or catalysts between small to medium sized poly – functional molecules and the formation of water, sodium chloride or similar low weight compounds. Polyurethane elastomers do not easily fit into either of these. Low to medium molecular weight polyfunctional compounds, one of which is a diisocyanate , are joined together by an addition type process but by an intermolecular hydrogen transfer and not by free radical or ionic mechanism. Cross li
