Novel Polyfunctional Isocyanates for the Synthesis of Model Networks

Abstract

Polymer networks are of great importance for technical applications as well as in the scientific field. Thermoset polymers like epoxy resins, macroporous polymeric gels as used for polymeric reagents or catalysts, vulcanized rubber, and thermoplastic elastomers are examples for the wide spread use of crosslinked polymeric structures. Theories have been derived to predict gelation behavior, the built up of molecular weight, and mechanical properties as a function of the extent of reaction (1–3). Structure-property-relationships, a deeper understanding of elasticity, of the process of network formation, and of network theories, however, can be derived only from networks with well defined structure. The manufacture of such well defined or model networks, on the other hand, depends on the availability of suitable monomeric or oligomeric precursors and a clean, complete reaction by which chain extension and crosslinking is achieved. This will allow to control network parameters like crosslink density or the molecular weight between crosslinks.