Polyester is an polymer materials that can be both thermoplastic and thermosetting. It depends on the processes that are applied to polyesters. In here, we explain the thermosetting polyesters and its appcations and properties. Also you can find informations about unsaturated polyesters.
As we stated in thermoplastic polyester content, polyesters contains ester linkages which gives the property that polyesters can be both thermosetting and thermoplastic. The starting polymer of thermosetting polyesters reaction of acis or anhydrids with glycol. The most known chemical reaction like that occurs between maleic anhydride(C4H2O3) and ethylene glycol(C2H6O2). With this chemical reaction, unsaturated polyester is produced. This unsaturate polyester is mixed with a monomer that starts the cross-linking process in polyester. But a phenomenon called pre-mature cross-linking in polyesters must be prevented with such an inhibitor addition.
Some applications that thermoset polyesters are used in;
Curing of thermosetting polyesters must be done in the process of molding. After the molding process, curing must be done to obtain cross-linked structure. This curing can be done with heat application or by addition of curing catalysts.
As we stated above, unsaturated polyester is produced with maleic anhydride, ethylene glycol and styrene. Styrene is used for preventing pre-mature cross-linking. Unsaturated polyester is a brittle material which has elongation according to its original shape 0%. Unsaturated polyester is produced with step polymerization process. Has tensile strength of 30 MPa and modulus of elasticity of 7000 MPa.
Properties and applications of thermosetting polyesters can be summarized like above. Do not forget to leave your comments and questions about thermosetting polyesters below. Your precious feedbacks are very important for us.