This volume contains papers presented at Symposium 5C, 'New Trends in Polymer Chemistry and Characterization' of the XXIII International Materials Research Congress organized by the Sociedad Mexicana de Materiales A. C. in collaboration with the Materials Research Society (MRS), USA, which was held from 17–21 August 2014 in Cancún, Mexico. The symposium was devoted to fundamental and technological applications of polymeric materials, and continued the tradition of providing a forum for scientists from various backgrounds with a common interest in the development and use of polymeric materials to come together and share their findings and expertise. The topics included step-growth and chain-growth polymerizations, macromolecular architecture and topology, well-defined and uniform polymers, polymer engineering and processing, polymer characterization by new and combined techniques, polymer morphology, dendrimers and hyperbranched polymers, smart and functional polymers, composite materials and coatings, polymer-forming reactions, modeling and simulation methods in polymer chemistry and physics, environment-friendly polymers and biopolymers.