The authors would like to thank the vice-rectorate for research of the Pontificia Universidad Católica del Perú and the Peruvian Council of Science and Technology (Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica–Fondo Nacional de Desarrollo Científico y Tecnológico) for financial support. Dr Vicente Lorenzo from the Polytechnical University of Madrid is acknowledged for providing technical support during the microhardness tests.

The Vice-Rectorate for Research (VRI-PUCP) of the Pontificia Universidad Catolica del Peru and the National Council of Science, Technology and Technological Innovation (CONCYTEC-FONDECYT) are greatly acknowledged for financial support. The Institute of Polymer Science and Technology of the Spanish Council for Scientific Research (ICTP-CSIC, Madrid, Spain) is acknowledged for experimental assistance.