Poly(-caprolactone) diols (HOPCLOH) and their poly(ester-urethane)s (PEUs): The effect of linear aliphatic diols [HO-(CH2)m-OH] as initiators

α,ω-Hydroxy telechelic poly(ε-caprolactones) were prepared by ring-opening polymerization of the ε-caprolactone catalyzed by ammonium decamolybdate in the presence of different aliphatic diols [HO–(CH2)m–OH, where m ¼ 2, 4, 6, 8, 10, 12, 14, and 16] as initiators to obtain a family of α,ω- hydroxy telechelic poly(ε-caprolactone) [HO–PCL–O–(CH2)m–O–PCL–OH, m ¼ 2, 4, 6, 8, 10, 12, 14, and 16]. The content of the alkyl group (AG) (–(CH2)m–) had an important effect on the crystallinity (xi) of α,ω-hydroxy telechelic poly(ε-caprolactone), showing a proportional relationship. In poly (ester-urethanes) derived from α,ω-hydroxy telechelic poly(ε-caprolactones) and 1,6- hexamethylene diisocyanate, the AG also showed a similar effect on the xi and eventually on the mechanical properties, increasing the values of the modulus. Therefore, AG content was a factor to induce a plastic behavior in poly(ester-urethanes). The effect of AG on the water uptake of poly(ester-urethanes) after 1 week was negligible.José E. Báez thanks the “Programa para el Desarrollo Profesional Docente (PRODEP, Protocolo 166155)”, Dirección de Apoyo a la Investigación y al Posgrado (DAIP) at University of Guanajuato (UG), Consejo Nacional de Ciencia y Tecnología (CONACYT) and “Sistema Nacional de Investigadores (SNI)” in Mexico for financial support of the work. José E. Báez also thanks Ángel Marcos-Fernández for believing in these ideas and providing financial support for the reagents. José E. Báez also thanks the UG for the recent opportunity to work as an Assistant Professor. Marvin was used for drawing, displaying, and characterizing chemical structures, substructures, and reactions (Marvin Sketch 6.1.3, 2013, ChemAxon; http://www.chemaxon.com); a free software program with an academic license was provided by ChemAxon. Finally, José E. Báez thanks to MSc Paulina Lozano and Dr. Ricardo Navarro Mendoza for the acquisition of SEM micrographs in the “National Laboratory for the Characterization of Physicochemical Properties and Molecular Structure” at the University of Guanajuato. Ángel Marcos-Fernández would like to thank the Ministry of Economy and Competitiveness (MINECO) for the financial support of this work within the framework of the Plan Nacional de IþDþI through the research project MAT2014-52644-R.Peer Reviewe