PBS and PBSA were irradiated with gamma up to a 400 kGy dose. Gel content appeared at approximately 100 kGy dose with a higher gel content for PBSA. Charlesby-Pinner analysis indicated that chains scission predominated over crosslinking. Dispersity was increased by branching, that increased molecular weight until gelation, and by chain scission that decreased molecular weight. Careful Read more about Effect of gamma irradiation on the physical properties of poly(butylene succinate) (PBS) and poly(butylene succinate-co-adipate) (PBSA)[…]

Effect of electron beam (EB) irradiation is analyzed in low and high density polyethylenes (LDPE and HDPE, respectively) at different doses. Parameters as important as degree of crystallinity, melting or crystallization temperatures are dependent on the initial PE molecular architecture, which also controls the gel content developed by action of EB irradiation and the EB Read more about Crosslinked networks in electron beam irradiated polyethylenes evaluated by proton low-field NMR spectroscopy[…]

Copoly(o-hydroxyamide)s (HPA) and copoly(o-hydroxyamide-amide)s (PAA) have been synthesized to be used as continuous phases in mixed matrix membranes (MMMs). These polymeric matrices were blended with different loads (15 and 30 wt.%) of a relatively highly microporous porous polymer network (PPN). SEM images of the manufactured MMMs exhibited good compatibility between the two phases for all Read more about Thermally Rearranged Mixed Matrix Membranes from Copoly(o-hydroxyamide)s and Copoly(o-hydroxyamide-amide)s with a Porous Polymer Network as a Filler — A Comparison of Their Gas Separation Performances[…]

There is a growing interest in multifunctional composites and in the identification of novel applications for recycled materials. In this work, the design and fabrication of multiple particle-loaded polymer composites, including micronized rubber from end-of-life tires, is studied. The integration of these composites as part of ultrasonic transducers can further expand the functionality of the Read more about Micronized Recycle Rubber Particles Modified Multifunctional Polymer Composites: Application to Ultrasonic Materials Engineering[…]

Biochar aging may affect the interactions of biochar with water and thus its performance as soil amendment; yet the specific mechanisms underlying these effects are poorly understood. By means of FTIR, N2 adsorption, Hg intrusion porosimetry, thermogravimetric analysis, 13C solid state nuclear magnetic resonance (NMR) and 1H NMR relaxometry, we investigated changes in the chemistry and structure of biochar as Read more about Response of water-biochar interactions to physical and biochemical aging[…]

In this work, using supramolecular polyurethanes theories, two polycaprolactone-based polyurethanes with 2-ureido-4-[1H]-pyrimidinone (UPy) motifs capable of forming quadruple hydrogen bonds were synthetized and characterized, focusing our attention on their capability to show thermally activated shape-memory response. In particular, 1H NMR analyses confirmed the chemical structure of the supramolecular polyurethanes, while DSC showed their totally amorphous morphology. Read more about Supramolecular Polycaprolactone-Based Polyurethanes with Thermally Activated Shape-Memory Behavior[…]

Many efforts are being made to find innovative ways of recycling rubber from end-of-life tires (ELTs), also called ground tire Rubber (GTR). Recycling through devulcanization allows the reintroduction of rubber back into the manufacturing industry. Such a process requires providing enough energy to break the sulfur links, while preventing damage to the polymeric chain. Microwave Read more about Dynamic Permittivity Measurement of Ground-Tire Rubber (GTR) during Microwave-Assisted Devulcanization[…]

The circular economy is a path that society, governments, and business must adopt to develop a viable and sustainable model for plastic production. Following the route guided by the United Nations and the new laws of the European Union, such as the Green Deal, it will be able to put an end to the great Read more about Chemical upcycling of poly(ethylene terephthalate) waste: Moving to a circular model[…]

ESR investigation of NR and IR rubber vulcanized with different cross-linking agents Express Polymer Letters, 2016, 10 (1), 2-14 Posadas, P.a , Malmierca, M.A.a, González-Jiménez, A.a, Ibarra, L.a, Rodríguez, A.a, Valentin, J.L.a, Nagaoka, T.b, Yajima, H.b, Toki, S.c, Che, J.d, Rong, L.d, Hsiao, B.S.d a Instituto de Ciencia y Tecnología de Polímeros (CSIC), C/ Juan Read more about ESR investigation of NR and IR rubber vulcanized with different cross-linking agents[…]

Effect of dose and temperature on the physical properties of an aliphatic thermoplastic polyurethane irradiated with an electron beam (2015) Radiation Physics and Chemistry, 112, pp. 61-70. Adem, E.a , Angulo-Cervera, E.a , González-Jiménez, A.b , Valentín, J.L.b , Marcos-Fernández, A.b a Instituto de Física, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad UniversitariaMéxico, D.F., Mexico b Instituto de Ciencia y Read more about Effect of dose and temperature on the physical properties[…]

I. Mora-Barrantes, J.L. Valentín, A. Rodríguez, I. Quijada-Garrido, R. París “Poly(styrene)/silica hybrid nanoparticles prepared via ATRP as high-quality fillers in elastomeric composites” Journal of Material Chemistry, 22, 1403-1410, 2012 I. Mora-Barrantes, M.A. Malmierca, J.L. Valentín, A. Rodríguez, L. Ibarra “Effect of covalent cross-links on the network structure of thermo-reversible ionic elastomers” Soft Matter, 8, 5201-5213, Read more about 2012 Artículos Científicos | Scientific articles[…]