Day 1 :
Applied Chemistry Research Center (CIQA), México
Time : 09:20-10:00
Saul Sanchez has his expertise in preparation and characterization of polymer nanomaterials. He is a senior researcher at Applied Chemistry Research Center (CIQA) for more than 29 years. He received his PhD in Materials Engineering from the UANL in Mexico. He has published more than 70 technical papers, 6 patents and 3 books related to polymer material science, and has supervised more than 20 MSc and PhD thesis. His research work at CIQA has been related most with: polymer processing, polymer nanocomposite materials, polymer functionalization, and characterization.
The combination of keratin fibers, obtained from feathers, with deoxyribose nucleic acid (DNA) is employed in low-density polyethylene-ethylene vinyl acetate (LDPE/EVA) blends using DNA coating with a segregated structure in order to enhance the blend flame retardant properties. The combined effect of each filler and the using of PEgMA as compatibilizer on PE/EVA flame retardant properties were analyzed. DNA by its chemical structure can be considered as an intumescent or blowing agent and when it is combined with keratin the char formation is promoted and the flame retardant properties are enhanced. Instead of melt compounding in the polymer bulk, DNA was distributed along specific layers forming a segregated network which resulted in better PE/EVA blend flame retardant properties. Limiting oxygen index (LOI), cone calorimeter determinations and flammability test (Underwriters Laboratory –UL-94) were used to evaluate the flame retardant properties. The composite morphology was determined by scanning electron microscopy (SEM). The mechanical properties were also evaluated by Dynamic-mechanical analysis (DMA). This filler combination significantly reduces the burning rate during horizontal flammability tests, increases the limit oxygen index and reduces the heat release rate during cone calorimetry tests. The flame retardant behavior was compared with a reference PE/EVA sample with 55 wt% of Magnesium Hydroxide currently used for wire coatings in the wire and cable industry. The results indicated that the combination of both types of fillers makes it possible to reduce the total Magnesium hydroxide filler content from 55 to 20% to achieve good flame retardant properties.
University of Concepcion, Chile
Time : 10:00-10:40
Bernabé L Rivas has completed his PhD at the University of Concepcion (1980) and postdoctoral studies from Tuebingen University, Germany with Humboldt Foundation Fellows (1989-1991). He is the Vice Rector of the University of Concepción. The leader of the research group about Synthesis and Applications of -Functional Polymers, Polyelectrolytes, Resins with Retention Properties for Pollutants Ions.–Polychelatogens in combination with ultrafiltration membranes. Polymer-metal complexes as biocides. Nanocomposites from polypropylene and biopolymers. He has published more than 400 papers in reputed journals, 29 chapter of books, h factor 34, and has been serving as an editorial board member of journals.
Membrane filtration easily allows this separation by means of the method known as the liquid-phase polymer-based retention (LPR) technique. Applications of water-soluble polymers to the homogeneous enrichment or selective separation of various metal ions from dilute solutions have been reported. Through to washing or enrichment methods, Cr(VI), V(V), Mo(VI), B(V), and As(V) removal experiments were carried out at different pH using water-soluble cationic polymers (WSCPs) containing quaternary ammonium salts. The results showed the highest retention capacity of oxyanions depending on the pH. Polymer-clay nanocomposites researchers have presented a great attention from the scientific community because nanocomposites materials present enhanced properties (mechanical, thermal, and barrier properties) compared with starting material (unloaded polymers). The use of polymer matrix with organic functional with the capability to retain ion and filler such as clays lead to nanocomposite ion exchange resins. We have studied polymer nanocomposite loaded with layered double hydroxide (LDH) as sorbents for oxyanions such as arsenate, chromate, and vanadate. Under different experimental conditions, the composite exhibited a high sorption reaching almost a 100% of removal. Also, the sorption of oxyanions presented a fast kinetics. Selectivity experiments showed that there is not a significant decrease in sorption capacity.
ECHO Exhibitor Session by Tine Zlebnik 11:00-11:40 Panel Discussion 11:40-11:50