EFFECT OF ZNO NANOPARTICLES ON PROPERTIES OF NANOCOMPOSITE COATING BASED ON ACRYLIC POLYMER EMULSION AND GRAPHENE OXIDE

Effect of ZnO nanoparticles on nanocomposite coatings based on R4152 and graphene oxide (GO) was studied.In presence of 2%wt. ZnO nanoparticle, abrasion resistance of coating increased by nearly 25% (from 75 to 92.9 L/mil) and temperature decomposition raised by 18oC. SEM images showed that nano ZnO can disperse homogenously in polymer matrix in presence of GO. Hence, photocatalytic activity of R4152/GO/ZnO nanocomposite coating was higher than that of R4152/ZnO nanocomposite coating. After 14 hours UV exposure, R4152/GO/ZnO nanocomposite coating can degrade over 80% methylene blue coated on its surface while 60% methylene blue was degraded by R4152/ZnO coatings.

EFFECT OF THE HEAT TREATMENT OF Hovenia dulcis Thunb. WOOD ON THE PRODUCTION OF EGP PANELS WITH DIFFERENT ADHESIVES

The objective of this work was to analyze the shear strength of edge-glued panels (EGP) made from the H. dulcis Thunb. wood thermally modified by the VAP HolzSysteme® process. Initially, the Hovenia dulcis samples were heat-annealed by the VAP HolzSysteme® process, and then bonded with Resorcinol-formaldehyde (RF), Melamine-urea-formaldehyde (MUF), Isocyanate Polymer Emulsion (EPI) and Polyvinylacetate (PVAc) and submited to pre-treatments for dry, humid and external environment and without pre-treatment to evaluate the shear strength, 5th percentile and failure in the wood. It was observed a decrease in the shear strength of the thermorrectified H. dulcis wood for all adhesives. All adhesives obtained results superior to the minimum required by the standard EN13354 (2009) for the wood without pre-treatment as for the wood without thermoregulation as well as for the heat treated wood, and may be used for non-structural purposes. However, for the external environment (three cycles) only the MUF adhesive obtained value that meets the minimum standards of the standard, in this way, it is suggested to glue the EGP of H. dulcis without thermortification and with thermorrectification using the MUF adhesive, which has achieved better performance offering greater resistance in dry, wet and external environments.

Effect of Alkali Hydroxide on the Properties of PTFE Graphite Bonded Aluminium Titanium Composite Sheet

This study focused on the effect of some alkali hydroxide on the properties of a composite sheet prepared by power spray coating of clean aluminium-titanium sheets with PTFE/graphite emulsion. The blank sheets were washed with hot water and dried at 80 °C for 5-6 minutes before power spraying of colorless polytetrafluoroethylene PTFE/graphite emulsion in perfluoro kerosene followed by hot-rolling under a pressure of 150-200 KPa at the temperature 50 °C higher than the melting temperature of the PTFE polymer (Du Pont). The obtained sandwich was sintered at 550 °C for a few minutes. Alkali hydroxide was added to the polymer emulsion before spraying. Results showed that temperature and time enhanced the extent of adhesion of the two metals to form a homogeneous composite metal sheet. Alkali hydroxide inclusion deteriorates the stability of the prepared sheet. The alkali effect was because PTFE is inactive material, Incompatible with molten alkali metals and alkali hydroxide. The disability of the alkali hydroxide to be incompatible with the polymer material experienced changes in its intrinsic properties. Alkali halides have insignificant effect. Alkali halides just displayed a filling in material.