Time filter

Source Type

Bandeira L.C.,University of Franca | de Campos B.M.,University of Franca | Calefi P.S.,University of Franca | Ciuffi K.J.,University of Franca | And 4 more authors.
Journal of Nanostructured Polymers and Nanocomposites | Year: 2011

This work investigates changes in the properties of macroporous (pore size = 500μm) samples of the polymers polyamide 12 (nylon) and acrylonitrile-butadiene-styrene (ABS), obtained by rapid prototyping (RP). The sols containing silicon and calcium alkoxide, with or without phosphate anions, were deposited onto the polymers by the dip-coating technique. Thermal analysis revealed an increase in the decomposition temperature of the materials prepared by RP, attributed to the coating. SEM demonstrated good adherence, dense and thick coatings, coverage of the micropores, and approximately 30% decrease in the number of macropores. Samples containing phosphate were better coated compared with samples without phosphate in relation to adhesion and homogeneity. In conclusion, RP and the sol-gel route are efficient for polymer coating and could be used in a variety of applications as aircrafts, automobiles, telecommunications, and biomodels.

De Souza E.A.,University of Franca | Azevedo C.B.,University of Franca | Rocha L.A.,University of Franca | De Faria E.H.,University of Franca | And 6 more authors.
Journal of Materials Research | Year: 2012

In this article, the sol-gel methodology was used for coating an acrylonitrile butadiene styrene (ABS) polymer prepared by the rapid prototyping technology with a colloid containing the europium III dipicolinic complex, which presents high emission when excited in the ultraviolet region. Either acid or base was used for treatment of the ABS polymer, with a view to activating its surface. The thermal analysis evidenced a residual mass after 600 °C, which indicated that the coating adhered to the substrate. X-ray diffraction analysis showed that the structure of the ABS polymer was not affected by the sol-gel treatment. The large band centered at 287 nm, ascribed to ligand-metal charge transfer, can be used to excite the europium III dipicolinic complex in the ultraviolet C and ultraviolet B regions. The emission appears in the characteristic red region of the electromagnetic spectrum. These results indicate that the obtained material is a candidate for use as ultraviolet sensor. © Materials Research Society 2012.

Discover hidden collaborations