José António da Purificação Martins

José António Martins teaches Polymer Science at the Department of Polymer Engineering of the University of Minho and is a member of CICECO since July 2005. He was graduated in Physics by the University of Lisbon, had a Master degree in Materials Science by the Technical University of Lisbon and University of Minho, and he got a PhD in 1996 by the University of Minho in Polymer Science.

General: Polymer Physics Specific: The current research is focused on two areas. The first one is related to shear-induced isothermal and non-isothermal crystallization kinetics, the melt morphology at the steady-state, the size of shear-induced precursors, the molecular origin of orientation in sheared melts, and the physical nature of entanglements. Work developed so far allowed to quantify the number of entanglements at the steady-state in steady-shear, to predict the size of shear-induced precursor structures in critically sheared melts, to show inconsistencies in flow theories of polymer melts based on the tube concept, and to establish a clear relationship between precursor structures and entanglements. The second area, which is not so developed as the previous one, mainly due to the lack of funding, is related to the development of coatings, based on blends of conductive polymers and nanocomposites, for absorption of microwave radiation.

Weidong Zhang (Post-Doc) Joanna Krakoviak (PhD student)

National: J. J. C. Cruz Pinto Ana Barros-Timmons Tito Trindade Abroad: Andrzej Galeski (Lodz, Poland)

Polymer Science and Polymner Physics

POCTI/CTM/46270/2002 QUANTITATIVE ANALYSIS OF SHEAR EFFECTS ON THE SOLIDIFICATION OF POLYMERS WITH A SHEAR-DSC Funding: FCT Start date: October 2004; End date: October 2007

Five publications by my order of relevance: 1. J. A. Martins, Wd. Zhang, A. M. Brito, Saturation of shear-induced isothermal crystallization of polymers at the steady-state and the entanglement-disentanglement transition, MACROMOLECULES, aceite, a ser publicada em 2006. 2. W. Zhang, J. A. Martins, Evaluation of the Effect of Melt Memory on Shear Induced Crystallization of Low Density Polyethylene, MACROMOLECULAR RAPID COMMUNICATIONS, 27, 1067 (2006). 3. J. A. Martins, J. J. C. Cruz Pinto, Evaluation of the instantaneous nucleation density in the isothermal crystallization of polymers, POLYMER 43 (14): 3999-4010 (2002). 4. J. A. Martins, J. J. C. Cruz-Pinto, The temperature calibration on cooling of differential scanning calorimeters, THERMOCHIM ACTA 332 (2): 179-188 (1999). 5. J. A. Martins, M. C. Cramez, M. J. Oliveira, R. J. Crawford, Prediction of spherulite size in rotationally molded polypropylene, J MACROMOL SCI PHYS B42 (2): 367-385 (2003). Other publications by subject: A. Crystallization under quiescent conditions. 1. Martins JA, Cruz Pinto JJC, Oliveira MJ, Polymer crystallization: isothermal and non isothermal spherulite growth-parameters from optical microscopy and differential scanning calorimetry, J THERM ANAL 40 (2): 629-636 (1993). 2. Cruz Pinto JJC, Martins JA, Oliveira MJ, The isothermal crystallization of engineering polymers – POM and PEEK, COLLOID POLYM SCI 272 (1): 1-16 (1994). 3. Martins JA, Cruz Pinto JJC, Prediction of poly(oxymethylene) crystallization behaviour from isothermal data , J THERM ANAL 40 (2): 621-628 (1993). 4. Martins JA, Nonisothermal crystallization kinetics of PP after DSC calibration on cooling., ABSTR PAP AM CHEM S 218: 168-PMSE Part 2 (1999). 5. Martins JA, Pinto JJCC, Non-isothermal crystallisation kinetics with instantaneous nucleation, POLYMER 41 (18): 6875-6884 (2000). 6. Martins JA, Pinto JJCC, The nonisothermal crystallization kinetics of polypropylene after DSC calibration on cooling, J MACROMOL SCI PHYS B39 (5-6): 711-722 (2000). 7. Esteves AC, Barros-Timmons AM, Martins JA, Zhang W¸ Cuz-Pinto JJC, Trindade T, Crystallization behaviour of new poly(tetramethyleneterephthalamide) nanocomposites containing SiO2 fillers with distinct morphologies, COMPOSITES PART B. 36: 51-59 (2005). B. Thermal Analysis 1. Martins JA, Alves NM, Mano JF, Pinto JJCC, Temperature correction of dynamic mechanical and thermomechanical analysers during heating, cooling and isothermal experiments (vol 346, pg 133, 2000), THERMOCHIM ACTA 369 (1-2): 175-178 (2001). 2. Martins JA, Malheiro MJA, Teixeira JC, Pinto JJCC, The role of the temperature errors in DSC scans on the prediction of the average density of nuclei in polymers crystallized under quiescent conditions, THERMOCHIM ACTA 391 (1-2): 97-106 (2002). 3. Martins JA, Pinto JJCC, True sample temperatures in isothermal differential scanning calorimetry scans and their effect on the overall polymer crystallization kinetics, J APPL POLYM SCI 91 (1): 125-131 (2004). 4. Zhang W, Martins JA, The temperature calibration of a parallel plate rheometer and evaluation of the thermal lags during polymer solidification, THERMOCHIM ACTA 413 (1-2): 101-110 (2004). 5. Malheiro MJA, Martins JA, Cruz Pinto JJC, Evaluation of the calibration errors on cooling of a DSC with different sets of standard metals, THERMOCHIM ACTA, 420: 155-161 (2004). C. Shear-induced crystallization. 1. Martins JA, Zhang W, Carvalho V, Brito AM, Soares FO, Evaluation of the sample temperature increase during the quiescent and shear-induced isothermal crystallization of polyethylene, POLYMER 44 (26): 8071-8079 (2003). 2. Martins JA, Zhang W, Brito AM, et al. Isothermal and nonisothermal crystallization of polymers: Analysis with a shear differential thermal analyzer, REVIEW OF SCIENTIFIC INSTRUMENTS 76 (10): Art. No. 105105 OCT 2005. D. Other areas 1. Martins JA, Seixas J, Oliveira MJ, Maio AM, Pouzada AS, Optical properties of injection-molded polystyrene scintillators. II. Distribution of dopants, J APPL POLYM SCI 88 (11): 2714-2718 (2003). 2. Martins JA, Seixas J, Silva J, Esteves V, Oliveira MJ,Gomes J, Maio A, Pouzada AS, Optical properties of injection-molded polystyrene scintillators. I. Processing and optical properties, J APPL POLYM SCI 88 (11): 2706-2713 (2003). 3. Domingues MSQ, Gomes JINR, Martins JA, Dyeing of PA6.6 fibers - Effect of solvent and temperature on thermal properties, J THERM ANAL CALORIM 74 (3): 749-759 (2003).