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Around the world, concern is growing about the amount of waste rubber going into landfills. Policymakers are encouraging researchers to find innovative ways to recycle this waste. In this study, as part of an effort to recycle waste rubber (EPDMR) as filler in compositions of EPDM, we prepare a terpolymer of ethylenepropylene-diene with 1-dodecanethiol (EPDMSDD). We use it as a compatibilizing agent to improve adhesion and incorporation of the residue (EPDMR) in EPDM/EPDMR blends. We synthesize and characterize EPDMSDD through 13 C-NMR and FTIR spectroscopy. We evaluate the effect of the compatibilizer EPDMSDD using vulcanization parameters, such as optimum cure time, scorch time, and torque. To evaluate its effect on the interaction between EPDMSDD/EPDMR, we carried out mechanical tests of samples with and without EPDMSDD. Our findings show that the tensile strength and elongation increased with the addition of EPDMSDD, indicating a better interaction between EPDMR/EPDM. Tear strength also increased with the presence of EPDMSDD, particularly for the amount of 70 and 80 phr of EPDMR. This suggests a good adhesion between the phases in high amounts of waste. The micrographs of the mixtures revealed that the addition of EPDMSDD improved the dispersion of the EPDMR in the EPDM phase.

Using an experimental design and a multi-measure and multi-informant approach, the current study sought to evaluate the impact of the early developmental prevention program “ZARPAR”—an intervention designed as a social and cognitive skills training program, that seeks to promote children’s behavioral adjustment. A sample of elementary school children (experimental group n = 37; control group n = 66), attending Portuguese schools, was assessed before and 6 months after the intervention on the program’s key-dimensions: behavioral problems, social skills, and executive functioning. Based on parent and teacher reports, the results largely suggested that the intervention had no effect or, for some dimensions, even the existence of negative outcomes. Possible reasons for these results are discussed. The current study highlights that, despite the overwhelmingly positive message about developmental prevention programs, not all interventions work, thus reinforcing the need for rigorous evaluations, in order to enhance the success of future interventions.

This research aimed to explore the direct and indirect effects of students’ school engagement, school climate and parenting practices on youth’s externalizing behaviors. A quantitative methodology with a sample of 183 Portuguese students, aged between 11 and 16 years old, was used. The main results suggested negative associations between externalizing behaviors and higher levels of school engagement and positive school climate. Poor parental supervision, inconsistent discipline and corporal punishment were positively related with externalizing behaviors, contrary to parental involvement and positive parenting that were associated with lower levels of externalizing behaviors. However, negative parenting practices were associated with lower levels of school engagement. Additionally, the results indicated that parenting practices might influence youth’s externalizing behaviors through school engagement.

Taking into consideration the framework of the general theory of crime, research has been exploring the role of low self-control in the explanation of both crime perpetration and personal victimization. Moreover, while several studies have been analysing the role of victimization experiences in the fear of crime, less is known about how an individuals’ fear of crime influences the likelihood of being victimized. Therefore, using a sample of 243 individuals (55.6% women) from the University of Porto, through a self-reported survey, we tested (i) the effects of low self-control on victimization and (ii) the moderating role of fear of crime on the relationship between self-control and victimization. Results showed that low self-control was positively correlated with victimization. It was observed that fear of crime moderated the effect of low self-control on victimization, thus suggesting that the relationship between low self-control and victimization is not observed when fear of crime is high. Implications of the results are discussed.

Homenagem a Cleonice Berardinelli (28/8/1916 – 31/1/2023)

Apresentação à Converência Lusíada 49.