Characterization of the vulcanization process of silicone rubber was achieved through the modeling of dynamic DSC tests. The Kissinger equation and the Kamal-Sourour model were used to determine kinetic parameters that fit the experimental data. The technique allows for the determination of the activation energy through Kissinger's model, which is then used to mathematically determine the other five parameters for the Kamal-Sourour model. This novel technique finds a physically meaningful activation energy. The method generates a single set of parameters that accurately models all scanning rates tested (1, 2.5, 5, and 10 K/min). Five formulations of liquid silicone rubber as well as one solid silicone rubber were tested and modeled. For each material, the models generated fitting parameters that were in agreement with the dynamic DSC scans. The models were used to compare the processing of the liquid and solid silicone rubber. The characterization of both materials demonstrates the lower processing time, temperatures, and energy consumption when processing liquid silicone rubber, as compared to processing of hard silicone rubber. POLYM. ENG. SCI., 47:675

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The use of flipped‐classroom methodology (FC) has increased recently, however, there is a lack of quantitative data on students’ performance. A FC has been applied into a group (80 students) of an obligatory subject of the 2nd course in an Energetic Engineering Bachelor. A second group has been taught with the traditional methodology (72 students) to compare the results. The FC requires students to obtain background knowledge prior to a face‐to face class meeting, and reserves in‐class time for applying knowledge to solve problems. This is the opposite of the traditional lecture‐based classroom, in which students passively attend didactic lectures from the instructor, then study the content and complete assignments after class. The main objectives of this research were to measure the impact of learning (with special attention to really active students), reduce absenteeism, increase exam attendance, and analyze how participating students view their experience with this methodology. The results show that the flipped‐classroom model has a direct impact on student learning (or grades), especially in students with a high degree of involvement (with grades about 1.5 points higher). In addition, the grades standard deviation values were lower (in about one point), ensuring a better general students level. The students are a little reluctant to this new methodology, but thanks to it, they tend to work more (12% of the students work more hours per week), to attend more to class (at least 10% more), and to attend in a higher ratio to exams (around 20%).

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