Estudo da cinética de degradação da resina benzoxazina e seus compósitos nanoestruturados

The benzoxaxine resin is a new class of thermoset phenolic resin, which is presenting, in the lasts decades, a great application in the aircraft industry due mainly to its excellent mechanical and thermal properties. This resin associates the mechanical properties of epoxy resin with the thermal and flame retardant properties of phenolic resin. In this context, they are considered polymers of high performance and they are excellent candidates to replace the current thermoset matrices used in the processing of high performance composites. Thus, in this study nanostructured composites Benzoxazine/CNT were produced at different concentrations of functionalized and non-functionalized CNT (0,1%; 0,5% and 1,0% w/w). The thermal stability of the benzoxazine resin and its nanostructured composites was studied using thermogravimetry (TGA) and degradation kinetic model Ozawa-Wall-Flynn (O-W-F). The thermal characterization also included differential scanning calorimetry (DSC) and dynamic-mechanical analysis, infrared spectroscopy with Fourier transform (FTIR) and scanning electron microscopy (SEM).The introduction of non-functionalized CNT at low concentrations resulted in nanostructured composites with better thermal properties in relation to the neat resin. For all cases, however, the dispersion of CNT in the matrix was ineffective

O papel dos conflitos no desenvolvimento do juízo moral em crianças da educação infantil

This research sets up as a reflection on the development of moral judgment in children from 04, 05 years of the Early Childhood Education with the main theoretical reference the studies of Jean Piaget (1932/1994) on the subject. To this end, we conducted a case study in order to understand what types of conflicts that arise among children in the school of early childhood education and how the teacher seeks to solve them, or not assisting in promoting the moral autonomy of the small. Behaviors and conflicts observed were described and analyzed by correlating them to the practice of the teacher in the classroom that is the case study. We found that conflicts are avoided and unwanted by the teacher and, when they arise, are quickly resolved through attitudes centered educator without enable dialogue and reflection among the children involved. In this sense, we infer that the teaching practice focused on the development of moral judgment of children showed failure and ineffective. As a result of feedback from the first phase of this research we deem necessary to investigate about the training of teachers of early childhood education in relation to theories that deal with the development of moral judgment in children of this educational stage and identify the implications that such training reflects teacher practices in. We hope that by making such reflection can contribute to the debate on the need to educate morally in early childhood education, whose main objective is to promote the integral development of children