Thermal Properties of Epoxy-Based Adhesive Reinforced With Nano And MicroParticles For In-Situ Timber Bonding
—CB10TSS thixotropic and room temperature cured epoxy based adhesive specially formulated for in-situ bonding of pultruded rod into timber for repair and strengthening of timber structures. The glass transition temperature for CB10TSS is 31.7ºC which considered low for outdoor exposure. Therefore CB10TSS was modified by reinforcing it with nano-and micro-particles and denoted as Nanopox (CB10TSS/nanosilica), Albipox (CB10TSS/liquid rubber) and Timberset (CB10TSS/ceramics). Thermal properties of epoxy adhesives were studied by using dynamic mechanical thermal analysis (DMTA) and differential scanning calorimetry (DSC). Albipox showed significant improvement in the glass transition temperature but Timberset has the highest Tg, due to high modulus of ceramic particles. A second scan for all the adhesives increased Tg which shows that the room temperature cured adhesives are not fully cross-linked. In DSC scan, typical graphs of heat flow versus temperature able to describe more characteristic of the curing behavior such as a sharp and deep endothermic dip at Tg which corresponds to a rearrangement of the molecules and the wide and shallow endothermic dip at around 100°C is associated with moisture in the adhesive.
Thermal properties of amine cured diglycidyl ether of bisphenol A epoxy blended with poly(ether imide)
Thermal properties of an epoxy system containing diglycidyl ether of bisphenol A (DGEBA) and 1,3-bisaminomethylcyclohexane (1,3-BAC) as curing agent modified with poly(ether imide) (PEI) were studied using both dynamic mechanical (DMA) and thermogravimetric (TG) analysis. The effect of thermal degradation in air and in vacuum on the dynamic mechanical and thermogravimetric properties for the DGEBA/1,3-BAC/PEI system was investigated. The results showed that this system can be considered miscible for PEI contents up to 10 phr (phr: number of parts of PEI per hundred parts of the DGEBA epoxy resin), and also that even very small contents of PEI in the blends reduced the thermal stability of the material. Thermal degradation during a short period of time of this material both, in air or in vacuum yields a decrease of thermal stability and an increase of the glass transition temperature with respect to the material without degradation.
Gender Politics and Research: Male and Female Violence in Intimate Relationships
This article reviews a wide range of research reports on male and female violence in intimate relationships and highlights the political nature of domestic violence research. The authors review incidence and prevalence-based research that uses quantitative surveys and illustrate how quantitative, family-focussed researchers tend to ignore the political and social context of domestic violence and the complex issues of gender and power. The authors argue that understanding the complexities of domestic violence requires clear definitions of what constitutes domestic violence and multi-method approaches to research, using a combination of quantitative and qualitative methodologies.