Nano-scale Flexible Interphase in a Glass Fiber/Epoxy Resin System Obtained by Admicellar Polymerization

Organosilane coupling agents are widely used in the composites industry to improve the wetting of inorganic reinforcements by low surface energy resins. An increased wettability is often a harbinger of better mechanical properties in a structural composite. Silane coatings effectively increase the spreading of liquid matrixes over glass reinforcement by altering the surface energetics of glass, not by extensive coverage, but by eradication of the high-energy sites present in the oxide surface. Commercial sizings often applied to glass fibers contain up to 10% of the active silane agent, while the remaining 90% is a mixture of lubricants, surfactants, anti-stats, and film formers. Recent investigations have demonstrated that non-reactive components tend to remain in high concentrations within the interphase, thus weakening the resin network crosslink density and increasing the potential for water ingress. Further, sizing formulations are proprietary and designed for specific resin system, which make them expensive, consequently limiting their widespread use. In this paper, admicellar polymerization, a versatile technique to prepare elastomeric thin films of styrene-isoprene copolymer and polystyrene on the surface of random glass-fiber mats is presented. This hydrophobic coating of monolayer thickness applied to the glass fibers is not expected to disrupt the matrix cross-linking reaction; and due to its higher elastic modulus, is believed to cause a change in the stress distribution along the fiber length. Admicellar-modified reinforcements were impregnated with an epoxy resin system: EPON 815C/EPICURE 3232, and molded by Resin Transfer Molding (RTM) into disk shaped parts. Tensile strength, stiffness and interlaminar shear strength (ILSS) were measured for the flexible interphase composites, and compared to parts containing commercially sized and bare fibers. Void fraction, void size and shape distributions, as well as water diffusivity were investigated for each system.YesPeer reviewed and presented at the 18th International Conference of the Polymer processing Society

Simulation training for vascular access interventions

Training and learning in the field of access for dialysis, including peritoneal and hemodialysis and access for oncologic patients, is well suited for the use of simulators, simulated case learning, and root cause analysis of adverse outcomes and team training. Simulators range over a wide spectrum from simple suture learning devices, inexpensive systems for venous puncture simulation, such as a turkey breast or leg with a pressurized tunneled rubber or graft conduit, to sophisticated computer designed simulators to teach interventional procedures such as vascular access angiogram, balloon angioplasty and stent placing. Team training capitalizes on the principles used in aviation, known as Crew Resource Management (CRM) or Human Factor (HF). The objectives of team training are to improve communication and leadership skills, to use checklists to prevent errors, to promote a change in the attitudes towards vascular access from learning through mistakes in a non-punitive environment, to impacting positively the employee performance and to increase staff retention by making the workplace safer, more efficient and user-friendly