Evaluation of the Yield Strength of a Carbon Composite Material Prepared by Wet Lamination and Vacuum Bag Molding

To evaluate tensile strength of the carbon composite material we used method of static tensile test according to the STN EN ISO 6892-1:2010-01 standard. The material for the production samples from the composite material was carbon fabrics KORDCARBON 200g/m2 – Twill weave. KORDCARBON 160g/m2 – Plain weave reinforced with epoxy resin Letoxid PR220+hardener EM315. The carbon composite for the test was prepared by Hand lay-up technology and Vacuum Bag molding method. Orientation to the layer laying direction of the individual samples in the test composite material influences the mechanical properties of the carbon fiber composite material produced by Hand lay-up technology and VMB- Vacuum molding bag method.

The effect of nonwoven structure on thermomechanical properties of feather waste reinforced polyester composite

Natural fibers offer good prospective as reinforcements in polymer composites due to their superior properties, they are preferred over synthetic fibers in various applications such as construction, automotive and aerospace. This experimental study emphasizes the effect of nonwoven structure on the mechanical, thermal and biodegradability properties of feathers nonwoven reinforced polyester composite. Vacuum molding method was adopted for manufacturing of the biocomposites with two contents of polyester resin (30% and 50%) and different composition of nonwovens. As a result, the morphological analysis revealed excellent compatibility and regular distribution of fiber in the polyester matrix. The thermal conductivity of manufactured composites varies considerably from 0.0378 W/(m•K) to 0.0778 W/(m•K) at 10°C. The origin of the variation of this property is due to differences in composition of nonwovens, densities and the percentage of the resin. After soaking for 240 h, the biodegradability test show that the kinetics of degradation of the composites decreased with the addition of nonwovens. The biodegradability rate was found between 62 to 92% depending on the sample nature. The mechanical results showed that the nonwoven structure clearly affected the performance of the composites. The results obtained from this study can be useful to develop new low cost, sustainable, light product and environmentally friendly materials.

Determining Thermal Conductivity of Small Molecule Amorphous Drugs with Modulated Differential Scanning Calorimetry and Vacuum Molding Sample Preparation

Thermal conductivity is a material specific property, which influences many aspects of pharmaceutical development, such as processing, modelling, analysis, and the development of novel formulation approaches. We have presented a method to measure thermal conductivity of small molecule organic glasses, based on a vacuum molding sample preparation technique combined with modulated differential scanning calorimetry. The method is applied to the two amorphous model compounds indomethacin and celecoxib. The measured values of below 0.2 W/m °C indicate very low thermal conductivity of the amorphous compounds, within the range of organic liquids and low conducting polymers.