Polyurethane (PU) foams are by far the most popular cellular polymer as they cover more than the half of the total foam market.
Depending on if they are either rigid or flexible these widely used materials are mainly employed as thermal insulators, core of sandwich panels (rigid PU foams) or for comfort related applications (mattresses, seats) in the case of flexible foams. The production of PU foams is based on the reactive mixing of polyol and isocyanate. The comprehension of all the aspects related with the formation, structure and properties of these materials is far to be simple.
These webinars are focused on gaining a better understanding of the relationships between chemical composition, foaming mechanisms, structure, and properties of PU foams.
PART 1 – ANALYSIS OF THE RELATIONSHIPS BETWEEN COMPOSITION, STRUCTURE AND PROPERTIES OF PU FOAMS: CONVENTIONAL PROCEDURES
SPEAKER: ESTER LAGUNA-GUTIERREZ
This webinar is focused on analyzing how the cellular structure and properties of PU foams are affected by changing the formulation using different approaches: incorporation of micro and nanoparticles, incorporation of liquid additives, changes in the type of blowing agent, etc.
Different examples are shown in which different strategies are employed with the aim of improving the cellular structure and therefore, the physical properties of the final foams: reduction of thermal conductivity, improvement of mechanical properties, etc.
In this webinar we show how the cellular structure of PU foams can be analyzed in detail by using optical microscopy, SEM and X-Ray Tomography. We also show how the open cell content of both rigid and flexible PU foams can be determined by using gas picnometry. The procedure to determine the extinction coefficient of PU foams by FTIR is also explained.
Finally, we analyze the physical properties of these foams (thermal conductivity and mechanical properties) and the analytical models which allows stablishing a relationship between cellular structure and physical properties.