Description:
Polyurethane (PU) foams boost a wide micro and macro morphological properties space which enable its use in a wide swath of applications areas. On the one extreme are the hard and brittle closed fine celled rigid PU foams which are used in a variety of heat management (insulations) applications. On the other extreme are soft open celled flexible PU foams which are used in a variety of comfort applications involving seating, bedding and cushioning. A variety of processes are used to produce these various types of polyurethane foams. Rigid polyurethane foams are typically mostly produced by molding processes, although there are some spray applications as well. Flexible polyurethane foams use a wider variety of applications technologies. The slab-stock foams are typically produced by pouring and reacting mixture on a conveyor system on which a very large bun grows as the foaming system is conveyed down the line. Similarly some viscoelastic or memory foams, as well as some high resiliency (HR) foams used for bedding applications are also produced on conveyor systems. On the other hand, a significant portion of both HR and Viscoelastic foams particularly those used for seating, cushioning and other specialized applications are produced by molding processes. All these types of polyurethane foams can undergo SPLITS (tearing) during or shortly after the manufacturing process. Foam splits result in poor foam performance in their various applications and therefore highly undesirable. In rigid foam used for insulation applications, foam splits result in significant deterioration of the insulating property. For flexible foams, splits result in poor durability and load bearing and comfort properties. The root cause of splits in polyurethane foams and how to eliminate them in the production of these foams will be addressed in this Webinar.

Live Webinar Held: 15 June 2021 (Tuesday)

Speaker:
Dr. Bernard E. Obi is a retired dynamic polymers/materials scientist with extensive expertise in cellular materials in general; but particularly in polyurethane foams processes and applications. He has extensive expertise in both rigid and flexible polyurethane foams. Within the flexible PU foams space, the expertise encompass high resiliency (HR), slab-stock and viscoelastic or memory foams. He earned a Ph.D. in chemical engineering and worked for The Dow Chemical Company from July 1985 to July 2015. Apart from polyurethanes technology; he also has significant expertise in free radical dispersion/suspension polymerization, surface and interfacial science, micro & macro-structure-property-performance relationships, materials development, composites, elastomers and rubbers. He authored a text book on Polymeric Foams Published December 7th 2017 by Elsevier Publishers. Dr. Obi operates his consulting company (PolyFoam Consulting LLC) out of the Houston area in Texas USA, and is engaged in providing consulting services to the polymeric foams industries and businesses.

Description:
Cellular materials are solid foams. They are often produced to take advantage of the properties of the solid material whilst at the same time taking advantage of their light-weighting characteristics. The light weight enables their insulation performance since gas is a poorer thermal conductor than solids. This Webinar explores the various technologies for producing cellular plastics (polymeric foams) from various polymer classes. The Webinar will cover aspects of foaming both thermoplastics and thermoset polymers. Thermoplastic polymers are those which are converted to foams starting from fully formed polymers which are processed through softening (melting or devitrification) and then followed by foaming. The end of foaming is accomplished by freezing the cellular structure through recrystallization or vitrification. Thermosetting polymers are those which start from liquid monomeric raw materials which undergo cross-linking chemical reactions to form a solid polymer. The foaming process happens simultaneously with the cross-linking reactions. The KnowHow Webinar will highlight the advantages and disadvantages encountered in foaming thermoplastic and thermoset polymers.

Live Webinar Held: 24 August 2021 (Tuesday)

Speaker:
Dr. Bernard E. Obi is a retired dynamic polymers/materials scientist with extensive expertise in cellular materials in general; but particularly in polyurethane foams processes and applications. He has extensive expertise in both rigid and flexible polyurethane foams. Within the flexible PU foams space, the expertise encompass high resiliency (HR), slab-stock and viscoelastic or memory foams. He earned a Ph.D. in chemical engineering and worked for The Dow Chemical Company from July 1985 to July 2015. Apart from polyurethanes technology; he also has significant expertise in free radical dispersion/suspension polymerization, surface and interfacial science, micro & macro-structure-property-performance relationships, materials development, composites, elastomers and rubbers. He authored a text book on Polymeric Foams Published December 7th 2017 by Elsevier Publishers. Dr. Obi operates his consulting company (PolyFoam Consulting LLC) out of the Houston area in Texas USA, and is engaged in providing consulting services to the polymeric foams industries and businesses.

Description:
Thermosetting polymers are those which start from liquid monomeric raw materials, and undergo cross-linking chemical reactions to form a solid polymer. The foam expansion reaction which is called the blowing reaction is usually relatively very fast. The foam expansion process is typically completed between 60 to 90 seconds in most thermosets foaming processes. The gelling reactions which build polymer structure, hardness and strength takes relatively long time to complete, typically requiring several hours for completion. The purpose of the fast blowing expansion reaction is to minimize drainage which leads to foam instabilities and poor foam quality or in the worse case complete foam collapse. Thus the need to expand quickly has to be balanced with the equal need to polymerize (i.e. gelling reaction) quickly enough to stabilize the foam, whilst not too fast to retard both the foam expansion and cell opening for flexible foams. In addition to the balanced gelling reaction, surface active agents are typically used to provide the complex interfacial phenomena that provide stabilization in foaming processes that begin from the liquid state. The Webinar will highlight the complexities encountered in production of thermosetting polymeric foams, including the role of surface active agents, the balance of blowing-to-gelling reaction to control both polymer and cellular properties.

Live Webinar Held: 26 October 2021 (Tuesday)

Speaker:
Dr. Bernard E. Obi is a retired dynamic polymers/materials scientist with extensive expertise in cellular materials in general; but particularly in polyurethane foams processes and applications. He has extensive expertise in both rigid and flexible polyurethane foams. Within the flexible PU foams space, the expertise encompass high resiliency (HR), slab-stock and viscoelastic or memory foams. He earned a Ph.D. in chemical engineering and worked for The Dow Chemical Company from July 1985 to July 2015. Apart from polyurethanes technology; he also has significant expertise in free radical dispersion/suspension polymerization, surface and interfacial science, micro & macro-structure-property-performance relationships, materials development, composites, elastomers and rubbers. He authored a text book on Polymeric Foams Published December 7th 2017 by Elsevier Publishers. Dr. Obi operates his consulting company (PolyFoam Consulting LLC) out of the Houston area in Texas USA, and is engaged in providing consulting services to the polymeric foams industries and businesses.

Description:


Live Webinar Held: 08 December 2021 (Wednesday)

Speaker:
Dr. Bernard E. Obi is a retired dynamic polymers/materials scientist with extensive expertise in cellular materials in general; but particularly in polyurethane foams processes and applications. He has extensive expertise in both rigid and flexible polyurethane foams. Within the flexible PU foams space, the expertise encompass high resiliency (HR), slab-stock and viscoelastic or memory foams. He earned a Ph.D. in chemical engineering and worked for The Dow Chemical Company from July 1985 to July 2015. Apart from polyurethanes technology; he also has significant expertise in free radical dispersion/suspension polymerization, surface and interfacial science, micro & macro-structure-property-performance relationships, materials development, composites, elastomers and rubbers. He authored a text book on Polymeric Foams Published December 7th 2017 by Elsevier Publishers. Dr. Obi operates his consulting company (PolyFoam Consulting LLC) out of the Houston area in Texas USA, and is engaged in providing consulting services to the polymeric foams industries and businesses.