In the production of polyethylene foams by extrusion with alkanes as a blowing agent, significant changes in the dimensions of extruded products are encountered. The dimensional stability of a foam with a structure of closed cells is improved by blending the polymer with small amounts of a low molecular weight additive. It is believed that the dimensional stability is related to the ratio of th...

Polyurethane foam (PUF) is an outstanding material for various applications, which is manufactured by propelling liquid isocyanate-polyol mixture to form foams in the presence of blowing agent. In order to reduce the ozone depletion and environmental pollution from organic blowing agents, waterblown PU foams were prepared with various water levels (311phr), and the effects of water level on mec...

M. Saternus, T. Merder, J. Pieprzyca: Silesian University of Technology, Department of Metallurgy, Katowice, Poland The research which visualizes the process of argon blowing through modelling agent in continuous URC-7000 reactor was carried out. Physical model was built according to the theory of similarity. Additionally, the measurements of modelling agent c onductivity w ere done . A s a c o...

This work reports a novel thick-foam ferroelectret which is designed and engineered for energy harvesting applications. We fabricated this ferroelectret foam by mixing a chemical blowing agent with a polymer solution, then used heat treatment to activate the agent and create voids in the polymer foam. The dimensions of the foam, the density and size of voids can be well controlled in the fabric...

This paper presents a discussion on whistle-blowing and take the view that whistle-blowing is an important fraud detection technique. A discussion of some factors that influence the whistle-blowers’ incentive to blow the whistle or to remain silent in the face of persuasive fraud red flags, is also presented. The paper suggests that the tradeoff between the cost and benefit of whistle-blowing m...

In foaming processes, the blowing agent has a significant influence on material behaviour and necessary processing parameters. Low-density polypropylene foam sheets are usually produced with aliphatic hydrocarbons or alkanes as physical agent. Due to safety precautions environmental impact, there is great interest in using alternative agents such CO 2 . The sole use of often leads corrugation, ...