Author : Nicholas Tucker
Publisher :
ISBN 13 :
Total Pages : 303 pages
Book Rating : 4.:/5 (117 download)
Book Synopsis In-shot Material Property Changes from a Reaction Injection Moulding (RIM) Machine by : Nicholas Tucker
Download or read book In-shot Material Property Changes from a Reaction Injection Moulding (RIM) Machine written by Nicholas Tucker and published by . This book was released on 1994 with total page 303 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis describes the development of machine control and data capture techniques on a unique four stream reaction injection moulding (RIM) machine. This multi-RIM machine was then used to investigate techniques with the potential for the production of RIM articles with controlled material property gradients throughout the moulding, or "zoned" articles. The original control computer was replaced with a personal computer and a GPIB interface. The process monitoring sensors - linear potentiometers, thermocouples, & pressure transducers were characterised, and work was started on the examination of the curing process in epoxy resins during and after the moulding process by dielectric (non-flow based) methods. For the production of zoned articles, the apparatus was characterised using a non-reacting liquid (polyol) which is close in rheological character to the experimental reacting systems, namely hard and soft polyurethanes. These polyurethanes were also injected through an in-line rheometer, and in a separate experiment into apparatus to measure the adiabatic temperature rise of the polymerisation reactions. Next, injection lance velocity profiles were altered to change the ratio of reagents between the limits of system stoichiometry. Three lances injecting through a single mixhead were then employed to produce a change in material type during the shot: two different polyols were fired sequentially against a common isocyanate stream. Finally, two mix heads were attached to a single mould, allowing two pairs of lances to inject into the mould during the shot. The changes in property produced by these methods were quantified by non-destructive testing (ultrasound), and by dynamic mechanical thermal analysis (DMTA). Evidence of correlation between the two methods is presented.