Thermoset technology

Another area of current research is development of nanocomposites. Incorporation of nanometer-sized fillers in thermosets allows even broader application of thermoset technology. The processing techniques are quite similar to conventional thermosets, but the... 

Years ago, it was predicted (by Herman Mark) that an important advance would come from the combination of thermoplastics technology with thermosetting technology, that is, by use of all four of the strengthening mechanisms named earlier (Figure 1) in a single polymer. Numerous laboratories have worked on various aspects of this approach, but the big breakthrough is apparently still to be made. 

LSRs also have rapid cure cycles and, because post cure is not necessary, finished parts cost less than other thermoset technologies. 

From the point of view of technology, it is convenient to classify polymers as thermosetting and thermoplastic. The former set by chemical crosslinks introduced during fabrication and hence do not change appreciably in their deformability with changes in temperature. Thermoplastics, on the other hand, soften and/or melt on heating and can therefore be altered in shape by heating... 

Some of the most common stabilization—soHdification processes are those using cement, lime, and pozzolanic materials. These materials are popular because they are very effective, plentiful, and relatively inexpensive. Other stabilization—soHdification technologies include thermoplastics, thermosetting reactive polymers, polymerization, and vitrification. Vitrification is discussed in the thermal treatment section of this article and the other stabdization—soHdification processes are discussed below. 

The so-called phenoxy resins were a development of epoxide resin technology which had hitherto been used exclusively in the thermosetting resin field (see Chapter 26). As with the most important epoxide resins they are prepared by reacting bis-phenol A with epichlorohydrin to give the following structure (Figure 21.9) ... 

Parker, F.J, The Status of Thermoset Injection Moulding Today, Progress in Rubber and Plastic Technology, October 1985, vol 1, No 4, pp 22-59. 

Monk, J.F. Thermosetting Plastics - Practical Moulding Technology, George Godwin, London... 

Plastics technology manufacturing handbook and buyers guide , Bill Communications (212-592-6570). Updated annually. The Handbook and Buyers Guide is a comprehensive tool for locating suppliers of primary machinery, materials (thermoplastics and thermosets), auxiliary and secondary equipment and controls, chemicals and additives, and a variety of specialized services. Contains extensive equipment and materials specifications. 

Products Driving forces Threats Wide variety Growth of resin production (PE, PVC, thermosets) New technology (metallocenes) displacing (reducing) needs... 

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