Jobs in aeronautics also pay less than other engineering jobs, which may be why nearly half of engineers who major in aeronautics work in another industry, according to data from the American Institute of Aeronautics and Astronautics. Two other factors will influence the number of aeronautics job opportunities.
The basic binding materials in plastic are resins, which undergoes polymerization and condensation reactions during the preparation of plastic. There are two types of plastics, thermoplastics and thermoset plastics. Examples of thermoplastics include polythene (PE), polypropylene (PP), polyvinyl chloride (PVC), polytyrene (PS), nylons, and polytetrofluoro ethylene (PTFE or Teflon). Examples of thermoset plastics include phenolic resins, amino resins, polyester resins, silicon resins, epoxy resins, and polyurethanes. This handbook discusses the types, properties, uses, and advantages of thermoset plastics.
There are, however, some plastics that cannot be recycled. These plastics are called thermosets, which are plastics that cannot return to their original form. The best example of this type of plastic is Phenolic which was the first commercially available plastic back in 1907, and was originally called Bakelite.his plastic is primarily used for soft drink bottles. It is the easiest to recycle plastic and can be reground and reused time and time again. The plastic with the number 2 symbol on it is HDPE which is a plastic primarily used for grocery bags, milk jugs and laundry detergent bottles.