Polymeric tubular structures tubes

Here, we will only focus on synthetic strategies that use polymeric materials. The first approach described is the synthetic chemist s approach to tubular structures. Here, a single polymeric chain is used to fold into a tubular shape. This is achieved via the formation of hollow tube-like helices. The length, i.e. the molecular weight of the polymer chain involved, therefore directly affects the length of the tube-like structure formed. 

Figure 2.1 Polymeric membrane shapes and cross-sectional structures. Tubular membranes are similar to flat sheet membranes because they are cast on a macroporous tube as support. Capillary membranes are hollow fibers with larger diameter, that is, >0.5 mm.

A tubular reactor is similar to a long heat exchanger. The ethylene is circulated through a compressor— the main pressurization of the feed stream is accomplished by a hypercompressor to build up the pressure required for free radical polymerization. This free radical polymerization uses peroxide initiators or oxygen to promote polymerization reactions. The commercial tubular reactors are typically between 1000 and 2500 m long. They consist of high pressure tubes each 10-15-m long in a serpentine like structure within a concrete bay. 

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