Polymeric fibers with unusual characteristics

Efforts to improve the compressive properties of rigid-rod polymer fibers have involved introduction of cross-linking in the transverse direction (Bhattacharya, 1989 Spillman et al, 1993) and coating the fiber surface with a thin layer of a high modulus material (McGarry and Moalli, 1991,1992). 

Polymeric fibers can have some very unusual characteristics. We describe some of these. 

In a multifilament yam or in a braided fabric, normal (i.e. in the radial direction) frictional force holds the fibers together. Such an interfiber friction is desirable if we wish to have strong yams and fabrics. However, there eire situations where we would like to have a smooth fiber surface. For example, in a yam passing round a guide, a smooth fiber surface is desirable. If the fiber surface is 

Normally one thinks of polymers and polymeric fibers as electrical insulators. However, there is some laboratory-scale work that has resulted in electrically conducting PBZT and PPTA fibers, which are based on rigid-rod polymers. The trick to impart conductivity is to mix metallophthalocyanine into the spinning dope (Wynne et al., 1985 Polls et al., 1989). However, the mechanical properties of these fibers deteriorate with increasing content of metallophthalocyanine. 

There are some unusual applications that involve a combination of fibers. Consider the problem of static electricity that is generated from fabric-to-fabric or fabric-to-surface rubbing. It is generally thought of as a minor nuisance. It 

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