Spectra polyolefin fiber

Among the spectrum of melt-spinnable fibers such as polyolefins and nylons, PET stands at the upper end in terms of crystalline melt temperature and glass transition temperature. This provides superior dimensional stability for applications where moderately elevated temperatures are encountered, e.g. in automobile tires or in home laundering and drying of garments. The high thermal stability results from the aromatic rings that hinder the mobility of the polymer chain. 

Figure 11.10 FTIR spectrum of defect in a polyolefin film. The spectrum indicates that the gel is cellulosic fiber and degraded PE resin...

Polyethylene (PE) and polypropylene (PP) exemplify a class of materials called polyolefins. Composites based on these resins are relatively new by the standards of those early materials of construction. Recent efforts to use these types of materials combine inherent cost-effectiveness with a wide spectrum of end-use applications as film, fiber, and moldings. The impetus for this remarkable development is attributed to the ease of polyolefin manufacture with effective production and purification of the monomers from a variety of sources, ongoing improvements of the catalyst, and large well-controlled polymerization units. Consequently, a strong market demand for good performance and cost-effective materials have spurred a multibillion dollar industry. 

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