Retention of tenacity

Figure 4 shows the retention of tenacity in percent of the original values compared with another aromatic polyamide, M3P, the polytereph-thalamide of bis(m-aminobenzoyl)m-phenylenediamine (31). 

Figure 4. Retention of tenacity of polymer fibers at elevated temperature...

Figure I. Retention of tenacity (polypropylene. 001-in. oriented film 0.3% LS 45° south...

Anions strongly retained by soils include PO -, AsO -, MoO -, CrO -, and F-. These anions are essential microelements for plants and animals and are present in trace concentrations in the solutions of native soils. Because the amounts and tenacity of soil retention of these ions is so much greater than Cl, NO3, and others, this retention has been misnamed as specific adsorption. These anions are simply... 

The cross-links formed in the molecular structure are key to the superior heat resistance of XLA. As the temperature increases, crystallites gradually disappear and cross-links take over keeping the network structure retention. After cooling down, crystallites will reform. This makes XLA very different from conventional melt-spun fibers, which rely on crystallites for both recovery and heat resistance. Figure 3.2 shows the percent tenacity retention of chlorine-treated XLA elastic fibers and elas-tane fibers evaluated under accelerated conditions. XLA elastic fiber retains more than 80% of the mechanical tenacity up to 40 hours of treatment. However, the mechanical property of elastane quickly deteriorates to 45% of its starting tenacity within only 10 hours. 

It is generally accepted that, all other things being equal, the lower the secondary creep, the better the fiber is in terms of wear, shape retention, and crease resistance. This does not mean that glass, which has no secondary creep, is better in abrasion resistance than high tenacity viscose rayon, which has secondary creep, because the respective energy absorption capacities of these two materials, exclusive of secondary creep, are not equal. Nor does it mean that fibers that exhibit secondary creep are of no value. For fabrics to meet the requirements of wear, crease resistance, and shape retention, the load and extension yield points should not be exceeded during use. 

Morpholine itself has three characteristics which favor its adsorption and retention by paper first, it is an amine, and amines are known to adsorb tenaciously on many surfaces second, it is alkaline and third, it has a mild swelling effect (3) on the less-ordered regions of cellulose. When one considers these characteristics of paper and the known characteristics of morpholine, it is easy to see how paper could bind morpholine with some tenacity. Morpholine is probably adsorbed on the large specific surface of cellulose, and it will certainly react with accessible... 

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