| 摘要 |
<p>Aramids which after drawing have high tensile strengths and tensile moduli are made from units derived from selected 2,2'-disubstituted-4,4'-diaminobiphenyls, p-phenylenediamine, oxydianiline and terephthalic acid. Such aramids can be drawn at least 1.5%, which results in the drawn aramid having significant crystallinity and higher tensile strength. The aramids are useful for ropes and composites. The 2,2' substituents may be chlorine, bromine or methyl.</p> |
