Hom Aramid Fibers

Aramid fibers tuaj nyob rau hauv ntau hom, feem ntau categorized rau hauv ob pawg loj: tag nrho cov aromatic polyamide fibers thiab heterocyclic aromatic polyamide fibers. Kev faib tawm ntxiv ua rau peb hom tshwj xeeb: *ortho*-aramid, *para*-aramid (PPTA), thiab *meta*-aramid (PMTA). Tam sim no, cov khoom lag luam uas tau ua tiav kev lag luam- nplai ntau lawm yog feem ntau *meta*-aramid thiab *para*-aramid. Thawj qhov sib txawv ntawm ob pawg no yog nyob rau hauv txoj haujlwm sib txuas ntawm amide linkage txheeb ze rau carbon atoms ntawm lub nplhaib benzene.

*Para*-aramid, tseem hu ua poly(*p*-phenylene terephthalamide) (PPTA), raug xa mus rau hauv Suav teb raws li Aramid 1414. Cov yam ntxwv ntawm cov fiber ntau yog tias ntau dua 85% ntawm amide linkages nyob rau hauv nws cov saw molecular yog ncaj qha txuas mus rau aromatic rings. Qhov tseem ceeb, nws yog thawj fiber ntau hauv ntiaj teb uas tsim los siv ua kua-crystalline polymer spinning thev naus laus zis- qhov kev ua tiav uas tau qhib ib tshooj tshiab hauv kev txhim kho siab - cov khoom siv hluavtaws.

*Meta*-aramid, los yog poly(*m*-phenylene isophthalamide) (PMTA), yog lub npe hu ua Aramid 1313. Cov fiber ntau no muaj npe nrov rau nws qhov tshwj xeeb nplaim taws retardancy, thermal stability, thiab hluav taws xob tsis kam; nws cov qauv molecular muaj amide pawg txuas *meta*-oriented phenyl rings, uas ua rau ib tug linear, zigzag configuration. Cov qauv molecular tshwj xeeb no muab cov khoom zoo ntawm lub cev thiab tshuaj lom neeg rau *meta*-aramid.