1. Cov nyhuv ntawm longitudinal stretching
Cov resin dhau los ntawm kev sib xyaw, extrusion thiab calendering cov txheej txheem thiab nthuav tawm ib feem ntawm cov yeeb yaj kiab vim yog qhov tsim ntawm fibrillated nta thaum lub sij hawm calendering. Thaum lub sij hawm longitudinal stretching, cov polycrystalline aggregates pib mus rau hauv daim ntawv fibrils, uas yog parallel mus rau stretching kev taw qhia. Qhov hla ntawm cov fibrils yog dav thiab nyias, thiab qhov dav dav yog li 100 nm, thaum cov fibrils me me yog 0.5 txog 1.0 nm.
2. Kev cuam tshuam ntawm kab rov tav nthuav dav
Lub transverse stretching theem yog tswj cov qauv microporous thiab thickness ntawm zaj duab xis. Nyob rau hauv cov txheej txheem transverse stretching, txhua feem ntawm zaj duab xis raws li transverse stretching kev taw qhia yog tsis uniformly stretched nyob rau hauv lub transverse kev taw qhia, thiab transverse stretching yog ib tug non-uniform stretching txheej txheem. Piv nrog rau ob sab ntawm zaj duab xis, qhov sib piv ntawm qhov nruab nrab yog qhov me me, thiab qhov tsis sib xws ntawm qhov kev sib tw ua rau lub qhov pore me me thiab qhov porosity tsawg nyob rau hauv nruab nrab cheeb tsam nyob rau hauv transverse stretching kev taw qhia ntawm zaj duab xis, thaum lub pore loj. thiab porosity ntawm ob sab yog loj. Qhov sib txawv ntawm cov qauv microporous nyob rau hauv cov kev taw qhia transverse ntawm zaj duab xis yuav cuam tshuam rau cov dej tsis zoo thiab noo noo permeability ntawm cov dej tsis zoo thiab breathable membrane thiab nws cov ntaub laminated.
Cov txheej txheem xws li longitudinal stretching ratio thiab stretching kub yog tsau, thiab transverse stretching ratio yog hloov. Cov zaj duab xis porosity thiab uniform pore loj nce nrog qhov nce ntawm transverse stretching yam. Nyob rau tib lub sij hawm, fibrils parallel mus rau qhov kev taw qhia no kuj muaj nyob rau hauv lub transverse stretching kev taw qhia.
3. Kev cuam tshuam ntawm kab rov tav nthuav dav
Lub lateral expansion ceev kuj muaj feem xyuam rau cov qauv zaj duab xis. Qhov siab dua qhov kev nthuav dav ntawm sab nraud, qhov loj dua qhov porosity, thaum lub cev pore loj txo me ntsis. Thaum lub sij hawm ceev nrooj stretching, qhov ntev ntawm lub thicker cheeb tsam ntawm cov zaj duab xis yog me me, thaum lub low-speed stretching tshwm sim nyob rau hauv ntau elongation ntawm cov npoo ntawm zaj duab xis, uas tsis zoo stretch lub hauv paus cheeb tsam ntawm lub hauv paus daim kab xev, yog li qhov ntev ntawm cov yeeb yaj duab. thaj tsam tuab yog loj. Nyob rau hauv qhov sib txawv stretching tus nqi, tus nqi stretching cuam tshuam rau kev hloov ntawm kev ntxhov siab. Thaum lub sij hawm high-speed stretching, vim strain hardening thiab tus nqi-rhiab nyhuv, lub thickness ntawm lub thinned cheeb tsam yuav nce, thiab cov kev nyuaj siab tshwm sim los ntawm lub nruam deformation yuav nce, thiab cov kev ntxhov siab yuav sai sai hloov mus rau hauv nruab nrab ntawm lub baseband. . Lub thickness thiab microporous qauv ntawm zaj duab xis nyob rau hauv lub transverse kev taw qhia yuav zoo ib yam;