Cov qauv molecular ntawm roj hmab muaj cov yam ntxwv hauv qab no:
① Cov molecule yog cov saw hlau ntev uas tsim los ntawm cov khoom siv rov ua dua (chain ntu). Cov saw hlau molecular yog hloov tau thiab nws cov ntu ntu yog cov nquag nquag. Cov iav hloov pauv kub (Tg) qis dua chav sov.
(2) qhov kev nyiam ntawm kev sib cuam tshuam (van der Waals quab yuam) yog me me, nyob rau hauv ib txwm muaj (tsis muaj kev ntxhov siab) yog amorphous, cov molecules yooj yim txav mus rau ib leeg;
(3) Qee qhov ntawm cov molecules tuaj yeem txuas tau los ntawm kev sib txuas ntawm chemical crosslinking lossis lub cev entanglement, tsim cov qauv peb-dimensional mesh molecular kom txwv cov haujlwm loj ntawm tag nrho cov macromolecular saw. Los ntawm qhov pom ntawm microscopic, cov atoms thiab saw ntu ntawm cov saw ntev ntev uas ua cov roj hmab yog nyob rau hauv qhov kev txav mus tas li vim thermal co, uas ua rau tag nrho cov molecule coj mus rau ib qho tsis sib xws ntawm cov kab sib txuas, thiab qhov kev ncua deb ntawm cov molecule. ob qhov kawg ntawm cov molecule yog ntau me dua qhov ncaj ntev. Ib daim ntawm unstretched roj hmab yog zoo li ib tug tangle ntawm coiled, threadlike molecules. Thaum cov roj hmab tsis raug rau sab nraud quab yuam, tus nqi entropy ntawm lub xeev undeformed yog qhov loj tshaj plaws. Thaum cov roj hmab yog stretched, nws cov molecules yog teem nyob rau hauv kab sib txawv degrees nyob rau hauv kev coj ntawm stretching. Kev ua haujlwm yuav tsum tau ua kom muaj kev taw qhia no, yog li cov roj hmab tiv taus kev ncab. Thaum lub zog sab nraud raug tshem tawm, cov roj hmab yuav thim rov qab mus rau lub xeev ntawm qhov siab tshaj plaws entropy. Yog li ntawd, cov elasticity ntawm cov roj hmab feem ntau yog los ntawm "entropy elasticity" ntawm kev hloov ntawm entropy hauv lub system.
