Cov yam ntxwv tseem ceeb thiab cov qauv molecular ntawm cov yas

Cov khoom sib txawv ntawm cov yas txiav txim siab nws siv hauv kev lag luam.Nrog rau kev nce qib ntawm thev naus laus zis, kev tshawb fawb txog kev hloov kho yas tsis tau tso tseg.Dab tsi yog cov yam ntxwv tseem ceeb ntawm cov yas?
1. Feem ntau cov yas yog lub teeb hauv qhov hnyav, tshuaj lom neeg ruaj khov, thiab yuav tsis xeb;
2. Kev cuam tshuam zoo;
3. Nws muaj pob tshab zoo thiab hnav tsis kam;
4. Zoo rwb thaiv tsev thiab thermal conductivity tsawg;
5. Lub formability thiab colourability yog zoo, thiab tus nqi ua yog tsawg;
6. Cov yas feem ntau muaj cov cua sov tsis zoo, siab thermal expansion tus nqi thiab yooj yim rau hlawv;
7. Tsis zoo seem stability thiab yooj yim rau deform;
8. Cov plastics feem ntau muaj qhov tsis zoo ntawm qhov kub thiab txias, ua rau qhov kub thiab txias thiab yooj yim rau hnub nyoog;
9. Qee cov yas yog yooj yim soluble hauv cov kuab tshuaj.
10. Cov yas tuaj yeem muab faib ua ob pawg: thermosetting thiab thermoplastic.Lub qub tsis tuaj yeem hloov kho rau kev siv, thiab tom kawg tuaj yeem rov tsim dua.Thermoplasticity muaj lub cev loj elongation, feem ntau 50% mus rau 500%.Lub zog tsis sib txawv kiag li linearly ntawm txawv elongations.

Muaj ob hom qauv molecular ntawm plastics: thawj yog cov qauv linear, thiab cov polymer compound nrog cov qauv no hu ua linear polymer compound;Qhov thib ob yog lub cev qauv, thiab cov polymer compound nrog cov qauv no yog hu ua compound.Nws yog ib qho khoom sib xyaw polymer.Qee cov polymers muaj branched chains, hu ua branched polymers, uas belongs rau ib tug linear qauv.Txawm hais tias qee cov polymers muaj kev sib txuas ntawm cov molecules, tab sis tsawg dua kev sib txuas, hu ua network qauv, koom nrog lub cev qauv.
Ob tug qauv sib txawv, uas qhia ob yam khoom sib txawv.Linear qauv, cua sov tuaj yeem yaj, tsawg hardness thiab brittleness.Lub cev qauv muaj ntau dua hardness thiab brittleness.Plastics muaj ob lub qauv ntawm cov polymers, thermoplastics ua los ntawm linear polymers, thiab thermosetting yas ua los ntawm tej polymers.