Dab tsi yog qhov txawv ntawm thermoplastics thiab thermosets

Thermoplastics thiab thermosets yog ob hom polymers uas muaj cov khoom sib txawv thiab kev coj cwj pwm. Qhov sib txawv tseem ceeb ntawm ob qhov lus dag hauv lawv cov lus teb rau cov cua sov thiab lawv lub peev xwm los hloov kho. Hauv tsab xov xwm no, peb yuav tshawb txog qhov sib txawv ntawm cov thermoplastics thiab thermosets kom ntxaws.

Thermoplastics

Thermoplastics yog cov polymers uas tuaj yeem yaj thiab hloov pauv ntau zaus yam tsis muaj kev hloov pauv tshuaj lom neeg tseem ceeb. Lawv muaj ib tug linear los yog branched qauv, thiab lawv cov polymer chains yog tuav ua ke los ntawm qaug zog intermolecular rog. Thaum rhuab, cov thermoplastics soften thiab ua ntau malleable, cia lawv molded rau hauv ntau yam duab. Piv txwv ntawm thermoplastics muaj xws li polyethylene, polypropylene, thiab polystyrene.

Teb rau Kub

Thermoplastics soften thaum rhuab thiab tuaj yeem hloov kho. Qhov no yog vim hais tias cov tsis muaj zog intermolecular rog tuav lub polymer chains ua ke yog kov yeej los ntawm tshav kub, tso cai rau cov chains txav ntau dawb do. Yog li ntawd, cov thermoplastics tuaj yeem yaj thiab hloov pauv ntau zaus yam tsis muaj kev hloov pauv tshuaj tseem ceeb.

Kev Hloov Siab

Cov thermoplastics tuaj yeem yaj thiab hloov pauv ntau zaus. Qhov no yog vim hais tias cov saw hlau polymer tsis muaj tshuaj lom neeg sib raug zoo rau ib leeg, thiab cov tub rog sib txuas uas tuav lawv ua ke tsis muaj zog. Thaum cov thermoplastic txias, cov chains rov ua kom muaj zog, thiab cov rog intermolecular rov tsim dua.

Tshuaj Txheem

Cov thermoplastics muaj cov qauv linear lossis branched, nrog cov tsis muaj zog intermolecular rog tuav lawv cov saw hlau polymer ua ke. Cov saw hlau tsis muaj tshuaj lom neeg sib raug zoo rau ib leeg, thiab lub zog intermolecular kuj tsis muaj zog. Qhov no tso cai rau cov saw hlau txav tau yooj yim dua thaum rhuab, ua rau cov thermoplastic ntau malleable.

Neeg kho tshuab Properties

Thermoplastics feem ntau muaj qis zog thiab nruj piv rau cov thermosets. Qhov no yog vim hais tias cov saw hlau polymer tsis muaj tshuaj lom neeg sib raug zoo rau ib leeg, thiab cov tub rog sib txuas uas tuav lawv ua ke tsis muaj zog. Yog li ntawd, cov thermoplastics hloov tau yooj yim dua thiab muaj qhov qis dua ntawm elasticity.

daim ntawv sau npe

Cov thermoplastics feem ntau yog siv rau hauv cov khoom uas xav tau kev hloov pauv, xws li cov khoom ntim, cov kav dej, cov txheej txheem thermoplastic thiab automotive Cheebtsam. Lawv kuj tau siv rau hauv cov ntawv thov uas xav tau kev pom tseeb, xws li ntim khoom noj thiab khoom siv kho mob.

Thermosets

Thermoset polymers tau txais tshuaj lom neeg cov tshuaj tiv thaiv thaum kho, uas irreversibly hloov lawv mus rau hauv ib tug hardened, crosslinked xeev. Cov txheej txheem no yog hu ua crosslinking lossis curing, thiab nws feem ntau tshwm sim los ntawm tshav kub, siab, lossis qhov sib ntxiv ntawm tus neeg sawv cev kho. Thaum kho tau, cov thermosets tsis tuaj yeem yaj lossis hloov pauv yam tsis muaj kev cuam tshuam loj. Piv txwv ntawm cov thermosets muaj xws li epoxy, phenolic, thiab polyester resins.

Teb rau Kub

Cov thermosets tau txais cov tshuaj tiv thaiv tshuaj thaum lub sijhawm kho, uas irreversibly hloov lawv mus rau hauv lub hardened, crosslinked xeev. Qhov no txhais tau hais tias lawv tsis soften thaum rhuab thiab tsis tuaj yeem hloov kho. Thaum kho tau lawm, cov thermosets yog qhov ruaj khov thiab tsis tuaj yeem yaj lossis hloov kho yam tsis muaj kev cuam tshuam loj.

Kev Hloov Siab

Cov thermosets tsis tuaj yeem rov ua dua lossis rov ua dua tom qab kho. Qhov no yog vim cov tshuaj tiv thaiv uas tshwm sim thaum lub sij hawm kho irreversibly transforms cov polymer chains mus rau hauv ib tug hardened, crosslinked xeev. Thaum kho, lub thermoset yog ruaj khov thiab tsis tuaj yeem yaj lossis rov ua dua yam tsis muaj kev cuam tshuam loj.

Tshuaj Txheem

Cov thermosets muaj cov qauv sib txuas, nrog cov kev sib cog lus muaj zog ntawm cov saw hlau polymer. Cov chains yog chemically bonded rau ib leeg, thiab cov intermolecular rog tuav lawv ua ke muaj zog. Qhov no ua rau lub thermoset nruj dua thiab tsis yooj yim dua li cov thermoplastic.

Neeg kho tshuab Properties

Thermosets, ib zaug kho, pom qhov zoo ntawm qhov ruaj khov, siab zog, thiab tsis kam mus rau tshav kub thiab tshuaj. Qhov no yog vim qhov crosslinked qauv ntawm lub thermoset muab cov qib siab ntawm rigidity thiab lub zog. Lub zog covalent bonds ntawm lub polymer chains kuj ua rau lub thermoset ntau resistant rau tshav kub thiab tshuaj.

daim ntawv sau npe

Cov thermosets yog siv rau hauv cov ntawv thov uas xav tau lub zog siab thiab ua haujlwm ntev, xws li cov khoom siv dav hlau, cov khoom siv hluav taws xob, thiab cov khoom sib xyaw. Lawv kuj tseem siv tau rau hauv cov ntawv thov uas yuav tsum tau ua kom tsis muaj cua sov thiab tshuaj lom neeg, xws li coatings, adhesives, thiab sealants.

Kev sib piv ntawm Thermoplastics thiab Thermosets

Qhov sib txawv ntawm cov thermoplastics thiab cov thermosets tuaj yeem ua tiav raws li hauv qab no:

• 1. Teb rau cov cua sov: Thermoplastics soften thaum rhuab thiab tuaj yeem hloov kho, thaum cov thermosets tau txais cov tshuaj tiv thaiv thiab ua kom tawv tawv mus tas li.
• 2. Kev thim rov qab: Cov thermoplastics tuaj yeem yaj thiab hloov pauv ntau zaus, thaum cov thermosets tsis tuaj yeem rov ua dua lossis rov ua dua tom qab kho.
• 3. Cov qauv tshuaj: Thermoplastics muaj cov qauv linear lossis branched, nrog cov tsis muaj zog intermolecular rog tuav lawv cov saw hlau polymer ua ke. Cov thermosets muaj cov qauv sib txuas, nrog cov kev sib cog lus muaj zog ntawm cov saw hlau polymer.
• 4. Mechanical zog: Thermoplastics feem ntau muaj qis zog thiab nruj piv rau cov thermosets. Thermosets, ib zaug kho, pom qhov zoo ntawm qhov ruaj khov, siab zog, thiab tsis kam mus rau tshav kub thiab tshuaj.
• 5. Kev siv: Cov thermoplastics feem ntau yog siv rau hauv cov khoom uas xav tau kev hloov pauv, xws li cov khoom ntim, cov kav dej, thiab cov khoom siv hauv tsheb. Cov thermosets yog siv rau hauv cov ntawv thov uas xav tau lub zog siab thiab ua haujlwm ntev, xws li cov khoom siv dav hlau, cov khoom siv hluav taws xob, thiab cov khoom sib xyaw.

xaus

Hauv kev xaus, thermoplastics thiab thermosets yog ob hom polymers uas muaj cov khoom sib txawv thiab kev coj cwj pwm. Qhov sib txawv tseem ceeb ntawm ob qhov lus dag hauv lawv cov lus teb rau cov cua sov thiab lawv lub peev xwm los hloov kho. Thermoplastics tuaj yeem yaj thiab hloov pauv ntau zaus yam tsis muaj kev hloov pauv tshuaj lom neeg tseem ceeb, thaum cov thermosets tau txais cov tshuaj tiv thaiv tshuaj thaum kho, uas irreversibly hloov lawv mus rau hauv lub hardened, crosslinked xeev. Kev nkag siab qhov sib txawv ntawm cov thermoplastics thiab thermosets yog qhov tseem ceeb rau kev xaiv cov khoom tsim nyog rau daim ntawv thov.