Video: PVA yog tsim los ntawm dab tsi?
2024 Tus sau: Stanley Ellington | [email protected]. Kawg hloov kho: 2023-12-16 00:17
Polyvinyl cawv tseem hu ua PVOH, PVA , los yog PVAL, yog ib qho hluavtaws polymer uas yog soluble hauv dej. Nws muaj txiaj ntsig zoo hauv kev tsim cov yeeb yaj kiab, emulsifying, thiab muaj cov nplaum zoo. Qhov tseem ceeb raw khoom los tsim PVA yog vinyl acetate monomer. Lub monomer yog tsim los ntawm polymerization ntawm vinyl acetate.
Xav txog qhov no, PVA puas txaus ntshai?
Kev nyab xeeb ntawm PVA yog raws li hauv qab no: (1) mob qhov ncauj toxicity ntawm PVA tsawg heev, nrog LD (50) s nyob rau hauv thaj tsam ntawm 15-20 g / kg; (2) hais lus PVA tsis zoo absorbed los ntawm lub plab zom mov; (3) PVA tsis khaws cia rau hauv lub cev thaum noj tshuaj; (4) PVA tsis mutagenic los yog
PVA puas yog yas? PVA ( polyvinyl cawv ) yog hom 'polymer' lossis yas . Cov npe ntawm ntau tus txiv neej tsim cov polymers, xws li Plexiglass, Teflon thiab Polythene, yog cov lus hauv tsev neeg paub.
Ib sab saum toj, PVA khoom yog dab tsi?
PVA yog ib lub npe luv rau polyvinyl cawv, dej-soluble khoom . Nws yog feem ntau siv nrog ntau-extruder FDM 3D tshuab luam ntawv ua kev txhawb nqa khoom . Qhov zoo tshaj plaws ntawm PVA filament yog nws muaj peev xwm yaj hauv dej. Qhov no txhais tau tias tsis muaj cov cim dab tuag nyob rau ntawm qhov luam tawm tom qab kev txhawb nqa khoom raug tshem tawm.
Dab tsi yog polyvinyl cawv siv rau hauv lub neej txhua hnub?
PVA yog siv nyob rau hauv sizing tus neeg sawv cev uas muab ntau zog rau textile yarns thiab ua ntawv ntau resistant rau roj thiab roj. Nws kuj yog siv los ua ib feem ntawm cov nplaum thiab emulsifiers, ua cov yeeb yaj kiab tiv thaiv dej, thiab ua cov khoom pib rau kev npaj ntawm lwm cov resins.
Pom zoo:
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