Lub viscosity ntawm cov kua silicone roj hmab tau cuam tshuam los ntawm ntau yam ntawm ntau yam, uas tswj hwm nws cov qauv molecular, kev sib cuam tshuam, lossis lub cev. Cov hauv qab no yog cov ncauj lus kom ntxaws kev tshuaj xyuas ntawm lub ntsiab tseem ceeb:
1. Molecular hnyav thiab cov qauv ntawm lub hauv paus polymer (roj hmab puag)
Molecular Qhov hnyav: qhov hnyav dua ntawm cov roj hmab hauv cov roj hmab ua kom ntev dua molecular thiab ntau tshaj entanglements ntawm cov seg segments, nce viscosity, Piv txwv li, lub viscosity ntawm 107 roj hmab puag-paus liab los ntawm 10,000 cp rau 50,000 CP, nrog hnyav molecular hnyav qhia tau ntau dua cov neeg viscosity siab dua.
Cov qauv molecular: ncaj- saw silicone rub tau qis viscosity muaj qis {{1}! Piv txwv li, lub viscanity ntawm vinyl - muaj kev sib ntxiv los ntawm cricone r cuam tshuam vim yog lawv cov saw alolecular.
2. Cov tub lim thiab cov ntsiab lus
Hom tub lim:
Silica (fumed lossis precipitated): raws li kev txhawb nqa cov lim thiab tensile lub zog ntawm silicone roj hmab, tab sis tseem ceeb nce viscosity. Fumed silica has a larger surface area and a more pronounced viscosity-increasing effect. Calcium carbonate thiab Silica Hmoov: Raws li cov khoom siv inert, tab sis ntxiv ntxiv tuaj yeem ntxiv viscosity vim yog particle tsub zuj zuj.
Cov ntsiab lus sau ua ke: cov tub muab tubtoom cov chaw muab tub lim, cov viscosity ntau dua. Piv txwv li, ncoo luam ntawv silicone yuav tsum muaj kev nyuaj (ib ncig ntawm 50 degrees), thiab nrog ib tug raw viscosity yog qhov siab dua li ntawm cov silicone.
3. Txuas ntxiv ntawm cov planizers (mob)
Silicone roj: Dosethyl silicone roj yog ib qho kev siv plasterizer ntau uas txo cov viscosone silicone. Qhov sib ntxiv sib ntxiv yuav tsum tsis tshaj 10%. Kev ntxiv ntau dhau tuaj yeem ua rau nto tawm saum npoo av, tsis muaj zog, thiab tsis zoo ntawm cov khoom siv me ntsis tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho cov khoom tom qab kho.
Lwm yam raug mob, xws li tsawg - viscosity vincority roj, tuaj yeem siv los kho cov roj sicionpose, tuaj yeem siv los kho cov khoom sib txawv.
4. Crosslinkers thiab kho cov tshuab
Crosslinker Hom:
Hydrogenated Silicone roj (ntxiv - Hom Silicone): Qhov Ntau Dua Cov Crosslink Qwj thiab ntau dua lub hardness tom qab kho tau. Txawm li cas los xij, qhov tsis paub txog viscosity tej zaum yuav nce ntxiv vim muaj kev nyiam ntawm cov molecular chains kom hla.
Organotin catalyst (hws {- hom silicone): qhov kev sib txuas lus ntau zaus tuaj yeem ua rau muaj kev sib txawv, ua rau muaj kev txawv txav ntawm viscosity siab. Kev Kho Mob:
Qhov kub thiab txias: nce qhov kub tuaj yeem txo cov viscosity (viscosity txo los ntawm kwv yees li ib nrab ntawm ib nrab ntawm ib nrab), tab sis qhov kev kho kub nce siab yuav tsum tau tswj kom tsis txhob muaj kev zam ntau dhau.
Lub sijhawm: Lub sijhawm kho ntau dhau yuav ua rau txuas ntxiv mus ntxiv ntawm cov saw molecular, ua kom viscosity ntxiv.
5. Molecular saw kawg pawg thiab reflectivity
Cov pab pawg muaj cov roj av: silicones uas muaj cov roj hmab, hydroxyl, lossis hydroxen pawg ntawm cov molecular pawg kawg muaj sib txawv inter -}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}} Segment sib tham. Piv txwv li, silicones nrog cov ntsiab lus vinyl siab muaj qis viscosity tab sis siab dua hardness tom qab kho.
Capping cov neeg sawv cev: Siv cov neeg sawv cev sib txawv (xws li hexamethandisiloxane tuaj yeem kho cov kev ua si ntawm cov molecular saw xaus, yog li cuam tshuam viscosity.
6. Ua thiab sib xyaw
Stirring ceev thiab lub sijhawm: siab - Ceev stirring tuaj yeem qhia cov molecular charcity, ua rau muaj kev nce ib ntus hauv viscosity. Txhim kho kev sib xyaw ua kom muaj kev sib xyaw ua ke ntawm cov muab tub lim thiab zam kev tsis txaus siab ib cheeb tsam kev txawv txav.
Degassing: Undegassed Silicone yuav muaj cov viscosity zoo nkauj dua li tus nqi muaj zog vim muaj cov khoom siv tshuab hluav taws xob tsis muaj zog ntxiv tom qab kho cov khoom siv sab nraud
Qhov kub thiab txias: Kev nce qib huab cua kub txo qis (ua raws li cov sib npaug ntawm Arrhenius), tab sis cov nyhuv ntawm kev kho cov tshuaj tiv thaiv yuav tsum tau txiav txim siab.
Shear Force: Silicone kua yog qhov tsis -} Cov kua dej me me (shear- shak cov txheej txheem xws li kev txhaj tshuaj molding thiab txau.
Piv txwv ntawm viscosity tswj nyob rau hauv cov ntawv thov kev siv
Qhov tsis muaj viscosity yuav tsum muaj: piv txwv li, hauv kev tiv tauj txhaj tshuaj molding, ib qho ntxiv - hom silicone nrog viscosity hauv qab 10,000 CP yuav tsum muaj. Qhov no tau ua tiav los ntawm kev xaiv qhov hnyav molecular hnyav lub hauv paus thiab ib qho me me ntawm cov roj silicone.
Cov Viscososity High: Piv txwv li, hauv cov tshuab hluav taws xob siab, muaj viscosity siab yog qhov yuav tsum tau los tiv thaiv kev txaus. Qhov no tuaj yeem ua tiav los ntawm kev ntxiv cov feem ntau ntawm silica lossis siv lub hauv paus branched.
Viscosity - hardness sib npaug: Ncoo luam ntawv silicone yuav tsum muaj ob qho nyuaj (50 degrees) thiab nruab nrab viscosity. Qhov no yog tiav los ntawm kev ua kom zoo ntawm cov silica rau cov roj silicone.