Kev tshawb fawb thiab kev loj hlob ntawm dimethyldiethoxysilane

Cov tshuaj silicone resin feem ntau yog siv los ua cov txheej txheem polymer ntawm cov txheej txheem kub-resistant, huab cua resistant txheej thiab cov khoom siv hluav taws xob kub kub.

1.2 technical evolution ntawm silicone resin

Ntawm txhua yam ntawm silicone polymers, silicone resin yog ib yam ntawm silicone khoom synthesized thiab siv thaum ntxov.Piv nrog rau kev txhim kho kev kub ceev ntawm silicone roj hmab qauv kev kho dua tshiab thev naus laus zis, kev txhim kho thev naus laus zis ntawm silicone resin kuj qeeb, thiab cov thev naus laus zis loj yog ob peb.Txij li thaum kwv yees li 20 xyoo dhau los, vim muaj kev vam meej ntawm cov tshuaj tsw qab heterocyclic tshav kub-resistant polymers, ib txhia ntawm lawv tau Ameslikas siv nyob rau hauv daim teb ntawm silicone resin.Txawm li cas los xij, qhov hnyav toxicity thiab hnyav curing tej yam kev mob ntawm aromatic heterocyclic tshav kub-resistant polymers txwv lawv daim ntawv thov.Nyob rau hauv xyoo tas los no, tib neeg tau pib nyiam ntau dua rau kev tshawb fawb thiab kev loj hlob ntawm silicone resin.Silicone resin muaj ntau qhov kub thiab txias thiab tiv thaiv kev laus.Kev ua tau zoo thiab kev ua haujlwm ntawm hydrophobic noo-pov thawj yog qhov zoo thiab lwm yam zoo, muaj cov cim qhia tias silicone resin yuav muaj qhov chaw loj dua rau yav tom ntej.

2. General silicone resin

2.1 txheej txheem ntawm cov khoom siv silicone

Ntau hom silicones muaj cov khoom sib txawv thiab cov txheej txheem hluavtaws.Nyob rau hauv daim ntawv no, cov txheej txheem ntau lawm ntawm ntau hom silicone resins tsuas yog qhia.

2.1.1 methyl silicone

2.2.1.1 synthesis ntawm methylsilicone resin los ntawm methylchlorosilane

Methylsilicones yog synthesized nrog methylchlorosilane ua cov khoom siv tseem ceeb.Vim yog cov qauv sib txawv thiab muaj pes tsawg leeg ntawm silicones (qhov crosslinking degree ntawm silicones, piv txwv li, [CH3] / [Si] tus nqi), qhov sib txawv synthesis yog xav tau.

Thaum qis R / Si ([CH3] / [Si] ≈ 1.0) methyl silicone resin yog synthesized, hydrolysis thiab condensation cov tshuaj tiv thaiv ceev ntawm lub ntsiab raw khoom monomers methyltrichlorosilane yog ceev heev, thiab cov tshuaj tiv thaiv kub yuav tsum nruj me ntsis tswj nyob rau hauv 0 ℃. , thiab cov tshuaj tiv thaiv yuav tsum tau nqa tawm nyob rau hauv ib tug compound solvent, thiab lub sij hawm cia ntawm cov tshuaj tiv thaiv cov khoom nyob rau hauv chav tsev kub tsuas yog ob peb hnub.Cov khoom zoo li no tsis tshua muaj nqi.

Nyob rau hauv lub synthesis ntawm R / Si methylsilicone resin, methyltrichlorosilane thiab dimethyldichlorosilane yog siv.Txawm hais tias hydrolytic condensation cov tshuaj tiv thaiv ntawm kev sib xyaw ntawm methyltrichlorosilane thiab dimethyldichlorosilane yog qeeb qeeb dua li ntawm methyltrichlorosilane ib leeg, hydrolytic condensation cov tshuaj tiv thaiv ceev ntawm methyltrichlorosilane thiab dimethyldichlorosilane yog qhov sib txawv heev, uas feem ntau tshwm sim los ntawm hydrolytic condensation ntawm methyltrichlorosilane advancement.Cov hydrolyzate tsis ua raws li qhov sib piv ntawm ob lub monomers, thiab methyl chlorosilane feem ntau hydrolyzed los tsim ib lub zos crosslinking gel, uas ua rau cov khoom tsis zoo ntawm methyl silicone resin tau los ntawm hydrolysis ntawm peb monomer.

2.2.1.2 synthesis ntawm methylsilicone los ntawm methylalkoxysilane

Cov tshuaj tiv thaiv tus nqi ntawm hydrolysis condensation ntawm methylalkoxysilane tuaj yeem tswj tau los ntawm kev hloov cov tshuaj tiv thaiv.Pib los ntawm methylalkoxysilane, methylsilicone resin nrog sib txawv crosslinking degrees tuaj yeem ua ke.

Kev lag luam methylsilicones nrog rau theem nrab ntawm crosslinking ([CH3] / [Si] ≈ 1.2-1.5) feem ntau yog npaj los ntawm hydrolysis thiab condensation ntawm methylalkoxysilane.Cov monomers ntawm methyltriethoxysilane thiab dimethyldiethoxysilane refined los ntawm deacidification yog tov nrog dej, ntxiv nrog ib tug kab ntawm hydrochloric acid los yog tsim nyog tus nqi ntawm muaj zog acid cation txauv resin (cov nyhuv catalysis ntawm macroporous muaj zog acid ion pauv resin yog zoo dua), thiab nyob.Kev sib deev av nplaum (qhuav tom qab acidification) yog siv los ua catalyst, rhuab thiab hydrolyzed.Thaum kawg taw tes, ntxiv tus nqi ntawm hexamethyldisilazane kom tshem tawm cov catalyst hydrochloric acid, los yog lim cov ion txauv resin los yog cov av nplaum uas siv los ua catalyst los txiav tawm cov tshuaj tiv thaiv condensation.Cov khoom tau txais yog cov kua dej cawv ntawm methylsilicone resin.

2.2.2 methyl phenyl silicone

Cov ntaub ntawv tseem ceeb rau kev tsim khoom ntawm methylphenyl silicone resin yog methyltrichlorosilane, dimethyldichlorosilane, Phenyltrichlorosilane thiab Diphenyldichlorosilane.Qee lossis tag nrho cov monomers saum toj no ntxiv nrog cov kuab tshuaj toluene lossis xylene, sib xyaw kom zoo, poob rau hauv dej hauv qab agitation, kub tswj cov tshuaj tiv thaiv hydrolysis, thiab HCl (hydrochloric acid aqueous tov), ​​cov khoom ntawm cov tshuaj tiv thaiv, raug tshem tawm. los ntawm kev ntxuav dej.Cov tshuaj hydrolyzed silicone yog tau, thiab tom qab ntawd ib feem ntawm cov kuab tshuaj yog evaporated los tsim cov concentrated silicone cawv, thiab tom qab ntawd cov silicone resin yog npaj los ntawm txias condensation los yog kub condensation cov tshuaj tiv thaiv, thiab cov silicone resin tiav yog tau los ntawm kev pom thiab ntim.

2.2.3 lub hom phiaj dav dav methyl phenyl vinyl silicone resin thiab nws cov khoom muaj feem xyuam

Cov txheej txheem tsim khoom ntawm methyl phenyl vinyl silicone resin zoo ib yam li methyl phenyl silicone resin, tshwj tsis yog tias ntxiv rau methyl chlorosilane thiab phenyl chlorosilane monomers, ib qho nyiaj ntawm methyl vinyl dichlorosilane thiab lwm cov yas uas muaj silicone monomers ntxiv rau hauv hydrolysis raw. cov ntaub ntawv.Cov monomers sib xyaw tau hydrolyzed, ntxuav thiab concentrated kom tau cov concentrated hydrolyzed silanol, ntxiv cov hlau organic acid ntsev catalyst, decompressing cua sov rau predefined viscosity, los yog tswj cov condensation cov tshuaj tiv thaiv qhov kawg taw tes raws li lub sij hawm gelation, thiab npaj methyl phenyl vinyl silicone resin.

Methylphenyl hydropolysiloxane, uas yog siv los ua cov khoom ntawm crosslinker ntxiv cov tshuaj tiv thaiv ntawm methylphenyl vinyl silicone resin, feem ntau yog ib lub nplhaib lossis linear polymer nrog me me ntawm polymerization.Lawv yog tsim los ntawm hydrolysis thiab cyclization ntawm methylhydrodichlorosilane, los yog los ntawm CO hydrolysis thiab condensation ntawm methylhydrodichlorosilane, Phenyltrichlorosilane thiab trimethylchlorosilane.

2.2.4 hloov silicone

Kev tsim khoom ntawm kev sib xyaw hloov pauv silicone resin nrog cov organic resin feem ntau yog nyob rau hauv toluene lossis xylene tov ntawm methylphenyl silicone resin, ntxiv alkyd resin, phenolic resin, acrylic resin thiab lwm yam organic resins, tag nrho sib tov sib npaug kom tau cov khoom tiav.

Lub copolymerized hloov kho silicone cob yog npaj los ntawm cov tshuaj lom neeg ntau.Cov organic resins uas tuaj yeem copolymerized nrog silicone muaj xws li polyester, epoxy, phenolic, melamine formaldehyde, polyacrylate, thiab lwm yam. Muaj ntau txoj kev siv hluavtaws tuaj yeem siv los npaj copolymerized silicone resin, tab sis txoj kev tsim khoom siv ntau dua yog copolymerization ntawm silicone cawv thiab organic cob.Ntawd yog, hydrolysis ntawm methyl chlorosilane thiab phenyl chlorosilane monomers ua ke kom tau hydrolyzed silicon cawv tov los yog cov tshuaj concentrated, thiab tom qab ntawd ntxiv cov organic resin prepolymer ua ntej rau cov catalyst, ces sib tov co cua sov evaporation hnyav, ntxiv zinc, zinc naphthenate thiab lwm yam catalysts, thiab cov tshuaj tiv thaiv cocondensation ntawm 150-170 degree qhov kub thiab txias, kom txog rau thaum cov khoom siv tshuaj tiv thaiv mus txog qhov zoo viscosity lossis predetermined gelation lub sij hawm, txias, Ntxiv hnyav rau yaj thiab lim kom tau cov khoom tiav ntawm copolymerized silicone resin.