Thickeners tuaj nyob rau hauv ntau yam, thiab lawv txoj kev npaj sib txawv nyob ntawm seb hom. Feem ntau, qis-molecular- hnyav thickeners yog qhov yooj yim los npaj; Piv txwv li, qis-molecular- hnyav inorganic thickeners yog ua ke nrog surfactants rau thickening; ether / amine oxide thickeners yog npaj los ntawm oxidation cov tshuaj tiv thaiv; thiab ester thickeners tuaj yeem tau los ntawm kev ncaj qha esterification. High-molecular- hnyav thickeners tuav lub lag luam loj dua. Dhau li ntawm inorganic thiab ntuj siab -molecular{10}} hnyav thickeners, feem ntau yog npaj los ntawm emulsion polymerization thiab thim rov qab emulsion polymerization, nrog ob peb siv tshuaj polymerization, bulk polymerization, thiab nag lossis daus polymerization.
Kev daws Polymerization
Kev daws polymerization yog hais txog cov txheej txheem polymerization ntawm cov monomers yaj hauv cov kuab tshuaj thiab cov neeg pib, thiab lwm yam. Nws cov khoom feem ntau yog cov polymeric monomers, roj- soluble / dej- soluble pib, hnyav / dej.
Kev tshawb fawb txog kev daws teeb meem polymerization tau tsom mus rau kev npaj ntawm polyacrylic acid thickeners. Nws cov yam ntxwv yog tias ntau cov kuab tshuaj yuav tsum tau yaj cov polymer thaum lub sijhawm npaj. Feem ntau ntawm cov kuab tshuaj no yog insoluble hauv dej, thiab kev rov ua dua tom ntej yog tsim nyog. Yog li ntawd, tus nqi yog siab, thiab nws kuj yog kev puas tsuaj rau ib puag ncig tiv thaiv. Polymerization ntau
Bulk polymerization yog txheej txheem ntawm monomer tus kheej-polymerization pib lossis nrawm los ntawm qhov chaw tshav kub (lub teeb, tshav kub, hluav taws xob hluav taws xob, thiab lwm yam) nrog me me lossis tsis muaj tus pib / catalyst. Txoj kev no muaj cov kev xav tau tsawg rau monomers, tsis tas yuav muaj cov kuab tshuaj yaj, thiab cov khoom lag luam uas muaj ob peb impurities thiab siab purity. Nyob rau hauv xyoo tas los no, qee cov kws tshawb fawb tau pib siv cov polymerization ntau (ib ob -txoj kev) los npaj cov polyurethane thickeners, thawj cov khoom siv polymerizing polyurethane prepolymer thiab thaum kawg kawg -capping nws nrog ntev - chain fatty cawv kom tau cov khoom.
Emulsion Polymerization
Emulsion polymerization yog hais txog cov txheej txheem uas cov monomers sib txawv nyob rau hauv cov dej nyob rau hauv cov neeg kho tshuab nplawm nrog kev pab los ntawm ib tug emulsifier los tsim ib tug emulsion, thiab tom qab ntawd ib tug pib ntxiv rau pib monomer polymerization.
Emulsion polymerization tuaj yeem ua kom haum cov tshuaj tiv thaiv ntau dua, ua rau cov khoom siv polymers nrog cov khoom hnyav dua molecular, yooj yim los tswj hauv kev tsim khoom, thiab tso cai rau kom yooj yim tshem tawm cov seem monomers. Raws li cov txiaj ntsig zoo no, kev tshawb fawb thiab kev txhim kho ntawm txoj kev npaj no tau nrawm heev. Acrylic thickeners muaj cov thickening zoo heev thiab tshem tawm cov khoom, thiab tau sib xws nrog yuav luag tag nrho cov nonionic, anionic, amphoteric surfactants, thiab ntau cationic polymers, yog li nyiam cov neeg tshawb nrhiav.
Rov qab Emulsion Polymerization
Rov qab emulsion polymerization yog hais txog polymerization nyob rau hauv uas ib tug dej -insoluble organic hnyav thiab ib tug dej - soluble monomer ua ib tug dej - nyob rau hauv - roj emulsion nyob rau hauv dej nyob rau hauv qhov kev txiav txim ntawm ib tug emulsifier.
Txoj kev no yog ceev, me me, thiab yields siab molecular hnyav thiab kuj cov khoom ntshiab. Ob qho tib si nws cov nyhuv thickening thiab electrolyte tsis kam yog superior rau cov emulsion polymerization.
Cov hom thickeners npaj los ntawm thim rov qab emulsion polymerization zoo ib yam li cov uas npaj los ntawm emulsion polymerization, feem ntau polyacrylic acid thickeners. Piv nrog rau emulsion polymerization, thim rov qab emulsion polymerization yog qhov tsim nyog rau kev npaj electrolyte- tiv taus thickeners. Cov thev naus laus zis tshiab tuaj yeem ua tswvcuab raws li rov qab emulsion polymerization, xws li hluav taws xob polymerization los npaj cov ntawv tuab, tso cai rau kev tswj cov khoom siv hluav taws xob ntawm tus nqi polymerization thiab tsis txhob muaj kev cuam tshuam sai heev.
Dej nag Polymerization
Kev tshawb fawb txog kev npaj cov thickeners los ntawm nag lossis daus polymerization yog qhov txwv. Nws feem ntau suav nrog kev ntxiv cov dej nag rau qhov sib xyaw ntawm cov kuab tshuaj organic (benzene, toluene, lossis alkanes, thiab lwm yam) thiab acrylic acid monomers los npaj cov precursor precipitate, uas tom qab ntawd qhuav los yog calcined.
Piv nrog rau thim rov qab emulsion polymerization, nag lossis daus polymerization tsim cov khoom uas tsis zoo thickening zog thiab rhiab heev rau electrolytes. Qhia qee cov comonomers (xws li octadecyl methacrylate) rau hauv cov polymer tuaj yeem txhim kho nws cov electrolyte tsis kam.
