Carboxylic hydrophilic chain extenders DMBA thiab DMPA.

Ua ntej

Hauv kev tsim cov dej polyurethane, carboxylic acid li anionic hydrophilic saw extender yog ib hom carboxylic acid nrog diol, uas tau siv dav rau nws cov qauv molecular thiab cov khoom zoo heev.
Carboxylic acid hom chain extender mas suav nrog 2,2-dihydroxymethylpropionic acid (DMPA) thiab 2,2-dihydroxymethylbutyric acid (DMBA).Nws yog ib qho tshwj xeeb multifunctional blocked diol molecule nrog ob pawg hydroxyl thiab carboxyl.Tom qab neutralization nrog alkali, cov dawb acid pab pawg tuaj yeem txhim kho cov dej solubility lossis dispersion kev ua tau zoo ntawm cov resin;Polar pawg tau qhia los txhim kho cov adhesion ntawm coatings thiab dyeing zog ntawm hluavtaws fibers;Ua kom cov alkali solubility ntawm txheej.Nws tuaj yeem siv rau dej-soluble polyurethane system, dej-soluble alkyd resin thiab polyester cob, epoxy ester txheej, polyurethane elastomer thiab hmoov txheej.
Nws kuj tseem tuaj yeem siv rau hauv cov ntaub ntawv tawv nqaij, kua siv lead ua kua, inks, khoom noj khoom haus thiab cov tshuaj nplaum, tshwj xeeb tshaj yog nyob rau hauv kev tsim cov dej emulsion polyurethane thiab tawv tiav cov neeg ua haujlwm.Nws tsis yog tsuas yog cov saw txuas ntxiv, tab sis kuj yog tus neeg sawv cev zoo emulsifying rau polyurethane, uas tuaj yeem txhim kho kev ruaj ntseg ntawm polyurethane dej lotion, yog li nws yog dav siv.

Qhov zoo ntawm Kev Siv Dihydroxymethyl Carboxylic Acid

Aqueous polyurethane lotion feem ntau qhia hydrophilic tus neeg sawv cev rau hauv polyurethane molecular saw, ces neutralizes nrog alkali los ua ntsev, thiab disperses nyob rau hauv dej deionized los ntawm mechanical stirring los tsim polyurethane aqueous lotion.
Feem ntau muaj peb hom hydrophilic agents siv nyob rau hauv waterborne polyurethane: anionic, cationic thiab non-ionic.Hom anionic feem ntau suav nrog: 2,2-dihydroxymethylpropionic acid, 2,2-dihydroxymethylbutyric acid, tartaric acid, butanediol sulfonate, sodium ethylenediamineethanesulfonate, glycerol thiab maleic anhydride;Cationic hom feem ntau suav nrog: methyldiethanolamine, triethanolamine, thiab lwm yam;Hom tsis ionic feem ntau suav nrog hydroxyl terminated polyethylene oxide.
Cov ntsiab lus ntawm non-ionic hydrophilic tus neeg sawv cev xws li polyethylene oxide yuav tsum siab heev kom cov dispersion ruaj khov.Cov dej hauv dej polyurethane resin ua los ntawm hydroxyl polyoxyethylene ether li hydrophilic pawg muaj cov electrolyte tsis kam, tab sis cov dej tsis kam ntawm cov yeeb yaj kiab yog qhov tsis zoo, yog li nws tsis ua haujlwm;
Cationic hydrophilic tus neeg sawv cev, xws li ethylenediamine sodium acrylate adduct, raws li hydrophilic compound, ua rau tag nrho cov tshuaj tiv thaiv kab mob alkaline.Tsis tsuas yog muaj kev cuam tshuam sai ntawm - NH2 pawg thiab - NCO pawg, tab sis kuj muaj kev cuam tshuam ntawm - NCO pawg thiab - nhcoo.Yog li ntawd, cov tshuaj tiv thaiv yog qhov nyuaj los tswj thiab yooj yim rau gel.Tsis tas li ntawd, cov tshuaj pleev thaiv hnub tau npaj muaj cov khoom ntxhib thiab cov yeeb yaj kiab tsis zoo-tsim dej, yog li nws tsis tuaj yeem siv hauv kev lag luam;
Dihydroxymethyl carboxylic acid nyob rau hauv daim ntawv anionic muaj ob pawg hydroxyl thiab kuj ua raws li cov saw txuas ntxiv.Qhov ob lub luag haujlwm no ua rau nws pom qhov zoo hauv kev npaj ntawm tus kheej emulsifying Pu lotion.Thaum lub sij hawm synthesis ntawm carbamate, nws ua rau cov tshuaj tiv thaiv kab mob acidic.Nyob rau hauv acidic tej yam kev mob, cov tshuaj tiv thaiv ntawm - NCO thiab - Oh yog me ntsis, thaum - nhcoo - tsis koom nyob rau hauv cov tshuaj tiv thaiv thiab yuav tsis ua gel.Tsis tas li ntawd, dimethylol carboxylic acid kuj ua raws li cov saw txuas ntxiv, kom cov pab pawg hydrophilic (piv txwv li, carboxyl pawg) nyob rau hauv macromolecular saw ntu.Siv tertiary amine ua tus neeg sawv cev nruab nrab, cov dej ua kua polyurethane nrog kev ruaj ntseg zoo thiab cov yeeb yaj kiab zoo heev thiab cov kuab tshuaj tiv thaiv tuaj yeem npaj tau.Dihydroxymethyl carboxylic acid yog qhov zoo tshaj plaws hydrophilic compound dav siv nyob rau hauv kev npaj ntawm waterborne polyurethane resin.

2,2-Dihydroxymethylpropionic Acid (DMPA) Thiab 2,2-Dihydroxymethylbutyric Acid (DMBA)

Ntawm ob hom Dihydroxymethyl carboxylic acids, 2,2-dihydroxymethyl propionic acid tau siv rau lub sijhawm ntev thiab yog hydrophilic chain extender dav siv tam sim no.Txawm hais tias nws muaj ntau yam zoo, nws kuj muaj ntau qhov tsis zoo, feem ntau yog vim nws qhov siab melting point (180-185 ℃), uas nyuaj rau cua sov thiab yaj, uas yuav tsum tau ntxiv cov organic solvents xws li N-methylpyrrolidone (NMP), n N-dimethylamide (DMF), acetone, thiab lwm yam, thaum NMP muaj qhov kub hnyiab, uas nyuaj rau tshem tawm tom qab npaj APU.Ntxiv mus, DMPA muaj me me solubility nyob rau hauv acetone, thiab ib tug loj npaum li cas ntawm acetone yuav tsum tau ntxiv nyob rau hauv lub synthesis txheej txheem.Cov txheej txheem tshem tawm ketone tsis yog tsuas yog pov tseg lub zog xwb tab sis kuj ua rau muaj kev nyab xeeb.Yog li ntawd, kev siv 2,2-dihydroxymethylpropionic acid tsis yog tsuas yog siab zog noj, tab sis kuj yooj yim ua rau cov organic residues hauv cov khoom.
Piv nrog 2,2-dihydroxymethyl propionic acid, 2,2-dihydroxymethyl butyric acid muaj qhov zoo hauv qab no:
1. Nws muaj cov solubility zoo dua hauv cov kuab tshuaj organic.Cov lus hauv qab no qhia txog cov ntaub ntawv solubility ntawm DMBA thiab DMPA hauv qhov sib txawv ntawm qhov kub thiab txias;
Solubility cov ntaub ntawv ntawm DMBA thiab DMPA nyob rau hauv txawv kub thiab hnyav:

Solubility: unit: g / 100g hnyav
Solubility hauv dej: 48% rau DMBA thiab 12% rau DMPA.

2. Cov tshuaj tiv thaiv siab, cov tshuaj tiv thaiv ceev ceev thiab cov tshuaj tiv thaiv qis.Piv txwv li, lub sij hawm cov tshuaj tiv thaiv rau synthesizing polyurethane prepolymer yog luv, feem ntau tsuas yog 50-60 feeb, thaum DMPA yuav siv sij hawm 150-180 feeb;
3. Nws yog siv rau waterborne polyurethane lotion nrog finer particle loj thiab nqaim faib;
4. Tsawg melting point, 108-114 ℃;
5. Kev sib txawv ntawm cov qauv tuaj yeem txo qhov kev siv cov kuab tshuaj, yog li txo tus nqi ntawm cov kuab tshuaj thiab cov dej khib nyiab pov tseg;
6. Nws tuaj yeem siv los npaj cov kuab tshuaj tsis muaj cov tshuaj polyurethane thiab polyester;
Hauv cov txheej txheem synthesis tiag tiag, nws tsis tas yuav haus cov kuab tshuaj.Cov tshuaj pleev ua kom muaj kev ua tau zoo thiab cov khoom siv zoo heev ntawm cov yeeb yaj kiab, uas tsis tsuas yog txo lub sijhawm cov tshuaj tiv thaiv, txo lub zog noj, tab sis kuj txuag lub zog.Yog li ntawd, 2,2-dihydroxymethyl butyric acid yog cov paub zoo tshaj plaws hydrophilic compound.