Nyhuv ntawm epoxy kua roj ntawm dej tsis kam ntawm cov dej los ntawm polyurethane nplaum zaj duab xis
Nyob rau hauv tus txheej txheem ntawm kev npaj anionic waterborne polyurethane, vim hais tias cov kev qhia hydrophilic pawg kom cov dej tsis kam ntawm polyurethane zaj duab xis tsawg, los ntawm cov epoxy kua txiv roj hauv qhov cross-linking ntawm polyurethane molecular saw ua ib feem ntawm cov ntoo sib txuas, thiab kev taw qhia txog cov saw hlau ntev hydrophobic saw, ua kom nws cov dej tsis haum, hnyav ua haujlwm. Txhua epoxy soybean roj molecule muaj ~ 4 epoxy pawg, uas muaj peev xwm tsim tau ib co kev sib txuas nrog reticular nrog-nco fab, thiab txhim kho txoj kev kawm tag nrho. Thaum cov ntsiab lus ntawm epoxy soybean roj ntau zog, qhov kev sib tshuam crosslinking ntawm polyurethane tsim ntau zog, thiab cov khoom siv dag zog thiab dej tsis kam ntawm cov dej los ntawm polyurethane. Txawm li cas los, qhov qhia txog kev sib tshuam ntawm kev sib txuas lus yuav ua rau lub viscosity thaum ntxov ntawm lub cev kom ceev dhau heev, nws tus kheej rau qhov tshwm sim ntawm cov phenomenon.
Daim duab 3 yog thaum cov ntsiab lus ntawm Dmpa yog 5%, qhov dej nqus dej ntawm cov dej hauv cov dej polyurethane txawv nrog cov ntsiab lus ntawm epoxy kua roj. Nws pom tau tias cov dej ntawm qhov dej ntawm polyurethane cov yeeb yaj kiab tau zoo heev nrog rau qhov nce ntawm epoxy kua roj cov ntsiab lus. Qhov no yog vim tias qhov nce ntawm cov roj carbon dioxide tau epoxy, qhov degree ntawm crosslinking ntawm polyurethane molecular saw nce, ntau dua qhov dej ntawm lub cev, qhov nyuaj nyuaj rau dej lub cev kom nkag mus rau hauv cov yas yeeb yaj kiab, yog li cov dej nqus dej kom tsawg, qhov tsis kam ntawm zaj duab xis yog ho txhim kho. Tab sis cov roj ntawm epoxy soybean roj loj heev, yuav ua rau cov prepolymer viscosity nce, lub lag luam yog phim, lub emulsification nyuaj, tsis tau txais lub emulsion stability nrog finer particle loj. Thaum cov roj carbon dioxide tau roj ntau dua li 8%, nws yooj yim heev rau hauv cov txheej txheem ntawm Prepolymer. Yog li no, cov roj phom epoxy kua roj tsawg yuav tsum tsis txhob loj, mus rau 4% ~ 6% thiab.
Cov nyhuv ntawm 2.4 Epoxy kua roj rau cov nplaum ntawm cov khoom siv los ntawm cov khoom siv polyurethane
Epoxy soybean roj muaj cross-linking cov nyhuv ntawm polyurethane, epoxy kua tshuaj molecule muaj 3 ~ 4, epoxy puag tau hnov mob isocyanate, txhim kho cov degree ntawm crosslinking polyurethane molecule, thiab ua kom lub cohesion ntawm cov dej polyurethane.
Table 2 Cov nyhuv ntawm qhov tshuaj ntawm cov tshuaj roj epoxy soybean nyob rau hauv cov nplaum ntawm cov khoom siv los ntawm polyurethane adhesives.
Raws li tuaj yeem pom los ntawm cov rooj zaum 2, T-tis lub zog nce nrog nce ntawm cov roj epoxy soybean roj, thiab ho txo. Qhov no vim hais tias epoxy kua ntsev roj txhim kho cov ntaub ntawv crosslinking ntawm polyurethane molecular saw, lub cohesion ntawm lub nplaum yog ntau zog, thiab lub adhesion lub zog ntawm cov adhesives yog ntau zog, tab sis nrog cov nyiaj ntawm cov roj epoxy soybean, Prepolymer emulsification nyuaj thiab kev ruaj ntseg ntawm emulsion decreases, uas ua rau cov thawj ntawm lub zog ntawm nplaum polyurethane nplaum. Rau lwm cov tes, vim muaj qhov sib ntxiv ntawm epoxy kua roj, cov viscosity ntawm cov dej tsis muaj polyurethane nplaum yog tsawg, uas yog siv rau cov qe ntawm cov substrate thiab lub zog ntawm cov kua dej polyurethane adhesives. Tuaj kom tiav, thaum cov roj epoxy soybean cov ntsiab lus yog 4% ~ 6%, qhov ua tau lub zog ntawm polyurethane ua tau zoo dua.
T-tev tawv lub zog yog ib qho kev ntsuas ntawm lub zog ntawm kev sib txuas ntawm cov khaubncaws sab nraud povtseg ntawm cov yeeb yaj kiab. Yuav kom ntseeg tau tias cov yeeb yaj kiab zaj nkauj tsis yog stratified, lub zog ntawm kev sib tshuam ntawm interlayer yuav tsum tsis pub tsawg tshaj 100n / m. Nws tuaj yeem pom los ntawm lub rooj 2 tias thaum noj tshuaj rau epoxy soybean roj yog 4% ~ 6%, taum lub zog ntawm cov dej los ntawm polyurethane rau cov yeeb yaj duab sib txawv ntau tshaj 100n / m, uas qhia tau hais tias lub nplaum yuav siv tau rau tsevneeg ntau zaj duab xis zaj duab xis.