Cov tshuaj tiv thaiv ntawm apolyurethane prepolymerthiab tus kws kho mob txiav txim siab tus cwj pwm ua, qhov ruaj khov, thiab qhov kawg ntawm cov khoom siv ntawm polyurethane elastomer. Txawm hais tias tsim cov khoom lag luam, lub log, cov ntxaij vab tshaus mining, lossis kev cai molded polyurethane Cheebtsam, tswj cov txheej txheem kho yog qhov tseem ceeb rau kev ua tiav cov khoom zoo ib yam.
Cov tshuaj tiv thaiv tsis tau tswj tau tuaj yeem ua rau gelation sai, kho tsis tiav, npuas, ntau qhov shrinkage, lossis lub cev tsis ruaj khov. Kev nkag siab txog cov ntsiab lus tseem ceeb uas cuam tshuam rau cov tshuaj tiv thaiv tso cai rau cov tuam txhab tsim kho kom zoo dua qub thaum txhim kho cov khoom lag luam.
Chemistry Tom qab Polyurethane Curing
Kev kho cov tshuaj tiv thaiv ntawm polyurethane elastomers yog raws li cov tshuaj tiv thaiv ntawm cov pab pawg isocyanate thiab cov nquag hydrogen compounds.
Thawj cov tshuaj tiv thaiv yog nruab nrab ntawm NCO pawg hauv polyurethane prepolymer thiab hydroxyl lossis amine pawg hauv cov tshuaj tua kab mob, tsim cov polyurethane lossis polyurea linkages. Cov tshuaj tiv thaiv tus nqi thiab qib ntawm kev hloov pauv ncaj qha cuam tshuam rau hardness, lub zog, elasticity, thiab qhov tseeb qhov tseeb.
Peb yam tseem ceeb txiav txim siab kho tus cwj pwm.
Thawj yog polyurethane prepolymer nws tus kheej, nrog rau NCO cov ntsiab lus, kub, viscosity, thiab dawb isocyanate qib.
Qhov thib ob yog tus neeg sawv cev kho, nrog rau nws hom tshuaj, qhov sib npaug sib npaug, thiab ntau npaum li cas.
Qhov thib peb yog kev siv cov catalysts, uas tuaj yeem ua kom cov tshuaj tiv thaiv kho kom zoo txawm tias muaj tsawg heev.
Tswj cov tshuaj tiv thaiv
Cov tshuaj tiv thaiv ruaj khov yog qhov tseem ceeb rau kev ua tiav zoo flowability, zoo pwm filling, thiab uniform curing.
Optimize NCO Index
NCO Performance index sawv cev rau qhov sib piv ntawm cov ntsiab lus isocyanate tiag tiag thiab qhov theoretical npaum li cas yuav tsum tau ua kom tiav cov tshuaj tiv thaiv.
Hauv ntau lub tshuab cam khwb cia polyurethane, qhov ntsuas me ntsis saum toj ntawm stoichiometric piv feem ntau xaiv los ua kom tiav kev kho. Txawm li cas los xij, NCO qhov Performance index siab heev tuaj yeem ua rau nce qib tom qab- kho cov tshuaj tiv thaiv, ua rau muaj kev poob qis dua, brittleness, thiab xim hloov. Ntawm qhov tod tes, NCO qhov Performance index tsis txaus yuav ua rau cov khoom tsis zoo, ua rau cov tawv nqaij mos, tsis muaj zog, lossis tackiness.
Xaiv cov qauv tsim nyog raws li cov txheej txheem polyurethane tshwj xeeb yog qhov tseem ceeb rau kev tswj xyuas cov khoom sib npaug.
Xaiv tus tsim nyog Curing Agent
Cov tshuaj tua kab sib txawv tsim cov tshuaj tiv thaiv sib txawv.
Aromatic amine curing agents xws li MOCA thiab DETDA feem ntau hnov mob sai dua li glycol -raws li cov tshuaj tua kab mob xws li BDO lossis ethylene glycol.
Fast-reacting systems yog haum rau siab -kev ua tau zoo industrial elastomers tab sis xav tau cov txheej txheem meej. Slower curing agents muab lub lauj kaub lub neej ntev dua thiab feem ntau nyiam rau cov castings loj lossis cov pwm nyuaj uas tsim nyog lub sijhawm ua haujlwm txaus.
Tus neeg sawv cev kho yuav tsum tau xaiv ib txwm raws li daim ntawv thov, txoj kev tsim khoom, thiab lub cev xav tau.
