Txhawm rau pab txhawb txhua tus neeg txoj kev kawm thiab kev nkag siab, Kuv yuav piav qhia luv luv txog qee qhov tseem ceeb ntawm kev suav cov qauv thiab cov ntsiab lus yooj yim uas cov tib neeg koom nrog polyurethane thev naus laus zis yuav tsum nkag siab thiab nkag siab.
1. Cov pab pawg Hydroxyl
Hydroxyl sib npaug: Qhov hnyav ntawm resin sib npaug rau ib pawg hydroxyl, xam raws li:
E(OH)= Nyhav ntawm Resin/Number of Hydroxyl Groups hauv Resin Molecule
Cov ntsiab lus Hydroxyl: Qhov hnyav feem pua ntawm cov pab pawg hydroxyl hauv txhua 100 grams ntawm cov resin, xam raws li:
OH% =(N * 17 / Qhov hnyav ntawm Resin) * 100%
qhov twg N yog tus naj npawb ntawm pawg hydroxyl.
Hydroxyl Tus Nqi: Tus naj npawb ntawm milligrams ntawm poov tshuaj hydroxide sib npaug rau cov ntsiab lus hydroxyl ib gram ntawm cov qauv, xam raws li:
Hydroxyl Cov ntsiab lus =1700 / Hydroxyl sib npaug
Tus nqi Hydroxyl=56100 / Hydroxyl Cov ntsiab lus= Hydroxyl sib npaug * 33
2. Isocyanate Index
TDI Index: Qhov piv ntawm qhov tseeb ntawm TDI siv rau qhov theoretical npaum li cas ntawm TDI, xam raws li:
TDI Index=TDI Tus nqi tiag tiag siv / Theoretical TDI Tus Nqi
Sib npaug: xam raws li:
Sib npaug =Molecular Luj / Functionality
For TDI:
TDI Equivalent=4200 / NCO%
TDI Nyiaj: xam raws li:
TDI Tus Nqi =(TDI Index / 100) * TDI Equivalent* (100 / Polyol Equivalent + Cov ntsiab lus dej / Dej sib npaug)
qhov twg Polyol sib npaug =56100 / Hydroxyl Tus nqi, Dej sib npaug =9.
Rau MDI, cov qauv yog tib yam, hloov TDI nrog MDI.
NCO Cov ntsiab lus: Cov ntsiab lus ntawm isocyanate pawg (NCO), feem ntau qhia raws li feem pua.
3. Cov tshuaj tiv thaiv
Tus nqi tshuaj tiv thaiv yog hais txog tus nqi uas qhov concentration ntawm cov tshuaj nyob rau hauv cov tshuaj tiv thaiv kab mob hloov lub sij hawm, qhia qhov ceev ntawm cov tshuaj tiv thaiv. Thaum lub sij hawm cov tshuaj tiv thaiv, thaum lwm yam kev mob (xws li kub thiab ntim) yog tsau, lub concentration ntawm cov tshuaj nyob rau hauv cov tshuaj tiv thaiv system hloov lub sij hawm: lub concentration ntawm reactants maj mam txo, thaum lub concentration ntawm cov khoom maj mam nce. Txawm li cas los xij, cov tshuaj tiv thaiv hloov pauv raws sijhawm. Cov tshuaj tiv thaiv tus nqi ntawm ib lub sijhawm tshwj xeeb yog hu ua cov tshuaj tiv thaiv tam sim, feem ntau qhia hauv moles / (dm³·s). Qhov nruab nrab cov tshuaj tiv thaiv feem ntau yog hu ua cov tshuaj tiv thaiv kab mob. Cov yam ntxwv cuam tshuam rau cov tshuaj tiv thaiv muaj xws li siab, kub, catalyst, concentration, hnyav, thiab lwm yam.
4. Lub zog tensile
Lub zog tensile yog hais txog kev ntxhov siab ntawm cov khoom uas muaj qhov siab tshaj plaws ntawm cov yas deformation. Hauv kev sim tensile, qhov siab tshaj plaws tensile kev nyuaj siab ib tus qauv tiv taus kom txog thaum nws tawg yog lub zog tensile, qhia hauv MPa. Nws tseem hu ua tensile zog los yog tensile kuj.
Thaum kuaj lub zog tensile nrog cov cuab yeej, cov ntaub ntawv xws li tensile fracture stress, tensile yield stress, thiab elongation ntawm so kuj tuaj yeem tau.
Tensile Strength: xam raws li:
Tensile Strength =Maximum Load / (Sample Width * Sample Thickness)
Elongation ntawm Break: xam raws li:
Elongation ntawm Break =(Length ntawm Break-Initial Length) / Initial Length * 100%
Peel Strength: Qhov siab tshaj plaws kev puas tsuaj rau ib cheeb tsam kev sib koom ua ke, sawv cev rau lub zog yuav tsum tau tev cov khoom sib txuas ntawm ib chav tsev dav ntawm cov qauv. Nws tau nthuav tawm hauv N / cm, N / m, lossis kN / m.