Muaj ob txoj hauv kev tshawb nrhiav. Ib qho yog los tshawb nrhiav los ntawm qhov loj feem ntawm cov qauv. Piv txwv li, nyob rau hauv ib tug formula, thaum TDI nyob rau hauv 100 feem ntawm polyether yog ntxiv los yog rho los ntawm 1 kg, T-9 yog txo los yog ntxiv li ntawm 7 grams. Piv txwv li, ntau npaum li cas ntawm foaming silicone roj yog siv, thiab ib tug yooj yim empirical mis (kwv yees inversely proportional) ntawm qhov ntom thiab cov roj silicone tuaj yeem muab tau. Lwm qhov piv txwv yog qhov tsawg kawg nkaus ntawm TDI, uas yog ib qho qauv qhia txog kev muaj peev xwm ntawm polyether, dej thiab methane, thiab lwm yam. Lwm qhov yog "pinch lub taub hau mus rau tus Tsov tus tw", cov tshuaj tiv thaiv tsis tu ncua, kev hloov pauv nruab nrab tsis quav ntsej txog nws, tsuas yog thawj zaug cov tshuaj tiv thaiv concentration (daim ntawv qhia) thiab ob feem ntawm lub xeev thaum kawg ntawm cov tshuaj tiv thaiv muaj kev txhawj xeeb. Nws tuaj yeem hais tau tias feem ntau ntawm cov qauv yooj yim empirical uas tuaj yeem tiv taus qhov kev sim ntawm ntau lawm yog raws li lub hauv paus no, thiab daim ntawv thov hauv zos yog nws tus yam ntxwv. Nws yuav nthuav yog tias peb decompose cov txheej txheem tshuaj tiv thaiv mus rau kaum rau pua pua ntawm cov tshuaj tiv thaiv scenarios kom paub thiab suav. Yuav txhais li cas cov xwm txheej no tshwm sim? Peb yeej pom ib yam khoom: catalyst (catalyst). Phau ntawv qhia hais tias hom ntawm cov tshuaj tiv thaiv catalyst yog: cov tshuaj tiv thaiv catalyst ~ catalyst nag lossis daus ~ catalyst re-reaction, xws li lub voj voog tuaj yeem txhais tau tias yog cov tshuaj tiv thaiv hauv zos. Piv txwv li: tus nqi ntawm TDI hauv koj 100 feem pua polyether yog 60 kg, thiab tus nqi ntawm amine yog 0.2 kg, yog li muaj pes tsawg lub voj voog muaj rau qee yam tshuaj tiv thaiv hauv cov qauv no? Muaj pes tsawg qhov xwm txheej tshwm sim?
Wb xam:
60x1000/174=344.83
0.2x1000x2/340=1.1765
(344.83-1.1765)/1.1765=292.1
Muaj 292 lub voj voog nrog 292 qhov xwm txheej tshwm sim. Yog tias koj mus dhau qhov kev xam ib los ntawm ib qho, yuav tsis muaj teeb meem hauv ob peb teev. Qhov tseeb, tag nrho peb lub neej txheej txheem yog ib daim ntawv qhia hloov, thiab lub sij hawm ntawm hnub yog lub catalyst.
Raws li cov foaming ncav cuag ib lub hnub nyoog, xws li ntau tshaj 20 xyoo, nws pom tau hais tias cov nyhuv ntawm kev nkag siab txog cov lus teb raws li cov qib zoo yog yuav luag xoom. Txawm hais tias kuv muaj ntau tshaj li ib txhiab tus qauv tsim tawm hauv kuv txhais tes, kuv tseem nrhiav tsis tau txoj cai hauv peb lub tswv yim los ntawm cov lej hloov no, thiab nws tseem zoo li pos huab. Los ntawm qhov kev xav ntawm kev tsa tsev neeg, kuv tsis xav mus rau hauv cov kev hloov pauv no xws li kev tshawb fawb txog kev tshawb fawb, tab sis tsawg kawg peb yuav tsum xyuas kom meej tias muaj ntau qhov kev kwv yees thiab ntau qhov kev lees paub hauv kev tsim khoom ib txwm muaj, thiab tsis tshua muaj kev txhawj xeeb thiab kev taug kev. Txawm hais tias qhov no tsis yog qhov yuav tsum tau muaj siab, peb tsis tuaj yeem ua tau raws li qhov kev nkag siab ntawm cov khoom siv zoo. Qhov no qhia tau hais tias muaj lwm txoj hauv kev uas peb tsis paub txog (cia ib leeg tswv). Cov neeg sab nrauv xav tias cov npuas uas tau ua rau kaum lossis nees nkaum xyoo tsis yooj yim thiab ntuj. Qhov tseeb yog, feem ntau ntawm cov dej so tes, los yog muaj ib qho yooj yim me ntsis mis, thiab pib ua txhua hnub. Ob leeg koom nrog cov qauv nrog cov txheej txheem siab ntxiv tus nqi, xav tau ntau yam kev xav tau, nqaim qhov sib npaug, thiab cov zis tsis loj heev. Txawm hais tias qhov xwm txheej zoo li cas, thaum foaming, koj yuav tsum ua kom nquag plias. Foaming zoo ib yam li taug kev ntawm ib txoj hlua khi, taug kev hauv qhov tsis sib luag. Wow, txawm tias kuv tau ua npuas yuav luag 30 xyoo, ib zaug kuv muab kuv tus kheej ob peb lub hlis so thiab nres cov npuas, thaum kuv tsis tangled hauv kuv lub siab, kuv lub hlwb thiab lub siab feem ntau tsis zoo. Vim li cas thiaj zoo li no? Puas yog kev ntxhov siab ua haujlwm xwb? Kuv xav tias paub txog txoj kev thiab tsis muaj peev xwm ua tau zoo yog qhov tseem ceeb.
Nyob rau hauv kev pom ntawm no, peb tsis nco qab tsom peb lub siab ntawm lub me me ntawm cov teeb meem muaj pes tsawg leeg: pab pawg. Thaum peb paub txog isocyanates los ntawm qhov zoo, muaj TDI-80, TDI-65, crude MDI, hloov MDI, MDI-50, MDI-100, thiab lwm yam. Thaum peb tsom mus rau reactive cov pab pawg reactive, qhov sib txawv ntawm cov khoom siv raw saum toj no yog sib npaug rau qhov sib txawv ntawm cov haujlwm ntawm N=C=O pawg cuam tshuam los ntawm cov neeg hloov pauv thiab steric hindrance. Thaum peb saib cov tshuaj tiv thaiv me me, peb yuav pom tias polyether-type high-rebound npuas, qeeb-rebound npuas, thiab cov npuas zoo tib yam yog qhov tsis tau muaj dua li qhov sib xws thiab sib koom ua ke, thiab qhov sib txawv nyob hauv cov tshuaj tiv thaiv.
Ib qho qauv sib npaug rau kev tsim cov tub rog ua ntej ua tsov rog ntawm ob pab tub rog. Noj cov tshuaj tiv thaiv ntawm toluene diisocyanate (TDI) thiab trihydroxy polyether (PPG) ua piv txwv, muaj 1-OH (PPG), 2-OH (PPG), 3-OH (PPG) , 2.4-4-NCO (TDI), 2.4-2 NCO (TDI), 2.6-2 NCO (TDI), 2.6-6 NCO (TDI), H (dej), OH (dej) cuaj reactive tshuaj.
Txawm hais tias thawj zaug ua haujlwm ntawm pawg hydroxyl hauv 1-3 txoj haujlwm ntawm PPG yog tib yam, thaum ib pab pawg hydroxyl reacts, cov dej num ntawm ob pawg hydroxyl yuav poob qis, uas yog hais tias, 33.3 feem pua ntawm PPG raug nqi. Ib yam yog qhov tseeb rau isocyanates, uas ua lub luag haujlwm tseem ceeb hauv kev nce ntawm cov npuas dej vim muaj kev ua haujlwm siab ntawm 2.4-4 TDI thiab nws qhov rhiab heev rau thawj kauj ruam cov tshuaj tiv thaiv dej. Txhawm rau txiav txim siab cov txiaj ntsig ntawm kev ua tsov rog no, ib qho yog cov tub ceev xwm thiab tub rog zoo, uas yog, cuaj cov tshuaj tiv thaiv saum toj no. Lwm qhov yog lub zog uas txhua tus reactant imparts rau pem hauv ntej nqi.
Muaj ob lub ntsiab lus txhawb siab rau cov tub ceev xwm saum toj no thiab cov tub rog kom maj nrawm mus tom ntej. Ib qho yog tias lub luag haujlwm ua tiav tom qab lub zog tam sim ntawd tau ua tiav. Piv txwv li, lub peev xwm muaj peev xwm sau tau thaum hneev taw tag nrho thaum tua ib xub tau hloov mus rau hauv lub zog pib lub zog sai sai thaum hneev tawm. , lub hwj chim no yog paub los ntawm cov mis raw khoom kub (thaum pib cov tshuaj tiv thaiv kub). Lwm qhov yog ua kom nrawm nrawm nrog lub zog, uas zoo li txhim kho lub zog txhaj tshuaj ntawm lub xub ntiag ntawm lub cev. Thaum tus xub raug tua, lub koob tshuaj pib ua haujlwm thiab txuas ntxiv thawb tus xub kom nrawm mus rau pem hauv ntej. Lub zog no yog tsav los ntawm cov catalyst ntawm cov mis (catalyst concentration) uas muab. Yog li wow, dab tsi ntawm qhov kub-kub catalyst yuav tsum tau txo, yuav ua li cas txo nws, thiab nws puas tuaj yeem hloov qee qhov? Nws tsis yooj yim li ntawd.
Nrog lub hwj chim los them rau pem hauv ntej, nws yuav mob taub hau heev rau leej twg ua ke nrog leej twg, uas cuam tshuam nrog kev sib tw thiab kev faib tawm ntawm ntau yam reacting tshuaj vim qhov concentration, kev ua, thiab cov tshuaj tiv thaiv hom. Piv txwv li, kev sib tw ntawm dej thiab polyether hauv cov pab pawg reactive rau TDI, kev sib tw ntawm 2.4TDI thiab 2.6TDI rau dej thiab polyether, kev sib tw ntawm polyether, dej thiab TDI rau cov tshuaj tiv thaiv catalyst, cov nyhuv ntawm catalyst (ua kom lub zog) thiab cov Cov tshuaj tiv thaiv kab mob Kev sib tw ntawm cov nyhuv ntawm qhov kub thiab txias ntawm cov tshuaj tiv thaiv tus nqi, kev sib tw ntawm kev tso cua sov thiab cov cua kub dilution los ntawm cov pa roj, kev sib tw kuj suav nrog cov tshuaj tiv thaiv exothermic ntawm OCO tiam thiab cov tshuaj tiv thaiv ntawm lub cev tshuab tshuab uas gasification tshem tawm cov cua sov, thiab lwm yam. . Nyob rau hauv cov tshuaj tiv thaiv scenario, cov kev sib tw saum toj no yog tag nrho cov staged, uas yog lub hauv paus yog vim li cas rau lub polytropic cov tshuaj tiv thaiv ntawm polyurethane saj zawg zog ua npuas ncauj. Muaj ntau ntau yam thiab nyuaj heev. Yog li wow, nyob rau hauv qhov tseeb ntau lawm, lub sab hauv kub hloov nkhaus thaum lub sij hawm cov tshuaj tiv thaiv yog feem ntau tswj kom standardize ntau yam tshuaj tiv thaiv. Raws li yuav ua li cas txwv tsis pub thim rov qab ntawm cov tshuaj tiv thaiv polymer, nws kuj yog ib qho teeb meem me ntsis.
Tej yam muaj yin thiab yang. Tsuas yog saib cov tshuaj tiv thaiv zoo nrawm nrawm heev, nce exponentially, thiab nws yuav siv sij hawm ntev rau cov tshuaj tiv thaiv kom tawm ntawm kev tswj. Yog li wow, yuav tsum muaj qee yam tiv thaiv nws los ntawm kev nce nws cov tshuaj tiv thaiv. Raws li cov tshuaj tiv thaiv tshwm sim, muaj cov ntsiab lus hauv qab no: qhov concentration ntawm reactants txo qis sai, qhov concentration ntawm cov khoom nce sai, thiab cov pa roj ntau yog sai heev kom dilute cov tshuaj tiv thaiv tshav kub. Nws yuav tsum tau muab sau tseg tias cov nyhuv ntawm cov roj tsim nyob rau hauv lub dilution thiab txo cov concentrations ntawm reactants thiab cov khoom yog heev me me. Cov teeb meem no kuj tau loj hlob exponentially. Nrog rau ib qho kev nce thiab ib qho kev txo qis, peb pom cov tsos ntawm qhov nce tsis tu ncua hauv cov npuas.
Lub microscopic txiav txim qhov macroscopic. Piv txwv li, peb txhua tus paub tias cov txheej txheem ntawm kev tso pa carbon dioxide los ntawm cov tshuaj tiv thaiv dej rau TDI tau muab faib ua ob kauj ruam. Thawj kauj ruam yog tso cov pa roj carbon dioxide, thiab cov kauj ruam thib ob yog los tsim lwm yam tsis muaj roj. Los ntawm daim ntawv cog lus sib cais lub zog, peb tuaj yeem suav tias kwv yees li 70 feem pua ntawm cov cua sov tawm hauv thawj cov tshuaj tiv thaiv, uas yog hais tias, cov pa roj carbon dioxide yuav luag synchronized nrog kev tso tawm ntawm feem ntau ntawm cov cua sov. Yog tias nws thim rov qab, thawj cov tshuaj tiv thaiv tawm 30 feem pua ntawm cov cua sov, thiab cov tshuaj tiv thaiv thib ob tso tawm 70 feem pua ntawm cov cua sov, ces cov tshuaj tiv thaiv ntawm qhov ntsuas macro hloov tag nrho!
Ntau yam kev sib koom ua ke nyob rau hauv ib qho kev sib koom ua ke, thiab nws qhov kev ua tau zoo sab nraud yuav tsum yog qhov nkhaus, xws li macroscopic faib ntawm amine tin catalyst nyob rau hauv qhov sib npaug ntawm cov npuas qhib, seb nws yog kauv upward nkhaus, sine-cosine oscillation nkhaus, lossis tshuaj tiv thaiv. Lub logarithm yog inseparable los ntawm Suav, thiab lub ntuj logarithm yog inseparable.
