Cov txheej txheem synthesis ntawm TPU tuaj yeem muab faib ua ob pawg raws li qhov muaj lossis tsis muaj cov kuab tshuaj: hnyav-dawb bulk polymerization thiab hnyav-raws li kev daws teeb meem polymerization. Bulk polymerization tuaj yeem muab faib ua ib-kauj ruam thiab cov txheej txheem prepolymer raws li cov kauj ruam cov tshuaj tiv thaiv. Cov txheej txheem ib kauj ruam suav nrog kev sib xyaw oligomer diols, diisocyanates, thiab cov saw txuas ntxiv ib txhij los tsim. Cov txheej txheem ib-kauj ruam yog yooj yim thiab yooj yim rau kev khiav lag luam, tab sis nws cov tshuaj tiv thaiv tshav kub yog ib qho nyuaj rau tshem tawm thiab sab tshua tshwm sim. Ib qho polyester raws li thermoplastic polyurethane elastomer tau tsim los siv ib txoj hauv kev. Ua ntej, cov mis mos ntawm polyester polyol thiab saw extender, butanediol, tau hnyav rau hauv lub reactor thiab rhuab mus rau 120 degree rau lub tshuab nqus tsev vacuum. Ceev nrooj ntxiv cov preheated thiab sai do tusyees, ncuav nws mus rau hauv lub preheated thawv, nqus tsev vacuum ntawm 120 degree, thiab ces txias rau 100 degree kom tau ib lub teeb daj translucent polyurethane khoom. Tom qab ntawd, nias nws mus rau hauv cov ntawv xeem ntawm cov xovxwm tiaj tus, thiab cov TPU npaj tau muaj cov cuab yeej ua haujlwm siab thiab damping.
Txoj kev prepolymer suav nrog cov tshuaj tiv thaiv ntawm oligomer diols thiab diisocyanates, tom qab ntawd los ntawm kev sib txuas nrog cov saw qhuav txuas ntxiv nyob rau hauv ib qho me me ntawm cov kab mob catalyst. Cov txheej txheem ntawm cov txheej txheem prepolymer hauv kev tsim khoom yog qhov nyuaj, siv lub zog siab, thiab cov viscosity ntawm cov khoom ua prepolymer yog siab, uas ua rau cov txheej txheem ua haujlwm nyuaj. Txawm li cas los xij, cov khoom siv prepolymer muaj tsawg dua qhov tshwm sim thiab cov khoom ua tau zoo dua li txoj kev ib-kauj ruam.
Raws li qhov txuas ntxiv ntawm cov txheej txheem tshuaj tiv thaiv, nws tuaj yeem muab faib ua ntu ntu thiab txoj kev txuas mus ntxiv. Cov cuab yeej siv ntau lawm rau txoj kev sib tshuam suav nrog cov cuab yeej siv lub tshuab nqus tsev, kho qhov cub, crushing hammers, extruders, thiab lwm yam, uas muaj kev ua haujlwm tsawg, cov khoom tsis sib xws, thiab tsis haum rau cov khoom loj. Yog li ntawd, cov txheej txheem ntau lawm thiab khoom siv tau raug kawm ob qho tib si hauv tsev thiab thoob ntiaj teb. Cov khoom siv txuas ntxiv yog cov tshuaj tiv thaiv extrusion ntau lawm kab, uas feem ntau suav nrog cov khoom siv raw khoom cia tso tsheb hlau luam, cov tshuab nchuav, sib npaug ntxaib ntsia hlau extruders, underwater granulators, sib cais thiab ziab khoom, thiab ntim khoom. Lub ntxaib ntsia hlau txuas ntxiv cov tshuaj tiv thaiv extrusion txoj kev yog tam sim no cov txheej txheem tseem ceeb ntawm kev tsim khoom, nrog kev ua haujlwm siab ntau lawm thiab cov khoom lag luam ruaj khov, haum rau cov khoom loj. Nws tuaj yeem siv rau coatings, elastomers, thiab adhesives.