Purification ntawm polyurethane prepolymer
May 05, 2021
1. Zoo: Siv 10% cov tshuaj uas tau npaj tshiab poov tshuaj iodide thiab 10ml polyurethane prepolymer los co, thiab cov peroxide yuav daj-xim av.
2. Quantification: ntxiv 6 ml ntawm acetic acid + 4 ml ntawm chloroform + 1 g ntawm poov tshuaj iodide rau 50 ml ntawm polyurethane prepolymer, muab tso rau hauv qhov tsaus rau 5 feeb, thiab titrate nrog 0.1N sodium thiosulfate tov kom txog thaum nws tsis muaj xim. Qhov feem pua ntawm peroxide yog: NXVX0.7 / G qhov twg N thiab V yog qhov sib npaug concentration thiab ntim (ml) ntawm sodium thiosulfate feem, thiab G yog qhov hnyav (g) ntawm polyurethane prepolymer.
3. Txoj kev tshem tawm:
A. Kev tshem tawm dej: siv anhydrous calcium oxide, molecular sieve, calcium hydride.
B. Kev tshem tawm ntawm peroxide: siv sodium hydroxide, sodium borohydride, calcium hydride, tooj liab chloride tov, ferrous sulfate tov. Tom qab kev sim, sodium hydroxide tsuas tuaj yeem ua lub ntsej muag lub ntsej muag ntawm kev txiav txim siab ntawm peroxides, thiab tsis tuaj yeem tshem tawm cov peroxides tiag tiag, yog li nws tsis siv; thiab cov tshuaj tooj liab chloride thiab cov tshuaj ferrous sulfate yog lub cev qhuav dej vim lwm qhov kev ua kom pom tseeb ntawm qhov kev sim no yog ntxiv cov tshuaj no. Cov dej loj loj tsis haum.
