Methyl cawv hais txog cov dej cawv monohydric. Qhov no yog ib qho ntawm cov kuab lom txaus ntshai tshaj plaws rau tib neeg, raug mob lom uas tuaj yeem ua rau tuag taus. Nws muaj nyob hauv cov dej cawv tsis tshua muaj cawv.
Lub cev thiab tshuaj tsis zoo ntawm cov cawv methyl
Methyl cawv yog ib yam ua kua uas tsis muaj lub cev uas tsw thiab tsw qab xws li cawv haus cawv. Nws muaj peev xwm yaj nyob hauv ntau cov kuab tshuaj organic: benzene, esters, ntxiv rau dej. Methyl cawv rwj nrog qhov kub ntawm 64 ° C. Txawv rau cov sib xyaw sib xyaw uas nws suav nrog, tus nqi no yuav txawv me ntsis.
Thawj thawj zaug, cov dej cawv methyl tau los ntawm J. Dumas thiab E. Peligo nrog kev pab ntawm cov khoom ua ntoo ua qhuav. Qhov no tau tshwm sim nyob rau thaum xaus ntawm lub xyoo pua puv 19. Twb tau nyob rau xyoo 1923, nws tau pib tsim los ntawm kev lag luam nplai.
Los ntawm cov txheej txheem tshuaj lom neeg, cov dej cawv methyl hais txog monohydric cawv, uas muaj cov khoom ntawm cov tsis muaj zog acid thiab puag. Nws muaj peev xwm ntawm reacting nrog dej vapor nyob rau hauv muaj catalyst (qhov tshwm sim tshwm sim nyob rau hauv qis-zog cov nroj tsuag). Raws li qhov tshwm sim ntawm qhov kev sib txuam no, kev sib xyaw ntawm hydrogen thiab carbon dioxide tau txais. Yog tias cov pa roj carbon dioxide raug tshem tawm ntawm qhov sib tov no, 98% hydrogen tuaj yeem tau txais. Thaum sib cuam tshuam nrog cov hlau nquag (sodium, potassium thiab lwm tus), methylates tau, thiab nrog cov acids, esters yog tau.
Methyl cawv lom
Methyl cawv yog ib yam tshuaj lom rau lub cev. Txawm tias ib qho tshuaj me me (txog 5-10 ml) txaus txaus mus tas li tsis tuaj yeem pom. Nrog rau kev raug mob me, mob taub hau heev thiab xeev siab. Tus neeg ntawd yuav nkees sai sai thiab yuav chim siab. Thaum raug mob lom, tus neeg mob yuav ntxhov siab vim los ntawm kiv taub hau ntau, ntuav thiab mob taub hau. Cov cawv cawv cawv cuam tshuam rau hauv nruab nrab lub paj hlwb thiab tom qab 2-6 hnub ua rau tsis pom kev ib feem lossis ua rau tsis pom kev. Hauv kev lom hnyav heev, tag nrho cov tsos mob saum toj no tau pom, uas sai sai zuj zus mus rau hauv qhov tsis nco qab Cov ntshav siab yuav qis, cov tub ntxhais kawm ua taus pa, thiab ua pa poob qis. Peb ntawm plaub tus neeg muaj txoj sia nyob tom qab haus dej cawv ntau dhau. Lawv tseem nyob tsis taus rau lub neej.
Kev siv cawv methyl
Methyl cawv yog siv hauv kev lag luam rau kev tsim ntau cov organic: acetic acid, methylchlorides, methylamines, thiab tseem siv qee cov tshuaj. Cov dej cawv no muaj tus lej octane siab, uas tso cai rau nws siv los ntxiv rau hauv roj av txhawm rau txhawm rau txuag cov ntaub ntawv raw. Cov thev naus laus zis kom tau txais lwm yam cawv los ntawm nws tab tom tsim kho: tshwj xeeb, cawv ethyl.
