Tshuaj thaj chaw ntawm alkenes (olefins)

Olefins - hydrocarbons uas molecule muaj ib tug muab ob npaug rau daim ntawv cog lus. Tej zaum tam sim no tebchaw hu ua hydrocarbons ethylene series. Lub ob daim ntawv cog lus nyob rau hauv lub molecule yog yooj yim nrhiav tau los ntawm spectral tsom xam.

Lub cev thaj chaw ntawm alkenes

Tus thawj peb cov tswv cuab ntawm lub homologous series ntawm alkenes - gases. Los ntawm lub thib tsib mus rau lub thib kaum rau - kua, siab molecular yuag alkenes - khib nyiab. Nrog nce thiab nce kom hydrocarbon saw ntev ib kub npau npau taw tes tshuaj. Nyob rau hauv laboratory tej yam kev mob, cov tshuaj yuav tsum tau nyob rau hauv ob peb txoj kev: los ntawm lub dehydrogenation ntawm alkenes los ntawm ntes roj av, dehydrogenation ntawm alcohols.

Ntes ntawm cov roj - muaj txoj kev ua unsaturated hydrocarbons. Raws li ib tug tshwm sim, thermal ntes roj rhuab mus 750 degrees, lub alkane hydrocarbon cev pob txha yog tawg:

S30N62 → S15N30 + S15N32

Dehydrogenation ntawm alkanes. Qhov no txoj kev yog nqa tawm ntawm ib tug kub ntawm txog 600 degrees. Nyob rau hauv cov tej yam kev mob, lub nyeem hydrocarbon molecule los ntawm H atoms yog cleaved tsim alkenes, piv txwv li: → S5N12 S5N10 + H2.

Lub cev qhuav dej ntawm alcohols. Monohydric alcohols interacting nrog sulfate acid daim ntawv alkenes, piv txwv li: S4N9ON → C4H8 + H2O.

Tshuaj thaj chaw ntawm alkenes muaj feem xyuam rau cov muaj nyob rau hauv lawv cov molecule ib tug muab ob npaug rau daim ntawv cog lus. Lub electron ceev ntawm lub atoms, ib tug muab ob npaug rau daim ntawv cog lus yog siab tshaj uas nyob nruab nrab lub C atoms kev cob cog rua ntawm ib bonds. Lub ntsiab yam ntawm cov tshuaj tiv thaiv, cov uas tuaj alkenes - accession, nrog los ntawm ib tug pi-so vim tus tsim ntawm ob tug tshiab sigma bonds. Olefins nkag mus rau hauv lub polymerization cov tshuaj tiv thaiv, uas yog tseem nrog cleavage ntawm ob bonds.

Tshuaj thaj chaw ntawm alkenes: koom halides

Olefins nkag muab lawv tus kheej rau hydrogen molecule halide, yog li txoj kev monogalogenoproizvodnye (e.g. S10N20 S10N21S1 → HC1 +). Thaum uas txuas mus rau alkenes tsim H2O nyeem monohydric alcohols (S10N20 + H2O → S10N21ON).

hlawv alkenes

Thaum siab kub nyob rau hauv O2 olefins yog nkag oxidized (hlawv) rau C02 thiab H20. Alkenes, interacting nrog poov tshuaj permanganate tsim tau ib dihydric alcohols (glycols).

Tshuaj thaj chaw ntawm alkenes: olefin polymerization

Nthuav hydrocarbons muaj ib tug ntau dua ib txwm mus polymerization cov tshuaj tiv thaiv. Feem ntau, lub polymer - yog ib tug ntev saw nrog rov qab ua dua structural units (monomers). Qhov no txoj kev yuav tsum pib nyob rau hauv ob peb txoj kev, tab sis nyob rau hauv Feem ntau nws yog ib cov saw, thiab koom mus rau ib tug dawb radical, cationic los yog anionic dab.

Tshuaj thaj chaw ntawm alkenes: cationic polymerization

Qhov no hom ntawm cov tshuaj tiv thaiv yog tshwmsim los ntawm acids. Proton koom olefin, txoj kev ua ib tug carbocation. Ces raws li tus kawg xwb rau qhov pi-sitemu lwm molecule thiab cov ntaub ntawv alkene carbocation nrog ib tug ntev saw, uas noj cov nram qab no olefin molecule, etc. Raws li ib tug tshwm sim, lub ncaws ntawm ib tug proton los yog lwm yam txheej txheem, tus "quenching" xwb carbocation, ib qhib Circuit Court tshwm sim. Thaum anionic polymerization novice anion yog tsim los ntawm nucleophilic nres ntawm lub anion x- olefin. Thaum txuas proton saw so. Nws yuav tsum tau muab sau tseg tias free-radical polymerize feem ntau ntawm unsaturated hydrocarbons. Qhov no txoj kev yuav tsum pib H202, organic peroxides, hydroperoxides, etc. Qhib Circuit Court tshwm sim vim recombination ntawm radicals. Nyob rau hauv tej rooj plaub, rau alkene polymers siv copolymerization cov tshuaj tiv thaiv. Nyob rau hauv lub copolymerization, ib tug polymer muaj ntau qhov chaw, alternating nyob rau hauv lub macromolecule nyob rau hauv ib txoj kev. Cov tshuaj tiv thaiv cov khoom tau copolymer. Lub cev thiab txhua yam khoom ntawm lub tam sim no lub tebchaw yog txiav txim los ntawm qhov kev txiav txim ntawm alternation ntawm elementary units, thiab lub hom thiab cov nyiaj uas lub monomers muaj nyob rau hauv lub polymer saw.