Terephthalic acid: tshuaj muaj zog, ntau lawm thiab kev siv

2024 Tus sau: Howard Calhoun | [email protected]. Kawg hloov kho: 2023-12-17 10:28

Phthalic acids yog cov neeg sawv cev tseem ceeb ntawm polybasic carboxylic compounds ntawm cov tshuaj tsw qab, sawv cev los ntawm qee cov isomers - ortho-isomer (ncaj qha, phthalic acid), meta-isomer (isophthalic) thiab para-isomer (terephthalic). Tag nrho cov tshuaj ntawm pab pawg no tau siv dav hauv ntau qhov kev lag luam.

Terephthalic acid yog cov xim tsis muaj xim dawb crystalline hmoov uas tau txais thaum lub sij hawm cov tshuaj tiv thaiv ntawm cov kua theem oxidation ntawm para-xylene nyob rau hauv lub xub ntiag ntawm cob alt ntsev ua raws li catalysts. Kev sib cuam tshuam ntawm cov tshuaj no nrog ntau yam cawv ua rau tsim cov tshuaj lom neeg ntawm ether pawg. Dimethyl terephthalate muaj kev siv tau zoo tshaj plaws.

Terephthalic acid kuj tseem siv rau kev sib txuas ntawm polyethylene terephthalate (PET) - pob tshab kub-resistant polymer tau los ntawm cov tshuaj tiv thaiv polycondensation ntawm cov tshuaj no nrog ethylene glycol. Tom qab ntawd los ntawm nwstsim lub raj mis yas, polyester fibers ntawm pab pawg terylene, paub zoo dua nyob rau hauv lub npe "lavsan", nrog rau ntau yam ntim ntim rau kev lag luam khoom noj khoom haus, xov tooj cua Cheebtsam thiab ntau yam khoom siv.

Hais txog nws cov khoom siv tshuaj, terephthalic acid zoo ib yam li monobasic carboxylic compounds. Thaum rhuab los yog nyob rau hauv lub zog ntawm thiaj li hu ua dej-tshem tshuaj, nws yooj yim tsim ntsev, esters ntawm ib tug complex molecular qauv, anhydrides, amides, ob leeg nyob rau hauv ib tug thiab nyob rau hauv ob pawg carboxyl. Tsis tas li ntawd, terephthalic acid nkag mus rau hauv cov tshuaj tiv thaiv esterification, raws li qhov tshwm sim ntawm cov mono- thiab diesters tsim. Thaum cov khoom siv crystalline no tau ua kom sov rau qhov kub ntawm tsawg kawg yog ob puas degrees, decarboxylation tau pom nrog kev tsim ntawm cov tebchaw uas muaj cov pawg carboxyl tsawg dua. Txawm li cas los xij, kev hloov pauv electrophilic nyob rau hauv lub nplhaib deactivated pib nrog kev nyuaj heev.

Phthalic acid yog ib txwm muaj nyob rau hauv cov xim ntsuab ntawm cov nroj tsuag thiab cov noob poppy noob pods. Ntawm nws cov derivatives, qhov tseem ceeb tshaj plaws yog ether compounds dibutyl thiab dimethyl phthalate, uas yog siv los ua plasticizers rau cov khoom siv cellulose, vinyl polymers, thiab roj hmab. Tsis tas li ntawd, dimethyl-, diethyl- thiab dibutylphthalates yog cov khoom tseem ceeb ntawm ntau yam tshuaj tua kab mob.

Y Isophthalic acid yog nquag siv nyob rau hauv kev tsim cov unsaturated polyester resins. Vim tias isophthalates yog cov yas zoo heev. Tab sisterephthalic acid, uas yog siv rau cov synthesis ntawm xws li industrially tseem ceeb tshuaj xws li dimethyl terephthalate thiab polyethylene terephthalate, muaj qhov zoo tshaj plaws daim ntawv thov los ntawm cov pab pawg neeg ntawm benzene-polycarboxylic compounds. Lawv yog siv rau kev tsim cov hlua khi rau ntau yam kev siv tshuab, hlua, conveyor siv, nuv ntses nets, sails, nkoj iav, trawls, roj av thiab roj resistant hoses, zippers, tennis racket hlua thiab ntau ntxiv. Tsis tas li ntawd, knitwear, ntau yam ntaub (crepe, tweed, satin, thiab lwm yam), curtains thiab tulle cov khoom, raincoat, kaus thiab costume cov ntaub ntawv, tsho, stockings, me nyuam cov khaub ncaws yog tsim los ntawm cov ntaub ntawv du, nyob rau hauv zus tau tej cov cov khoom no. yog siv. etc.

Hauv kev xaus, Kuv xav kom nco ntsoov tias tag nrho cov kua qaub ntawm benzene polycarboxylic series yog cov tshuaj phem heev thiab cov tshuaj lom. Yog li ntawd, lawv ib txwm nrog cov ntaub ntawv kev nyab xeeb ntawm cov ntaub ntawv, uas qhia tag nrho cov khoom thiab cov yam ntxwv ntawm cov khoom sib xyaw no, nrog rau cov txheej txheem thiab cov cai rau kev ua haujlwm nrog nws.