Chemistry ntawm kev uaPVCkoom nrog kev noj cov khoom yooj yim tshaj plaws, hu ua monomers, thiab txuas cov monomer molecules ua ke hauv cov txheej txheem polymerization los tsim cov saw ntev molecular hu ua polymers (tseem hu ua macromolecules).
Qhov no yog cov ntaub ntawv ntawm PVC, uas yog tsim los ntawm vinyl chloride monomer, feem ntau paub los ntawm nws thawj VCM los ntawm polymerization. Qee cov monomers muaj xws li cov tshuaj reactive gaseous thiab qee cov monomers tuaj yeem ua rau muaj kev phom sij rau kev noj qab haus huv thaum sib cuag nrog tib neeg. Hauv cov xwm txheej no, lawv tau tsim thiab ua tiav raws li kev tswj hwm nruj los tiv thaiv kev noj qab haus huv, kev nyab xeeb thiab ib puag ncig.
Ntawm qhov tod tes, cov khoom siv polymers xws li PVC yog tsim los ntawm monomers los ntawm polymerization thiab yog cov khoom ruaj khov thiab chemically ruaj khov thiab yog li tsis cuam tshuam rau tib neeg kev noj qab haus huv.VCM yog cov khoom siv raw ntawm PVC thiab yog cov roj ntawm qhov kub thiab txias, tab sis feem ntau yog khaws cia. raws li cov kua hauv qab siab. Ethylene thiab chlorine yog cov khoom siv raw rau PVC.
Los ntawm thermal cracking ntawm naphtha los yog natural gas, qhov yooj yim petrochemical kev lag luam tsim ethylene thiab propylene, thiab lwm yam. Naphtha feem ntau yog muab los ntawm kev lag luam roj av refining, uas siv cov roj crude ua cov khoom noj. Kev lag luam Chlor-alkali tsim cov dej qab zib caustic, chlorine thiab hydrogen los ntawm electrolysis, siv cov ntsev ntsev ua cov khoom siv tseem ceeb.
Nyob rau hauv thawj theem ntawm cov txheej txheem tsim PVC, ethylene thiab chlorine yog tov los tsim ib qho khoom nruab nrab hu ua dichloroethane; Qhov no yog ces hloov mus rau hauv vinyl chloride, lub hauv paus tsev thaiv ntawm polyvinyl chloride los yog PVC. Cov txheej txheem "polymerization" koom nrog vinyl chloride molecules ua ke los tsim PVC chains. Lub PVC ua nyob rau hauv no txoj kev yog nyob rau hauv daim ntawv ntawm ib tug dawb hmoov. Qhov no tsis yog siv ib leeg xwb tab sis yog tov nrog lwm cov khoom los muab cov formulations rau ntau yam khoom.
Cov khoom lag luam feem ntau muaj cov pa roj carbon thiab hydrogen ua lawv cov khoom tseem ceeb. PVC txawv nyob rau hauv uas nws muaj chlorine (kwv yees li 57 feem pua ntawm qhov hnyav) nrog rau cov pa roj carbon thiab hydrogen. Lub xub ntiag ntawm cov tshuaj chlorine hauv cov molecule ua rau PVC tshwj xeeb yog muaj ntau yam, vim nws ua rau nws sib xws nrog ntau yam khoom siv. Cov ntsiab lus chlorine kuj pab ua rau PVC nplaim taws. Nws kuj tseem siv tau los ua "kos npe" kom paub qhov txawv ntawm PVC hauv cov tshuab automated sorting tshuab rau cov yas rov ua dua tshiab. PVC formulations tuaj yeem raug molded los ntawm ntau yam txuj ci thiab siv lub zog me me los ua cov khoom kawg. PVC polymers yog tshuaj ruaj khov, nruab nrab thiab tsis muaj tshuaj lom. xws li cov khoom siv kho mob, nrog rau kev tsim kho, tsheb thiab cable.