Dab tsi yog cov khoom hauv PVC
May 19, 2018
PVC khoom yog ib hom ntawm cov khoom siv yas hniav, nws yog luv luv rau cov khoom PVC. PVC (Polyvinyl Chloride, PVC) cob yog thermoplastic polymer ua los ntawm cov yas chloride monomer (Vinyl Chloride Monomer, luv luv luv). Nws yog tsim los ntawm polyvinyl chloride cob raws li cov ntaub ntawv tseem ceeb raw, ntxiv ib qho nyiaj ntawm cov tshuaj tiv thaiv, hloov kho, thiab hais txog. Nws yog los ntawm sib tov, calendering thiab nqus tsev vacuum. PVC yog ib qho amorphous polymer uas muaj crystallite ntawm 5% - 10% ntawm crystallinity (175 degrees melting point). Lub zog ntawm lub cev xws li molecular luj, crystallinity thiab softening point ntawm PVC hloov nrog polymerization mob (kub). PVC pob zeb siv los ua cov khoom siv thiab siv cov stabilizers, cov khoom yas, cov xim, cov xim tha xim, hloov kho thiab lwm cov koom haum rau cov hnab yas thiab cov yas hlau uas tsim PVC. PVC cov ntaub ntawv yog ua los ntawm lub cev nyhav, qhov hluav taws kub kub, thermal rwb thaiv tsev, noo noo, hluav taws kub retardancy thiab yooj yim siv. Specifications, xim thiab cov qauv yog ntau yam, thiab lawv yog cov zoo nkauj. Lawv yog cov siv ntau lawm thiab tsim tau lub neej. Piv txwv, PVC dej kav, PVC yas qhov rooj thiab qhov rais, thiab cov khoom ua si yas muaj PVC, xov hlau thiab cables. Vim hais tias ntawm nws cov teeb meem rau tib neeg lub cev, Teb chaws Europe, Nyiv thiab South Kauslim thiab lwm lub teb chaws tau txwv cov khoom nrog PVC li raw cov ntaub ntawv. Qhov zoo tshaj ntawm cov qauv PVC cov khoom pov thawj yog refractory, hnav-resistant, tshuaj corrosion tshuaj thiab tsis muaj roj to. Tsis tas li ntawd, txhua yam khoom siv hluav taws xob, cov khoom hluav taws xob, hluav taws xob rwb thaiv tsev, cov hluav taws kub kub, lub suab nrov thiab kev poob siab yog cov khoom siv ntau yam nrog tus nqi zoo tshaj plaws. Cov defect yog thermal stability thiab tej yam tsis kam, txawm tawv los yog mos PVC nws yog nchuav rau nkig thaum siv. Cov PVC no muaj ob (2 - ethyl hexyl) adipate (DEHA) plasticizer uas tsis pub siv los ntawm cov kev cai hauv lub tebchaws. DEHA tau yooj yim tso rau ntawm qhov kub siab (tshaj 100 degrees centigrade) thiab muaj teeb meem rau kev noj qab haus huv tom qab kis tau rau tib neeg lub cev. Vim hais tias PVC yog yas yas, nws yog ib qho tsim nyog yuav tau ntxiv ntau cov yas yas los kho nws. Plasticizers tau yooj yim tso rau hauv qhov chaw sov so. Yog tias siv DEHA, nws yuav cuam tshuam nrog tib neeg endocrine, ua rau mob qog nqaij hlav cancer, yug menyuam tsis muaj mob tshiab, txo cov txiv neej cov phev, thiab mob hlwb.