(PVC) inonzi thermoplastic yakakurumbira isinganhuhwi, yakasimba, brittle, uye kazhinji ichena muruvara.Parizvino yakaverengerwa sepurasitiki yechitatu inonyanya kushandiswa pasi rose (kuseri kwe polyethylene uye polypropylene).PVC inonyanya kushandiswa mukugadzira pombi uye madhiraini maapplication, kunyangwe ichitengeswawo muchimiro chepellets kana seresin muhupfu hwayo.
Kushandiswa kwePVC
Kushandiswa kwePVC kwanyanya muindasitiri yekuvaka dzimba.Inogara ichishandiswa sechinotsiva kana imwe nzira yepombi dzesimbi (kunyanya mhangura, galvanized simbi, kana simbi yakakandwa), uye mune zvakawanda zvinoshandiswa apo ngura inogona kukanganisa kushanda uye kuwedzera mari yekugadzirisa.Pamusoro pezvikumbiro zvekugara, PVC inoshandiswawo nguva nenguva kumapurojekiti emanisipala, maindasitiri, echiuto, uye ekutengesa.
Kazhinji, PVC iri nyore zvikuru kushanda nayo pane pombi yesimbi.Inogona kuchekwa kusvika kuhurefu hunodiwa nemaoko maturusi akareruka.Mafittings nemapombi epombi haafanire kusungirirwa.Mapombi akabatana nekushandiswa kwemajoini, simende inonyungudutsa, uye maglue akakosha.Imwe mukana wePVC ndeyokuti zvimwe zvigadzirwa izvo mapurasitiki akawedzerwa zvakapfava uye zvakanyanya kuchinjika, zvinopesana nekuomarara, zvichiita kuti zvive nyore kuisa.PVC inoshandiswa zvakanyanya mune ese ari maviri anochinjika uye akaomesesa mafomu se insulation yemagetsi emagetsi senge waya netambo.
Muindasitiri yezvehutano, PVC inogona kuwanikwa muchimiro chekudyisa machubhu, mabhegi eropa, intravenous (IV) mabhegi, zvikamu zvedialysis zvishandiso, uye zvimwe zvinhu zvakawanda.Zvinofanira kucherechedzwa kuti kushandiswa kwakadaro kunogoneka chete kana phthalates-kemikari inobudisa magiredhi anochinjika ePVC nemamwe mapurasitiki-akawedzerwa pakuumbwa kwePVC.
Zvigadzirwa zvevatengi zvakajairika senge mabhachi emvura, mabhegi epurasitiki, matoyi evana, makadhi echikwereti, mapombi egadheni, magonhi nemahwindo, uye maketeni eshawa-kududza zvinhu zvishoma zvaungangowana mumba mako-zvinogadzirwawo kubva kuPVC mukati. imwe fomu kana imwe.
PVC yakagadzirwa sei
Kunyange zvazvo mapurasitiki ari zvinhu zvakagadzirwa nevanhu, izvo zviviri zvinopinda muPVC-munyu nemafuta-zvakagadzirwa.Kuti uite PVC, chinhu chokutanga chaunofanira kuita ndechekuparadzanisa ethylene, gasi rinowanikwa kubva kune izvo zvinozivikanwa se "feedstock."Muindasitiri yemakemikari, petroleum ndiyo inodyira yesarudzo yemakemikari akawanda, anosanganisira methane, propylene, uye butane.(Zvekudya zvechisikigo zvinosanganisira algae, inova chikafu chinozivikanwa chemafuta ehydrocarbon, pamwe nechibage uye nzimbe, izvo zvese zviri zviviri zvimwe zvekudya zve ethanol.)
Kuparadzanisa ethanol, petroleum yemvura inopisa muchoto cheupfu uye inoiswa pasi pekumanikidzwa kwakanyanya (maitiro anonzi thermal cracking) kuunza shanduko muhuremu hwemakemikari emakemikari ari mudura.Nekugadzirisa huremu hwayo hwemamorekuru, ethylene inogona kuzivikanwa, kuparadzaniswa, uye kukohwa.Kana izvozvo zvangoitwa, inotonhodzwa kusvika pairi mvura.
Chikamu chinotevera chemuitiro wacho chinosanganisira kubvisa chikamu cheklorini kubva mumunyu mumvura yegungwa.Nokupfuudza simba remagetsi rakasimba kuburikidza nemushonga wemvura yemunyu (electrolysis), imwezve electron inowedzerwa kune chlorine molecules, zvakare, ichibvumira kuti ionekwe, iparadzaniswe, uye ibudiswe.
Iye zvino wava nezvikamu zvikuru.
Kana ethylene neklorini zvasangana, makemikari anoita zvinogadzira zvinogadzira ethylene dichloride (EDC).Iyo EDC inopinda yechipiri yekupisa kupisa maitiro, iyo zvakare, inogadzira vinyl chloride monomer (VCM).Tevere, iyo VCM inopfuudzwa kuburikidza necatalyst-ine reactor, izvo zvinoita kuti mamorekuru eVCM abatanidze pamwechete (polymerization).Kana iwo mamorekuru eVCM akabatana, iwe unowana PVC resin-hwaro hweese mavhinyl compounds.
Tsika yakaoma, inochinjika, kana yakasanganiswa vinyl makomisheni inogadzirwa nekusanganisa resin neakasiyana magadzirirwo eplasticizers, stabilizers, uye modhifita kuti uwane zvinhu zvinodiwa zvinosanganisira zvese kubva kuruvara, magadzirirwo, uye kuchinjika kusimba mukusimba kwemamiriro ekunze uye UV mamiriro.
Zvakanakira zvePVC
PVC chinhu chinodhura chakaderera, chakareruka, chinoumbika, uye kazhinji chiri nyore kubata nekuisa.Kuenzaniswa nemamwe marudzi emapolymers, maitiro ayo ekugadzira haagumiri pakushandiswa kwemafuta asina kuchena kana gasi rechisikigo.(Vamwe vanopokana kuti izvi zvinoita kuti PVC ive "purasitiki inogadzika" sezvo isingaenderane nemhando dzisingaperi dzesimba.)
PVC zvakare yakasimba uye haina kukanganiswa nekuora kana mamwe maitiro ekuora, uye nekudaro, inogona kuchengetwa kwenguva yakareba.Magadzirirwo ayo anogona kushandurwa nyore nyore kuita akasiyana mafomu ekushandisa kune akasiyana maindasitiri uye maapplication, inova yekuwedzera yekuwedzera.PVC inewo kugadzikana kwemakemikari, chinhu chakakosha kana zvigadzirwa zvePVC zvichiiswa munzvimbo dzine marudzi akasiyana emakemikari.Hunhu uhu hunovimbisa kuti PVC inochengetedza zvimiro zvayo pasina kuita shanduko huru kana makemikari akaunzwa.Zvimwe zvakanakira zvinosanganisira:
● Biocompatibility
● Kujeka uye kubuda pachena
● Kupokana nekemikari kusagadzikana kuputika
● Low thermal conductivity
● Inoda zvishoma kana kusagadziriswa
Se thermoplastic, PVC inogona kushandiswazve uye kushandurwa kuita zvigadzirwa zvitsva zvemaindasitiri akasiyana, kunyangwe nekuda kweakasiyana maumbirwo anoshandiswa kugadzira PVC, haisi nguva dzose iri nyore kuita.
Kuipa kwePVC
PVC inogona kunge iine 57% chlorine.Kabhoni—inotorwa mupetroleum—inowanzoshandiswa mukugadzirwa kwayo.Nekuda kwehupfu hunogona kuburitswa panguva yekugadzira, kana ichinge yaiswa mumoto, kana kuti ichiparara mumarara, PVC yakanzi nevamwe vaongorori vezvokurapa uye vanoongorora zvakatipoteredza se "chepfu yepurasitiki."
Zvehutano zvine chekuita nePVC hazvisati zvave kuratidzwa nenhamba, zvisinei, chepfu iyi yakabatana nemamiriro ezvinhu anosanganisira asi asina kuganhurirwa kugomarara, kukanganisa kwekukura kwe fetal, kukanganisa kwe endocrine, asthma, uye kushomeka kwemapapu.Nepo vagadziri vachinongedzera kuPVC yakakwira munyu seyakasikwa uye isingakuvadzi, sainzi inoratidza kuti sodium-pamwe nekuburitswa kwe dioxin uye phthalate-ndizvo zvinogona kuita kuti pave nengozi yezvakatipoteredza uye yehutano PVC.
Ramangwana rePVC Plastiki
Kunetseka pamusoro penjodzi dzine chekuita nePVC uye zvakakurudzira tsvakiridzo yekushandiswa kwenzimbe ethanol yekudyisa kwete naphtha (mafuta anopfuta anowanikwa nekuoma distillation yemarasha, shale, kana petroleum).Zvimwe zvidzidzo zviri kuitwa pabio-based plasticizers nechinangwa chekugadzira dzimwe nzira dzisina phthalate.Nepo zviyedzo izvi zvichiri mumatanho ekutanga, tariro ndeyekugadzira nzira dzakasimba dzePVC kudzikisira kukanganisa kunokanganisa hutano hwevanhu uye nharaunda panguva yekugadzira, kushandisa, uye kuraswa matanho.
Nguva yekutumira: Kubvumbi-07-2022