Plastiki ndechimwe chezvinhu zvinonyanya kushandiswa nevanhu kugadzira huwandu hukuru hwezvigadzirwa, senge mabhodhoro, matoyi, midziyo nezvimwe. Nekudaro, hapana mhando imwe chete yadzo, asi kune yakakura kupatsanurwa kwemapurasitiki atichakuratidza mune ino chinyorwa. Tinokukumbira kuti urambe uchiverenga.
Plastic Classification
Pakutanga kuona, kana iwe ukashanyira nzvimbo dzose mumba mako kana muhofisi, uchaona zvakasiyana-siyana zvezvigadzirwa zvakagadzirwa nepurasitiki. Iyo pachayo, plastiki, sezvakambotaurwa, ndeimwe yezvinhu zvakanyanya kushandiswa munyika pakugadzira marudzi ese ezvigadzirwa zvinogona kufungidzira. Zviri nyore kuisa zvinhu zvose se "plastiki." Nekudaro, kupatsanurwa kwemapurasitiki kunowanzo kubata pamusoro pemhando 7 dzeidzi dzaunofanira kuziva nezvadzo. Rondedzero yakazara yemapurasitiki inosanganisira:
Polyethylene terephthalate (PET kana PETE)
Iyo inogadzirwa ne polymerization ye ethylene glycol uye terephthalic acid. Ethylene glycol imvura isina ruvara inotorwa kubva muethylene, uye terephthalic acid icrystalline yakasimba inotorwa kubva muxylene. Kana inopisa pamwe chete pasi pesimba remakemikari anokonzeresa, ethylene glycol uye terephthalic acid inogadzira PET muchimiro chekunyunguduka kwe viscous kunogona kupepetwa zvakananga kuita fiber kana kusimba kuti iwedzere kugadziridzwa sepurasitiki.
Kutaura nemakemikari, ethylene glycol idiol, doro rine molecular structure ine maviri hydroxyl (OH) mapoka, uye terephthalic acid inonhuhwirira dicarboxylic acid, asidhi ine molecular structure ine hombe ine mativi matanhatu (kana anonhuwirira) uye mapoka maviri e-carboxyl (CO 2 H). Pasi pesimba rekupisa uye zvinokonzeresa, mapoka ehydroxyl necarboxyl anoita kuti aumbe esters (CO-O), anoshanda semakemikari bond anobatanidza akasiyana maPET mayuniti mumapolymers akareba. Mvura ndeyezve byproduct.
Ndiyo purasitiki yakashandiswa zvakare. Zvisinei, muUnited States, inenge 20 muzana chete yezvinhu zvacho ndiyo inoshandiswa patsva. PET mabhodhoro uye midziyo zvinowanzonyungudutswa pasi uye kupepetwa kuita mafiber eupholstery kana rugs. Kana yakaunganidzwa muchimiro chakachena, PET inogona kudzokororwa kumashandisirwo ayo epakutanga, uye nzira dzakagadzirwa kuti dziputse iyo polima pasi mumakemikari ayo ekutanga kuitira kuti igadzirise zvakare muPET. Iyo yekudzokorora kodhi nhamba yePET ndeye 1.
High density polyethylene (HDPE)
Iyo inogadzirwa pakudziya kwakadzika uye kumanikidzwa neZiegler-Natta impellers uye activated metallocene kana chromium oxide (inozivikanwa sePhillips catalyst). Kushaikwa kwebranching muchimiro chayo kunobvumira cheni dzepolymer kuti dzinyatsozara, zvichiita kuti pave nedense, yakanyanya crystalline zvinhu zvine simba rakawanda uye kuoma kuri pakati nepakati. Nekunyungudika kunodarika 20°C (36°F) yakakwirira kudarika LDPE, inokwanisa kushingirira kuratidzwa kakawanda ku120°C (250°F) kuitira kuti isabatwe.
Kune rumwe rutivi, zvinogona zvakare kutaurwa kuti zvigadzirwa zvinogadzirwa nemhando iyi yemhando yepurasitiki zvinosanganisira mabhodhoro akaumbwa emukaka uye edzimba dzekuchenesa; kuputika kwepfuti yemabhegi ezvekudya, mafirimu ekuvaka uye pulp yekurima; uye majekiseni akaumbwa mabhakiti, mavharo, makesi emidziyo uye matoyi. Mukati mechikamu chekudzokorodza, rudzi urwu rwepurasitiki runogona kutsanangurwa neinotevera enumeration: 2.
Polyvinyl chloride (PVC)
Irwo rudzi rwekubuda kunogadzirwa ne polymerization yevinyl chloride. Chechipiri chete kune polyethylene pakati pepurasitiki mukugadzira uye kushandiswa. Inoshandiswa mumhando dzakasiyana-siyana dzezvigadzirwa zvepamba uye zvemabhizimisi, kubva kumvura inonaya uye maketeni ekugezera kusvika kumahwindo emahwindo uye pombi dzemukati. Ipurasitiki yakaoma, isingaremi mune yayo yakachena fomu, inogadzirwawo mune inoshanduka "plasticized" fomu. Mukati mezita rinoshandiswa kudzokorodzazve, rudzi urwu rwekugadzika kwepurasitiki rinotora chechitatu.
Yakagadzirwa neFrench chemist Henri Victor Regnault muna 1835 uyezve neGerman kemist Eugen Baumann muna 1872, asi yakangove nemvumo muna 1912, apo mumwe wemakemikari weGerman, Friedrich Heinrich August Klatte, akashandisa chiedza chezuva kutanga polymerization yevinyl chloride. . Iko kushandiswa kwekutengeserana kwepurasitiki pakutanga kwakaganhurirwa nekuoma kwayo kwakanyanya; zvisinei, muna 1926, kuedza kwakaitwa kuti dehydrohalogenate iri muzinga rinopisa rinonyungudutsa kuti riwane unsaturated polymer inogona kubatanidza rabha nesimbi.
Kune rimwe divi, aive Waldo Lunsbury Semon akagadzira plasticized PVC, ine inert uye inochinjika chigadzirwa chaive nebasa rekubudirira kwekutengeserana kwepolymer. Pasi pezita remhando yeKoroseal, yakashandura purasitiki kuita zvisimbiso zvinobata-bata, insulation yetambo dzemagetsi, uye zvigadzirwa zvemachira akavharwa. Kumwe kwekushandiswa kunonyanya kuzivikanwa kwepurasitiki kwakatanga muna 1930, apo Union Carbide neCarbon Corporation dzakabudisa Vinylite, rimwe divi rakazopedzisira rava kushandiswa pamarekodhi egiramufomu muUnited States.
Yakachena PVC inowana kushandiswa mukutengesa kwechivako, uko kuoma kwayo, simba, uye kudzivirira moto kunobatsira mumapombi, madhaidhi, siding, gonhi nemahwindo. Iyo zvakare inoputika yakaumbwa kuita mabhodhoro akajeka uye akajeka. Nekuda kwekuoma kwayo, inofanirwa kuburitswa kana kuumbwa pamusoro pe100 ° C, tembiricha yakakwira zvakakwana kuti itange kuparara kwemakemikari (kunyanya, kubuda kwehydrogen chloride). Kuora kunogona kudzikiswa nekuwedzera zvinodzikamisa, izvo zvinonyanya kusanganiswa nesimbi senge cadmium, zinc, tin, kana lead.
Low density polyethylene (LDPE)
Inogadzirwa kubva kuethylene gasi pakumanikidzwa kwakanyanya (kusvika 350 megapascals kana 50.000 pounds per square inch) uye tembiricha yepamusoro (kusvika kunosvika 350 ° C kana 660 ° F) pamberi pevanotanga ngura. Aya maitiro anoburitsa chimiro chepolymer chine matavi akareba uye mapfupi. Nekuti matavi anodzivirira mamorekuru epolyethylene kuti asabatana kuita hurongwa hwakaoma, hwakaomarara hwekristaro, LDPE chinhu chinochinjika. Kunyungudika kwayo kunosvika 110°C kana 230°F.
Kana tichitaura zvezvishandiso zvikuru kana zvigadzirwa zvinogona kugadzirwa kuburikidza nerudzi urwu mukati mechikamu chepurasitiki, zvinogona kutaurwa kuti iyo inonyanya kushandiswa ndeyekurongedza mafirimu, marara uye mabhegi ekutenga, mulch yekurima, kusungirirwa kwetambo. uye waya, kusvina mabhodhoro, matoyi. nezvinhu zvemumba. Kufanana neakawanda eese mapurasitiki mukati mechikamu, kana adzokororwa ane nhamba, mune iyi kesi ndeye 4.
Polypropylene (PP)
Igasi rinosanganiswa rinowanikwa nekupisa kwemafuta ethane, propane, butane uye naphtha chikamu chepetroleum. Kufanana ne ethylene, ndeye "yepasi olefins," kirasi yemahydrocarbons ayo mamorekuru ane peya imwechete yeatomu kabhoni inobatanidzwa nekaviri bond. Chimiro chemakemikari yepropylene molecule ndeye CH2 = CHCH3. Nekudaro, pasi pechiito chepolymerization catalysts, iyo kaviri chisungo chinogona kutyorwa uye zviuru zvepropylene mamorekuru anobatana pamwechete kugadzira polymer cheni (hombe yakawanda-unit molecule).
Kuwanda kwekugadzirwa kwepolypropylene kunorukwa nekusanganiswa kuita fiber, iyo inoshandiswa mumidziyo yemumba, senge upholstery uye machira emukati nekunze. Kune zvakare akawanda maindasitiri ekupedzisira mashandisirwo, anosanganisira tambo uye twine, anoraswa nonwovens emanapukeni uye zvekurapa zvikumbiro, uye nonwovens yekudzikamisa nekusimbisa ivhu mukuvaka nekugadzira migwagwa. paving. Aya maapplication anotora mukana wekuoma kwepolymer, elasticity, kusamira kwemvura uye kusagadzikana kwemakemikari. Munyika yekudzokorodza, iyi nhengo yeplastics classification ndeye 5.
Polystyrene kana Styrofoam (PS)
Iyi ine brittle uye yakaoma thermoplastic resin inogadzirwa kubva ku styrene (CH2 = CHC6H5). Styrene, inozivikanwawo se phenylethylene, inogadzirwa nekuita ethylene nebenzene pamberi pealuminium chloride kugadzira ethylbenzene, iyo inobva yadhirojeni kuti ibudise clear liquid styrene. Styrene monomer is polymerized uchishandisa emahara radical intiators zvakanyanya muhuwandu uye kumiswa maitiro, kunyangwe emulsion uye nzira dzemhinduro dzinoshandiswa zvakare.
Foamed polystyrene inogadzirwa kuita insulation, kurongedza chikafu, uye midziyo yakaita semakapu ekunwa, makatoni emazai, uye ndiro dzinoraswa nematireyi. Solid polystyrene zvigadzirwa zvinosanganisira jekiseni molded cookware, audio cassette holders uye compact disc packaging makesi. Zvikafu zvakawanda zvinochengeterwa mumatireyi akajeka eiyi vacuum derivative, nekuda kweiyo zvinhu yakakwira gasi permeability uye yakanaka kutapurirana kwemhute yemvura. Inoiswa nhamba 6 muhuwandu hwemapurasitiki mukudzokorodza.
mapurasitiki akasiyana-siyana
Iyi yekupedzisira kupatsanurwa kwemapurasitiki, isu tichawana ese ayo marudzi asina kukwanisa kuiswa mukati memirayiridzo yezvambotaurwa. Muzviitiko izvi tinogona kuwana mimwe mienzaniso yakadai seAcrylonitrile Butadiene Styrene, fiberglass, nylon, pakati pevamwe vakawanda. Ese mapurasitiki aya anoumba boka guru iri anowanzo zivikanwa mukati mezvekudzokorodza paramita ane nhamba 7.
Polycarbonate (PC)
Iyo PC yakaunzwa muna 1958 neBayer AG kuGermany uye muna 1960 neGeneral Electric Company muUnited States. Sezvakagadzirwa nemakambani aya, PC inogadzirwa kuburikidza nepolymerization reaction pakati pebisphenol A, mvura inopisa inotorwa kubva kubenzene, uye phosgene, gasi rinoita zvakanyanya uye rine muchetura rinowanikwa nekuita carbon monoxide neklorini. Mapolymers anozobuda (mamorekuru marefu ane mayunitsi akati wandei) anosanganisira anodzokorora mayunitsi ane maviri anonhuwirira zvindori (benzene) uye akabatana nemapoka ester (CO-O).
Kunyanya nekuda kwezvindori zvinonhuhwirira zvakanyudzwa muketani yepolymer, PC ine kuomarara kwakasiyana. Iriwo pachena zvikuru, richibvumira inenge 90 muzana yechiedza chinooneka kupfuura. Kubva pakati pemakore ekuma1980, chivakwa ichi, chakasanganiswa neakanakisa kuyerera zvivakwa zvepolymer yakanyungudutswa, yakawana kushandiswa kuri kuwedzera mukuumba jekiseni reCD. Nekuda kwekukwirira kwayo kwakanyanya kudarika mapurasitiki mazhinji, mabhodhoro mahombe emvura, mahwindo asingaputsike, nhovo dzekuputsika, uye ngowani dzekuputsika zvinogadzirwawo.
Polylactic asidhi (PLA)
Ndiyo inonyanya kushandiswa ecological polymer uye biodegradability ndiyo yakakosha pamusika. Parizvino inoshandiswa mumafirimu ekurongedza kwenguva pfupi, midziyo, zvigadzirwa zvechikafu uye mabhodhoro. Iyo zvakare inovimbisa biopolymer yeakasiyana maapplication mumunda webiomedical, anoshandiswa kugadzira maimplants nemidziyo yakavakirwa pabiological masosi, pamwe nemasutu, screws uye scaffolds. Zvakare semutakuri wezvinodhaka. Iine simba guru rekutsiva polycarbonate (PC), kunyanya mukugadzirwa kwemagetsi emagetsi, sezvo mutengo wayo wakaderera.
Acrylics
Imwe yemhando iyo inowira mukati meiyo classification yemapurasitiki ndeaya ese anotora kubva kune acrylic makomponi. Aya ndiwo chero ekirasi yemapurasitiki ekugadzira, resin, uye mafuta anoshandiswa kugadzira zvigadzirwa zvakawanda. Nekusiyanisa mareagents ekutanga uye maitiro ekugadzira, chinhu chinogona kugadzirwa chakaoma uye chakajeka, chakapfava uye elastic, kana viscous fluid. Acrylic makomisheni anoshandiswa kugadzira optical uye maumbirwo castings, zvishongo, zvinonamira, coating coating, uye textile fibers.
Acrylonitrile Butadiene Styrene (ABS)
Imhando yemhando yemapurasitiki anogadzirwa ne emulsion kana yakawanda polymerization yeacrylonitrile uye styrene pamberi pe polybutadiene. Izvo zvakanyanya kukosha zvimiro zvainazvo ndezvekupikisa kwayo uye kusimba. Uyezve, inowanzotsanangurwa nezvinhu zvitatu zvikuru: fluidity, kupisa kupisa, uye kukanganisa kwekudzivirira. Styrene monomer inopa ABS yakanaka machinability, acrylonitrile inopa kuomarara, kemikari uye kudzivirira kupisa, nepo butadiene inoita kuti chigadzirwa chiome uye chiwedzere kunyungudika kunyangwe pakudziya kwakaderera.
Kuchinja kwehuwandu hwezvinhu zvinoumba rudzi urwu rwepurasitiki zvinhu kana kuwedzerwa kwezvimwe zvinowedzera zvinobvumira madhigirii akasiyana-siyana ezvivakwa zvakananga kugadzirwa. Kune rumwe rutivi, zvinogona kutaurwa kuti ine zvishoma zvinopesana nemamiriro ekunze uye ndicho chikonzero inokurudzirwa kuishandisa chete mumba. Pamusoro pezvo, zvinofanirwa kucherechedzwa kuti kana uchida kushanda neichi chinobva, unoda tembiricha inogona kubva -20 °C kusvika + 80 °C.
Fibglass
Girazi faibha dzaive shoma kudarika tsvarakadenga kusvika kuma1930s, apo zvivakwa zvavo zvekupisa uye zvemagetsi zvekudzivirira zvakakosheswa uye nzira dzakagadzirwa kuti dzigadzire magirazi anoenderera mberi. Kugadzirwa kwemazuva ano kunotanga negirazi remvura rinowanikwa zvakananga kubva muchoto chekunyungudusa girazi kana nekugadziridza magirazi akagadziridzwa. Kuti ibudise faibha inoenderera mberi, mvura yacho inopinzwa mugomba, chigadziko chinoboborwa nemazana emapfumbu akatsetseka apo mvura yacho inobuda iri mujeti dzakanaka.
Masimba ekusimbisa anounganidzwa mune imwe tambo, iyo inokuvadzwa pacoil. Tambo dzacho dzinogona kumonwa kana kuti kupetwa kuita shinda, kurukwa kuita jira, kana kuti kucheka kuita zvidimbu zvidiki zvozosungirirwa mumameti. Staple fibers kazhinji kazhinji inogadzirwa mukutenderera, umo hova dzakanaka dzegirazi dzinokandwa nemumakomba ari paturntable, dzobva dzaputswa nekupeperetswa nejeti yemhepo kana chipfunga. Mafiibha anoungana pane chinotakura zvinhu uye anoshandurwa kuita makushe, machira kana machira.
Iyo yakanakisa inopisa uye acoustic insulator, fiberglass wool inowanzoshandiswa muzvivakwa, midziyo, uye pombi dzemvura. Girazi filaments uye tambo zvinowedzera simba remagetsi uye resistivity kune akaumbwa epurasitiki zvigadzirwa senge recreational boat hulls, mota nhengo dzemuviri, uye dzimba dzeakasiyana emagetsi evatengi. Machira egirazi anoshandiswa semagetsi ekudzivirira uye semabhandi ekusimbisa mumataya emotokari.
Zvinhu zvenaironi
Icho chero chekugadzira epurasitiki zvinhu izvo zvinogadzirwa kubva kune yakakwira molecular weight polyamides uye kazhinji, asi kwete nguva dzose, inogadzirwa sefayibha. Yakagadzirwa kumakore ekuma1930 nechikwata chekutsvagisa chaitungamirwa nenyanzvi yemakemikari yekuAmerica Wallace H. Carothers, aishandira EI du Pont de Nemours & Company. Kubudirira kugadzirwa kwefaibha inobatsira nemakemikari synthesis kubva mumisanganiswa inowanikwa zviri nyore mumhepo, mvura, uye marasha kana mafuta kwakakurudzira kuwedzera kwepolymer research uye zvakaita kuti mhuri yepurasitiki iwedzere kukura.
Naironi inogona kudhonzwa, kuumbwa, kana kupfuudzwa nemitsara yekunyunguduka kana mhinduro kugadzira shinda, filaments, bristles, kana mashizha ekugadzira shinda, machira, netambo; uye inogona kuumbwa kuita zvigadzirwa zvakaumbwa. Iine kupikisa kwepamusoro kupfeka, kupisa uye zvigadzirwa zvemakemikari. Yakatambanudzwa nechando, yakaoma, elastic uye yakasimba. Inonyanya kuzivikanwa muchimiro chemavara akakora uye akatetepa muzvinhu zvakaita semasokisi, parachuti, uye bristles, naironi inoshandiswawo mukutengesa kwekuumba, kunyanya jekiseni kuumba.
Vanogona kugadzirirwa kubva ku dicarboxylic acid uye diamine kana amino acid iyo inogona kuzviisa-condensation, inoratidzwa ne "CONH" boka rinoshanda pamhete, senge ε-caprolactam. Nekusiyanisa asidhi uye amine, zvinokwanisika kugadzira zvigadzirwa serabha. Zvingave zvakagadzirwa sewaya kana muforoma, zvinoratidzwa nehupamhi hwekristaro. Pasi pekukakavadzana, kutaridzika kwemamorekuru kunoenderera kusvika sample yatambanudzwa kusvika kanenge kana kana kureba kwayo kwepakutanga, pfuma inonyanya kukosha mumafilaments.
bioplastic
Ipurasitiki uye zvinhu zvinogoneka zvinogadzirwa nemakemikari emakemikari anotorwa kana kugadzirwa nehutachiona senge mabhakitiriya kana zvidyarwa zvakagadziridzwa. Kusiyana nemhando dzakawanda dzatinotaura kana tichiisa mapurasitiki anogadzirwa kubva mupetroleum, bioplastics inogadzirwa kubva kune zvinogonekazve zviwanikwa, uye mamwe bioplastics anogona kugadzirwa. Kubva pakutanga kwezana remakore rechiXNUMX, kukura uye kushandiswa kwepurasitiki kwakawedzera uye kubatsira kwavo uye kukosha kwakakura zvakanyanya zvokuti zvakaoma kufungidzira hupenyu hwemazuva ano pasina ivo.
Nhasi, anenge ese mapurasitiki anowanikwa kubva mupetroleum kuburikidza nekugadzirwa kwemakemikari uye synthesis. Nekuda kwekuti mapurasitiki ane petroleum haawanzo kuparadzwa, tsvina yepurasitiki inogara kwenguva refu uye kuraswa kwayo kwave dambudziko rakakura. Pasinei nekuedza kukurudzira uye kutsigira kudzokororwa, marara anozadzwa nemarara epurasitiki, ayo anounganawo munharaunda.
Rimwe dambudziko remapurasitiki anotorwa nepetroleum nderekuti zviwanikwa zvinobva mupetroleum zviri kupera. Vanochengetedza zvinyorwa vanotenda kuti, pamwero wazvino wekushandiswa, zvese zvinozivikanwa manyuko emafuta paPasi zvichange zvapera pakupera kwezana ramakore rechiXNUMX. Sezvo hupenyu hwemazuva ano hunoenderana nemapurasitiki, oiri chinhu chisingadzokerikezve, uye tsvina yepurasitiki inotorwa nemafuta inosvibisa zvakatipoteredza, bioplastics inogona kuwana mhinduro yenguva refu.
Iyo yekutanga inozivikanwa bioplastic, polyhydroxybutyrate (PHB), yakawanikwa muna 1926 nemuongorori weFrance, Maurice Lemoigne, kubva kubasa rake pabhakitiriya Bacillus megaterium. Kukosha kwekuwanikwa kweLemoigne kwakafuratirwa kwemakumi emakore akawanda, zvakanyanya nekuti oiri yaive yakachipa uye yakawanda panguva iyoyo. Dambudziko reoiri repakati pema1970 rakanyandura kufarira kutsvaga dzimwe nzira dzezvigadzirwa zvepetroleum.
Kusimuka kwemamolecular genetics uye recombinant DNA tekinoroji mushure menguva iyi kwakakurudzira tsvagiridzo, zvekuti pakatanga XNUMXst century zvimiro, nzira dzekugadzira uye mashandisirwo emhando dzakawanda dzebioplastics dzave dzatangwa. Bioplastics yaishandiswa kana pasi pekudzidza yaisanganisira PHB uye polyhydroxyalkanoate (PHA), ese ari maviri akagadzirwa muhunyanzvi hutachiona, pamwe nepolylactic acid (PLA), iyo inogadzirwa kubva kulactic acid monomers inogadzirwa nemicrobial fermentation yeshuga inotorwa nechirimwa. starch.
Zvakare, zvinogona kutaurwa kuti kushatiswa kwemakemikari zvisungo pakati pe monomers mumapurasitiki aya kunokonzerwa ne microorganisms kana mvura, izvo zvinoita kuti bioplastics inodiwa zvikuru zvinhu zvekugadzira biodegradable mabhodhoro uye kurongedza mafirimu. Nekuda kwekuti zvigadzirwa zvekudzikisira ndezvemametabolites echisikigo, mapolymers anofarira kune zvekurapa zvikumbiro senge inodzorwa-inoburitsa zvinodhaka kurongedza uye inonwika yekuvhiya sutures.
Izvo zvinofanirwa kucherechedzwa kuti iyi kupatsanurwa kwemapurasitiki ikozvino inomiririra chikamu chidiki chepasi rose kugadzirwa kwemapurasitiki. Maitiro ekugadzira kutengeserana akabatana nekushomeka kwepasi uye kudhura kwakanyanya. Nekudaro, kuvandudzwa muinjiniya yemajini uye metabolism yakakonzera kuomarara kwehutachiona uye zvidyarwa zvinogona kuvandudza zvakanyanya goho uye kugona kugadzira uku ichidzikisa mutengo wese. Izvi zvinhu zvinogona kuwedzera musika webioplastics mune ramangwana.
PDK-Plastiki
Parizvino, ungangove wakanzwa nhamba yekuti chete 9% yemapurasitiki ndiwo anonyatso shandiswazve, uye mamwe achipera mumarara uye mumakungwa. Kuti varwise dambudziko repurasitiki, vanhu vazhinji vanoziva zvakatipoteredza vari kutama kubva kune zvinyorwa, asi boka revasayendisiti muBerkeley, California vari kuedza kuchinja zvinhu. Maererano neongororo, masayendisiti akagadzira chimiro chitsva chepurasitiki chinogonesa nzira yakavharwa yekudzokorora pasina tsvina.
Plastiki iyi inonzi polydiketoenamine kana PDK. Kazhinji, imhando yepurasitiki inobvumira kuti ishandiswe kubva kune molecular level, kupatsanura chimwe nechimwe chezvinhu uye kuzvibatanidza nazvo, kuitira kuti zviitike kakawanda uye nekudaro kuita kuti purasitiki ishande. . Hunhu hwayo hwakanyanya kufanana nedzimwe mhando dzepurasitiki senaironi uye nekudaro, inogona kushandiswa kugadzira midziyo yekuchengetera marudzi ese echikafu. Muchidimbu, mukwikwidzi akakwana kuve mukati mechikamu chepurasitiki.
SPI makodhi epurasitiki classification
Muna 1988, Sosaiti yeIndasitiri yePlastiki (SPI) yakagadzira hurongwa hwekuisa hurongwa hwekubatsira vanhu kudzokorodza nekurasa mapurasitiki nemazvo. Nhasi, vagadziri vanotevera iyi coding system uye vanoisa nhamba, kana SPI kodhi, pane chimwe nechimwe chigadzirwa, kazhinji pazasi. Purasitiki yakamaka ne SPI 1 kodhi inogadzirwa kubva ku polyethylene terephthalate. Midziyo iyi dzimwe nguva inotora hwema nekunakirwa kubva muzvokudya nezvinwiwa zvakachengetwa mukati. Nekudaro, iyi ichiri purasitiki yakajairika yezvinhu zvakawanda zvemumba uye zvekushandisa.
Iyo SPI kodhi ye2 inoratidza purasitiki yakagadzirwa kubva kune yakakwira-density polyethylene. Zvigadzirwa izvi zvakachengeteka zvakanyanya uye hapana humbowo hwemakemikari ari kupinda muchikafu kana zvinwiwa. Nekudaro, nekuda kwenjodzi yekusvibiswa, hazvina kuchengetedzeka kushandisazve bhodhoro reHDPE sechikafu kana chinwiwa mugaba kana pakutanga rakanga risina chero mhando yezvinhu zvinodyiwa. Semuenzaniso, hazvina kunaka kushandisa zvakare shampoo kana sipo midziyo kuchengetedza tomato muto.
Plastiki yakanyorwa neSPI kodhi ye3 inogadzirwa nepolyvinyl chloride. Mhando iyi yepurasitiki haifanirwe kusangana nechikafu, sezvo ikemikari ine chepfu uye ine ngozi. PVC inowanikwa mune zvakawanda zvemazuva ese zvinhu, asi inonyanya kuitirwa kushandiswa kwemaindasitiri mumapaipi epombi uye ekuvaka. Kune rumwe rutivi, iyo ine SPI code ye4 inogadzirwa ne-low-density polyethylene. Plastiki iyi inoita kunge yakasimba uye inochinjika. Izvo zvakare hazviburitse makemikari anokuvadza pane zvinhu, zvichiita kuti ive sarudzo yakachengeteka yekuchengetedza chikafu.
Iwe uchawana iyo SPI 5 kodhi pazvinhu zvepurasitiki zvakagadzirwa kubva ku polypropylene. Purasitiki yakanyorwa neSPI kodhi ye6 inogadzirwa kubva ku polystyrene, iyo inogona kudzokororwa, asi isingashande. Kugadzira patsva kunoda simba rakawanda, zvinoreva kuti nzvimbo shoma dzinozvigamuchira. Pakupedzisira, SPI code 7 inoshandiswa kuratidza marudzi akasiyana epurasitiki asina kutsanangurwa nemamwe makodhi matanhatu. Funga nezvemhando idzi semapurasitiki, asi hazvienderane nemitemo yevanhu.
Kana iwe wakafarira chinyorwa ichi pamhando uye kupatsanurwa kwepurasitiki uye uchida kudzidza zvakawanda nezve dzimwe nyaya dzinonakidza, unogona kutarisa zvinotevera zvinongedzo: