Moloko oa batho o sebelisitse lisebelisoa tsa tlhaho tsa polymeric tse kang lehong, letlalo le boea ho tloha tšimolohong ea histori, empa li-polymers tsa maiketsetso li ile tsa khoneha feela ka mor'a tsoelo-pele ea theknoloji ea rabara lilemong tsa bo-1800.Thepa ea pele ea Ž ea maiketsetso ea polymer, celluloid, e qapiloe ke John Wesley Hyatt ka 1869, ho tsoa ho cellulose nitrate le camphor.Katleho e kholo ho lipolima tsa maiketsetso e bile ho qaptjoa ha Bakelite ke Leo Hendrik Baekeland ka 1907. Mosebetsi oa Hermann Staudinger lilemong tsa bo-1920 o ile oa bontša ka ho hlaka sebōpeho sa macromolecular ea mahlaahlela a mangata a pheta-phetoang.1 Lentsoe 'polymer' le tsoa Segerikeng, 'me le bolela 'tse ngata likarolo'.Khōlo e potlakileng ea indasteri ea polymer e qalile nakoana pele ho Ntoa ea Bobeli ea Lefatše, ka nts'etsopele ea lipolymer tsa acrylic, polystyrene, nylon, polyurethanes le kenyelletso e latelang ea polyethylene, polyethylene terephthalate, polypropylene le polymers tse ling lilemong tsa bo-1940 le bo-1950.Le hoja ho ile ha hlahisoa lithane tse ka bang milione ka 1945, tlhahiso ea lipolasetiki ka bongata e ile ea feta ea tšepe ka 1981, 'me lekhalo le ntse le eketseha ho tloha ka nako eo.
Li-polymer tse hloekileng ha se hangata li sebetsoang ka botsona.Li kopanngoa le lisebelisoa tse ling, hangata ka ho kopanya mochine kapa ho qhibiliha ha boemo ba ho qhibiliha ho hlahisa li-pellets, li-powders kapa li-akas tse lokelang ho sebelisoa ts'ebetsong e latelang.Metsoako e ka kenyelletsa Ž llers (ho fokotsa litšenyehelo), li-reinforcement, li-polymers tse ling, li-colourants, li-retardants tsa ame, li-stabilizers (ho thibela ho senyeha ha leseli, mocheso kapa lintho tse ling tsa tikoloho) le lisebelisoa tse fapaneng tsa ho sebetsa.
Li-polymer tsa maiketsetso li ka aroloa ka mekhahlelo e 'meli.Thermoplastics (bolumo e kholo ka ho fetisisa) e ka qhibilihisoa ka ho futhumatsa, ho tiisa ka ho pholile le ho qhibiliha khafetsa.Mefuta e meholo ke polyethylene (PE), polypropylene(PP), polystyrene (PS), polyvinyl chloride (PVC), polycarbonate (PC), polymethyl methacrylate (PMMA), polyethylene terephthalate (PET) le polyamide (PA, nylon).Thermosets e thatafatsoa ke ts'ebeliso ea mocheso le khatello, ka lebaka la ho hokahana, ke hore, ho theha marang-rang a sa feleng a mahlakore a mararo.Li ke ke tsa nolofatsoa ka ho futhumatsa bakeng sa ho tsosolosoa.Bakelite, epoxies le polyurethanes tse ngata ke thermosets.
Tlhaloso ea hona joale e ikemiselitse feela ho sebetsa ha thermoplastics.Thermoplastics ea khoebo e hlophisitsoe ho latela ts'ebetso ea eona e le 'thepa' (ts'ebetso e tlase, joalo ka PE, PP, PS le PVC), 'Engineering' (joalo ka PC, nylon le PET) kapa 'e tsoetseng pele' (ts'ebetso e phahameng ka ho fetisisa, joalo ka metsi crystal polymers (LCPs), polyphenylene sulphide (PPS) le polyetheretherketone (PEEK)).Keketseho e phatlohileng e neng e lebelletsoe ho boenjiniere le li-polymer tse tsoetseng pele ha ea ka ea etsahala.Tšebeliso ea li-plastiki e ntse e hōla ka mokhoa o tsoelang pele lilemong tse mashome a mararo tse fetileng, empa haholo-holo sehlopheng sa thepa.Hajoale, lipolima tsa thepa li fihla ho ~ 88% ea molumo o hlahisoang, lipolasetiki tsa boenjiniere tse 3 ~ 12% mme li hatetse pele ka tlase ho 1%.Le hoja litheko tsa li-polymers tse tsoetseng pele ka kilogramme li phahame haholo ho feta tsa li-polymer tsa thepa, boleng ba tsona ba lefats'e moruong bo ntse bo le bonyenyane haholo.
Lipolasetiki tsa thepa li na le matla a tlase le ho satalla ha li bapisoa le litšepe kapa lirafshoa, 'me li na le ho bonts'a ho ts'oaroa ka tlas'a matla a sebelisitsoeng.Li boetse li na le meeli ea mocheso tšebelisong ea tsona e le lintho tse tiileng (tse ngata li qhibiliha ka har'a 100-250 ° C).The tensile moduli ea thepa ea polasetiki ~ 1 GPa (ha e bapisoa le 210 GPa bakeng sa tšepe).Ntlafatso ea Signi-Ž cant e ka finyelloa ka ho hokahanya liketane tsa polymer.Haele hantle, li-carbon-carbon bond li matla haholo, 'me polyethylene e le 'ngoe ea Ž lament e entsoe ka boleng ba modulus bo fetang ba tšepe.Boikutlo bo phahameng bo ka finyelloa ka mekhoa e khethehileng ea ho sebetsa, mohlala extrusion le setšoantšo se latelang ka mocheso o tlaase.Ka mocheso o tlase, liketane tsa polymer li na le motsamao o fokolang, 'me mokhoa o sala ka mor'a ho otlolla.Litšibollo tsa morao-rao le nts'etsopele ea sebaka se le seng, li-catalyst tse thehiloeng ho metallocene li entse hore ho be le limaraka tse ncha tsa li-polymer tsa thepa tse laolang meralo ea limolek'hule ka thepa e ntlafalitsoeng.
Tlhahiso ea lefats'e ea li-polymer e eketsehile3 ho tloha ho lithane tse limilione tse 27 ka 1975 ho ~ lithane tse limilione tse 200 ka selemo ka 2000 'me e ntse e hōla.Ho latela tlaleho ea morao-rao, thomello e 4 ea lihlahisoa tsa polasetiki USA ka 2000 e fihlile ho $ 330 bilione, 'me liindasteri tse fanang ka thepa e holimo li bile le thekiso ea lidolara tse limilione tse likete tse 90, e leng ho tlisa kakaretso ea selemo ho $420 bilione.Kakaretso ea mesebetsi e ne e hakanngoa hore e ka ba limilione tse 2 .4 - hoo e ka bang 2% ea basebetsi ba US.Khōlo ea indasteri ea polymer e bakoa ke motsoako o ikhethang oa thepa ea lihlahisoa tsa polasetiki, tse kenyelletsang ho bōptjoa ha bonolo le ho etsoa, li-densities tse tlaase, ho hanyetsa kutu, ho kenya motlakase le ho futhumatsa mocheso, 'me hangata ho thata le ho thatafala ka boima ba yuniti.
Nako ea poso: Feb-04-2018