Seo ho thoeng kepolyurethaneke khutsufatso ea polyurethane, e entsoeng ke karabelo ea polyisocyanate le polyols, 'me e na le lihlopha tse ngata tse pheta-phetoang tsa amino ester (- NH-CO-O -) ketane ea limolek'hule. Li-resin tsa polyurethane tse entsoeng ka 'nete, ntle le sehlopha sa amino ester, ho boetse ho na le lihlopha tse kang urea le biuret. Li-polyol ke tsa limolek'hule tse telele tse nang le lihlopha tsa hydroxyl qetellong, tse bitsoang "likarolo tse bonolo tsa ketane", ha li-polyisocyanate li bitsoa "likarolo tse thata tsa ketane".
Har'a li-resin tsa polyurethane tse hlahisoang ke likarolo tse bonolo le tse thata tsa ketane, ke karolo e nyane feela ea li-amino acid esters, kahoo ho ka 'na ha se ke ha e-ba ho loketseng ho li bitsa polyurethane. Ka kutloisiso e pharaletseng, polyurethane ke motsoako oa isocyanate.
Mefuta e fapaneng ea li-isocyanate e arabela le metsoako ea polyhydroxy ho hlahisa meaho e fapaneng ea polyurethane, ka hona e fumana thepa ea polymer e nang le thepa e fapaneng, joalo ka polasetiki, rabara, liphahlo, likhomaretsi, jj. Rabara ea polyurethane
Rabara ea polyurethane ke ea mofuta o khethehileng oa rabara, o etsoang ka ho kopanya polyether kapa polyester ka isocyanate. Ho na le mefuta e mengata ka lebaka la mefuta e fapaneng ea thepa e tala, maemo a karabelo, le mekhoa ea ho hokahanya. Ho ea ka pono ea sebopeho sa lik'hemik'hale, ho na le mefuta ea polyester le polyether, 'me ho ea ka pono ea mokhoa oa ts'ebetso, ho na le mefuta e meraro: mofuta oa ho kopanya, mofuta oa ho lahla, le mofuta oa thermoplastic.
Rabara ea polyurethane ea maiketsetso hangata e hlahisoa ka polyester e otlolohileng kapa polyether e nang le diisocyanate ho etsa prepolymer e boima bo tlase ba limolek'hule, e ntan'o kenngoa tšebetsong ea katoloso ea ketane ho hlahisa polymer e boima bo phahameng ba limolek'hule. Ebe, li-agent tse loketseng tsa ho hokahanya lia eketsoa le ho futhumatsoa ho e phekola, e fetoha rabara e qhibilihisitsoeng. Mokhoa ona o bitsoa prepolymerization kapa mokhoa oa mehato e 'meli.
Hape hoa khoneha ho sebelisa mokhoa oa mohato o le mong - ho kopanya ka ho toba polyester e otlolohileng kapa polyether le diisocyanate, liketane tse atolositsoeng, le metsoako e kopanyang ho qala karabelo le ho hlahisa rabara ea polyurethane.
Karolo ea A limolek'huleng tsa TPU e etsa hore liketane tsa macromolecular li be bonolo ho li potoloha, e fa rabara ea polyurethane ho tenyetseha ho hoholo, e fokotsa ntlha ea ho nolofatsa le ntlha ea phetoho ea bobeli ea polymer, 'me e fokotsa ho thatafala ha eona le matla a mechini. Karolo ea B e tla tlama ho potoloha ha liketane tsa macromolecular, e leng se etsang hore ntlha ea ho nolofatsa le ntlha ea phetoho ea bobeli ea polymer e eketsehe, e leng se fellang ka keketseho ea ho thatafala le matla a mechini, le ho fokotseha ha ho tenyetseha. Ka ho fetola karolelano ea molar pakeng tsa A le B, li-TPU tse nang le thepa e fapaneng ea mechini li ka hlahisoa. Sebopeho sa ho hokahanya sa TPU ha sea lokela ho nahana feela ka ho hokahanya ha mantlha, empa hape le ho hokahanya ha bobeli ho entsoeng ke litlamo tsa haedrojene pakeng tsa limolek'hule. Tlamo ea mantlha ea ho hokahanya ea polyurethane e fapane le sebopeho sa vulcanization sa rabara ea hydroxyl. Sehlopha sa eona sa amino ester, sehlopha sa biuret, sehlopha sa urea formate le lihlopha tse ling tse sebetsang li hlophisitsoe ka karolo e tsitsitseng ea ketane e tloaelehileng le e arohaneng, e leng se fellang ka sebopeho se tloaelehileng sa marang-rang sa rabara, se nang le khanyetso e ntle ea ho tsofala le thepa e meng e metle. Taba ea bobeli, ka lebaka la boteng ba lihlopha tse ngata tse sebetsang tse kopaneng haholo tse kang lihlopha tsa urea kapa carbamate ka har'a rabara ea polyurethane, litlamo tsa haedrojene tse entsoeng lipakeng tsa liketane tsa limolek'hule li na le matla a phahameng, 'me litlamo tsa bobeli tse kopanyang tse entsoeng ke litlamo tsa haedrojene le tsona li na le tšusumetso e kholo litšobotsing tsa rabara ea polyurethane. Ho kopanya ha bobeli ho nolofalletsa rabara ea polyurethane ho ba le litšobotsi tsa li-elastomer tsa thermosetting ka lehlakoreng le leng, 'me ka lehlakoreng le leng, ho hokahanya hona ha ho hlile ho amana, e leng se etsang hore e be ho hokahanya ho hoholo. Boemo ba ho hokahanya ho itšetlehile ka mocheso. Ha mocheso o ntse o eketseha, ho hokahanya hona hoa fokola butle-butle 'me hoa nyamela. Polymer e na le mokelikeli o itseng 'me e ka sebelisoa ka thermoplastic. Ha mocheso o fokotseha, ho kopanya hona hoa hlaphoheloa butle-butle 'me hoa hlaha hape. Ho eketsoa ha karolo e nyane ea filler ho eketsa sebaka se pakeng tsa limolek'hule, ho fokolisa bokhoni ba ho theha litlamo tsa haedrojene pakeng tsa limolek'hule, 'me ho lebisa phokotsong e kholo ea matla. Lipatlisiso li bontšitse hore tatellano ea botsitso ba lihlopha tse fapaneng tse sebetsang ka rabara ea polyurethane ho tloha holimo ho ea tlase ke: ester, ether, urea, carbamate, le biuret. Nakong ea ts'ebetso ea botsofali ba rabara ea polyurethane, mohato oa pele ke ho robeha ha litlamo tse hokahanyang pakeng tsa biuret le urea, ho lateloe ke ho robeha ha litlamo tsa carbamate le urea, ke hore, ketane e kholo e robehang.
01 Ho nolofatsa
Li-elastomer tsa polyurethane, joalo ka thepa e mengata ea polymer, lia nolofala mochesong o phahameng 'me li fetoha ho tloha boemong ba ho tenyetseha ho ea boemong ba phallo e hlabang, e leng se fellang ka phokotso e potlakileng ea matla a mechini. Ho ea ka pono ea lik'hemik'hale, mocheso o nolofatsang oa ho tenyetseha o itšetlehile haholo-holo ka lintlha tse kang sebopeho sa eona sa lik'hemik'hale, boima ba limolek'hule bo amanang, le bongata ba ho hokahanya.
Ka kakaretso, ho eketsa boima ba limolek'hule bo amanang, ho eketsa ho tiea ha karolo e thata (joalo ka ho kenya lesale la benzene ka har'a molek'hule) le litaba tsa karolo e thata, le ho eketsa bongata ba ho hokahanya kaofela ho molemo bakeng sa ho eketsa mocheso o nolofatsang. Bakeng sa li-elastomer tsa thermoplastic, sebopeho sa limolek'hule se batla se le mola, 'me mocheso o nolofatsang oa elastomer le oona oa eketseha ha boima ba limolek'hule bo eketseha.
Bakeng sa li-elastomer tsa polyurethane tse hokahaneng ka sefapano, bongata ba ho hokahanya ho na le tšusumetso e kholo ho feta boima ba limolek'hule. Ka hona, ha ho etsoa li-elastomer, ho eketsa ts'ebetso ea li-isocyanate kapa li-polyol ho ka theha sebopeho sa khokahano ea lik'hemik'hale tsa marang-rang se tsitsitseng mochesong ho tse ling tsa limolek'hule tse tenyetsehang, kapa ho sebelisa likarohano tse feteletseng tsa isocyanate ho theha sebopeho se tsitsitseng sa isocyanate se hokahaneng ka har'a 'mele o tenyetsehang ke mokhoa o matla oa ho ntlafatsa khanyetso ea mocheso, khanyetso ea solvent, le matla a mechini a elastomer.
Ha PPDI (p-phenyldisocyanate) e sebediswa e le thepa e tala, ka lebaka la kgokelo e tobileng ya dihlopha tse pedi tsa isocyanate le lesale la benzene, karolo e thata e bopilweng e na le lesale le phahameng la benzene, e leng se ntlafatsang ho tiya ha karolo e thata mme ka hona se eketsa ho hanyetsa mocheso wa elastomer.
Ho ya ka pono ya mmele, mocheso o nolofatsang wa di-elastomer o itshetlehile ka tekanyo ya karohano ya microphase. Ho ya ka ditlaleho, mocheso o nolofatsang wa di-elastomer tse sa feteng karohano ya microphase o tlase haholo, ka mocheso wa ts'ebetso wa hoo e ka bang 70 ℃ feela, ha di-elastomer tse fetang karohano ya microphase di ka fihla ho 130-150 ℃. Ka hona, ho eketsa tekanyo ya karohano ya microphase ho di-elastomer ke e nngwe ya mekgwa e sebetsang ya ho ntlafatsa ho hanyetsa ha tsona mocheso.
Tekanyo ea karohano ea microphase ea li-elastomer e ka ntlafatsoa ka ho fetola kabo ea boima ba limolek'hule ba likarolo tsa ketane le litaba tsa likarolo tsa ketane e tiileng, ka hona ho eketsa ho hanyetsa ha tsona mocheso. Bafuputsi ba bangata ba lumela hore lebaka la karohano ea microphase ka har'a polyurethane ke ho se lumellane ha thermodynamic pakeng tsa likarolo tse bonolo le tse thata. Mofuta oa extender ea ketane, karolo e thata le litaba tsa eona, mofuta oa karolo e bonolo, le ho tlamahana ha haeterojene kaofela li na le tšusumetso e kholo ho eona.
Ha ho bapisoa le di-extender tsa ketane ea diol, di-extender tsa ketane ea diamine tse kang MOCA (3,3-dichloro-4,4-diaminodiphenylmethane) le DCB (3,3-dichloro-biphenylenediamine) li theha lihlopha tse ngata tsa polar amino ester ho li-elastomer, 'me litlamo tse ngata tsa hydrogen li ka thehoa lipakeng tsa likarolo tse thata, e leng se eketsang tšebelisano lipakeng tsa likarolo tse thata le ho ntlafatsa tekanyo ea karohano ea microphase ho li-elastomer; Li-extender tsa ketane tse nang le monko o tšoanang tse kang p, p-dihydroquinone, le hydroquinone li molemo bakeng sa ho etsa hore likarolo tse thata li tloaelehe le ho pakoa ka thata, ka hona li ntlafatsa karohano ea microphase ea lihlahisoa.
Likarolo tsa amino ester tse entsoeng ke li-isocyanate tsa aliphatic li tsamaisana hantle le likarolo tse bonolo, e leng se fellang ka hore likarolo tse thata tse ngata li qhibilihe likarolong tse bonolo, e leng se fokotsang tekanyo ea karohano ea microphase. Likarolo tsa amino ester tse entsoeng ke li-isocyanate tse nkhang hamonate li tsamaisana hantle le likarolo tse bonolo, ha tekanyo ea karohano ea microphase e phahame. Polyolefin polyurethane e na le sebopeho se batlang se feletse sa karohano ea microphase ka lebaka la hore karolo e bonolo ha e thehe litlamo tsa haedrojene 'me litlamo tsa haedrojene li ka etsahala feela karolong e thata.
Tšusumetso ea ho tlamahana ha haedrojene ntlheng ea ho nolofatsa ha li-elastomer le eona e bohlokoa. Le hoja li-polyether le li-carbonyl karolong e bonolo li ka etsa palo e kholo ea litlamo tsa haedrojene le NH karolong e thata, e boetse e eketsa mocheso oa ho nolofatsa oa li-elastomer. Ho tiisitsoe hore litlamo tsa haedrojene li ntse li boloka 40% ho 200 ℃.
02 Ho bola ha mocheso
Lihlopha tsa Amino ester li senyeha ka tsela e latelang mochesong o phahameng:
- RNHCOOR – RNC0 HO-R
- RNHCOOR – RNH2 CO2 ene
- RNHCOOR – RNHR CO2 ene
Ho na le mefuta e meraro e meholo ea ho bola ha thepa e thehiloeng ho polyurethane ka mocheso:
① Ho theha li-isocyanate le li-polyol tsa mantlha;
② α— Tlamo ea oksijene motheong oa CH2 ea robeha 'me e kopana le tlamo e le 'ngoe ea haedrojene ho CH2 ea bobeli ho etsa li-amino acid le li-alkenes. Li-amino acid lia bola ho ba amine e le 'ngoe ea mantlha le carbon dioxide:
③ Sebopeho sa 1 sa amine ea bobeli le carbon dioxide.
Ho bola ha sebopeho sa carbamate ka mocheso:
Aryl NHCO Aryl, ~ 120 ℃;
N-alkyl-NHCO-aryl,~180 ℃;
Aryl NHCO n-alkyl,~200 ℃;
N-alkyl-NHCO-n-alkyl,~250 ℃.
Ho tsitsa ha mocheso oa li-ester tsa amino acid ho amana le mefuta ea lisebelisoa tsa ho qala tse kang li-isocyanate le li-polyol. Li-isocyanate tsa Aliphatic li phahame ho feta li-isocyanate tse nkhang hamonate, ha lino tse nang le mafura li phahame ho feta lino tse nkhang hamonate tse nkhang hamonate. Leha ho le joalo, lingoliloeng li tlaleha hore mocheso oa ho bola ha mocheso oa li-ester tsa aliphatic amino acid o pakeng tsa 160-180 ℃, 'me oa li-ester tsa amino acid tse nkhang hamonate o pakeng tsa 180-200 ℃, e leng se sa lumellaneng le lintlha tse ka holimo. Lebaka le ka 'na la amana le mokhoa oa teko.
Ha e le hantle, CHDI ea aliphatic (1,4-cyclohexane diisocyanate) le HDI (hexamethylene diisocyanate) li na le khanyetso e betere ea mocheso ho feta MDI le TDI tse sebelisoang hangata. Haholo-holo trans CHDI e nang le sebopeho se lekanang e 'nile ea tsejoa e le isocyanate e hanelang mocheso ka ho fetisisa. Li-elastomer tsa polyurethane tse entsoeng ho eona li na le bokhoni bo botle ba ho sebetsa, khanyetso e ntle ea hydrolysis, mocheso o phahameng oa ho nolofatsa, mocheso o tlase oa phetoho ea khalase, hysteresis e tlase ea mocheso, le khanyetso e phahameng ea UV.
Ntle le sehlopha sa amino ester, polyurethane elastomers le tsona li na le lihlopha tse ling tse sebetsang tse kang urea formate, biuret, urea, jj. Lihlopha tsena li ka senyeha ka mocheso mochesong o phahameng:
NHCONCOO – (formate ea urea ea aliphatic), 85-105 ℃;
- NHCONCOO – (mofuta o nkhang hamonate oa urea), mochesong oa 1-120 ℃;
- NHCONCONH – (aliphatic biuret), mochesong o tlohang ho 10 ° C ho isa ho 110 ° C;
NHCONCONH – (biuret e nkhang hamonate), 115-125 ℃;
NHCONH – (aliphatic urea), 140-180 ℃;
- NHCONH – (urea e nkhang hamonate), 160-200 ℃;
Lesale la Isocyanurate> 270 ℃.
Mocheso oa ho bola ha mocheso oa biuret le urea formate o tlase haholo ho feta oa aminoformate le urea, ha isocyanurate e na le botsitso bo botle ka ho fetisisa ba mocheso. Tlhahisong ea li-elastomer, li-isocyanate tse feteletseng li ka arabela haholoanyane le aminoformate le urea tse entsoeng ho theha meaho e hokahaneng ea urea le biuret. Le hoja li ka ntlafatsa litšobotsi tsa mechini tsa li-elastomer, ha li tsitse haholo ho futhumala.
Ho fokotsa lihlopha tse sa tsitsang tsa mocheso tse kang biuret le urea formate ho li-elastomer, ho hlokahala ho nahana ka karolelano ea tsona ea thepa e tala le mokhoa oa tlhahiso. Ho lokela ho sebelisoa likarolelano tse feteletseng tsa isocyanate, 'me mekhoa e meng e lokela ho sebelisoa ka hohle kamoo ho ka khonehang ho qala ka ho theha masale a isocyanate a sa fellang linthong tse tala (haholo-holo li-isocyanate, li-polyol, le li-extender tsa ketane), ebe li li kenya ka har'a elastomer ho latela lits'ebetso tse tloaelehileng. Ena e se e le mokhoa o sebelisoang haholo bakeng sa ho hlahisa li-elastomer tsa polyurethane tse hanelang mocheso le tse hanelang malakabe.
03 Hydrolysis le oxidation ea mocheso
Li-elastomer tsa polyurethane li sekametse ho bola ha mocheso likarolong tsa tsona tse thata le liphetoho tse tsamaellanang tsa lik'hemik'hale likarolong tsa tsona tse bonolo mochesong o phahameng. Li-elastomer tsa polyester li na le khanyetso e fokolang ea metsi le tšekamelo e matla ea ho hydrolyze mochesong o phahameng. Bophelo ba tšebeletso ea polyester/TDI/diamine bo ka fihla likhoeling tse 4-5 ho 50 ℃, libeke tse peli feela ho 70 ℃, le matsatsi a 'maloa feela ka holimo ho 100 ℃. Litlamo tsa Ester li ka bola ho ba li-acid le alcohols tse tsamaellanang ha li pepesetsoa metsi a chesang le mouoane, 'me lihlopha tsa urea le amino ester ho li-elastomer le tsona li ka feta liketsong tsa hydrolysis:
RCOOR H20- → RCOOH HOR
Joala ba ester
RNHCONHR e le 'ngoe H20- → RXHCOOH H2NR -
Ureamide
RNHCOOR-H20 e le 'ngoe- → RNCOOH HOR -
Amino formate ester Amino formate joala
Li-elastomer tse thehiloeng ho polyether li na le botsitso bo fokolang ba oxidation ea mocheso, 'me li-elastomer tse thehiloeng ho ether α- Haedrojene e holim'a athomo ea khabone e oxidation habonolo, e leng se etsang hydrogen peroxide. Kamora ho senyeha le ho arohana ho eketsehileng, e hlahisa li-radical tsa oxide le li-radical tsa hydroxyl, tse qetellang li bola ho ba li-formates kapa li-aldehydes.
Li-polyester tse fapaneng ha li na tšusumetso e kholo ho haneleng mocheso oa li-elastomer, ha li-polyether tse fapaneng li na le tšusumetso e itseng. Ha li bapisoa le TDI-MOCA-PTMEG, TDI-MOCA-PTMEG e na le sekhahla sa ho boloka matla a ho hula sa 44% le 60% ka ho latellana ha e tsofala ka 121 ℃ matsatsi a 7, 'me ea morao e betere haholo ho feta ea pele. Lebaka e ka ba hore limolek'hule tsa PPG li na le liketane tse nang le makala, tse sa lumellaneng le tokisetso e tloaelehileng ea limolek'hule tse tenyetsehang le ho fokotsa ho hanyetsa mocheso oa 'mele o tenyetsehang. Taelo ea botsitso ba mocheso ea li-polyether ke: PTMEG>PEG>PPG.
Lihlopha tse ling tse sebetsang ka har'a li-elastomer tsa polyurethane, tse kang urea le carbamate, le tsona li feta liketsong tsa oxidation le hydrolysis. Leha ho le joalo, sehlopha sa ether ke sona se oxidation habonolo, ha sehlopha sa ester se le sona se hanyetswang habonolo. Tatellano ea khanyetso ea tsona ea antioxidant le hydrolysis ke:
Mosebetsi oa antioxidant: esters>urea>carbamate>ether;
Khanyetso ea hydrolysis: ester
Ho ntlafatsa khanyetso ea oxidation ea polyether polyurethane le khanyetso ea hydrolysis ea polyester polyurethane, ho boetse ho eketsoa li-additives, tse kang ho eketsa 1% phenolic antioxidant Irganox1010 ho PTMEG polyether elastomer. Matla a ho tensile a elastomer ena a ka eketsoa ka makhetlo a 3-5 ha a bapisoa le ntle le li-antioxidants (liphetho tsa liteko kamora ho tsofala ho 1500C ka lihora tse 168). Empa ha se antioxidant e 'ngoe le e 'ngoe e nang le phello ho polyurethane elastomers, ke phenolic 1rganox 1010 le TopanOl051 feela (phenolic antioxidant, hindraised amine light stabilizer, benzotriazole complex) tse nang le litlamorao tse kholo, 'me ea pele ke eona e ntle ka ho fetisisa, mohlomong hobane li-antioxidants tsa phenolic li tsamaisana hantle le li-elastomer. Leha ho le jwalo, ka lebaka la karolo ya bohlokwa ya dihlopha tsa phenolic hydroxyl mokgweng wa ho tsitsisa di-antioxidants tsa phenolic, e le ho qoba karabelo le "ho hloleha" ha sehlopha sena sa phenolic hydroxyl ka dihlopha tsa isocyanate tsamaisong, karolelano ya di-isocyanate ho di-polyol ha ya lokela ho ba kgolo haholo, mme di-antioxidants di lokela ho eketswa ho di-prepolymer le di-extender tsa ketane. Haeba e eketswa nakong ya tlhahiso ya di-prepolymer, e tla ama haholo phello ya ho tsitsisa.
Li-additi tse sebelisoang ho thibela hydrolysis ea polyester polyurethane elastomers ke metsoako ea carbodiimide haholo-holo, e arabelang le li-carboxylic acid tse hlahisoang ke ester hydrolysis ka har'a limolek'hule tsa polyurethane elastomer ho hlahisa li-derivatives tsa acyl urea, e leng se thibelang hydrolysis e eketsehileng. Ho eketsoa ha carbodiimide ka karolo e kholo ea 2% ho isa ho 5% ho ka eketsa botsitso ba metsi ba polyurethane ka makhetlo a 2-4. Ho phaella moo, tert butyl catechol, hexamethylenetetramine, azodicarbonamide, jj. le tsona li na le litlamorao tse itseng tsa anti hydrolysis.
04 Litšobotsi tsa mantlha tsa ts'ebetso
Li-elastomer tsa polyurethane ke li-copolymer tse tloaelehileng tsa li-block tse ngata, tse nang le liketane tsa limolek'hule tse entsoeng ka likarolo tse tenyetsehang tse nang le mocheso oa phetoho ea khalase o tlase ho mocheso oa kamore le likarolo tse tiileng tse nang le mocheso oa phetoho ea khalase o phahameng ho feta mocheso oa kamore. Har'a tsona, li-polyol tsa oligomeric li etsa likarolo tse tenyetsehang, ha li-diisocyanate le li-extender tsa ketane ea limolek'hule tse nyane li etsa likarolo tse tiileng. Sebopeho se kenelletsoeng sa likarolo tsa ketane tse tenyetsehang le tse tiileng se etsa qeto ea ts'ebetso ea tsona e ikhethang:
(1) Mefuta e thata ea rabara e tloaelehileng hangata e pakeng tsa Shaoer A20-A90, ha mefuta e thata ea polasetiki e ka ba Shaoer A95 Shaoer D100. Li-elastomer tsa polyurethane li ka fihla tlase ho Shaoer A10 le holimo ho Shaoer D85, ntle le tlhoko ea thuso ea ho tlatsa;
(2) Matla a phahameng le ho tenyetseha ho ntse ho ka bolokoa ka har'a mefuta e mengata ea thatafalo;
(3) Ho hanyetsa ho tsofala ho hoholo, ka makhetlo a 2-10 ho feta rabara ea tlhaho;
(4) Ho hanyetsa metsi, oli le lik'hemik'hale hantle haholo;
(5) Ho hanyetsa tšusumetso e phahameng, ho hanyetsa mokhathala, le ho hanyetsa ho thothomela, ho loketse lits'ebetso tsa ho kobeha khafetsa;
(6) Ho hanyetsa mocheso o tlase hantle, ka ho robeha ha mocheso o tlase ka tlase ho -30 ℃ kapa -70 ℃;
(7) E na le ts'ebetso e ntle ea ho thibela ho ruruha, 'me ka lebaka la ho khanna ha eona mocheso o tlase, e na le phello e betere ea ho thibela ho ruruha ha ho bapisoa le rabara le polasetiki;
(8) Ho ikamahanya hantle le lintho tse phelang le thepa ea ho thibela ho ruruha ha mali;
(9) Ho thibela mocheso o motle oa motlakase, ho hanyetsa hlobo le botsitso ba UV.
Li-elastomer tsa polyurethane li ka etsoa ka mekhoa e tšoanang le ea rabara e tloaelehileng, joalo ka ho etsa polasetiki, ho kopanya le ho etsa vulcanization. Li ka boela tsa bōptjoa ka mokhoa oa rabara ea metsi ka ho tšela, ho etsa centrifugal, kapa ho fafatsa. Li ka boela tsa etsoa ka thepa ea granular 'me tsa etsoa ka ho sebelisa ente, extrusion, rolling, blow molding, le mekhoa e meng. Ka tsela ena, ha e ntlafatse feela katleho ea mosebetsi, empa e boetse e ntlafatsa ho nepahala ha boholo le ponahalo ea sehlahisoa.
Nako ea poso: Tshitwe-05-2023