Ityuwa ye-nylon 66, ebizwa ngokuba yi-hexamethylenediammonium adipate, yimveliso echanekileyo ye-hexamethylenediamine (HMDA) kunye ne-adipic acid. Yinto yokuqala ye-nylon 66 polymer, elawula iiplastiki zobunjineli ngenxa yamandla ayo aphezulu oomatshini kunye nokuzinza kobushushu. Le tyuwa, efunyenwe njenge-crystalline ionic compound kwisisombululo samanzi, ibonisa iipropati ezikhethekileyo ezibalulekileyo kwinkqubo ye-polycondensation esezantsi evelisa imicu ye-nylon 66 kunye ne-resins. Ulwakhiwo lwe-molecular lune-ammonium etshajiweyo kakuhle evela kwi-HMDA kunye namaqela e-carboxylate etshajiweyo kakubi evela kwi-adipic acid, okwenza ii-ionic lattices okanye, xa zinyibilikisiwe, ii-ions ezizimeleyo ezilungele ukwenziwa i-polymerization.
Ukulungelelana kunye nobunyulu besakhiwo buchaphazela ngokuthe ngqo ubunzima bemolekyuli yepolymer, ubukristali, kunye neprofayili yobushushu. Izifundo zelebhu kunye nezemizi-mveliso ziqinisekisa umlinganiselo oqinileyo we-1:1 ionic usebenzisa iindlela ze-spectroscopic kunye ne-X-ray diffraction, nto leyo eyenza ukuba le stoichiometry ibe yinto ebalulekileyo ekusebenzeni kakuhle kwemveliso yokugqibela. Nokuba ukuphambuka okuncinci kunokuphazamisa ukufana kweetyathanga, okukhokelela kwiipropati eziphantsi zoomatshini.
Ukulungiswa kweTyuwa yeNylon 66
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I-Hexamethylenediamine, enesakhiwo sayo esithe ngqo se-H2N-(CH2)6-NH2, isebenza njengecandelo le-diamine elinika amaqela e-terminal amine ukuze kwenziwe ityuwa. I-Adipic acid, i-HOOC-(CH2)4-COOH, incedisa oku ngemisebenzi ye-reactive carboxyl. Ukunyaniseka kwayo ekusebenzeni kunye nobunyulu obuphezulu bubaluleke kakhulu: I-HMDA idla ngokunyibilikiswa okanye i-crystallized ukuze kususwe imikhondo ye-oligomeric kunye neye-organic, ngelixa i-adipic acid iphinda iguqulwe, ihluzwe, kwaye ngamanye amaxesha itshintshiselwano lwe-ion ukuqinisekisa ukususwa kwezinto ezinombala, izinto eziphilayo, kunye nezinto ezingcolisayo zesinyithi. Ubunyulu obungaphezulu kwe-99.5% bujoliswe kwimizi-mveliso; nokuba izinto ezingcolisayo zingonakalisa umgangatho we-polymer, zitshintshe umbala wezinto ezigqityiweyo, okanye zibangele ityhefu kwiimpendulo ezilandelayo.
Isiseko sokwenziwa kwetyuwa ye-nylon 66 sisisombululo esilula kodwa esilawulwa ngokuqinileyo sokungashukumi. Kwisisombululo samanzi, i-HMDA yamkela iiprotoni ezivela kumaqela e-carboxyl e-adipic acid, zenze ii-ion ze-ammonium ngelixa ngaxeshanye zivelisa ii-carboxylates. Olu nxibelelwano lwe-acid-base lucwangciswe ngononophelo:
I-H2N-(CH2)6-NH2 + I-HOOC-(CH2)4-COOH → [H2N-(CH2)6-NH3+][OOC-(CH2)4-COO−] (ityuwa yenayiloni, emanzi)
Ngokwendlela yokusebenza, ukudibana kokuqala kuvumela i-diamine ukuba iprotenate kancinci, yenze i-zwitterionic intermediate. Ukugqitywa kuxhomekeke ekudlulisweni kwe-proton epheleleyo kunye nokungaguquguquki. I-pH yenzelwe ukufikelela kwi-neutral—kufutshane ne-7—njengophawu lwe-acid-base equivalents elinganayo. Ubushushu obufanelekileyo buphucula zombini i-reaction kinetics kunye ne-salt crystallization elandelayo; ekusebenzeni, amaqondo obushushu ukusuka kwi-25°C ukuya kwi-100°C asetyenziswa. Nangona kunjalo, ukugqithisela kwi-pH okanye amaqondo obushushu kunokucothisa ukusabela okanye ukuvelisa iimveliso eziphumayo: iimeko ezine-asidi kakhulu okanye ezisisiseko zikhuthaza ukwakheka kwetyuwa engaphelelanga kwaye zinokutshintsha ukunyibilika kunye nemo yekristale. Ukuqinisekiswa komgangatho wanamhlanje kusebenzisa imilinganiselo ye-pH emgceni kunye nokulinganisa i-conductivity, ehlala ijongwa rhoqo, ukuqinisekisa i-stoichiometry echanekileyo kunye nokuthintela ukuphazamiseka kwenkqubo.
Ukugqithisa okanye ukunqongophala kwi-reactant kujika amaqela okuphela komsebenzi kwityuwa, kwaye, ngokwandisa, kwi-polymer ye-nylon. Oku kuchaphazela ubude betsheyini, ukusasazeka kwe-poly, kunye neempawu zokuxinana. Ubudlelwane phakathi koxinano lwesisombululo setyuwa kunye nolawulo lwenkqubo bugxininiswa kwimisebenzi yemizi-mveliso yanamhlanje, aphoumlinganiselo woxinano lolwelo ngexesha langempelakunye nokulinganiswa okungqongqo kwemitha yoxinano lolwelo kubalulekile kwinkqubo yokulungiselela ityuwa ye-nylon 66. Ukubeka iliso ngokufanelekileyo koxinano akuqinisekisi nje kuphela ukufana kwebhetshi ukuya kwibhetshi kodwa kukwanceda ukulawula izisombululo zetyuwa eyosiweyo kunye ne-supersaturated ezifunekayo kwi-polymerization okanye yokugcina elandelayo.
Ngokufutshane, ukusebenzisana okulungelelanisiweyo phakathi kwekhemistri yokungaguquguquki, ulawulo lwe-pH kunye nobushushu, kunye nobunyulu obumangalisayo be-HMDA kunye ne-adipic acid kusekela inkqubo ephumelelayo yokwenziwa kwetyuwa ye-nylon 66. Yile ndlela ichanekileyo elawula umgangatho wendlela yonke yokuveliswa kwe-nylon 66 polymer kwaye, ekugqibeleni, ukusetyenziswa kwezinto zoshishino kwiimoto, ilaphu, kunye nemigca yemveliso yombane.
Inkqubo yoLungiso lweTyuwa yeNylon 66 Inyathelo ngeNyathelo
Inkqubo yokulungiselela ityuwa ye-nylon 66 iqala ngokulungiselela izisombululo zamanzi ezahlukeneyo ze-adipic acid kunye ne-hexamethylenediamine, ii-monomers ezimbini eziphambili ezibalulekileyo ekuvelisweni kwetyuwa ye-nylon 66. I-Adipic acid iyanyibilika emanzini angena-ion, ngesiqhelo kwi-30-60°C, de kube kuvela isisombululo esicacileyo. I-Hexamethylenediamine idlula kwinkqubo efanayo, ivelisa isisombululo esityebileyo se-amine. Zombini izisombululo zihluzwa ngononophelo ukuze kususwe ii-particles ngaphambi kokuba kuphinde kuvele impendulo, zixhasa ukulinganiswa koxinano lwesisombululo setyuwa ukuze kulawulwe umlinganiselo ochanekileyo kunye nokuhamba kakuhle kwenkqubo.
Ukuxuba okulawulwayo nokulawulwa kobushushu kubalulekile ekufezekiseni umlinganiselo we-stoichiometric 1:1 molar, njengoko nokuba ukuphambuka okuncinci kuchaphazela kakubi ukusebenza kakuhle kwe-polymerization kunye neempawu ze-resin. Ezi zisombululo zimbini zingeniswa kancinci kancinci—ngokufuthi ngokuhla—kwi-reactor enejakethi exhotyiswe ngokushukumisa okusebenzayo, okuvumela ulawulo olucokisekileyo lwamazinga okuxuba. Ubushushu obulawulwa ngokuchanekileyo buthintela ubushushu obuphezulu bendawo, i-crystallization yangaphambi kwexesha, okanye i-hydrolysis engafunekiyo, okuqinisekisa indawo efanayo yempendulo yetyuwa ye-nylon 66.
Kuyo yonke intshukumo yokuxuba kunye nokungaguquguquki kwimveliso ye-nylon 66, ingubo yegesi engasebenziyo, edla ngokuba yi-nitrogen, igcinwa kwisitya. Olu khuseleko lomoya ongasebenziyo lubalulekile ekuthinteleni ioksijini yomoya kunye ne-carbon dioxide, enokubangela i-oxidation okanye ingenise ukungcola kwe-carbonate/bicarbonate, oko kunciphisa umgangatho wetyuwa. Igesi engasebenziyo ikwaphucula ukuhambelana kwemveliso kunye nozinzo lokugcina, okubalulekileyo kwizicelo eziphezulu.
Njengoko ukuxubana okulawulwayo kuqhubeka, iintlobo eziphakathi ezine-carboxyl okanye i-amine terminals zinokwenzakala, kuxhomekeke kwi-stoichiometry yendawo kunye nesantya sokuxuba. Ukungaguquguquki okupheleleyo kuvelisa ityuwa ye-nylon 66 efunekayo (ekwaziwa ngokuba yi-AH salt), ene-stoichiometry echazwe kakuhle kunye nokufana kweemolekyuli. I-reaction ye-neutralization ilandela imigaqo ye-acid-base chemistry, kwaye ukufikelela kwi-pH echanekileyo kufutshane ne-neutral (pH 7–7.3) kuyimfuneko kwi-polymerization ehambelanayo, kuba amaqela e-acid okanye e-base agqithisileyo aphazamisa ukukhula kwe-chain kwaye achaphazela ubunzima kunye nomgangatho weemolekyuli zepolymer yokugqibela.
Ukubeka iliso kwi-pH kunye ne-real time titration kuvumela impendulo eqinileyo ngexeshaukuthambekisa, ukuqinisekisa ukuba ulandelelwano lokuxuba kunye namazinga aphuculweyo ukuze kuthintelwe ukunganyamezeli okanye ukunganyamezeli kakuhle kwendawo. Iimodeli ze-kinetic zanamhlanje ziqinisekisa ukuba nokuba ukungalingani okuncinci kwi-stoichiometry kuyayithintela ngokuyilinganiselayo indlela esebenza ngayo i-polymerization.
Emva kokwenziwa kwetyuwa engathathi hlangothi, le nkqubo iqhubekela phambili ngamanqanaba okucoca ukuqinisekisa imveliso ecocekileyo kakhulu. Amaqhinga okucoca amanqanaba amaninzi—aqhubekela phambili ukusuka kwi-coarse ukuya kwi-submicron filter media—asusa ii-ion zesinyithi, ii-particles, kunye nee-organic residues eziveliswa zizinto eziluhlaza okanye amanzi okucubungula. Unyango lokutshintshiselana ngee-ion lulandela, lukhupha ukungcola okunganyibilikiyo okufana ne-sulfate, i-calcium, okanye ii-ion ze-sodium eziyingozi kumgangatho wetyuwa ye-nylon. Emva koko umxube uxutywe kwaye uphantsi kwe-crystallization elawulwayo, uvelisa iikristale zetyuwa ezicociweyo ngokucaca kokukhanya kunye namanqanaba angabonakaliyo ombala okanye i-haze.
Ulawulo lomgangatho ludibene ngokuqinileyo neendlela zokulungiselela ityuwa ezisetyenziselwa imboni, kunye nokubeka esweni rhoqo ukufunxwa kwe-UV kunye nobumsulwa bokukhanya kwinqanaba ngalinye. Isalathisi esiphantsi se-UV sibalulekile—isalathisi esiphezulu sibonisa ubukho bokungcola kwe-chromophoric, okunokutshintsha umbala kwiimveliso ze-polymer ze-nylon 66 kwaye kukhokelele kwiziphene kwiifayibha okanye kwiindawo ezibunjiweyo. Kwiinkqubo ze-polymerization ezixabisa kakhulu, ukujonga okubonakalayo kunye ne-spectroscopic kuqinisekisa ityuwa engenambala, ecocekileyo ngokokukhanya, ukuthintela ukutyheli kunye nokungahambelani koomatshini.
Ukubeka iliso kuxinano kwiinkqubo zeekhemikhali, ngakumbi kusetyenziswa iindlela zokulinganisa uxinano lolwelo kunye neemitha zoxinano ezikwimigca efana nezo zenziwe yiLonnmeter, zongeza ukhuseleko olongezelelweyo. Ezi zixhobo ziqinisekisa uxinano lokugqibela lwesicombululo setyuwa, zixhasa ukuphindaphinda kwenkqubo. Ukulinganiswa kwemitha yoxinano lolwelo ngokuchanekileyo kubalulekile ekufumaneni ukuphambuka okuncinci kumxholo wezinto eziqinileyo, okuchaphazela ngokuthe ngqo ukwenziwa kwekristale kunye namanyathelo alandelayo okwenziwa kwepolymer.
Ukuhlanganiswa kokucoca okungqongqo kunye nolawulo lomgangatho kwinkqubo yokulungiselela ityuwa ye-nylon 66 kuxhasa zombini isivuno kunye nokusebenza kwe-polymer. Ukujonga ngokubanzi uhlalutyo, ukusuka kwi-UV index ukuya kwi-pH kunye noxinano, kwenza kube lula ukwenziwa rhoqo kwetyuwa ecocekileyo kakhulu, ecacileyo, kunye ne-stoichiometrically balanced efanelekileyo kwizicelo ze-polymer zoshishino ezifuna imali eninzi.
Imveliso yeTyuwa yeNylon 66 yoShishino: Ukwandisa kunye nokuphucula iinkqubo
Ukwenziwa Kwetyuwa Kwizinga Loshishino
Inkqubo yokulungiselela ityuwa ye-nylon 66 yemizi-mveliso igxile kwimpendulo yokungaguquguquki phakathi kwe-adipic acid kunye ne-hexamethylenediamine. Ukunyuka ukusuka kwilebhu ukuya kwimisebenzi yesityalo kubandakanya ukuguqula ukungaguquguquki kwe-batchwise kube yinkqubo eqhubekayo, apho ii-reactants zidibana phantsi kweemeko ezilawulwa ngononophelo ukuvelisa i-hexamethylenediammonium adipate—ekwabizwa ngokuba yityuwa ye-nylon.
Kwimveliso enkulu yetyuwa ye-nylon 66, umgangatho ohambelanayo wezinto ezikrwada ubalulekile. Ukuguquguquka kwe-adipic acid okanye i-hexamethylenediamine ubumsulwa kuchaphazela ngokuthe ngqo i-stoichiometry, okubangela imveliso engaqhelekanga ukuba ayilawulwa. Iinkqubo zokutya kufuneka zivumele ukudoswa okuzinzileyo, okuhlawulela ukuguquguquka okuphezulu kokunikezelwa kwezinto ezikrwada kunye nobushushu.
Ukuxuba okufanayo yenye imbombo. Ii-reactors zoshishino zixhomekeke kwi-high-intensity agitation ukuze ziphephe i-concentration gradients ekhokelela ekungaphelelini ngokupheleleyo. Ukuxuba okubi kubangela iipokotho ze-asidi okanye i-amine engaphendulwanga, nto leyo edala iityuwa ezine-pH engaguqukiyo kunye neendawo zokunyibilika eziguquguqukayo. Izityalo zanamhlanje zisebenzisa ii-continuous stirified-tank reactors (CSTRs) ukuze zixube kakuhle kwaye zivelise imveliso efanayo, ingakumbi xa zijongene nemijelo yezinto eziluhlaza ezitshintshatshintshayo okanye xa kufuneka i-stoichiometry echanekileyo. Kwi-chemistry elula kwaye apho kukhethwa khona ukuhamba okuthe ngqo, ii-plug flow reactors (PFRs) zibonelela ngokusasazwa kwexesha lokuhlala okuqinileyo kunye nokuphakama kobushushu bendawo okuphantsi, kodwa azinazo zonke izakhono zokuxuba ze-CSTRs.
Ulawulo lobushushu luxhasa uzinzo lwenkqubo. Ukunganyamezeli kwe-exothermic kufuna izitya ezinejakethi okanye ii-heat exchangers ukuze kugcinwe ubushushu obufanelekileyo—ngokuqhelekileyo kufutshane nama-210°C. Ukuguquguquka okungaphezulu okanye ngaphantsi kweli nqanaba kubangela i-hydrolysis okanye i-crystallization embi yetyuwa, ngokulandelelana, okuthintela i-polymerization esezantsi.
Imigca yeeMveliso zoShishino kunye nezixhobo
Izixhobo ezinkulu ze-nylon 66 salt reaction zibonakaliswa kukwakhiwa kwazo okuqinileyo kunye nokuhlanganiswa kweteknoloji zolawulo oluchanekileyo. Ukukhethwa kwee-reactor ikakhulu kuphakathi kwee-CSTR, ezithandwa ngenxa yokushukuma kwazo okusebenzayo kunye nokulingana kwe-composition, kunye nee-PFR, ezenza kube lula ukuhamba okuqhubekayo kwe-high-throughput apho ukuxuba okufanayo kungabaluleke kakhulu.
Iinkqubo zokuxuba zemizi-mveliso zenzelwe ukuxuba ngokukhawuleza nangokupheleleyo imijelo ye-asidi kunye ne-diamine. Ii-impellers ezishefa kakhulu kunye nee-recirculation loops zisasaza ii-reactants ngokulinganayo nangona kukho utshintsho olukhulu okanye i-viscosity, nto leyo enciphisa umngcipheko weendawo ezishushu kunye nokungapheleli komoya.
Iinkqubo zokubeka esweni inkqubo ezikwi-intanethi zibalulekile ukulawula nokubhala phantsi inqanaba ngalinye. Ii-inline pH probes, ii-temperature sensors, kunye nee-inline density meters eziphambili (ezifana nezo zenziwe yiLonnmeter) zibalulekile kwiindlela zanamhlanje zokufakela. Ukulinganiswa koxinano lolwelo ngexesha langempela kwenza abaqhubi baqinisekise uxinano oluchanekileyo lwetyuwa kunye nokwakheka kwayo kuyo yonke inkqubo. Ezi zisombululo zokubeka esweni uxinano zibonelela ngempendulo evumela ukulungiswa kwangethuba kwamazinga okutya kunye nobushushu ukuze kugcinwe umgangatho wetyuwa ohambelanayo. Ukulinganiswa kwemitha yoxinano lolwelo rhoqo kwenziwa kusetyenziswa izisombululo zetyuwa ezichazwe kakuhle ukuqinisekisa ukuchaneka kwedatha phantsi kweemeko zemveliso ezitshintshayo.
Iindlela zokuphatha ngokukhuselekileyo ziyimfuneko ngenxa yokuba izisombululo zetyuwa ye-nylon 66 ziyabola kwaye zinoburhabaxa. Iitanki zokugcina zakhiwe ngee-alloys ezimelana nokubola, ezineenkqubo zokugquma ezithintela ukufunxwa komswakama kunye nongcoliseko. Imibhobho yokuthutha evaliweyo, iinkqubo zokulayisha ezenzekelayo, kunye neempawu zokuthintela ukuchitheka kwazo zonke zinegalelo ekunciphiseni iingozi zokusingqongileyo kunye nabasebenzi ekugcinweni nasekudlulisweni kwesisombululo setyuwa.
Ukulungiswa kweNkqubo ukuze kube nokuHlangana kweMveliso
Ukugcina imveliso ihambelana kakuhle kwimveliso yetyuwa ye-nylon 66 kufuna ukulungiswa ngokuchanekileyo kweeparamitha zenkqubo. I-target viscosity—uphawu olubalulekileyo kwiimpawu zokugqibela ze-nylon 66 polymer—ixhomekeke kulawulo oluqinileyo lweemeko zokusabela ngexesha lokwenziwa kwetyuwa kunye ne-polymerization yayo elandelayo.
Ubushushu bugcinwa bumalunga nama-210°C xa kukho ukunyamezelana okuqinileyo, njengoko ukuphambuka kutshintsha inqanaba lokungashukumi kunye nokunyibilika kwetyuwa. Ulawulo loxinzelelo, oluhlala lubekwe kufutshane ne-1.8 MPa kumanyathelo angaphambi kokuphola, luqinisekisa ukuziphatha kwesigaba esichanekileyo kunye ne-kinetics yokusabela. Ixesha lokuhlala kwii-reactors liyalinganiswa ukuvumela ukuguqulwa okupheleleyo, ngelixa kuthintelwa ukuvezwa okugqithisileyo kobushushu okunokonakalisa imveliso. Esi senzo sokulinganisela siphuculwa ngakumbi kusetyenziswa idatha evela kwiimitha ze-viscosity kunye ne-density.
Ukukhethwa kweCatalyst kunye nomthamo kunefuthe elibonakalayo kwisigaba se-polymerization se-nylon 66, esilandela ukwakheka kwetyuwa. Iidosi ze-catalyst eziqhelekileyo zimalunga ne-0.1 wt% ukuze kuphuculwe ubunzima be-molecular kunye nokukhuthaza ukukhula kwe-polymer chain esebenzayo. Ukugqithisa umthamo kunokukhawulezisa impendulo kodwa kubeka emngciphekweni ukwakheka kwamasebe okungalawulwayo okanye umbala; ukungalingani komthamo kuphazamisa ukwenziwa kwe-polymer kunye neempawu zoomatshini. Ukulinganisa ngokufanelekileyo kunye nokuxuba ngokukhawuleza kwe-catalyst, rhoqo kwisisombululo kunye nokutya kwetyuwa, kuphucula ukusebenza kakuhle ngokubanzi.
Nganye kwezi parameters ilungiswa ngokuguquguqukayo ngexesha langempela ngokusekelwe kwidatha yomgangatho. Umzekelo, ukuba ukujonga uxinano olungaphakathi kubonisa ukuphambuka okubonisa ukugqithisileyo okanye ukunganeli kwe-neutralization, amazinga okutya kwe-reactant ayaguqulwa ngokufanelekileyo. Olu tshintsho lwempendulo lubalulekile ekuthinteleni ityuwa engalinganiyo, eya kuthi kamva ibeke emngciphekweni i-polymer viscosity kunye nokusebenza kokugqibela.
Ubuninzi beSombululo seTyuwa: Amaqhinga okuJonga nokuLinganisa
Ukubaluleka Kokujongwa Koxinano Ekulungiseni Ityuwa
Ngexesha lenkqubo yokulungiselela ityuwa ye-nylon 66, ukujonga uxinano kubalulekile. Impendulo ye-stoichiometric phakathi kwe-hexamethylenediamine kunye ne-adipic acid ivelisa ityuwa ecocekileyo kwaye ifanelekile kwinkqubo yokuvelisa i-nylon 66 polymer ibonakaliswa ngokuthe ngqo buxinano lwesisombululo. Ukulinganiswa koxinano oluchanekileyo kubonisa uxinano lwe-reactant, kuqaqambisa ibhalansi phakathi kwe-asidi kunye ne-amine, kwaye kusebenza njengommeli wokugqitywa kokuguqulwa kunye nomxholo wamanzi.
Ukugcina uxinano olufanelekileyo lwesisombululo setyuwa kubalulekile. Ukuphambuka okuncinci kunokuveza i-off-stoichiometry, efana ne-asidi egqithisileyo okanye i-amine, ephazamisa ukusebenza kakuhle kwe-polymerization, ichaphazela ukusasazwa kobunzima be-molecular, kwaye ikhokelele kwiipropati zokugqibela eziphantsi. Umzekelo, ekusetyenzisweni kwakhona kweekhemikhali, utshintsho kuxinano lwesisombululo ngexesha le-hydrolysis e-acid-catalyzed hydrolysis lutshintsha i-hydrogen bonding ngaphakathi kwe-polymer, nto leyo echaphazela ngokusisiseko ukufikeleleka kwe-enzyme kunye namazinga okubuyisela i-monomer. Ulawulo loxinano olunganelanga kweli nqanaba lukhokelela ekuguqulweni okanye ekuchithekeni okungaphelelanga, okuchaphazela ngokuthe ngqo isivuno sezityalo kunye nemilinganiselo yozinzo.
Amaxwebhu avela kwiimveliso zeekhemikhali zoshishino axela ukuba ukujonga uxinano oluzenzekelayo kubalulekile ekuveliseni ityuwa ehambelanayo, ecocekileyo kakhulu, ngelixa ngaxeshanye kunciphisa inkunkuma, ukuphucula imveliso, kunye nokuqinisekisa ukuthotyelwa kweemfuno zenkqubo. Oku kuye kwabaluleka njengoko uxinzelelo lolawulo kunye nolozinzo lusanda, lufuna ulawulo lwenkqubo oluqinileyo kunye nokusebenza ngcono.
Iindlela zokulinganisa uxinano lolwelo
Ngokwembali, iindlela ezifana ne-pycnometry okanye ii-hydrometers zazilinganisa uxinano lwesisombululo setyuwa kodwa zazingenachaneko kwaye zingenelele ngesandla, nto leyo eyenza ukuba zingafaneleki ukujongwa rhoqo kwemizi-mveliso. Iindlela zanamhlanje zoshishino zikhetha izixhobo ezizenzekelayo nezichanekileyo kakhulu.
Iimitha zoxinano lwe-U-tube ezijikelezayo zibonakala njengomgangatho weshishini wokulinganisa uxinano lwesisombululo setyuwa. Lo mgaqo ulula: ityhubhu enomfanekiso we-U, egcwele isisombululo setyuwa, iyashukuma kwisantya esitshintsha ngotshintsho kuxinano lwe-fluid. Ngenxa yokuba ulwelo oluxineneyo lubangela ukuba ityhubhu ishukume kancinci, izixhobo ze-elektroniki ezinobuthathaka zilinganisa olu tshintsho lwesantya kwaye ziluguqulele kwisantya soxinano oluthe ngqo.
Ukukhethwa kwezinto ezisetyenziswa kwiityhubhu, ezifana nentsimbi engagqwaliyo okanye ii-alloys ezikhethekileyo, kukhokelwa kukuhambelana kweekhemikhali nezisombululo zetyuwa. Ezi mitha zisebenza ngokuthembekileyo kumgca wemveliso kwaye zibonelela ngeziphumo ezikhawulezayo neziphindaphindwayo, ezenza zilungelelaniswe kakuhle nemeko yokwenziwa kwetyuwa ye-nylon 66.
I-Lonnmeter igxile kwiimitha zoxinano eziqinileyo ezicwangciselwe iimeko ezinzima zoshishino, ukuqinisekisa ukusebenza okuzinzileyo kunye nokulinganiswa okuphindaphindiweyo nakwiindawo ezinoburhalarhume beekhemikhali. Iimitha zoxinano ezicwangciselwe ngqo kwiipayipi zenkqubo, okuvumela ukujonga ngexesha langempela ukuxinana kwetyuwa ngexesha leenkqubo zebhetshi kunye neziqhubekayo ezinxulumene nokulungiswa kwetyuwa ye-nylon 66.
Ukulinganisa ezi mitha kubalulekile ukuze kufundwe ngokuchanekileyo. Ukulinganisa kubandakanya izisombululo ezisemgangathweni kwiingxinano ezichaziweyo ukuze kumiselwe iindawo zokubhekisa ngaphambi kokuba isixhobo sisetyenziswe kunye nolwelo lwenkqubo. Oku kuqinisekisa ukuba amaxabiso alinganisiweyo abonakalisa uxinaniso lwetyuwa yokwenyani—kubalulekile ekugcineni iimeko zokusabela ngaphakathi kokunyamezelana okungqongqo.
Ukudibanisa Idatha yoBuninzi boLawulo lweNkqubo
Ukudibanisa umlinganiselo woxinano ngexesha langempela kulawulo lwenkqubo oluzenzekelayo kuphakamisa kakhulu ukusebenza kokusebenza kwimveliso yetyuwa ye-nylon 66. Ngokufaka iimitha zoxinano ezingaphakathi ngqo kwinkqubo yokuvelisa, idatha yoxinano igcinwa rhoqo kwaye idluliselwe kwinkqubo yolawulo.
Iinkqubo ezizenzekelayo zithelekisa ukufundwa koxinano oluphilayo kunye namaxabiso afanelekileyo acwangcisiweyo kwisisombululo setyuwa. Xa kufunyenwe ukuphambuka, inkqubo inokwenza uhlengahlengiso lwexesha langempela—njengokutshintsha ukuhamba kwe-reactant, ukulungisa umxholo wamanzi, okanye ukuguqula iindawo zokubeka ubushushu—ukubuyisela inkqubo ngaphakathi kweenkcukacha ngaphandle kokungenelela komqhubi.
Le ndlela ithintela ukuguquguquka kweqela ukuya kwelinye, ibonelela ngomjikelo wempendulo ovaliweyo ojongana nokushukuma kwenkqubo, ukufunxwa kwamanzi okungalindelekanga, okanye ukunganyamezeli ngokupheleleyo ngexesha langempela. Kubalulekile ekuphuculeni iimeko zepolymerization ezilandela ukulungiswa kwetyuwa. Umzekelo, uxinano lwesisombululo setyuwa oluhambelanayo luhambelana nobunzima bemolekyuli yepolymer kunye ne-viscosity eqikelelweyo, nto leyo exhasa uzinzo oluphezulu loomatshini kunye nobushushu olufunekayo kwiimveliso ze-nylon ezingama-66 ezenziwe ngobunjineli.
Imizekelo evela kwimisebenzi ephambili yemizi-mveliso igxininisa ukuba ukuhlanganiswaukufundwa koxinano kwi-intanethingemilinganiselo eqhelekileyo—njengobushushu kunye ne-pH—yenza ukuba inkqubo ye-multi-factor ibe ngcono. Isiphumo kukuba i-throughput efanayo kakhulu, imveliso encitshisiweyo engakhange ichazwe, kunye nokusetyenziswa kwamandla aphantsi kunye nezinto ezibonakalayo ngexesha le-nylon 66 salt reaction. Olu manyano ngoku luthathwa njengolona hlobo lubalaseleyo kushishino lweekhemikhali, lusebenzela zombini iinjongo zokuqinisekisa umgangatho kunye nokuzinza kwimigca yemveliso ye-polymer yanamhlanje.
Ukusuka kwiTyuwa ukuya kwiNylon 66 Polymer: Ukufuma kwePolycondensation kunye nokuLungiswa emva kokuCoca
Ukulawula ulwakhiwo lweemolekyuli kunye neempawu ze-nylon 66 kufuna ulawulo oluchanekileyo lweeparamitha ezininzi zenkqubo ngexesha le-pre-polycondensation, i-melt polycondensation, kunye ne-post-processing. Isigaba ngasinye—ukusuka ekwakhiweni kwesisombululo setyuwa sokuqala ukuya kuvavanyo lokugqibela lomgangatho we-pellet—sidlala indima ebalulekileyo ekuveliseni i-resin ye-nylon 66 yomgangatho wezimboni.
Iiparamitha ze-Pre-Polycondensation
Inyathelo le-polycondensation, apho i-nylon 66 idalwa nge-reaction ye-adipic acid kunye ne-hexamethylenediamine, inovelwano kakhulu kwiinguqu zokusebenza. Ubushushu, uxinzelelo, kunye nexesha lokuphendula zezona zinto zinempembelelo kubunzima be-molecular kunye ne-intrinsic viscosity. I-Industrial polycondensation isebenza phakathi kwama-280°C nama-300°C. Ubushushu obuphezulu kolu luhlu, kunye namaxesha okuphendula ande, kwandisa umngcipheko wokuwohloka kobushushu, kwazisa iimveliso eziphumayo kunye nokunciphisa uzinzo lwe-polymer lwexesha elide. Ukwandisa ubunzima be-molecular kunye nokugcina usasazo oluncinci lobunzima be-molecular, kuqaliswa ukuhla koxinzelelo lwexeshana ukukhawulezisa ukususwa kwamanzi okupholisa, ngelixa ixesha lokuphendula lilawulwa ngokuqinileyo ukuthintela ukufuma okugqithisileyo okanye ukuqhekeka kweketanga.
Uxinzelelo lulawula ngokuthe ngqo ukuguquka kweemveliso eziguquguqukayo. Ukuqala ngoxinzelelo oluphezulu kunceda kwizinga lokuqala lokusabela, emva koko uxinzelelo luyancitshiswa kancinci ukuze kube lula ukususwa kwamanzi ngokufanelekileyo; ulawulo olungafanelekanga kweli nqanaba luphakamisa iintsalela ze-monomer kwaye lunokubangela iibhetshi zemveliso ezingalinganiyo. Umzekelo, ukulungisa iiprofayili zoxinzelelo lwe-reactor nge-0.1 MPa encinci kubonakalisiwe ukuba kuphucula ukufana kwe-molecular chain kunye namandla okutsalwa ngaphezulu kwe-8% xa kuthelekiswa neenkqubo ezingalawulwayo.
I-pH yesisombululo sokuqala setyuwa, nangona ingeyiyo inguqu ephambili ngexesha leenkqubo zokunyibilika kobushushu obuphezulu, inempembelelo kumanyathelo angaphambili asekelwe kwisisombululo okanye emva kwe-polycondensation. Ukugcina i-pH isondele kwi-neutral (ngesiqhelo phakathi kwe-7 kunye ne-7.5) kubalulekile ekufezekiseni i-stoichiometry elinganayo phakathi kwe-hexamethylenediamine kunye ne-adipic acid, okuchaphazela ukulingana kokusasazwa kobude betsheyini kunye nophuhliso lweendawo zekristale ngaphakathi kwepolymer. Ukungafani kwe-pH kunokukhokelela kwimixube engeyiyo ye-stoichiometric, okuqhuba ukuxinana okugqithisileyo okanye ii-linkages ezingenakunyibilika, ezibonakala njengokunciphisa amandla oomatshini kunye nokutshintsha kwekristale kwi-resin egqityiweyo. Iindlela zohlalutyo—ezifana ne-differential scanning calorimetry (DSC) kunye ne-X-ray diffraction (XRD)—zityhila ukwanda kwe-crystalline uniformity kunye neempawu zoomatshini eziphuculweyo zeesampulu ze-nylon ezingama-66 eziphuculweyo ze-pH.
Ukunyibilika kwePolymerization kunye nokuPhucula uMgangatho
Ukunyibilika kwe-industrial melt polycondensation ye-nylon 66 kwenza ukuba i-synthesis ihambelane ngqo ngaphandle kwezinyibilikisi, ixhasa ukujikeleza kwefayibha okuqhubekayo kunye nemveliso ye-resin enkulu. Ukufezekisa ubunzima be-molecular obufunekayo kuxhomekeke kulawulo oluchanekileyo lwexesha lokuphendula, ubushushu, kunye nokucoca kwe-monomer. Ukuphambuka kwiiprofayili zenkqubo ekujoliswe kuyo kudla ngokukhokelela ekwandeni kwe-melt viscosity, umngcipheko ophezulu wokushisa kakhulu kwendawo, kunye nokudibanisa kwangaphambili okanye ukonakala.
Le nkqubo iqhubela phambili ngamanqanaba, iqala ngokunyibilika kwetyuwa, ukusabela ngomthamo ongaguqukiyo phantsi koxinzelelo olulawulwayo, uze emva koko unciphise uxinzelelo ngokucothayo ukuze kuphume amanzi. Iindlela zokulinganisa uxinano lolwelo olungaphakathi zisebenza njengeendlela eziphambili zokuphendula ngeli xesha, zibonelela ngokubeka iliso ngexesha langempela ukuqinisekisa ukulingana kunye nokwenza ukuba kubekho uhlengahlengiso lweendawo zokusebenza zokukhula kwetyathanga elifanelekileyo. Izixhobo ezifana nemitha yoxinano olungaphakathi evela eLonnmeter, xa zilinganiswe ngokuchanekileyo ngamanzi okulinganisa alungiselelwe ngegravimetrically, zivumela uvavanyo oluchanekileyo lwesisombululo setyuwa kunye noxinano lwepolymer melt. Oku kuqinisekisa ukuhambelana kwebhetshi ukuya kwibhetshi kunye nokuchongwa ngexesha elifanelekileyo kokuhamba kwenkqubo.
Emva kokuphola, i-nylon enyibilikisiweyo 66 iyakhutshwa ize ikhutshwe ngokukhawuleza. Ukupholisa ngokukhawuleza—ngesiqhelo ngamanzi okanye ngomoya onyanzelekileyo—kuyimfuneko ukuthintela ukuhlangana kwe-pellet kunye nokugcina ukuthembeka kobukhulu. Ubungakanani be-pellet kunye nokuguquguquka kwemilo kunokwenzeka ukuba amazinga okupholisa acotha kakhulu okanye awaguquguquki, nto leyo echaphazela kakubi ukuphathwa kunye nokucutshungulwa kwezinto ezisezantsi.
Inqanaba elilandelayo elibalulekileyo kukomisa. I-resin ye-nylon 66 i-hygroscopic ngokwendalo; umphezulu oseleyo okanye amanzi afunxiweyo akhokelela ekuwohlokeni kwe-hydrolytic ngexesha lokunyibilika okulandelayo, okubangela ukunciphisa ubunzima beemolekyuli, iimpawu zokuhamba kakubi, kunye neziphene ezibonakalayo kwiindawo ezibunjiweyo. Ukomisa kufuneka kwenziwe phantsi komoya ophantsi wombethe, kunye nobushushu obulawulwayo obungadluli ukunyamezela kwepolymer ukuthintela ukuthamba kwangaphambi kwexesha okanye ukuba tyheli. Izifundo zibonisa ukuba umxholo womswakama ongaphezulu kwe-0.2% unyusa kakhulu ukulahleka kwe-viscosity kwaye unciphisa amandla okugqibela emveliso.
Ukujonga umgangatho rhoqo, kuquka ukulinganiswa komswakama kunye nobungakanani be-Karl Fischer, kuyinxalenye yendlela engcono yokuqinisekisa ukuba iiparameter zokomisa zivelisa ii-pellets ezizinzileyo nezincitshisiweyo. Ukuphucula inyathelo ngalinye lokucubungula emva kokwenziwa kwe-pellets ukuya kwindawo yokugcina izinto, kubonakalisiwe ukuba kukhokelele ekuqineni okuphezulu kunye namandla empembelelo xa kuthelekiswa nemigaqo engalawulwanga ngokwaneleyo.
Ukuqinisekisa Ukuthembeka Kwemveliso Kuyo Yonke Imigca Yemveliso Yemizi-mveliso
Ukulungelelana kwimveliso kubalulekile, njengoko i-polymer ye-nylon yemizi-mveliso engama-66 ihanjiswa kwiindidi ezahlukeneyo zemveliso—iifayibha, iindawo zobugcisa, iifilimu—nganye ineemfuno ezithile zokusebenza. Oku kufuna uhlengahlengiso olucwangcisiweyo kwiiparameter zenkqubo kwibanga ngalinye:
- I-nylon yodidi lwefayibha 66 ixhamla kubunzima obuphezulu beemolekyuli ukuze ibe namandla oomatshini, nto leyo efuna ixesha elide lokuxinana kwe-polycondensation kunye nokuchaneka okwandisiweyo kulawulo lobushushu.
- Amanqanaba okubumba ngenaliti anokunyamezela ubunzima obuphantsi beemolekyuli kodwa afuna ukoma okuphezulu kwepellet kunye nokuchaneka kwejometri ukuthintela iziphene zokucubungula.
Ukuhlolwa komgangatho wokugqibela kuxhomekeke kwiikhrayitheriya zokwamkelwa kwemveliso ethile. Oku kuquka iindlela ezimiselweyo zokulinganisa i-intrinsic viscosity, i-modulus, ukumelana nempembelelo, kunye, ngokubalulekileyo, nomxholo womswakama. Ukuhlolwa kwenkangeleko yomzimba yokujonga ukufana kwe-pellet kunye nokungabikho kombala kuxhaswa luvavanyo lwelebhu lweempawu zoomatshini kunye nobushushu. Kuphela zibhetshi ezihlangabezana nazo zonke iimetrikhi eziphambili ezikhutshwayo kwizicelo zoshishino—iinkcukacha zishwankathelwe kwiinkcukacha zobugcisa ezibhekisa kwiiprotokholi ze-ASTM kunye ne-ISO.
Ukubeka iliso kuxinano kukwadlala indima yokuthintela; ukusebenzisa iindlela zokulinganisa uxinano lolwelo ngexesha lokulungiselela ityuwa kunye nezigaba zokunyibilika kwepolymer kuqinisekisa umgangatho ofanayo webhetshi kwaye kwenza kube lula ukubona ngokukhawuleza ukuphambuka okunokuphazamisa ukuthembeka kokusetyenziswa kokugqibela. Ukulinganisa iimitha zoxinano, ezifana nezo zenziwe yiLonnmeter, kwenziwa ngemigangatho eqinisekisiweyo ukugcina ulawulo oluqinileyo lwenkqubo kunye nokuphindaphinda, okubalulekileyo ekukhuliseni imveliso kwimigca emininzi yemveliso yemizi-mveliso.
Ngolawulo olungqongqo ngexesha le-pre-polycondensation, i-melt polymerization echanekileyo, kunye ne-post-processing engqongqo, abavelisi be-nylon 66 bahlala benikezela ngee-resin ezithembekileyo, ezihambelana neemfuno eziguqukayo zeemarike zeemveliso zoshishino.
Imibuzo Ebuzwa Rhoqo (Ii-FAQ)
Yintoni ityuwa ye-nylon 66, kwaye kutheni ibalulekile kwimveliso ye-polymer?
Ityuwa ye-nylon 66, eyaziwa ngeekhemikhali njenge-hexamethylenediammonium adipate, isebenza njengesiseko semveliso ye-nylon 66 polymer. Yenziwa nge-reaction echanekileyo ye-1:1 yokunganyamezeli phakathi kwe-hexamethylenediamine kunye ne-adipic acid. Le ndlela iphakathi ilawula umxholo weqela lokugqibela kunye nobude betsheyini ye-polyamide yokugqibela. Ityuwa ye-nylon 66 ecocekileyo kakhulu iyimfuneko ukuze kufezekiswe amandla ahambelanayo oomatshini, uzinzo lobushushu, kunye nokumelana nokuguguleka kwiiplastiki zobunjineli. I-Off-stoichiometry okanye ukungcola kweli nyathelo kuphazamisa ukusebenza kakuhle kwe-polymerization elandelayo kwaye kunciphisa umgangatho wemveliso yokugqibela, okwenza ukulungiswa kwetyuwa kube yinto ebalulekileyo kwinkqubo yokuvelisa i-nylon 66 polymer.
Inkqubo yokulungiselela ityuwa ye-nylon 66 ilungiswa njani ukuze icoceke?
Inkqubo yokwenziwa kwetyuwa ye-nylon 66 ixhomekeke ekongezweni okulawulwayo, kancinci kancinci kwee-reactants. Ukongezwa kwe-hexamethylenediamine ngokwezigaba okanye ngokwehlayo kwi-adipic acid phantsi komthetho ongqongqo wobushushu, oqhele ukuba malunga ne-210°C kunye ne-1.8 MPa, kunciphisa ukugqithisa kwendawo, kuthintela iimveliso ezingafunekiyo, kwaye kuqinisekisa umlinganiselo we-stoichiometric. Igesi engasebenziyo, efana ne-nitrogen, ikhusela impendulo kwi-oxidation engafunekiyo. Ukubeka iliso rhoqo kwi-pH kunye ne-UV index kuqinisekisa iimeko eziphantse zibe ne-neutral kunye nokungabikho kweemveliso ezinemibala, ezizimpawu zetyuwa ecocekileyo kakhulu. Le nkqubo ilawulwayo ivumela ukuveliswa kwezisombululo zetyuwa ezingenambala, ezizinzileyo, nezisebenzayo ezifanelekileyo kwi-polymerization ethe ngqo.
Ibaluleke ngantoni intsingiselo yokubeka esweni uxinano kwinkqubo yokulungiselela ityuwa?
Ukujonga uxinano lwesisombululo setyuwa kubalulekile kulawulo lwenkqubo kunye nokuqinisekiswa komgangatho ngexesha lokulungiselela ityuwa ye-nylon 66. Uxinano lwesisombululo, olulinganiswa ngexesha langempela, luyimbonakaliso ethe ngqo yoxinzelelo kunye nokuphelela kwempendulo yokunganyamezeli. Amaxabiso azinzileyo, axineneyo ekujoliswe kuwo aqinisekisa ukuba umlinganiselo we-reactant uyagcinwa kwaye ukuguqulwa kufikelele esiphelweni. Oku kunceda ukunciphisa ukuphambuka kwi-polymerization esezantsi, kuthintela ukwakheka kwamaqhezu anobunzima obuphantsi, kwaye kuxhasa umgangatho wemveliso ohambelanayo. Ukusebenzisa imitha yoxinano lolwelo kuqinisekisa ukuba ezi parameters zihlala ngaphakathi kwemida yokusebenza engqongqo, kuqinisa ukuthembeka kuyo yonke imigca yemveliso yeekhemikhali zoshishino.
Isebenza njani i-neutralization reaction ekulungiseleleni ityuwa ye-nylon 66?
Kwimpendulo yetyuwa ye-nylon 66, i-hexamethylenediamine (isiseko se-diamine) iphendula kunye ne-adipic acid (i-dicarboxylic acid) kwiimilinganiselo ze-stoichiometric. Impendulo ngokusisiseko yi-neutralization: NH2-(CH2)6-NH2 + HOOC-(CH2)4-COOH → (NH3+)-(CH2)6-(NH3+)(-OOC-(CH2)4-COO-) + H2O. Ukuze kwenziwe ityuwa efanelekileyo, le nkqubo ifuna ulawulo oluchanekileyo lokongeza i-reactant, ubushushu, kunye ne-pH, njengoko nokuphambuka okuncinci kunokubangela ukuguqulwa okungaphelelanga okanye iimpendulo ezingafunekiyo. Ukusebenza kakuhle kwale mpendulo kumisela isakhiwo se-molecular kunye nokusebenza kwe-polymer ye-nylon 66 ephumayo.
Zeziphi izixhobo ezisetyenziselwa ukulinganisa uxinano lolwelo kwimveliso yetyuwa ye-nylon 66 yemizi-mveliso?
Ukulinganiswa koxinano lwesisombululo setyuwa ngokuchanekileyo yinxalenye ephambili yokuqinisekiswa kwenkqubo kwimveliso enkulu ye-nylon 66. Iimitha zoxinano lwedijithali olungaphakathi, ezifana nee-densitometers ze-U-tube ezijikelezayo, zihlala zisetyenziswa kwiindawo zoshishino. Ezi zixhobo zibonelela ngokufundwa koxinano oluqhubekayo, ngexesha langempela, olunceda abaqhubi ukuba balungise amazinga okutya, umlinganiselo we-reactant, kunye neemeko zobushushu ukuze zihambelane neenkcukacha zenkqubo ekujoliswe kuzo. I-Lonnmeter yenza iimitha zoxinano olungaphakathi eziqinileyo kunye neemitha ze-viscosity ezingaphakathi ezilungele kakuhle eli nqanaba lokusetyenziswa kwezoshishino. Ukulinganiswa rhoqo kwezi zixhobo kuqinisekisa ukusebenza okuthembekileyo nokuphindaphindwayo, okubalulekileyo ekugcineni ukuthembeka komgca wemveliso yeekhemikhali kunye nokuxhasa ulawulo lomgangatho oluqinileyo.
Ixesha leposi: Disemba-18-2025
