1. Iintlobo ze-thickeners kunye ne-thickening mechanism
(1) Isityebi esingaphiliyo:
Ii-inorganic thickeners kwiinkqubo ezisekwe emanzini ikakhulu ludongwe. Njenge: bentonite. I-Kaolin kunye nomhlaba we-diatomaceous (icandelo eliphambili yi-SiO2, enesakhiwo esinamaqhekeza) ngamanye amaxesha asetyenziswa njengama-thickeners ancedisayo kwiinkqubo zokujiya ngenxa yeempawu zabo zokunqunyanyiswa. I-Bentonite isetyenziswa ngokubanzi ngenxa yokunyuka kwayo kwamanzi. I-Bentonite (i-Bentonite), eyaziwa ngokuba yi-bentonite, i-bentonite, njl., i-mineral engundoqo ye-bentonite yi-montmorillonite equlethe ixabiso elincinci le-alkali kunye ne-alkaline yomhlaba isinyithi i-hydrous aluminosilicate minerals, eyeqela le-aluminosilicate, ifomula yayo yeekhemikhali jikelele yile: (Na ,Ca)(Al,Mg)6(Si4O10)3(OH)6•nH2O. Ukwandisa ukusebenza kwe-bentonite kubonakaliswa ngumthamo wokwandiswa, oko kukuthi, umthamo we-bentonite emva kokuvuvukala kwi-dilute hydrochloric acid isisombululo sibizwa ngokuba yi-expansion capacity, echazwe kwi-ml / gram. Emva kokuba i-bentonite thickener ifunxa amanzi kunye nokudumba, umthamo unokufikelela kumaxesha amaninzi okanye amatyeli alishumi ngaphambi kokuba ufunxe amanzi, ngoko unokumiswa kakuhle, kwaye ngenxa yokuba i-powder kunye nobukhulu beqhekeza elincinci, ihluke kwezinye iipowders kwi-coating. inkqubo. Umzimba ulungelelanise kakuhle. Ukongezelela, ngelixa uvelisa ukumiswa, kunokuqhuba ezinye iipowder ukuvelisa umphumo othile wokuchasana ne-stratification, ngoko kunceda kakhulu ukuphucula ukuzinza kokugcinwa kwenkqubo.
Kodwa ezininzi ze-bentonite ezisekelwe kwi-sodium ziguqulwa kwi-bentonite esekelwe kwi-calcium ngokuguqulwa kwe-sodium. Ngexesha elifanayo le-sodiumization, inani elikhulu leeion ezintle ezifana ne-calcium ions kunye ne-sodium ions ziya kuveliswa. Ukuba umxholo wale cations kwinkqubo iphezulu kakhulu, isixa esikhulu sentlawulo yokungathathi hlangothi kuya kuveliswa kwiintlawulo ezingalunganga kumphezulu we-emulsion, ngoko ke ukuya kuthi ga kwinqanaba elithile, Inokubangela iziphumo ebezingalindelekanga ezifana nokudumba kunye ne-flocculation. i-emulsion. Kwelinye icala, ezi ion calcium nazo ziya kuba neziphumo ebezingalindelekanga kwi-sodium ityuwa dispersant (okanye i-polyphosphate dispersant), ibangela ukuba ezi dispersants ziphele kwinkqubo yokwaleka, ekugqibeleni zikhokelele ekulahlekeni kokusasazwa, kwenze isambatho sibe ngqindilili, ngqindilili okanye ngqindilili. Izantyalantyala zemvula kunye nokuntlithwa kwamanzi kwenzeka. Ukongezelela, i-thickening effect ye-bentonite ixhomekeke kwi-powder ukuze ithathe amanzi kunye nokwandisa ukuvelisa ukumiswa, ngoko kuya kuzisa umphumo oqinileyo we-thixotropic kwinkqubo yokugqoka, engathandeki kakhulu kwiingubo ezifuna imiphumo emihle yokulinganisa. Ke ngoko, i-bentonite inorganic thickeners ayifane isetyenziswe kwiipeyinti zelatex, kwaye isixa esincinci kuphela sisetyenziswa njenge-thickeners kwiipeyinti ze-latex ezisezantsi okanye iipeyinti ze-latex ezixutywe. Nangona kunjalo, kwiminyaka yakutshanje, ezinye iinkcukacha zibonise ukuba i-Hemmings' BENTONE®LT. i-organic modified kunye ne-hectorite esulungekileyo ine-anti-sedimentation efanelekileyo kunye nemiphumo ye-atomization xa ifakwe kwiinkqubo zokutshiza ezingenamoya ze-latex zepeyinti.
(2) Iselulosi ether:
I-Cellulose ether yipolymer yendalo ephezulu eyenziwe yi-condensation ye-β-glucose. Ukusebenzisa iimpawu zeqela le-hydroxyl kwiringi ye-glucosyl, i-cellulose inokungena kwiimpendulo ezahlukeneyo ukuvelisa uthotho lwezinto eziphuma kuyo. Phakathi kwazo, iimpendulo ze-esterification kunye ne-etherification zifunyenwe. I-cellulose ester okanye i-cellulose ether derivatives zezona zibalulekileyo ze-cellulose derivatives. Iimveliso ezisetyenziswa ngokuqhelekileyo yi-carboxymethyl cellulose,i-hydroxyethyl cellulose, i-methyl cellulose, i-hydroxypropyl methyl cellulose kunye nokunye. Ngenxa yokuba i-carboxymethyl cellulose iqulethe i-ion yesodium enyibilika ngokulula emanzini, ayinakuxhathisa amanzi, kwaye inani lezinto ezithatha indawo kwikhonkco layo eliphambili lincinci, ngoko ke iboliswa ngokulula kukuhlwa kwebhaktheriya, inciphisa i-viscosity yesisombululo samanzi kwaye iyenze. enukayo, njl njl. I-Phenomenon, engafane isetyenziswe kwipeyinti ye-latex, isetyenziswa ngokubanzi kwi-low-grade polyvinyl alcohol glue paint and putty. Izinga lokunyibilika kwamanzi e-methylcellulose ngokubanzi lingaphantsi kancinci kunelo le-hydroxyethylcellulose. Ukongezelela, kunokubakho inani elincinci lezinto ezingenakunyibilika ngexesha lokutshatyalaliswa, okuya kuchaphazela ukubonakala kunye nokuvakalelwa kwefilimu yokugqoka, ngoko ke ayifane isetyenziswe kwipeyinti ye-latex. Nangona kunjalo, ukuxinana komphezulu wesisombululo se-methyl aqueous singaphantsi kancinane kunezinye izisombululo ze-cellulose ezinamanzi, ngoko ke sisityebi esilungileyo se-cellulose esisetyenziswa kwi-putty. IHydroxypropyl methylcellulose ikwayi-cellulose thickener esetyenziswa kakhulu kwindawo ye-putty, kwaye ngoku isetyenziswa ikakhulu kwi-samente-based okanye kwi-lime-calcium-based putty (okanye ezinye izibophelelo ze-inorganic). I-Hydroxyethyl cellulose isetyenziswa kakhulu kwiinkqubo zepeyinti ye-latex ngenxa yokunyibilika kwayo kakuhle kwamanzi kunye nokugcinwa kwamanzi. Xa kuthelekiswa nezinye iiselulosi, inempembelelo encinci ekusebenzeni kwefilimu yokwambathisa. Izinto eziluncedo ze-hydroxyethyl cellulose ziquka ukusebenza kakuhle kokumpompa, ukuhambelana kakuhle, ukugcinwa kakuhle kozinzo, kunye nokuzinza okuhle kwe-pH ye-viscosity. Izinto ezingeloncedo kukungaphumeleli komgangatho kunye nokunganyangeki kakuhle kokuchaphaza. Ukuze kuphuculwe ezi ntsilelo, ukuguqulwa kwe-hydrophobic kubonakala. I-hydroxyethylcellulose enxulumene nesondo (HMHEC) njengeNatrosolPlus330, 331
(3) Iipolycarboxylates:
Kule polycarboxylate, ubunzima obuphezulu bemolekyuli buyi-thickener, kwaye ubunzima obuphantsi be-molecular is dispersant. Ngokukodwa babhengeza iimolekyuli zamanzi kwikhonkco eliphambili lenkqubo, eyandisa i-viscosity yesigaba esihlakaziweyo; Ukongeza, banokuphinda babhengezwe kumphezulu wamasuntswana e-latex ukwenza umaleko wokugquma, onyusa ubungakanani besuntswana le-latex, ityebisa i-hydration layer ye-latex, kwaye inyuse i-viscosity yesigaba sangaphakathi se-latex. Nangona kunjalo, olu hlobo lwe-thickener lunokusebenza okuphantsi kokuqina, ngoko ke ngokuthe ngcembe kupheliswa kwizicelo zokwaleka. Ngoku olu hlobo lwe-thickener lusetyenziswa ikakhulu kwi-thickening ye-paste yombala, kuba ubunzima bayo be-molecular bukhulu kakhulu, ngoko ke luncedo kwi-dispersibility kunye nokugcinwa kozinzo lokunamathisela umbala.
(4) Isityebi esinealkali-swellable:
Kukho iindidi ezimbini eziphambili zealkali-swellable thickeners: eziqhelekileyo zealkali-swellable thickeners kunye ne-associative alkali-swellable thickeners. Umahluko omkhulu phakathi kwabo ngumahluko kwiimonomers ezinxulumene nazo eziqulethwe kwikhonkco eliphambili lemolekyuli. I-Associative alkali-swellable thickeners i-copolymerized kunye ne-associative monomers ezinokuthi zibhengeze enye kwenye kwisakhiwo sekhonkco eliphambili, ngoko emva kwe-ionization kwisisombululo samanzi, i-intra-molecular okanye i-inter-molecular adsorption ingenzeka, ebangela ukuba i-viscosity yenkqubo inyuke ngokukhawuleza.
a. I-alkali-swellable thickener eqhelekileyo:
Uhlobo oluphambili lwabameli bemveliso ye-alkali-swellable thickener eqhelekileyo yi-ASE-60. I-ASE-60 ithatha i-copolymerization ye-methacrylic acid kunye ne-ethyl acrylate. Ngexesha lenkqubo ye-copolymerization, i-methacrylic acid i-akhawunti malunga ne-1/3 yomxholo oqinileyo, kuba ubukho bamaqela e-carboxyl benza ukuba ikhonkco le-molecular libe neqondo elithile le-hydrophilicity, kwaye linciphise inkqubo yokwenza ityuwa. Ngenxa yokunyanzeliswa kweentlawulo, amatyathanga e-molecular ayanda, okwandisa i-viscosity yenkqubo kwaye ivelise umphumo wokuqina. Nangona kunjalo, ngamanye amaxesha ubunzima be-molecular bukhulu kakhulu ngenxa yesenzo se-agent ye-cross-linking. Ngethuba lenkqubo yokwandisa i-molecular chain, i-molecular chain ayihlakazwanga kakuhle ngexesha elifutshane. Ngethuba lenkqubo yokugcina ixesha elide, i-molecular chain chain iyancipha ngokuthe ngcembe, ezisa i-Post-thickening of viscosity. Ukongeza, ngenxa yokuba kukho iimonomers ezimbalwa ze-hydrophobic kwitsheyina lemolekyuli yolu hlobo lokutyeba, akukho lula ukuvelisa ukuntsonkotha kwe-hydrophobic phakathi kweemolekyuli, ikakhulu ukwenza i-intramolecular mutual adsorption, ke olu hlobo lwe-thickener lunokusebenza okuphantsi kokuqina, ngoko kunjalo. ayifane isetyenziswe yodwa. Isetyenziswa ikakhulu ngokudityaniswa nezinye i-thickeners.
b. Umbutho (concord) uhlobo lwealkali ukudumba thickener:
Olu hlobo lwe-thickener ngoku luneentlobo ezininzi ngenxa yokukhethwa kwee-monomers ezidibeneyo kunye noyilo lwesakhiwo se-molecular. Ubume balo bekhonkco oluphambili lukwabandakanya i-methacrylic acid kunye ne-ethyl acrylate, kwaye i-monomers edibeneyo ifana ne-eriyali kwisakhiwo, kodwa inani elincinci lokusabalalisa. Ngala ma-monomers adibeneyo afana ne-octopus tentacles edlala indima ebalulekileyo ekusebenzeni kakuhle kwe-thickener. Iqela le-carboxyl kwisakhiwo lingathathi hlangothi kwaye lenza ityuwa, kwaye ikhonkco le-molekyuli likwafana ne-alkali-swellable thickener eqhelekileyo. Ukuchaswa kwentlawulo efanayo kwenzeka, ukuze ikhonkco lemolekyuli livuleleke. I-monomer edibeneyo kuyo iphinda ikhulise kunye ne-molecular chain, kodwa isakhiwo sayo siqulethe zombini i-hydrophilic chain kunye ne-hydrophobic chain, ngoko ke isakhiwo esikhulu se-micellar esifana ne-surfactants siya kuveliswa kwi-molecule okanye phakathi kwee-molecule. Ezi micelles ziveliswa yi-adsorption ye-adsorption ye-monomers yombutho, kwaye ezinye ii-monomers zombutho zithengisana ngomphumo wokuqhawula amasuntswana e-emulsion (okanye amanye amasuntswana). Emva kokuba ii-micelles ziveliswe, zilungisa i-emulsion particles, i-molecule yamanzi okanye amanye amasuntswana kwisistim kwimeko engatshintshiyo njengentshukumo ye-enclosure, ukwenzela ukuba ukuhamba kwezi molekyuli (okanye amaqhekeza) kubuthathaka kunye ne-viscosity ye ukwanda kwenkqubo. Ke ngoko, ukuqina kolu hlobo lwe-thickener, ngakumbi kwipeyinti ye-latex enomxholo ophezulu we-emulsion, ingaphezulu lee kunee-alkali-swellable thickeners eziqhelekileyo, ngoko ke isetyenziswa kakhulu kwipeyinti yelatex. Ummeli oyintloko wemveliso Uhlobo luyi-TT-935.
(5) I-Asociative polyurethane (okanye i-polyether) yokuqina kunye ne-agent yokulinganisa:
Ngokuqhelekileyo, i-thickeners inobunzima obukhulu be-molecular (efana ne-cellulose kunye ne-acrylic acid), kwaye amatyathanga abo e-molecular asoluliwe kwisisombululo samanzi ukwandisa i-viscosity yenkqubo. Ubunzima bemolekyuli ye-polyurethane (okanye i-polyether) incinci kakhulu, kwaye ikakhulu yenza umbutho ngokusebenzisana kwe-van der Waals yamandla ecandelo le-lipophilic phakathi kweemolekyuli, kodwa lo mbutho ubuthathaka, kwaye umbutho unokwenziwa phantsi kweemeko ezithile. amandla angaphandle. Ukwahlula, ngaloo ndlela ukunciphisa i-viscosity, kuhambelana nomgangatho wefilimu yokugqoka, ngoko inokudlala indima yokulinganisa i-agent. Xa i-shear force iphelile, inokuqalisa ngokukhawuleza ukudibanisa, kwaye i-viscosity yenkqubo iphakama. Le nto inenzuzo ekunciphiseni i-viscosity kunye nokwandisa umgangatho ngexesha lokwakha; kwaye emva kokuba i-shear force ilahlekile, i-viscosity iya kubuyiselwa ngokukhawuleza ukunyusa ubukhulu befilimu yokugqoka. Kwizicelo ezisebenzayo, sixhalabile ngakumbi malunga nesiphumo sokujiya se-asociative thickeners kwii-emulsions ze-polymer. Iinqununu eziphambili ze-latex ze-polymer nazo zithatha inxaxheba kwintlangano yenkqubo, ukwenzela ukuba olu hlobo lwe-ejenti yokuqina kunye ne-ejenti yokulinganisa nayo ibe nefuthe elihle lokuqina (okanye ukulinganisa) xa liphantsi kunogxininiso olubalulekileyo; xa ukugxininiswa kolu hlobo lwe-ejenti yokuqina kunye nokulinganisa Xa iphezulu kunokubaluleka kwayo emanzini ahlambulukileyo, inokwenza imibutho ngokwayo, kwaye i-viscosity iphakama ngokukhawuleza. Ngoko ke, xa olu hlobo lwe-ejenti yokuqina kunye nokulinganisa iphantsi kunogxininiso olubalulekileyo, ngenxa yokuba i-latex particles ithatha inxaxheba kwintlangano encinci, incinci isayizi ye-emulsion, i-association yomelele, kunye ne-viscosity yayo iya kwanda ngokunyuka kwe-emulsion. umthamo we-emulsion. Ukongeza, ezinye dispersants (okanye acrylic thickeners) ziqulathe izakhiwo hydrophobic, kunye namaqela abo hydrophobic basebenzisane nabo polyurethane, ukuze inkqubo iqulunqe isakhiwo womnatha enkulu, nto leyo ebangela ukutyeba.
2. Iimpembelelo ze-thickeners ezahlukeneyo ekuxhathiseni ukuhlukana kwamanzi kwipeyinti ye-latex
Ekuqulunqweni koyilo lweepeyinti ezisekelwe emanzini, ukusetyenziswa kwe-thickeners yikhonkco ebaluleke kakhulu, ehambelana neepropati ezininzi zepende ye-latex, njengokwakhiwa, ukuphuhliswa kombala, ukugcinwa kunye nokubonakala. Apha sigxininise kwimpembelelo yokusetyenziswa kwe-thickeners kwindawo yokugcina ipeyinti ye-latex. Ukususela kwintshayelelo engasentla, siyakwazi ukuba i-bentonite kunye ne-polycarboxylates: i-thickeners isetyenziswa kakhulu kwezinye iingubo ezikhethekileyo, ezingayi kuxoxwa apha. Siza kuxubusha ubukhulu becala i-cellulose esetyenziswa ngokuqhelekileyo, ukudumba kwealkali, kunye ne-Polyurethane (okanye i-polyether) i-thickeners, iyodwa kwaye idibene, ichaphazela ukuxhathisa ukwahlula kwamanzi kwiipende ze-latex.
Nangona ukujiya nge-hydroxyethyl cellulose iyodwa kuyingozi kakhulu ekwahlukaneni kwamanzi, kulula ukuyishukumisa ngokulinganayo. Ukusetyenziswa kanye kokudumba kwealkali ukujiya akunakwahlulwa kwamanzi kunye nemvula kodwa ukujiya kakhulu emva kokujiya. Ukusetyenziswa okukodwa kwe-polyurethane thickening, nangona ukwahlukana kwamanzi kunye nokugqithiswa emva kokuqina Ukuqina akubi kakhulu, kodwa imvula eveliswa yiyo inzima kwaye kunzima ukuyishukumisa. Kwaye ithatha i-cellulose ye-hydroxyethyl kunye ne-alkali ukudumba ukujiya ikhompawundi, akukho post-thickening, akukho mvula enzima, kulula ukuyishukumisa, kodwa kukho isixa esincinci samanzi. Nangona kunjalo, xa i-hydroxyethyl cellulose kunye ne-polyurethane zisetyenziselwa ukujiya, ukwahlukana kwamanzi yeyona nto inzima, kodwa akukho mvula enzima. I-alkali-swellable thickening kunye ne-polyurethane zisetyenziswa kunye, nangona ukwahlukana kwamanzi ngokusisiseko akukho kuhlukana kwamanzi, kodwa emva kokuqina, kunye nentlenga esezantsi kunzima ukuyishukumisa ngokulinganayo. Kwaye owokugqibela usebenzisa i-cellulose encinci ye-hydroxyethyl kunye nokudumba kwe-alkali kunye nokujiya kwe-polyurethane ukuze ibe nesimo esifanayo ngaphandle kwemvula kunye nokwahlukana kwamanzi. Ingabonwa ukuba kwinkqubo ye-emulsion ye-acrylic ecocekileyo ene-hydrophobicity eyomeleleyo, kunzulu ngakumbi ukujiya isigaba samanzi nge-hydrophilic hydroxyethyl cellulose, kodwa inokushukunyiswa ngokulula ngokulinganayo. Ukusetyenziswa okukodwa kokudumba kwe-alkali ye-hydrophobic kunye ne-polyurethane (okanye i-compound yabo) ukujiya, nangona ukusebenza kokwahlukana kwamanzi kubhetele, kodwa zombini ziyajiya emva koko, kwaye ukuba kukho imvula, kubizwa ngokuba yimvula enzima, enzima ukuyishukumisa ngokulinganayo. Ukusetyenziswa kwe-cellulose kunye ne-polyurethane compound thickening, ngenxa yowona mahluko ude kakhulu kumaxabiso e-hydrophilic kunye ne-lipophilic, kubangela ukwahlukana kwamanzi amaninzi kunye nemvula, kodwa intlenga ithambile kwaye kulula ukuyishukumisa. Ifomula yokugqibela inomsebenzi ongcono wokulwa nokwahlukana kwamanzi ngenxa yebhalansi engcono phakathi kwe-hydrophilic kunye ne-lipophilic. Ngokuqinisekileyo, kwinkqubo yoyilo lwangempela lwefomula, iintlobo ze-emulsions kunye ne-wetting kunye ne-dispersing agents kunye nexabiso labo le-hydrophilic kunye ne-lipophilic kufuneka liqwalaselwe. Kuphela xa befikelela kwi-balance balance, inkqubo ingaba kwi-equilibrium ye-thermodynamic kwaye ibe nokuchasana kakuhle kwamanzi.
Kwinkqubo yokuqina, ukunyanzeliswa kwesigaba samanzi ngamanye amaxesha kuhamba kunye nokunyuka kwe-viscosity yesigaba seoli. Ngokomzekelo, sikholelwa ngokubanzi ukuba i-cellulose thickeners iqinisa isigaba samanzi, kodwa i-cellulose isasazwa kwisigaba samanzi.
Ixesha lokuposa: Dec-29-2022