I-Mechanism ye-Redispersible Emulsion Powder kwi-Dry Mix Mortar

Redispersible latex powder kunye nezinye izinto zokuncamathelisa inorganic (ezifana nesamente, slaked lime, gypsum, udongwe, njalo njalo) kunye aggregates ezahlukeneyo, fillers kunye nezinye izongezo [ezifana hydroxypropyl methylcellulose, polysaccharide (starch ether), ifayibha Fiber, njl.] kwidaka elomileyo elixutywe ngokuxubana ngokwasemzimbeni. Xa udaka olomileyo lwepowder lufakwe emanzini kwaye luxutywe, phantsi kwesenzo se-hydrophilic ekhuselayo ye-colloid kunye ne-mechanical shear force, i-latex powder particles inokusasazwa ngokukhawuleza emanzini, okwaneleyo ukwenza ngokupheleleyo i-latex powder edispersible ibe ngumgubo. ifilimu. Ukubunjwa komgubo werabha kuneempembelelo ezahlukeneyo kwiipropati ze-rheological zodaka kunye neempawu ezahlukeneyo zokwakha: ukudibanisa kwe-latex powder emanzini xa iphinde yachithwa, i-viscosities eyahlukeneyo ye-latex powder emva kokusasazeka, impembelelo kumxholo womoya. udaka kunye nokusasazwa kwamaqamza omoya, Ukusebenzisana phakathi komgubo werabha kunye nezinye izongezo kwenza ukuba umgubo welatex ohlukeneyo ube neziphumo zokwanda kwe-fluidity, ukwandisa i-thixotropy, kunye nokwanda kwe-viscosity.

Ngokuqhelekileyo kukholelwa ukuba indlela ye-latex powder ehlaziywayo yokuphucula ukusebenza kodaka olutsha kukuba: ukuxhamla kwe-latex powder, ngakumbi i-colloid ekhuselayo, emanzini xa ichithwa, kwandisa i-viscosity ye-slurry, kwaye iphucula ukudibanisa kwe-slurry. udaka lokwakha.

Emva kokuba udaka olusandul' ukuxutywa oluqulethe i-latex powder dispersion yenziwe, kunye nokufunxwa kwamanzi ngumgangatho wesiseko, ukusetyenziswa kwe-hydration reaction, kunye nokunyuka emoyeni, amanzi aya kuncipha ngokuthe ngcembe, amasuntswana e-resin aya kusondela ngokuthe ngcembe, ujongano. iya kuncipha ngokuthe ngcembe, kwaye iireyini ziya kuxubana ngokuthe ngcembe. ekugqibeleni yenziwe i-polymer kwifilimu. Inkqubo yokwenziwa kwefilimu ye-polymer ihlukaniswe ngamanqanaba amathathu. Kwinqanaba lokuqala, iinqununu ze-polymer zihamba ngokukhululekile ngendlela ye-Brownian motion kwi-emulsion yokuqala. Njengoko amanzi ephuma ngumphunga, ukuhamba kwamasuntswana ngokwendalo kuthintelwe ngakumbi nangakumbi, kwaye ukuxinana kobuso phakathi kwamanzi nomoya kuyawanyanzela ukuba alungelelanise ngokuthe ngcembe. Kwinqanaba lesibini, xa amasuntswana adibana nomnye, amanzi akuthungelwano ayaphuphuma ngeetyhubhu ze-capillary, kwaye uxinzelelo oluphezulu lwe-capillary olusetyenziswa kumphezulu wamasuntswana lubangela ukuba i-deformation ye-latex spheres idibanise, kwaye amanzi asele azalise iipores, kwaye ifilimu yenziwe ngokufanelekileyo. Inqanaba lesithathu, lokugqibela livumela ukusasazwa (ngamanye amaxesha kubizwa ngokuba yi-self-adhesion) yeemolekyuli ze-polymer ukuba zenze ifilimu yokwenene eqhubekayo. Ngexesha lokwenziwa kwefilimu, amasuntswana e-latex ahlala eyedwa ayadityaniswa abe sisigaba esitsha sefilimu enoxinzelelo oluphezulu. Ngokucacileyo, ukwenzela ukuba i-polymer powder ikwazi ukuphinda iphinde ikwazi ukwenza ifilimu kumdaka owenziwe lukhuni, kuyimfuneko ukuqinisekisa ukuba iqondo lokushisa elincinci lokubumba ifilimu (MFT) lingaphantsi kweqondo lokushisa lokunyanga lodaka.

I-Colloids - i-polyvinyl alcohol kufuneka ihlulwe kwinkqubo yefilimu ye-polymer. Oku akuyongxaki kwinkqubo yodaka lwesamente yealkaline, kuba i-alkali ye-polyvinyl utywala iya kuhlanjululwa yi-alkali eveliswa yi-cement hydration, kwaye i-adsorption ye-quartz material iya kwahlula ngokuthe ngcembe i-polyvinyl alcohol kwisistim, ngaphandle kwe-hydrophilic protective colloid. , Ifilimu eyenziwe yi-dispersion ye-time-dispersible powder latex powder, yona ngokwayo i-insoluble emanzini, ayikwazi ukusebenza kuphela kwiimeko ezomileyo, kodwa nakwiimeko zokucwiliswa kwamanzi ixesha elide. Kakade ke, kwiinkqubo ezingezizo zealkaline, ezifana negypsum okanye i-filler-only systems, kuba utywala bepolyvinyl busekho ngokuyinxenye kwifilimu yepolymer yokugqibela, echaphazela ukunganyangeki kwamanzi kwefilimu, xa ezi nkqubo zingasetyenziswanga amanzi exesha elide. ukuntywiliselwa, kwaye i-polymer iseneempawu zayo ezizodwa zoomatshini, kwaye i-polymer powder edispersible isenokusetyenziswa kwezi nkqubo.

Ngokuqulunqwa kokugqibela kwefilimu yepolymer, inkqubo eyenziwe ngezinto ezingaphiliyo kunye ne-organic binder zenziwa kudaka olunyangisiweyo, oko kukuthi, i-skeleton brittle and hard skeleton eyenziwe ngezinto zehydraulic, kwaye i-latex powder ephinda ihlakazwe yenza ifilimu phakathi kwesithuba kunye umgangatho oqinileyo. inethiwekhi ebhetyebhetye. Amandla okuqina kunye nokubambisana kwefilimu ye-polymer resin eyenziwe ngumgubo we-latex iphuculwe. Ngenxa yokuguquguquka kwepolymer, isakhono sokuguqulwa siphezulu kakhulu kunokwakheka kwelitye le-samente, ukusebenza kwe-deformation yodaka kuphuculwe, kwaye umphumo wokusabalalisa uxinzelelo uphuculwe kakhulu, ngaloo ndlela kuphuculwe ukuxhathisa kokuqhekeka kodaka. .

Ngokunyuka komxholo we-latex powder ephindayo, yonke inkqubo iphuhlisa kwiplastiki. Kwimeko yomxholo ophezulu we-latex powder, isigaba se-polymer kumdaka ophilisiwe ngokuthe ngcembe udlula isigaba semveliso ye-inorganic hydration, kwaye udaka luya kutshintsha utshintsho olusemgangathweni kwaye lube yi-elastomer, ngelixa imveliso ye-hydration ye-samente iba "i-filler". “. Amandla anqabileyo, u-elasticity, ukuguquguquka kunye nokutywinwa kodaka oluguqulwe ngumgubo we-latex ophindwe kabini zonke ziphuculwe. Ukudityaniswa komgubo we-latex ophinda uhlawulwe kuvumela ifilimu ye-polymer (ifilimu ye-latex) ukuba yenze kwaye yenze inxalenye yeendonga ze-pore, ngaloo ndlela itywina isakhiwo esinobukroti obukhulu bodaka. I-latex inwebu inomatshini wokuzolula okhupha uxinzelelo apho ibotshelelwe kudaka. Ngala mandla angaphakathi, udaka lugcinwa lulonke, ngaloo ndlela lukhulisa amandla adibeneyo odaka. Ubukho beepolymers eziguquguqukayo kakhulu kunye ne-elastic elasticity kuphucula ukuguquguquka kunye nokunwebeka kodaka.

Indlela yokunyuka koxinzelelo lwesivuno kunye namandla angaphumeleli ngolu hlobo lulandelayo: xa kusetyenziswe amandla, i-microcracks ibambezeleka kuze kube yilapho uxinzelelo oluphezulu lufikelelwa ngenxa yokuphucula ukuguquguquka kunye nokuqina. Ukongeza, imimandla yepolymer ephothiweyo iphinda ithintele ukudityaniswa kwee-microcracks kwiintanda ezigqobhozayo. Ngoko ke, i-polymer powder ehlaziywayo iphucula uxinzelelo lokungaphumeleli kunye nokungaphumeleli kwezinto eziphathekayo.

Ifilimu ye-polymer kwi-polymer modified mortar inefuthe elibaluleke kakhulu kwi-hard mortar. I-latex powder edibeneyo isasazwa kwi-interface idlala enye indima ebalulekileyo emva kokuchithwa kunye nokwenza ifilimu, oko kukwandisa ukunamathela kwizinto ezidibeneyo. Kwi-microstructure yepolymer yomgubo oguquliweyo wodaka lwethayile kunye nojongano lwethayile, ifilimu eyenziwe yipolymer yenza ibhulorho phakathi kweethayile ezine-vitrified kunye nokufunxwa kwamanzi aphantsi kakhulu kunye ne-matrix yodaka lwesamente. Indawo yoqhagamshelwano phakathi kwezinto ezimbini ezingafaniyo yindawo enobungozi kakhulu yokuqhekeka kweentanda kwaye kukhokelela ekulahlekeni kokubambisana. Ke ngoko, ukukwazi kweefilimu ze-latex ukuphilisa iintanda ze-shrinkage kubaluleke kakhulu kwi-adhesives tile.

Kwangaxeshanye, i-latex powder ephinda ihlaziywe equlethe i-ethylene inokunamathela okugqwesileyo kwi-organic substrates, ngakumbi izinto ezifanayo, ezifana ne-polyvinyl chloride kunye ne-polystyrene. Umzekelo omhle xa kufikwa kwiimaski.