Focus on Cellulose ethers

IiPropati zoomatshini be-Etere yeCellulose iLungiselelwe udaka lwesamente

IiPropathi zoomatshini be-Etere yeSelulosi iLungiselelwe Udaka lwesamente

Udaka lwesamente olulungisiweyo kunye nomlinganiselo wamanzi-samente ka-0.45, umlinganiselo we-lime-sand ye-1: 2.5, kunye ne-cellulose ether ene-viscosities eyahlukeneyo ye-0%, 0.2%, 0.4%, 0.6%, 0.8%, kunye ne-1.0% yalungiswa. . Ngokulinganisa iipropathi zemishini yodaka lwesamente kunye nokujonga i-morphology ye-microscopic, umphumo we-HEMC kumandla oxinzelelo, amandla e-flexural kunye namandla ebhondi yodaka lwesamente olulungisiweyo lwafundwa. Iziphumo zophando zibonisa ukuba: ngokunyuka komxholo we-HEMC, amandla oxinzelelo omdaka oguquliweyo kwiminyaka eyahlukeneyo ayancipha ngokuqhubekayo, kwaye uluhlu lokunciphisa luyancipha kwaye luvame ukuba mnene; xa umxholo ofanayo we-cellulose ether wongezwa, Amandla oxinzelelo lwe-cellulose ether udaka olulungisiweyo olune-viscosities ezahlukeneyo ngu: HEMC20 HEMC10>HEMC5.

Amagama angundoqo:i-cellulose ether; udaka lwesamente; amandla oxinzelelo; amandla okuguquguquka; amandla bond

 

1. Intshayelelo

Kweli nqanaba, imfuno yonyaka yodaka emhlabeni idlula iitoni ezingama-200 ezigidi, kwaye imfuno yemizi-mveliso isakhula. Okwangoku, udaka lwesamente lwemveli luneziphene ezinjengokopha, i-delamination, i-shrinkage enkulu yokomisa, ukunganyangeki, ukunganyangeki, amandla ebhondi ephantsi, kunye ne-hydration engagqibekanga ngenxa yokulahleka kwamanzi, ekunzima ukuyicombulula, kungekuphela nje ukubangela iziphene zokwakha, kodwa kunye nokukhokela. ukwenza ukuqina kwePhenomena njengokuqhekeka kodaka, ukucolwa, ukuphalazwa, kunye nokugrunjwa.

Njengenye yeendlela eziqhelekileyo ezisetyenziselwa udaka lwezorhwebo, i-ether ye-cellulose inemisebenzi yokugcinwa kwamanzi, ukuqina kunye nokunciphisa, kwaye ingasetyenziselwa ukuphucula iimpawu ezibonakalayo zodaka lwesamente ezifana nokusebenza, ukugcinwa kwamanzi, ukusebenza kwebhondi, kunye nexesha lokubeka. , njengokwandisa kakhulu isamente. Amandla ebhondi eqinile yodaka aya kuncitshiswa, kodwa amandla acinezelayo, amandla okuguquguquka kunye nemodyuli enwebekayo yodaka lwesamente iya kuncitshiswa. UZhang Yishun kunye nabanye bafunde umphumo we-methyl cellulose ether kunye ne-hydroxypropyl methyl cellulose ether kwiipropati zodaka. Iziphumo zibonise ukuba: zombini i-cellulose ethers inokuphucula ukugcinwa kwamanzi kwi-mortar, kunye namandla okuguquguqukayo kunye namandla oxinzelelo ayancipha kwiidigri ezahlukeneyo, ngelixa umlinganiselo wokugoba kunye namandla okubambisana okunyuka kodaka kwiidigri ezahlukeneyo, kunye nokusebenza kwe-shrinkage yodaka luyakwazi. iphuculwe. AJenni, R. Zurbriggen, njl.njl. basebenzise iindlela zangoku zovavanyo kunye nohlalutyo lokufunda ukusebenzisana kwezixhobo ezahlukeneyo kwi-cellulose ether eguqulweyo yenkqubo yodaka encamathelayo encamathelayo, kwaye yabona ukuba i-cellulose ether kunye ne-Ca(OH) zivele kufutshane nomphezulu wodaka. . 2, ebonisa ukufuduka kwe-cellulose ethers kwizinto ezisekelwe kwi-samente.

Kweli phepha, kusetyenziswa iindlela zovavanyo lodaka ezifana nokumelana noxinzelelo, ukuxhathisa ukuguquguquka, ukudibanisa, kunye nenkangeleko ye-SEM encinci, impembelelo ye-cellulose ether isamente yodaka kwiipropathi zoomatshini ezinje ngokuqina koxinzelelo, ukuchasana nokuguquguquka, kunye namandla ebhondi kwiminyaka eyahlukeneyo iyafundwa, kwaye iyacaciswa. indlela yokusebenza kwayo.

 

2. Imathiriyeli ekrwada kunye neendlela zokuvavanya

2.1 Iimathiriyeli ekrwada

2.1.1 Isamente

I-samente ye-laurate eqhelekileyo eveliswe ngu-Wuhan Huaxin Cement Co., Ltd., imodeli ye-P 042.5 (GB175-2007), inoxinano lwe-3.25g / cm³ kunye nommandla othile we-4200cm²/g.

2.1.2 I-Hydroxypropyl methylcellulose ether

Iihydroxyethyl methyl cellulose ethereveliswe yiHercules Group yaseUnited States ine-viscosities ye-50000MPa / s, i-100000MPa / s, kunye ne-200000MPa / s kwi-2% isisombululo kwi-25°C, kwaye ezi zishunqulelo zilandelayo HEMC5, HEMC10, kunye HEMC20.

2.2 Indlela yokuvavanya

a. Amandla acinezelayo odaka olulungisiweyo

Ukunyanzeliswa kwamandla okulinganisa umzimba ohlaza kwavavanywa nge-TYE-300 umatshini wamandla oxinzelelo ovela kwi-Wuxi Jianyi Instrument Co., Ltd. Umlinganiselo wokulayisha ngu-0.5 kN / s. Uvavanyo lwamandla oxinzelelo lwenziwa ngokwe-GB/T17671-1999 "Indlela yoVavanyo lwamandla e-Cement Mortar (Indlela ye-ISO)".

Ngengcaciso, ifomula yokubala amandla oxinzelelo lomzimba oluhlaza yile:

Rc=F/S

Apho uRc-amandla oxinzelelo, iMPa;

F-ukusilela komthwalo osebenza kumzekelo, kN;

S-indawo yoxinzelelo, m².

Ngenkcazo, ifomula yokubala amandla aguquguqukayo omzimba oluhlaza yile:

Rf= (3P× L)/(2b× h²) =0.234×P

Kwifomula, Rf-amandla okuguquguquka, MPa;

P-ukusilela komthwalo osebenza kumzekelo, kN;

L-umgama phakathi kwamaziko okuxhasa iisilinda, oko kukuthi, i-10cm;

b, h-ububanzi kunye nokuphakama kwecandelo elinqamlezayo lomzimba wokuvavanya, zombini ziyi-4cm.

b. Ukuqina kwebhondi yodaka lwesamente olulungisiweyo

Sebenzisa i-ZQS6-2000 i-Adhesive Brick Adhesive Strength Detector ukulinganisa amandla okubambelela, kunye nesantya sokuqina ngu-2mm / min. Uvavanyo lwamandla okudibanisa luqhutywe ngokwe-JC/T985-2005 "i-Cement-based self-leveling mortar for ground".

Ngenkcazo, ifomula yokubala amandla ebhondi yomzimba oluhlaza yile:

P=F/S

Kwifomula, uP-ukomelela kokuqina kwebhondi, iMPa;

F-ubukhulu bokusilela komthwalo, N;

S-indawo yokudibanisa, mm².

 

3. Iziphumo kunye nengxoxo

3.1 Amandla acinezelayo

Ukususela kumandla oxinzelelo lweentlobo ezimbini ze-cellulose ether eziguquguqukayo zodaka kunye ne-viscosities eyahlukeneyo kwiminyaka eyahlukeneyo, kunokubonwa ukuba ngokunyuka komxholo we-HEMC, amandla oxinzelelo lwe-cellulose ether eguquguqukayo yodaka kwiminyaka eyahlukeneyo (3d, 7d kunye ne-28d) yehla. ngokubalulekileyo. Ukunciphisa ngokuphawulekayo kwaye ngokuthe ngcembe kuzinzile: xa umxholo we-HEMC wawungaphantsi kwe-0.4%, amandla oxinzelelo ayancipha kakhulu xa kuthelekiswa nesampuli engenanto; xa umxholo we-HEMC wawuyi-0.4% ~ 1.0%, umkhwa wokunciphisa amandla oxinzelelo wehla. Xa umxholo we-cellulose ether mkhulu kune-0.8%, amandla oxinzelelo lwe-7d kunye ne-28d yobudala bungaphantsi kunesampulu engenanto kwi-3d yobudala, ngelixa amandla oxinzelelo odaka olulungisiweyo lwe-3d luphantse lube zero, kwaye isampuli icinezelwe kancinci Ngokukhawuleza ityunyuzwe, ingaphakathi liyimpuphu, kwaye ubuninzi buphantsi kakhulu.

Impembelelo ye-HEMC efanayo kumandla oxinzelelo lodaka oluguquliweyo kwiminyaka eyahlukeneyo ikwahluke, ibonisa ukuba amandla oxinzelelo lwe-28d ayancipha ngokunyuka komxholo we-HEMC ngaphezu kwe-7d kunye ne-3d. Oku kubonisa ukuba umphumo wokunciphisa i-HEMC uhlala ukhona ngokunyuka kweminyaka, kwaye umphumo wokunciphisa i-HEMC awuzange uchaphazeleke ngokunciphisa amanzi kwinkqubo okanye inkqubela phambili ye-hydration reaction, okubangelwa ukukhula kwamandla oxinzelelo. yodaka olulungisiweyo luncinci kakhulu kunolo ngaphandle kweesampulu zeMortar ezixutywe neHEMC.

Ukusuka kwijiko lokutshintsha lamandla oxinzelelo lwe-cellulose ether udaka oluguquliweyo kwiminyaka eyahlukeneyo, kunokubonwa ukuba xa umlinganiselo ofanayo we-cellulose ether yongezwa, amandla oxinzelelo lwe-cellulose ether udaka oluguquliweyo olune-viscosities eyahlukeneyo yile: HEMC20 HEMC10>HEMC5. Oku kungenxa yokuba i-HEMC enezinga eliphezulu le-polymerization inempembelelo enkulu ekunciphiseni amandla oxinzelelo lodaka kune-HEMC eneqondo eliphantsi le-polymerization, kodwa amandla okunyanzeliswa kodaka olulungisiweyo oluxutywe kunye ne-HEMC luphantsi kakhulu kunolo lwe-polymerization. udaka olungenanto ngaphandle kwe-HEMC.

Ezi zinto zintathu zilandelayo zikhokelela ekunciphiseni amandla oxinzelelo odaka olutshintshiweyo: kwelinye icala, ngenxa yokuba i-HEMC enyibilikayo yamanzi isakhiwo se-macromolecular network sigubungela amasuntswana e-samente, i-CSH gel, i-calcium oxide, i-calcium aluminate hydrate kunye namanye amasuntswana kunye ne-unhydrated. amasuntswana Kwi-surface, ngakumbi kwinqanaba lokuqala le-cement hydration, i-adsorption phakathi kwe-calcium aluminate hydrate kunye ne-HEMC inciphisa ukusabela kwe-hydration ye-calcium aluminate, okubangelwa ukuhla okukhulu kwamandla oxinzelelo. Umphumo wokunciphisa umdaka osisigxina uyabonakala, obonisa ukuba xa umxholo we-HEMC20 ufikelela kwi-0.8% ~ 1%, amandla e-3d yesampuli yodaka olulungisiweyo luyi-zero; Ngakolunye uhlangothi, isisombululo se-HEMC esine-hydrated sine-viscosity ephezulu, kwaye Ngexesha lokuxuba udaka, inokuxutywa nomoya ukuze yenze inani elikhulu leebhubhu zomoya, okubangelwa inani elikhulu le-voids kumdaka olukhuni. , kwaye amandla oxinzelelo lwesampulu ayancipha ngokuqhubekayo ngokunyuka komxholo we-HEMC kunye nokunyuka kwe-polymerization degree; Inkqubo yodaka yandisa kuphela ukuguquguquka kodaka kwaye ayikwazi ukudlala indima yenkxaso eqinile, ngoko ke amandla oxinzelelo ayancipha.

3.2 Amandla e-Flexural

Ukususela kumandla we-flexural we-viscosity viscosity cellulose i-ether eguqulelwe ii-mortars eziguquguqukayo kwiminyaka eyahlukeneyo, kunokubonwa ukuba kufana nokutshintsha kwamandla oxinzelelo lodaka oluguquliweyo, amandla okuguquguquka kwe-cellulose ether udaka olutshintshiweyo luyancipha ngokuthe ngcembe ngokunyuka komxholo we-HEMC.

Ukususela kwijika eliguqukayo lamandla e-flexural ye-cellulose ether eguquguqukayo udaka kwiminyaka eyahlukeneyo, kunokubonwa ukuba xa umxholo we-cellulose ether ufana, amandla e-flexural ye-HEMC20 isampuli yodaka eguquliweyo ingaphantsi kancinane kune-HEMC10 isampuli yodaka olulungisiweyo, ngelixa Xa umxholo we-HEMC u-0.4% ~ 0.8%, i-28d amandla e-flexural change curves of the two phantse ihambelana.

Ukususela kwijika eliguqukayo lamandla e-flexural ye-cellulose ether eguquliweyo udaka kwiminyaka eyahlukeneyo, kunokubonwa ukuba utshintsho lwamandla aguquguqukayo odaka olulungisiweyo: HEMC5

3.3 Amandla ebhondi

Ingabonwa ukusuka kwiigophe eziguquguqukayo zamandla ebhondi ye-cellulose ether eguqulwayo yodaka olutshintshiweyo kwiminyaka eyahlukeneyo ukuba amandla ebhondi yodaka olulungisiweyo ayanda ngokunyuka komxholo we-HEMC kwaye ngokuthe ngcembe athande ukuzinza. Ngokwandiswa kweminyaka, amandla ebhondi yodaka oluguquliweyo nawo abonise indlela eyandayo.

Inokubonwa ukusuka kwi-28-day bond bond change curves of the three cellulose ether modified mortars that the bond bond of the modified mortar ukwanda kunye nokunyuka komxholo we-HEMC, kwaye ngokuthe ngcembe idla ngokuzinza. Ngexesha elifanayo, ngokunyuka kweqondo le-polymerization ye-cellulose ether, utshintsho lwamandla ebhondi yodaka olulungisiweyo: HEMC20>HEMC10>HEMC5.

Oku kubangelwa ukuqaliswa kwenani elikhulu leepores kumdaka otshintshiweyo kunye nomxholo ophezulu we-HEMC, okubangelwa ukwanda kwe-porosity yomzimba onzima, ukuncipha kobuninzi besakhiwo, kunye nokukhula okucothayo kwamandla ebhondi. ; kuvavanyo lwe-tensile, ukwaphuka kwenzeka kudaka olulungisiweyo Ngaphakathi, akukho kwaphuka kwindawo yokudibanisa phakathi kodaka olulungisiweyo kunye ne-substrate, ebonisa ukuba amandla ebhondi phakathi kodaka oluguquliweyo kunye ne-substrate inkulu kunelo lukhuni. udaka olulungisiweyo. Nangona kunjalo, xa inani le-HEMC liphantsi (0% ~ 0.4%), ii-molecule ze-HEMC ezinyibilikayo zamanzi ziyakwazi ukugubungela kunye nokugubungela kwiinqununu ze-cement ze-hydrated, kwaye zenze ifilimu ye-polymer phakathi kweengqungquthela ze-samente, okwandisa ukuguquguquka kunye nokuguquguquka udaka olulungisiweyo. I-Plastiki, kwaye ngenxa yokugcinwa kwamanzi okugqwesileyo kwe-HEMC, udaka olulungisiweyo lunamanzi aneleyo okuphendula i-hydration, okuqinisekisa ukuphuhliswa kwamandla e-samente, kwaye amandla ebhondi yodaka lwesamente oluguquliweyo lwanda ngokulandelelana.

3.4 SEM

Ukususela kwimifanekiso ye-SEM yokuthelekisa ngaphambi nangemva kokuba i-cellulose ether iguqulwe udaka, kunokubonwa ukuba izikhewu phakathi kweenkozo ze-crystal kwi-mortar engaguqukiyo zinkulu, kwaye inani elincinci leekristale zenziwa. Kumdaka oguquliweyo, iikristale zikhula ngokupheleleyo, ukufakwa kwe-cellulose ether kuphucula ukusebenza kokugcinwa kwamanzi omdaka, i-samente igcwele i-hydrated, kwaye iimveliso ze-hydration ziyabonakala.

Oku kungenxa yokuba i-ether ye-cellulose iphathwe ngenkqubo ekhethekileyo ye-etherification, enokusasazwa okugqwesileyo kunye nokugcinwa kwamanzi. Amanzi akhululwa ngokuthe ngcembe kwixesha elide, kuphela umlinganiselo omncinci wamanzi ophuma kwi-capillary pores ngenxa yokomisa kunye nokuphuma komphunga, kwaye amaninzi amanzi ahlanjululwa ngesamente ukuqinisekisa amandla odaka lwesamente olulungisiweyo.

 

4 Isiphelo

a. Njengoko umxholo we-HEMC ukhula, amandla okunyanzeliswa komdaka oguquliweyo kwiminyaka eyahlukeneyo ayancipha ngokuqhubekayo, kwaye uluhlu lokunciphisa luyancipha kwaye luvame ukuba tyaba; xa umxholo we-cellulose ether mkhulu kune-0.8%, i-7d kunye ne-28d Amandla oxinzelelo lwesampula engenanto ye-3d yobudala iphantsi kunesampulu engenanto, ngelixa i-3d-ubudala obunamandla obuxinzelelekileyo bodaka oluguquliweyo luphantse lube zero. Isampulu iyaphuka xa icinezelwe kancinci, kwaye ingaphakathi liyimpuphu kunye noxinzelelo oluphantsi.

b. Xa umlinganiselo ofanayo we-cellulose ether yongezwa, amandla oxinzelelo lwe-cellulose ether udaka olulungisiweyo olunee-viscosities ezahlukeneyo lutshintsha ngolu hlobo lulandelayo: HEMC20 HEMC10>HEMC5.

c. Amandla e-flexural ye-cellulose ether eguqulwayo yodaka iyancipha ngokuthe ngcembe ngokunyuka komxholo we-HEMC. Ukutshintsha kwamandla okuguquguquka kodaka olulungisiweyo: HEMC5

d. Amandla okubopha udaka olulungisiweyo ayanda ngokunyuka komxholo we-HEMC, kwaye ngokuthe ngcembe kudla ngokuzinza. Ngexesha elifanayo, ngokunyuka kweqondo le-polymerization ye-cellulose ether, utshintsho lwamandla ebhondi yodaka olulungisiweyo: HEMC20>HEMC10>HEMC5.

e. Emva kokuba i-ether ye-cellulose ixutywe kwi-cement mortar, i-crystal ikhula ngokupheleleyo, i-pores phakathi kwe-crystal grains iyancitshiswa, kwaye i-samente igcwele i-hydrated ngokupheleleyo, eqinisekisa ukunyanzeliswa, ukuguquguquka kunye namandla okudibanisa kwe-cement mortar.

 


Ixesha lokuposa: Jan-30-2023
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