Cov nyhuv ntawm Cellulose Ether ntawm Mortar Properties

Cov teebmeem ntawm ob hom cellulose ethers ntawm kev ua haujlwm ntawm mortar tau kawm. Cov txiaj ntsig tau pom tias ob hom cellulose ethers tuaj yeem txhim kho cov dej tuav ntawm mortar thiab txo qhov sib xws ntawm mortar; Lub zog compressive raug txo qis hauv qhov sib txawv, tab sis qhov sib piv folding thiab lub zog ntawm cov tshuaj khib nyiab tau nce ntau dua, yog li txhim kho kev tsim kho ntawm mortar.

Cov lus tseem ceeb:cellulose ether; dej tuav tus neeg sawv cev; kev sib raug zoo zog

Cellulose Ether (MC)yog ib tug derivative ntawm natural material cellulose. Cellulose ether tuaj yeem siv los ua tus neeg saib xyuas dej, thickener, binder, dispersant, stabilizer, suspending agent, emulsifier thiab film-forming aid, thiab lwm yam. Vim cellulose ether muaj cov dej tuav zoo thiab cov nyhuv thickening ntawm mortar, nws tuaj yeem txhim kho kev ua haujlwm zoo. ntawm mortar, yog li cellulose ether yog cov feem ntau siv dej-soluble polymer nyob rau hauv mortar.

1. Cov ntaub ntawv xeem thiab cov txheej txheem xeem

1.1 Cov khoom siv raw

Cement: Ordinary Portland cement tsim los ntawm Jiaozuo Jianjian Cement Co., Ltd., nrog qib zog ntawm 42.5. Xuab zeb: Nanyang daj xuab zeb, fineness modulus 2.75, nruab nrab xuab zeb. Cellulose ether (MC): C9101 ua los ntawm Beijing Luojian Company thiab HPMC ua los ntawm Shanghai Huiguang Company.

1.2 Test method

Nyob rau hauv txoj kev tshawb no, cov txiv qaub-xuab zeb piv yog 1: 2, thiab dej-cement piv yog 0.45; cov cellulose ether tau tov nrog cement ua ntej, thiab tom qab ntawd cov xuab zeb tau ntxiv thiab nplawm tusyees. Qhov ntau npaum ntawm cellulose ether yog xam raws li feem pua ​​​​ntawm cov cement loj.

Kev ntsuas lub zog compressive thiab kev ntsuas sib xws tau ua nrog kev siv rau JGJ 70-90 "Test Methods for Basic Properties of Building Mortar". Kev ntsuas lub zog flexural yog ua raws li GB / T 17671-1999 "Cement Mortar Strength Test".

Kev ntsuas dej tuav tau ua raws li cov ntawv lim dej siv hauv Fabkis aerated pob zeb ua lag luam. Cov txheej txheem tshwj xeeb yog raws li hauv qab no: (1) muab 5 txheej ntawm cov ntawv lim qeeb rau ntawm lub phaj yas, thiab ntsuas nws qhov hnyav; (2) muab ib qho kev sib cuag ncaj qha nrog lub mortar Muab cov ntawv lim dej ceev ceev rau ntawm daim ntawv lim dej qeeb, thiab tom qab ntawd nias lub tog raj kheej nrog ib txoj kab uas hla ntawm 56 hli thiab qhov siab ntawm 55 hli ntawm daim ntawv lim ceev; (3) Muab cov mortar rau hauv lub tog raj kheej; (4) Tom qab cov mortar thiab cov ntawv lim dej sib cuag rau 15 feeb, hnyav dua Qhov zoo ntawm cov ntawv lim qeeb thiab cov yas disc; (5) Xam cov dej loj absorbed los ntawm cov ntawv lim qeeb ib square meter cheeb tsam, uas yog tus nqi nqus dej; (6) Tus nqi nqus dej yog tus lej lej ntawm ob qhov kev xeem. Yog tias qhov sib txawv ntawm qhov ntsuas tus nqi siab tshaj 10%, qhov ntsuas yuav tsum tau rov ua dua; (7) Kev tuav dej ntawm lub mortar yog qhia los ntawm tus nqi nqus dej.

Qhov kev ntsuas lub zog tau ua tiav nrog kev siv rau txoj kev pom zoo los ntawm Nyiv Society for Materials Science, thiab daim ntawv cog lus lub zog yog tus cwj pwm los ntawm lub zog flexural. Qhov kev ntsuam xyuas tau txais cov qauv prism uas nws loj yog 160mm×40 mm×40 mm. Cov qauv mortar zoo tib yam ua ua ntej tau kho rau hnub nyoog 28 d, thiab tom qab ntawd txiav mus rau hauv ob halves. Ob qho tib si ntawm cov qauv tau muab tso rau hauv cov qauv nrog cov mortar zoo tib yam lossis polymer mortar, thiab tom qab ntawd kho tau zoo nyob hauv tsev rau qee lub hnub nyoog, thiab tom qab ntawd sim raws li txoj kev sim rau lub zog flexural ntawm cement mortar.

2. Cov txiaj ntsig thiab kev tshuaj xyuas

2.1 Kev sib raug zoo

Los ntawm cov nyhuv ntawm cellulose ether ntawm qhov sib xws ntawm mortar, nws tuaj yeem pom tau tias nrog kev nce ntawm cov ntsiab lus ntawm cellulose ether, qhov sib xws ntawm mortar yeej qhia tau hais tias kev poob qis, thiab qhov txo qis ntawm cov tshuaj khib nyiab sib xyaw nrog HPMC yog nrawm dua. tshaj li ntawm mortar tov nrog C9101. Qhov no yog vim qhov viscosity ntawm cellulose ether cuam tshuam qhov ntws ntawm mortar, thiab viscosity ntawm HPMC siab dua li ntawm C9101.

2.2 Kev tuav dej

Nyob rau hauv mortar, cementitious cov ntaub ntawv xws li cov cement thiab gypsum yuav tsum tau hydrated nrog dej thiaj li teem. Tus nqi tsim nyog ntawm cellulose ether tuaj yeem khaws cov dej noo nyob rau hauv mortar rau lub sijhawm ntev txaus, kom cov txheej txheem kev teeb tsa thiab tawv tawv tuaj yeem txuas ntxiv mus.

Los ntawm cov txiaj ntsig ntawm cellulose ether cov ntsiab lus ntawm cov dej khaws cia ntawm mortar, nws tuaj yeem pom tau tias: (1) Nrog rau qhov nce ntawm C9101 lossis HPMC cellulose ether cov ntsiab lus, cov dej nqus ntawm mortar txo qis, uas yog, cov dej tuav ntawm mortar tau zoo heev, tshwj xeeb tshaj yog thaum tov nrog Mortar ntawm HPMC. Nws cov dej tuav tau tuaj yeem txhim kho ntau dua; (2) Thaum tus nqi ntawm HPMC yog 0.05% mus rau 0.10%, lub mortar ua tau raws li qhov xav tau ntawm cov dej tuav hauv kev tsim kho.

Ob leeg cellulose ethers yog non-ionic polymers. Cov pab pawg hydroxyl ntawm cov cellulose ether molecular saw thiab cov pa atoms ntawm ether bonds tuaj yeem tsim hydrogen bonds nrog dej molecules, ua dej dawb rau hauv cov dej khi, yog li ua lub luag haujlwm zoo hauv dej tuav.

Cov dej tuav ntawm cellulose ether feem ntau yog nyob ntawm nws cov viscosity, particle loj, dissolution tus nqi thiab ntxiv tus nqi. Feem ntau, qhov ntau dua qhov ntxiv, qhov siab dua qhov viscosity, thiab qhov zoo dua qhov zoo, qhov dej tuav tau ntau dua. Ob leeg C9101 thiab HPMC cellulose ether muaj methoxy thiab hydroxypropoxy pawg nyob rau hauv cov saw molecular, tab sis cov ntsiab lus ntawm methoxy nyob rau hauv HPMC cellulose ether yog siab dua li ntawm C9101, thiab viscosity ntawm HPMC siab dua li ntawm C9101, yog li cov dej tuav ntawm mortar. tov nrog HPMC yog siab dua li ntawm mortar tov nrog HPMC C9101 loj mortar. Txawm li cas los xij, yog tias cov viscosity thiab cov txheeb ze molecular hnyav ntawm cellulose ether siab dhau lawm, nws cov solubility yuav txo qis raws li, uas yuav muaj kev cuam tshuam tsis zoo rau lub zog thiab kev ua haujlwm ntawm mortar. Lub zog muaj zog kom ua tiav cov txiaj ntsig zoo heev.

2.3 Flexural zog thiab compressive zog

Los ntawm cov nyhuv ntawm cellulose ether ntawm flexural thiab compressive lub zog ntawm mortar, nws tuaj yeem pom tau tias nrog kev nce ntawm cov ntsiab lus ntawm cellulose ether, flexural thiab compressive zog ntawm mortar ntawm 7 thiab 28 hnub pom qhov kev poob qis. Qhov no feem ntau yog vim: (1) Thaum cov cellulose ether ntxiv rau hauv mortar, cov polymers hloov tau yooj yim hauv qhov pores ntawm cov tshuaj khib nyiab tau nce, thiab cov polymers hloov tau yooj yim tsis tuaj yeem muab kev txhawb nqa nruj thaum cov khoom sib xyaw ua ke yog compressed. Yog li ntawd, lub flexural thiab compressive lub zog ntawm lub mortar yog txo; (2) Nrog rau qhov nce ntawm cov ntsiab lus ntawm cellulose ether, nws cov dej tuav cov nyhuv tau zoo dua thiab zoo dua, yog li tom qab cov tshuaj khib nyiab tau tsim, cov porosity hauv cov tshuaj khib nyiab nce ntxiv, lub zog flexural thiab compressive yuav raug txo. ; (3) Thaum cov mortar qhuav qhuav yog tov nrog dej, cov cellulose ether latex hais yog thawj zaug adsorbed rau saum npoo ntawm cov cement hais los ua ib zaj duab xis latex, uas txo cov dej ntawm cov cement, yog li txo lub zog ntawm cov cement. lub mortar.

2.4 Fold ratio

Qhov yooj ntawm lub mortar endows lub mortar nrog zoo deformability, uas ua rau nws hloov mus rau qhov kev ntxhov siab uas tsim los ntawm lub shrinkage thiab deformation ntawm lub substrate, yog li zoo heev txhim kho cov ntawv cog lus lub zog thiab durability ntawm lub mortar.

Los ntawm cov txiaj ntsig ntawm cellulose ether cov ntsiab lus ntawm mortar folding piv (ff / fo), nws tuaj yeem pom tau tias nrog kev nce ntawm cellulose ether C9101 thiab HPMC cov ntsiab lus, cov mortar folding piv tau qhia tias qhov kev hloov pauv ntawm mortar yog txhim kho.

Thaum cov cellulose ether yaj mus rau hauv mortar, vim hais tias cov methoxyl thiab hydroxypropoxyl ntawm cov saw molecular yuav hnov ​​​​mob nrog Ca2+ thiab Al3+ nyob rau hauv slurry, ib tug viscous gel yog tsim thiab sau nyob rau hauv lub cement mortar gap, yog li nws plays lub luag hauj lwm ntawm saj zawg zog filling. thiab hloov tau qhov cuab lub zog, txhim kho lub compactness ntawm lub mortar, thiab nws qhia tau hais tias qhov yooj ntawm cov hloov mortar yog txhim kho macroscopically.

2.5 Bond zog

Los ntawm cov txiaj ntsig ntawm cellulose ether cov ntsiab lus ntawm cov tshuaj khib nyiab lub zog, nws tuaj yeem pom tias cov ntawv cog lus lub zog nce ntxiv nrog cov ntsiab lus ntawm cellulose ether.

Qhov sib ntxiv ntawm cellulose ether tuaj yeem tsim ib txheej nyias ntawm cov ntaub ntawv tsis muaj dej tsis zoo ntawm cov cellulose ether thiab hydrated cement hais. Cov yeeb yaj kiab no muaj cov nyhuv sealing thiab txhim kho qhov "nto qhuav" tshwm sim ntawm mortar. Vim tias cov dej tuav tau zoo ntawm cellulose ether, cov dej txaus yog khaws cia rau hauv lub mortar, yog li ua kom cov hydration hardening ntawm cov cement thiab tag nrho txoj kev loj hlob ntawm nws lub zog, thiab txhim kho lub zog ntawm cov cement paste. Tsis tas li ntawd, qhov sib ntxiv ntawm cellulose ether txhim kho cov cohesion ntawm mortar, thiab ua rau lub mortar muaj zoo plasticity thiab yooj, uas kuj ua rau lub mortar zoo hloov mus rau lub shrinkage deformation ntawm lub substrate, yog li txhim kho lub zog ntawm lub mortar. .

2.6 Shrinkage

Nws tuaj yeem pom los ntawm cov txiaj ntsig ntawm cellulose ether cov ntsiab lus ntawm qhov shrinkage ntawm mortar: (1) Lub shrinkage tus nqi ntawm cellulose ether mortar yog qis dua li ntawm mortar dawb paug. (2) Nrog rau qhov nce ntawm C9101 cov ntsiab lus, lub shrinkage tus nqi ntawm mortar txo qis, tab sis thaum cov ntsiab lus mus txog 0.30%, tus nqi shrinkage ntawm mortar nce. Qhov no yog vim qhov ntau dua ntawm cov cellulose ether, qhov ntau dua nws cov viscosity, uas ua rau muaj kev xav tau dej ntau ntxiv. (3) Nrog rau qhov nce ntawm HPMC cov ntsiab lus, qhov shrinkage tus nqi ntawm mortar txo qis, tab sis thaum nws cov ntsiab lus mus txog 0.20%, qhov shrinkage nqi ntawm mortar nce thiab txo qis. Qhov no yog vim qhov viscosity ntawm HPMC ntau dua li ntawm C9101. Qhov siab dua qhov viscosity ntawm cellulose ether. Qhov dej tuav tau zoo dua, cov ntsiab lus huab cua ntau dua, thaum huab cua cov ntsiab lus nce mus txog ib theem, tus nqi shrinkage ntawm mortar yuav nce. Yog li ntawd, nyob rau hauv cov nqe lus ntawm shrinkage tus nqi, qhov zoo tshaj plaws npaum li cas ntawm C9101 yog 0.05% ~ 0.20%. Qhov zoo tshaj ntawm HPMC yog 0.05% ~ 0.10%.

3. Cov lus xaus

1. Cellulose ether tuaj yeem txhim kho cov dej tuav ntawm mortar thiab txo qhov sib xws ntawm mortar. Kho tus nqi ntawm cellulose ether tuaj yeem ua tau raws li cov kev xav tau ntawm cov tshuaj khib siv hauv cov haujlwm sib txawv.

2. Qhov sib ntxiv ntawm cellulose ether txo lub zog flexural thiab compressive lub zog ntawm lub mortar, tab sis ua rau kom cov folding piv thiab kev sib txuas lub zog rau qee yam, yog li txhim kho cov kav ntev ntawm cov mortar.

3. Qhov sib ntxiv ntawm cellulose ether tuaj yeem txhim kho qhov kev ua tau zoo ntawm cov mortar, thiab nrog kev nce ntawm nws cov ntsiab lus, cov nqi shrinkage ntawm mortar ua me thiab me. Tab sis thaum tus nqi ntawm cellulose ether nce mus txog ib theem, tus nqi shrinkage ntawm mortar nce mus rau ib qho twg vim qhov nce ntawm huab cua nkag mus.