Umlando Wokuthuthukiswa Kwempushana Ehlakazeka Kabusha

I-Redispersible powder (RDP) iwuhlobo lwempushana ye-polymer esetshenziswa embonini yezokwakha njengesengezo emikhiqizweni esekwe usimende njengodaka, ama-grouts, nezinhlanganisela zokuzilinganisa. Ama-RDP aqala ukuthuthukiswa ngeminyaka yawo-1950s futhi asebeyingxenye ebalulekile ezintweni zokwakha zesimanje. Kulesi sihloko, sizobheka kabanzi umlando wokuthuthukiswa kwe-RDP nokubaluleka kwayo embonini yezokwakha.

Iminyaka yokuqala

Ama-RDP okuqala athuthukiswa ngeminyaka yawo-1950 yinkampani yaseJalimane ebizwa ngokuthi i-Wacker Chemie AG. Ngaleso sikhathi, i-Wacker Chemie AG yayenza izinto ezintsha zokwenziwa ukuze kuhlangatshezwane nezidingo ezikhulayo zokuthuthukiswa kokwakhiwa kwangemva kwempi. Babefuna indlela yokuthuthukisa izakhiwo zezinto ezenziwe usimende, njengokumelana namanzi, ukuqina, kanye nokuguquguquka.

Ezinsukwini zokuqala, ama-RDPs akhiqizwa ngokuncibilikisa i-polyvinyl acetate (PVA) ku-solvent bese efafaza isixazululo ekamelweni elishisayo lapho i-solvent izohwamuka, ishiye impushana enhle. Le mpushana ingahlakazwa kalula emanzini futhi isetshenziswe njengesengezo emikhiqizweni esekwe usimende.

Kodwa-ke, bekunemikhawulo ethile kulolu hlobo lokuqala lwe-RDP. Isibonelo, kwakunzima ukulawula usayizi wezinhlayiyana kanye nokuma kwempushana, okungathinta ukusebenza kwayo emikhiqizweni esekwe usimende. Ngaphezu kwalokho, impushana yayingazinzile kakhulu futhi yayivame ukwenza izigaxa noma izigaxa, okwenza kube nzima ukuphatha nokusebenzisa.

Ukuthuthukiswa nokuqanjwa kabusha

Ngokuhamba kweminyaka, abacwaningi nonjiniyela benze intuthuko enkulu enqubweni yokukhiqiza nezakhiwo zama-RDP. Isibonelo, ukuthuthuka kwe-polymer chemistry kuholele ekuthuthukisweni kwama-polymers amasha anikeza ukusebenza okuthuthukisiwe nokuzinza.

Enye yentuthuko ebaluleke kakhulu kubuchwepheshe be-RDP yafika ngeminyaka yawo-1980 ngokwethula inqubo entsha yokukhiqiza ebizwa ngokuthi ukomiswa kwesifutho. Le nqubo ihilela ukufafaza i-emulsion ye-polymer ekamelweni elishisayo lapho amanzi ehwamuka khona, eshiya impushana enhle. Le ndlela yavumela ukulawula okukhulu phezu kosayizi wezinhlayiyana kanye nokuma kwe-powder, okuholela ekusebenzeni okungaguquki futhi okubikezelwe emikhiqizweni esekwe usimende.

Enye into entsha kubuchwepheshe be-RDP beza nokwethulwa kwe-latex powder (RPL), eyenziwe nge-latex emulsion esikhundleni se-PVA. Ama-RPL anikeza ukumelana nokunamathela kwamanzi okuthuthukisiwe uma kuqhathaniswa nama-RDP asekelwe ku-PVA, okuwenza abe yinketho edumile yezinhlelo zokusebenza zangaphandle ezifana ne-stucco ne-EIFS (i-insulation yangaphandle kanye nohlelo lokuqedela).

Izicelo kanye nezinzuzo

Ama-RDP ahlinzeka ngenani lezinzuzo embonini yezokwakha, okuhlanganisa ukusebenza okuthuthukisiwe, ukunamathela, nokumelana namanzi. Angasetshenziswa emikhiqizweni eminingi esekwe usimende, okuhlanganisa udaka, ama-grouts, ama-self-leveling compounds, nama-adhesives amathayili.

Enye yezinzuzo ezibalulekile zama-RDP yikhono lawo lokuthuthukisa ukusebenza kanye nokusebenziseka kalula kwemikhiqizo esekwe usimende. Bangakwazi ukunciphisa inani lamanzi adingekayo ukuze kuzuzwe ukuvumelana okufunayo, okungathuthukisa amandla nokuqina komkhiqizo ophelile. Zingasiza futhi ekwehliseni ukuqhekeka kanye nokuncipha, okungenzeka uma imikhiqizo eyenziwe usimende yoma ngokushesha kakhulu.

Ngaphezu kwalokho, ama-RDP angathuthukisa ukunamathela kwemikhiqizo esekwe usimende kuma-substrates ahlukahlukene, okuhlanganisa ukhuni, insimbi, kanye namatshe. Angaphinda athuthukise ukumelana namanzi kanye nokuqina kwemikhiqizo eyenziwe usimende, iyenze ibe ilungele ukusetshenziswa ezindaweni ezimanzi noma ezindaweni ezingaphansi kwethrafikhi ephezulu noma umthelela.

Isiphetho

Sengiphetha, umlando wokuthuthuka we-RDP umakwe ngenqubekelaphambili ebalulekile kumakhemikhali e-polymer kanye nezinqubo zokukhiqiza. Kusukela ekuqaleni kwawo-1950s, i-RDP isiyingxenye ebalulekile ezintweni zokwakha zesimanje, enikeza izinzuzo eziningi ngokuya ngokusebenza, ukunamathela.