19083

۱۹۰۸۳

ساخت لايه الياف الكتروريسي شده آميخته سلولزاستات/پلي وينل آستات"اثر شبكه اي كردن و بخار حلال بر اندازه حفرات و عبور پذيري ذرات جامد معلق

كارشناسي ارشد

مهندسي شيمي - پليمر

۱۳۹۵

۱۳۹۷/۴/۲۳

دكتر محمد مقبلي

دكتر علي تهراني

مهندسي شيمي، نفت و گاز

1397/04/27

A FEASIBILITY STUDY ON THE EFFECT OF SOLVENT VAPOR TREATMENT AND CHEMICAL CROSSLINKING ON THE PORE SIZE AND FILTRATION ABILITIES OF CA/PVAC ELECTROSPUN MEMBRANE

7/18/2018 12:00:00 AM

Electrospun nanofibrous membranes are emerging materials in the filtration feild. However, the filtration efficiency differs from a membrane to another according to the conditions the membrane was subjected to. This thesis reports the synthesis, treatment and filtration characterization of cellulose acetate (CA) membranes for water filtration. After many attempts to produce a CA/PVAc electrospun membrane, the results always showed beaded and unsuccessful membranes. Therefore, only CA membranes were produced by electrospinning followed by solvent vapor treatment or chemical crosslinking. The solvent vapor treatment is basically subjecting the produced membrane to a flow of one of its solvents and it was done for different periods of time (30, 40 and 50) mins using acetone as a solvent.On the other hand, chemical crosslinking is the reaction between a crosslinker (TDI in our case) and a functional group (hydroxyl OH in our case) to produce a bridging between the groups. The chemical crosslinking treatment was done by two different methods. Characterizations such as SEM imaging, pore size analysis thickness and particle size analysis using (DLS) for filtration tests was done for all membranes and showed a deacrease in the average pore size up to 27.2% & 73.3% for solvent vapor and chemical crosslinking respectively as it also showed a change in the morphology of the membranes as well. Moreover, the filtration of polydispersed solid particles (kaolinite) showed an enhancemet by 18.1% & 23.15% for the suggested treatments which is consistent with the pore size results. Soaking the crosslinked membrane in its solvent (Acetone) showed a resistance against it, a result which was not seen in the case of the normal non-treated ones.