Preparation And Performance Of PVC Anti-pollution Membrane

The rules of different effects on PVC microfiltration membrane characteristic propertieswere sdudied in this paper. DMAc as solvent to formulate the casting solutions.PVC-0’sconcentration is10%which doesn’t contain additive.PVC-1,PVC-2and PVC-3blendmembrane that mixed with PVP,there concentrantion respectively are10%,12%and14%.Thecoagulation bath was35%DMAc, flat membrane were prepared by phase inversion.According to the results, the pore size distribution of PVC-0,PVC-1,PVC-2and PVC-3are0.120~0.172μm,0.117~0.213μm,0.125~0.173μm and0.086~0.103μm;There initialpressure when pores were blow open were248Kpa,202Kpa,250Kpa and410Kpa;Thereinitial contact angle were94.4~0、23.6~0、56.2~0�'�73.7~0；The average water flux in2minwere318L/h/100kPa/m~2,940L/h/100kPa/m~2,397L/h/100kPa/m~2and144L/h/100kPa/m~2,the average water flux in10min are257L/h/100kPa/m~2、680L/h/100kPa/m~2、295L/h/100kPa/m~2and72L/h/100kPa/m~2.The modification of grafting allyl polyethylene glycols (APEG) onto poly (vinyl chloride)(PVC) via atom transfer radical polymerization (ATRP) method was demonstrated. PVC wassolved in N,N-Dimethylacetamide (DMAc) and cuprous chloride (CuCl)/2,2’-dipyridine(BPy) acted as the catalyst system in the reaction. The properties of the modified polymerwere characterized by X-ray photoelectron spectroscopy (XPS) analysis, fourier transforminfrared spectrometry (FTIR) and1H NMR spectroscopy. These results indicated that APEGwas successfully grafted onto PVC. This modified polymer was used to form filtrationmembrane by phase-separation method. The SEM figures showed an asymmetric structurewith dense top layer and a finger-like macrovoid structure sub layer. The pore size range wasin0.117~0.247μm. Water contact angle on the membrane surface was decreased from81~oto64.4~oin300seconds. The initial pure water flux under0.05Mpa transmembrane pressurewas1677L/m~2h. The filtration of BSA solution went along for three cycles.The initial BSAsolution flux under0.05Mpa transmembrane pressure was737L/m~2h,it declined to steady101L/m~2h at the end of the three cycles.In addition,the article also discussed the affects of coagulation bath to PVC membrane-forming, the mothed to treatment the front surface cortex of PVC membrane.