Abstract    Hydrophobicity properties of graphite and green synthesized graphene (gsG) from exfoliated graphite/GO towards polymer membrane characteristic and properties at different weight percentage concentrations (1, 2, 3, 4 and 5 wt. %) were investigated. PSf/graphite and PSf/gsG membranes were characterized in term of hydrophobicity, surface bonding, surface roughness and porosity. FTIR peaks revealed that membrane with graphite and green synthesized graphene nearly diminished their O-H bonding which was opposite to the graphene oxide peak that show a strong O-H bonding as increased exfoliated time was reported in our previous work. These results were also in line with the contact angle results that showed strong hydrophobicity for the graphite and green synthesized graphene membranes which were then opposed to the exfoliated graphene oxide membrane that has strong affinity towards hydrophilicity properties (as mentioned in previous conducted works). The effect of strong hydrophobicity in modified membrane has result in smoother surface roughness compared to PSf membrane with exfoliated graphene oxide. Results of the surface roughness were in line with the FTIR transition peaks hydrophilicity of exfoliated graphene oxide. It showed that the transition peaks slowly reduced as increasing the formation of green synthesized graphene powder indicating the increment of hydrophobicity properties. The decreased of pure water flux was attributed to the decreased hydrophilicity. From the overall results, it is concluded that the hydrophobicity of PSf/graphite and PSf/green synthesized graphene membrane is not suitable to be applied in water separation whilst be potential for oil and dye separation.

Keywords    Graphite, Green synthesized graphene (gsG), PSf membrane, Hydrophobicity

چکیده    خواص آب گریزی گرافیت و اکسید گرافن کاهش یافته (rGO)(گرافیت ورقه/rGO ) به سمت غشاء PSf پلیمر مشخصه و خواص در غلظت وزن مکمل های مختلف 1) ، 2، 3، 4 و (wt. % 5 درصد وزنی مورد بررسی قرار گرفت. هر دو PSf/ گرافیت و غشاهای PSf/rGO در مدت آب گریزی، سطح اتصالی، زبری سطح و تخلخل مشخص شد. طیف FTIR نشان داد که غشاء با گرافیت و کاهش اکسید گرافن تقریبا کاهش پیوند OH خود را که در مقابل به اوج اکسید گرافن که نشان می دهد یک پیوند OH قوی به عنوان افزایش بار کندهشده بود. این نتایج در راستای نتایج زاویه تماس آبگریزی قوی از گرافیت و کاهش غشاء اکسید گرافن نشان داد به عنوان افزایش این غلظت مواد افزودنی. اثر آبگریزی قوی در این غشاها نیز در زبری سطح صاف در مقایسه با غشای PSf بکر منجر شده است. تحقیقات بیشتر از عملکرد جریان آب نیز ثابت کرد که هر دو غشا بالا اثر آبگریز قوی، با پایین ترین نرخ شار آب خالص (L/m2h) توسط ٪PSf/rGO 3 غشاء در 19.2437 L/m2h داده شد.

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