In this study, cellulose pulp and urea were used to synthesize cellulose carbamate (nitrogen content reaches 4.5%) by low-cost and environmentally friendly solid-liquid phase method. Cellulose carbamate fluid was prepared by using sodium hydroxide aqueous solution as solvent. The fluid was regenerated and formed in a coagulation bath , and finally a regenerated cellulose membrane with high transparency and separation ability was obtained. The simple chemical treatment of cellulose not only greatly increased the mass fraction of cellulose dissolution (It has reached 15%) and retains the original crystal form and thermal stability of cellulose. The surface of the membrane was relatively dense, and the inside has regular microchannel . The factors affect the transparency and water flux of regenerated cellulose membranes were discussed by orthogonal experimental range analysis. The ability of the regenerated cellulose membrane to reject dyes was tested. The results showed that the rejection of methyl blue and congo red reached 100%, and the rejection rate of methyl orange reached 60%. The oil/water separation ability and the anti-pollution ability of the regenerated cellulose membrane were tested. The oil/water separation effect reached 100%. This membrane may have application prospect in water treatment, biotechnology.
A novel polymer of intrinsic microporosity , acyl chloride-functionalized polymer of intrinsic microporosity (PIM-COCl), was obtained by hydrolysis under alkaline conditions and acylation in thionyl chloride of PIM-1. PIM-COCl is soluble in common organic solvents , and it is used for the first time for organic solvent nanofiltration (OSN). The acyl chloride groups in PIM-COCl can be further cross-linked with an amine-functionalized polyacrylonitrile (APAN) ultrafiltration membrane to form an interconnected layer, which shrinks pore size and provides better structural stability and selectivity. The PIM-COCl composite membranes exhibit high rejection and alcohol flux during OSN. Compared with the reported PIM OSN membranes , [email protected] exhibits higher rejection for crystal violet (408 g mol −1 , over 94%) in ethanol and several times higher alcohol flux. The membrane shows outstanding stability in ethanol for 14 days. PIM provides a microporous structure, while the interconnected layer maintains this structure in organic solvents via hydrogen bonding , electrostatic interactions and covalent cross-linking. Other PIMs can readily undergo acyl chloride functionalization, which provides them with high reactivity towards amine groups to form stable interconnected layers. This work offers new strategies for the design and preparation of high performance OSN membranes .
危险品化学品经营许可证（带存储）