Study On The Preparation And Performance Of The Transparent Regenerated Cellulose Film And Gel By Carbamate Method

With the requirements of green-sustainable development,the demand for green materials and quality requirements higher and higher,cellulose is one of an important green materials,storage capacity is very abundant in nature.Cellulose membranes and cellulose gel products become a hot research by the biodegradable cellulose-based advantages.At present,the composite membranes,and a cellulose-based gel products have been used in the separation of metals,harmful dye adsorption and the like.However,they are poor in transparency common,complicated preparation process,such as serious pollution drawbacks,at the same time,due to the large number of internal cellulose hydrogen bonds,resulting in difficult to dissolve cellulose,cellulose product development and application by a large extent.While improving the solubility of the cellulose,prepare a more transparent membrane material with a separation capability and the cellulose-based gels with adsorption capacity is very important.In this work,the cellulose pulp and urea as raw materials,using low-cost and environmentally friendly method of solid-phase synthetic cellulose carbamate(nitrogen content reached 4.5%),aqueous sodium hydroxide as the solvent preparation of regenerated cellulose membrane and regenerated cellulose transparent hydrogels by dissolving the cellulose carbamate.Regenerated cellulose carbamate solution formed in a coagulation bath,with high transparency and strong separation ability.Fourier transform infrared(FTIR)spectroscopy,X-ray diffraction(XRD)spectroscopy,Scanning electron microscopy(SEM)analysis and the thermogravimetric(TG)analysis to characterize analysis the membranes.The factors which influnce the transparent of membranes was discussed by orthogonal design and range analysis.Regenerated cellulose membrane interception capacity dyes were tested.The results show that the rejection of methylene blue and Congo red reached100%,retention of methyl orange reached 60%.Ability of separate oil/water of the regenerated cellulose membrane were tested which reached 100%,the effect of anti oil polution reached 97% can be reused many times.This membrane material may have a good prospect in terms of packaging materials,water treatment,biotechnology.Epichlorohydrin was join the cellulose carbamate solution as a crosslinking agent,to prepare a highly transparent regenerated cellulose hydrogel.Studies have shown thatregenerated cellulose hydrogel methylene blue adsorption rate reached 82.3%,the maximum amount of adsorption reached 207mg/g;Rhodamine B adsorption rate reached 75%,the maximum amount of adsorption reached 201.95mg/g,transparent and regenerated cellulose hydrogel having a strong adsorption capacity also has excellent mechanical properties,tensile strength at break and the compressive breaking strength of 4.25 Mpa and 8.82 Mpa,respectively.After the preparation of regenerated cellulose arogel average water absorption reached 1,997%,a swelling ratio of 64.37%.This green regenerated cellulose hydrogel and arogel will have wide application in the food,remove the dye and the like.