Spinning Study Of Modified Phenolic Fibers

Phenolic fiber is a three-dimensional network structure of phenol and formaldehyde by addition and polycondensation of special fiber,is an amorphous,non-oriented body structure polymer.Phenolic fiber belongs to intrinsic flame retardant fiber and has good self-flame retardancy.Phenolic fiber has the characteristics of high residual carbon rate and excellent flame retardant performance.Phenolic fiber only contains three elements,C,H,O,which can have a high carbon yield in the process of preparing phenolic active carbon fiber.Phenolic-based active carbon fiber has the characteristics of excellent adsorption performance,large specific surface area,and simple green preparation process,so it has greater development potential in the preparation of high adsorption materials.Phenolic fiber and phenolic activated carbon fiber have broad application prospects in personal protection,transportation and aerospace and other fields.However,phenolic fiber production is difficult,the price is high,and the spinning is difficult,so that phenolic fiber is less used in real life.Therefore,optimizing the mechanical properties of phenolic fibers and their spinning process,improving production efficiency,and studying carbonization and activation processes to prepare phenolic active carbon fibers with excellent adsorption performance have become the focus of research.In this paper,phosphorus(P)was used to improve the performance of phenolic fibers,and phosphorus-modified phenolic fibers were prepared by changing the ratio of raw materials during the synthesis process,and then carbonization and activation were carried out to prepare phosphorus-modified phenolic-based activated carbon fibers.(1)In the synthesis process,the effects of different synthesis conditions on fiber properties were studied by changing the molar ratio of phenol and formaldehyde,PVA mass fraction and modifier content in the synthetic raw materials,and the results showed that when the molar ratio of phenol to formaldehyde was 1:1.5,the mass fraction of PVA was 7%,and the content of modifier was 6%,the mechanical properties of the fiber were the best,the elongation at break was 8.84%,the breaking strength was 217.1MPa,the heat resistance was also good,and the fiber residual carbon rate was 53.7%.(2)In the wet spinning process,the effect of different spinning processes on fiber properties was studied by changing the number of holes in the spinneret cap and the type of oiling agent,and the results showed that increasing the number of holes on the spinneret cap in the wet spinning process,from 1 hole to 3 holes,5 holes to 20 holes,the spinning amount of phenolic fiber per unit time was improved,and the mechanical properties of the fiber were improved.Different oils A and B were used to oil the porous fibers,and after the oil A treatment,the fibers stuck together were separated,and the compliance of the fibers was also improved.(3)The modified phenolic fibers with the best performance prepared by wet spinning were carbonized and activated,and the modified phenolic active carbon fibers were prepared,and the effects of various factors on phenolic active carbon fibers were studied by changing the carbonization temperature,activation temperature and activation time.The results show that phosphorus-modified phenolic activated carbon fibers with a carbonization temperature of 800°C,an activation temperature of 700°C,and an activation time of 0.5h have the best performance.Its specific surface area can reach 595.27m~2/g,and the adsorption performance of methylene blue and iodine is also the best,and the adsorption value can reach 330.72mg/g and 1809.67mg/g.