Application Of Bacterial Cellulose On Diaphragm For Loudspeaker

The properties relative to speaker diaphragm of bacterial cellulose were studied in this paper as well as process conditions of bacterial cellulose film formation and properties of modified bacterial cellulose. Feasibility of bacterial cellulose as paper additive improving properties of paper speaker diaphragm was investigated.Bacterial cellulose was a wet film formed on the vapor-liquid interface of culture medium. The wet film changed into a sheet like paper after drying. Through studying the static and dynamic mechanical properties of bacterial cellulose dry film under different conditions, the optimum process conditions of film formation were:culture time9d, concentration of alkali treatment3%, compression pressure1.6MPa, and vacuum drying.It was available to synthesize modified bacterial cellulose by adding water soluble polysaccharide (CMC and sodium alginate) into culture medium. Modified bacterial cellulose was better than common bacterial cellulose on both yield and mechanical properties. Besides bacterial cellulose modified by CMC obtained better properties compared to sodium alginate.After disintegrating, bacterial cellulose can be added into pulp to improve properties of paper speaker diaphragm. The optimum disintegrating revolution of bacterial cellulose wet film was60000and the optimum addition dose of bacterial cellulose fiber was8%. After that CMC was added to the pulp with8%bacterial cellulose fiber. The dynamic mechanical properties were better when CMC1%, but drainability of pulp got worse. At last drainability of pulp were improved by adding CPAM. The results showed that not only drainability of pulp was improved but also the dynamical elastic modulus was improved a bit.From the results of this paper, we can see that not only bacterial cellulose satisfies the properties demands for speaker diaphragm but also modified bacterial cellulose has higher yield and better properties. Besides, as paper additive bacterial cellulose fiber can improve properties of paper speaker diaphragm, which enlarges the application area of bacterial cellulose.