Conductive cellulose microfibrils and composites incorporating same

摘要

The cellulose microfibrils with an average length greater than 1 mu m, have an average diameter of 2-20 nm, forming factor of more than 60 of which the level of crystallisation is greater than 20%, preferably 70%, and are coated with a polypyrrole conducting film approximately 10-100 nm thick. Also claimed are: (i) a process for the preparation of dispersions of the claimed cellulose microfibrils; (ii) aqueous dispersion of the claimed cellulose microfibrils; (iii) aqueous compositions consisting of a latex polymer and the claimed cellulose microfibrils; (iv) compositions (X) comprising a matrix polymer and the claimed cellulose microfibrils; (v) films consisting of the claimed composition (X) and obtained by evaporation of a stable, aqueous composition of thermoplastic polymer and an aqueous suspension of the claimed cellulose microfibrils; (vi) powders consisting of the claimed composition (X) and obtained by the lyophilisation of an aqueous composition as in (v); (vii) films o f composition (X) and obtained by compressing powder as in (vi); (viii) sticks consisting of composition (X) made by extrusion of powder as in (vi); (ix) films consisting of composition (X) and obtained by compressing the extruded sticks as in (viii); and (x) plaques consisting of composition (X) and obtained by pressing the powder as in (vi) or the sticks as in (viii).