A process for preparing a polyaminoborane comprising reacting at least one monomer with an aminoborane, wherein the at least one monomer is selected from the group consisting of ammonia, a primary amine and a substituted or unsubstituted hydrazine; and wherein the aminoborane comprises a borane substituted by a secondary amino group; polyaminoboranes obtainable by said process; use of said polyaminoboranes for the preparation of a ceramic precursor or a ceramic, the production of boron nitride, or the storage and/or production of dihydrogen; ceramic precursors, ceramics, hydrogen cells or energy materials comprising said polyaminoboranes.