Cellulose based materials have a range of material properties, that can be tweaked even further by the addition of additives to suit specific applications. With the goal to make thermally expandable microspheres (TEMS) of cellulose based materials, the additive is a vital component, that broadens the barrier- and softening properties. TEMS are developed under the trade name Expancel by Nouryon and are used as lightweight fillers and as blowing agents in various industrial fields such as paints, building materials, wine stoppers and many more. With our society increasingly focusing on sustainability, it would be an improvement to have the shell material cellulose based instead of fossil based. In this work, thin films of cellulose esters with various carboxylic acid additives were tested with XRD, SEM, DSC, contact angle, gas barrier performance, and directly in the application as TEMS with TGA, TMA and GC-FID. It was concluded that additives that work as hydrogen bond donors are well suited for the task and greatly enhance storage stability of the microspheres. The mechanism behind the hydrogen bond donor phenomenon is thought to be similar to a cross-linking, although less extensive since it is non-covalent. An additional unexpected benefit for the TEMS was the lack of toxic gases and ash during and after burning, which means that the product is also well suited as a sacrificial template, where well defined pores are required. The development of TEMS from cellulose based materials with hydrogen bond donor additives is ongoing and the first generation is on the market as a pilot scale product, named Expancel BIO 100. Going forward, the focus will be on collecting research and industrial input on the prototypes so that it can be developed in a way that is the most beneficial to society.