The objective of GASP is the development of 100% biobased polylactide materials including cellulose nanostructures with designed barrier properties for oxygen, CO2, water or organic vapors. These materials are targeted on high added value applications in the packaging industry. GASP is deliberately positioned on fully biobased and biodegradable commercially available polymers. It volunteers thereby to contribute to the solutions needed for developing sustainable growth of manufacturing industries by innovation and accompanying their transition versus the use of renewable resources. Organic polymers have already high market share in the packaging sector and their comparatively low gas and vapor barrier properties are one of the limitations to expansion towards novel applications in specialties. Precisely low barrier properties are also one of the major hurdles for novel biodegradable and biobased polymers entering the high volume market packaging. Nanostructures allow for tailoring material properties on the macromolecular scale and offer thus opportunity for development of innovative composites. Nanocelluloses are now available in industrial amounts and their high barrier properties to oxygen have already been shown. However, their potential is not exploited industrially today because industrial know-how for transformation with common plastics converters methodology is lacking. GASP tackles the two major hurdles for the fabrication of biobased barrier polymers, i) lack of scientific knowledge on the role of the nanofiller/polymer interfaces and ii) lack of plastics processing knowledge for the creation of performing polymer composites. GASP proposes the following strategy: On the molecular scale, GASP aims to develop nanocellulose surface grafting processes for tailoring the nanocellulose/polymer interface with two goals i) compatibilizing both partners and ii) engineering the interfaces by grafting of nanocellulose surfaces with molecules able to selectively trap permeants for improving barrier properties. On the processing scale, GASP seeks to develop nanocellulose processing techniques in the aim to create optimized material architectures. For that goal a simulation driven approach will also be used to define the most appropriate architectures for improved barrier properties. To rise to this challenge a highly competitive consortium of industrial and academic actors has joined. Leading French academic laboratories in polymer processing (PIMM), gas barrier properties of nanocomposites and modeling (IMP), diffusion/solubility properties of polymers (PBS), food/polymer interactions (GENIAL), surface chemistry (ICMMO) and characterization and modification of nanocelluloses (LGP2) will work hand in hand with two start ups in creation of specific molecular traps (Ajelys) and production of tailor-made nanocelluloses (Inofib), and two companies specialized in thermoforming of food containers (CGL Pack) and film fabrication and complexing (Wipak). The outcomes of GASP will be on the academic level advancing the state of the art of our common knowledge on transport properties and mechanisms on very localized interfaces between nanostructures and polymers. The scientific results will be brought to a large community of users by communication in scientific congresses and teaching actions, professional events and science communication to public. On the industrial level, GASP aims on the creation of two pilot materials able to be transferred to industrial pilot scale processes and directly impacting the business of the associated companies. For the consumer GASP will pave the way towards renewable packaging materials complying with the highest standards of performance and safety.