H2020 BARBARA Project: Biopolymers with advanced functionalities for construction and automotive parts processed through additive manufacturing

BARBARA partners extracted and characterized functional additives from lemon and pomegranate agricultural waste, sourced from fruit waste discarded by Spanish farmers and supplied by FECOAM. The UA team developed and optimized laboratory-scale microwave-assisted extraction (MAE) protocols for lemon and pomegranate agricultural waste using multivariate experimental designs. These protocols enabled the extraction of lemon essential oil, pigments (lemon and pomegranate), and pomegranate biomordants (tannins and other polyphenols), as well as their functionalization and design for use as polymer additives. CELABOR was responsible for the purification and scale-up of the active additives.

The optimization of broccoli chlorophyll extraction at laboratory scale using MAE was also carried out by the UA (with support from UNIPG). Seven additives with coloring, aromatic, antimicrobial, or biomordant functions were obtained from the agricultural waste studied in the work carried out by the UA and CELABOR partners: lemon essential oil; lemon yellow pigment; pomegranate pigments and antibacterial pomegranate biomordant; broccoli green pigment; and almond antimicrobial extract and strengthening additive.

Regarding the development of engineering bioplastic blends combining polysaccharide fractions isolated from corn by-products (cracked corn starch and corn fiber arabinoxylan) and engineering polymer resins (polyamides and polyesters) provided by NUREL, KTH optimized and implemented the chemical modification procedures. A total of 16 new formulations were produced and characterized using BARBARA polysaccharide substrates.

Large-scale production of the final target starch- and PA-based matrix for the build mold was carried out by AITIIP. To this end, a grafting approach was selected, developed, improved, and implemented. TECNOPACKAGING successfully produced the formulations selected at the laboratory level (work carried out by UNIPG) as the best candidates for the final 3D printing prototypes. Eight materials (33 spools) were produced. AITIIP developed a new 3D printer head, specifically designed to overcome the weaknesses of fused filament manufacturing: layer thickness quality and anisotropy. Modifications to the printer and the printhead device were required to optimize the printing process and sample properties.

Mechanical characterization of the injected and 3D-printed samples was also performed, with the primary objective of verifying the role of processing conditions in the overall performance of the formulation produced within the project. Disintegrability, recyclability, fragrance release, and antimicrobial activity were also evaluated. Three industrial prototypes were manufactured using FFF processing with BARBARA materials: a door fascia and interior trim for the automotive sector, and a mold for the construction sector. All prototypes were successfully validated by CRF and ACCIONA.

The key findings were disseminated through various tools and channels, including a website, social media, seven scientific publications, three brochures, nine videos, fifteen radio and television interviews, and seven newsletters (sent to stakeholders with target sectors and audiences).

A specific business plan was developed for the exploitable key results (those that represent a potential business) to drive the BARBARA project's value generation for the various partners and stakeholders in the value chain. The activities associated with the Business Plan are closely related to the BARBARA project's technological activities and directly feed into the dissemination and exploitation strategies, providing guidelines and key marketing aspects crucial to ensuring positive follow-up.