Proposal for an integrative and flexible categorisation framework for early-stage material exploration in design-oriented contexts

This paper proposes an integrative and flexible categorisation framework for early-stage material exploration in design-oriented contexts. The framework responds to the growing complexity of contemporary material landscapes, where conventional taxonomies and material databases often fail to adequately represent emerging, non-conventional, and sustainability-oriented materials. To develop the proposal, the authors conducted a critical review of 35 international material libraries, both physical and digital, and identified significant heterogeneity in categorisation criteria, as well as major gaps in the treatment of life-cycle-related information, aesthetic and sensorial characteristics, and less conventional material classes. The framework was then iteratively drafted, tested, refined, and consolidated through collaborative discussion among the authors and a pilot application involving 110 material case studies, with particular attention to recent and innovative materials. The resulting structure is designed to guide the organised and consistent comparison of material case studies in the early stages of the design process and, eventually, support the organisation of repositories of knowledge and material references. To do so, the framework integrates general information, material classification, technical data, aesthetic-sensorial characteristics, composition, life-cycle-related aspects, certifications, and links to the Sustainable Development Goals. Unlike late-stage selection tools focused mainly on engineering performance, the proposed framework is intended to support holistic exploration when uncertainty is high and information is often incomplete. Its modular and adaptable structure makes it suitable for use in design education, academic research, professional practice, and corporate R&D. By promoting clearer terminology, greater comparability, and more comprehensive material descriptions, the framework aims to become a practical tool for navigating the rapidly evolving field of materials and for supporting more organised case studies exploration and categorisation.