Analysis of crystallinity variation by X-ray diffraction in wood extracted from different positions along tree height

• Grant number: 25/07021-0
• Support Opportunities: Scholarships abroad - Research Internship - Master's degree
• Start date: October 01, 2025
• End date: December 31, 2025
• Field of knowledge: Engineering - Civil Engineering - Structural Engineering
• Principal Investigator: Francisco Antonio Rocco Lahr
• Grantee: Maria Clara Cardoso
• Supervisor: Mauro Sardela
• Host Institution: Escola de Engenharia de São Carlos (EESC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Institution abroad: University of Illinois at Urbana-Champaign, United States
• Associated to the scholarship: 24/01522-5 - Variation of strength and stiffness properties obtained from material extracted from different positions along the tree height, BP.MS

Abstract

Wood is a lignocellulosic, bio-based material widely used in structural applications due to its light weight, specific strength, and renewability. Its mechanical properties are strongly influenced by the chemical composition and microscopic organization of the cell walls, particularly by the structure of cellulose, its main component. Native cellulose contains both crystalline and amorphous regions, and the proportion between these phases directly affects the material's stiffness and strength. In this context, the present study aims to assess the degree of crystallinity and crystallite size in four tropical species native to the Amazon Forest: Sclerolobium melinonii (Tachi preto), Vatairea paraensis (Fava amargosa), Trattinickia burseraefolia (Breu sucuruba), and Sclerolobium paraensis (Tachi branco). Samples were collected from three longitudinal positions along the trunk (base, middle, and top) to enable the investigation of potential variations in the studied properties across different stem regions. Crystallinity characterization will be conducted via X-ray diffraction (XRD) in both longitudinal and transverse directions to the wood fibers, using Cu-K¿ radiation. Crystallinity will be estimated through diffractogram analysis using Jade software and the Segal method, while crystallite size will be determined using the Scherrer equation. The results will contribute to the interpretation of data obtained in the ongoing master's research project, which aims to investigate potential variation in strength and stiffness properties along the height of the tree. The present crystallinity assessments will provide valuable scientific support for correlating the material's microscopic structure with its mechanical behavior. Additionally, the findings will assist in building a technical-scientific database on Brazilian tropical species from native Amazon Forest. (AU)