PhD Position in Interactions between wood surface chemistry and bio-based adhesives in advanced veneer-based products

Tallinn University of Technology School of Engineering: Department of Materials and Environmental Technology offers a 4-year PhD position in Chemical, Materials and Energy Technology.

The proposed PhD thesis topic: “Interactions between wood surface chemistry and bio-based adhesives in advanced veneer-based products”

Supervisors:

• Sup. Senior Lecturer Natalja Savest, Department of Materials and Environmental Technology: Laboratory of Biopolymer Technology
• Co-sup. Researcher Anti Rohumaa, Department of Materials and Environmental Technology: Laboratory of Wood Technology

Summary

The manufacture of veneer involves several sequential processes, starting with log storage and soaking at different temperatures, followed by peeling, drying under various conditions, and finally storing the prepared veneer in different environments. Additionally, veneers can undergo modifications to enhance their properties, such as fire-retardant treatments or durability improvements. It has been demonstrated that these manufacturing and modification steps can significantly alter the physical and chemical characteristics of veneer. Such changes are critical for the production of veneer-based products, particularly regarding adhesive bonding between veneer sheets, highlighting the importance of surface properties.

The aim of this PhD project is to investigate how veneer processing influences surface properties, with a particular focus on surface chemistry. Furthermore, the project will examine how these surface chemical characteristics affect interactions with bio-based adhesives and various veneer modification techniques. These relationships will be explored using both novel and established adhesive performance evaluation methods, including ABES.

Description

Wood offers significant environmental advantages over non-renewable construction materials, as forests sequester carbon and wood products store it long-term. The growing demand for sustainable and energy-efficient buildings has stimulated the development of new wood-based materials and construction practices. Although the wood construction sector is expanding rapidly, high-quality softwoods and hardwoods remain the primary raw materials. At the same time, lower-grade hardwoods, such as grey alder, black alder, and aspen are abundant but underutilized. Converting these species into high-value veneer-based products represents a significant opportunity for advancing the bioeconomy.

Engineered wood products rely heavily on adhesives, which are predominantly petrochemical-based. Regulatory pressure, sustainability targets, and circular-economy objectives are driving the need for high-performance bio-based adhesives. However, developing such adhesives is challenging due to costly, time-consuming testing and the complex interactions between adhesives and wood, including penetration, flow, curing behavior, and surface characteristics.

There is a clear need for systematic evaluation of how veneer processing parameters influence surface properties and bonding performance, particularly for underutilized hardwood species. While birch veneer has been extensively studied and will serve as a reference, optimal processing conditions for species such as black alder, grey alder, and aspen remain largely unknown. Understanding these relationships is essential for enabling the effective use of bio-based adhesives and supporting the development of innovative veneer-based products.

Wood surface quality is a major source of variability in bond performance. Common characterization methods, such as surface roughness, wettability, and chemical analysis provide useful but limited insight, as they often fail to capture deeper structural features that influence adhesion. Instruments such as the Automated Bonding Evaluation System (ABES) allow rapid assessment, but their sensitivity to wood surface inconsistencies is still poorly understood.

The goal of this PhD project is to investigate how veneer processing affects surface properties, with a particular focus on surface chemistry. Furthermore, the project will evaluate how these surface chemical characteristics influence interactions with bio-based adhesives and various veneer modification techniques. These relationships will be studied using both novel and established adhesive performance evaluation methods, including ABES.

• Critical analyzing veneer surface properties.
• Characterizing the surface properties in relationships to the manufacturing processes conditions.
• Investigating the veneer surface properties regarding the wood physical-chemical changes occurring on the surface during veneer preparation processing.
• Demonstrating the impact of veneer processing and surface properties on bond performance.
• Publishing the results in field specific peer-review journals and conferences.

• a master’s degree in wood chemistry or wood technology or wood-polymer science
• practical skills of laboratory of physical characterization of wood and veneer properties
• experience and skills in wood chemistry analysis and characterization
• a clear interest in the topic of the position
• excellent command of English
• strong and demonstrable writing and analytical skills
• capacity to work both as an independent researcher and as part of an international team

• experimental and/or theoretical knowledge of wood chemistry and analytical techniques for evaluating surface chemistry
• understanding of wood bonding mechanisms and adhesive chemistry

The information for the PhD admission is available at TalTech’s web-page:https://taltech.ee/en/phd-admission

The following application documents should be sent to [emailprotected]

• CV
• Motivation letter
• Degree certificates asrequired by the university
• A research plan for the topic, including the overall research strategy
• Copy of the passport or ID

We offer:

• 4-year PhD position in the perspective laboratory of Wood Technology with a broad network of international partners with a lot of co-operative projects.
• The chance to do high-level research in Wood technology field.
• Opportunities for conference visits, research stays and networking with globally leading universities and research centers in the field of wood technology.

About the hosting laboratory

TalTech offers excellent facilities and expertise to support this research. The university provides a wide range of analytical techniques for surface characterization and imaging, as well as a laboratory-scale veneer peeling and veneer-based product production line. This lab-scale production line enables precise control of processing parameters, allowing the creation of high-quality veneers suitable for engineered veneer products.

Additional information

For further information, please contact Dr. Natalja Savest ([emailprotected]).

Co-supervisor:Dr. Anti Rohumaa, Laboratory of Wood Technology: Department of Materials and Environmental Technology